/* * Copyright (C) 2016 Red Hat, Inc. All rights reserved. * * _stats_get_extents_for_file() based in part on filefrag_fiemap() from * e2fsprogs/misc/filefrag.c. Copyright 2003 by Theodore Ts'o. * * This file is part of the device-mapper userspace tools. * * This copyrighted material is made available to anyone wishing to use, * modify, copy, or redistribute it subject to the terms and conditions * of the GNU Lesser General Public License v.2.1. * * You should have received a copy of the GNU Lesser General Public License * along with this program; if not, write to the Free Software Foundation, * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ #include "dmlib.h" #include "kdev_t.h" #include "math.h" /* log10() */ #include #include #include /* fstatfs */ #ifdef __linux__ #include /* FS_IOC_FIEMAP */ #endif #ifdef HAVE_LINUX_FIEMAP_H #include /* fiemap */ #endif #ifdef HAVE_LINUX_MAGIC_H #include /* BTRFS_SUPER_MAGIC */ #endif #define DM_STATS_REGION_NOT_PRESENT UINT64_MAX #define DM_STATS_GROUP_NOT_PRESENT DM_STATS_GROUP_NONE #define NSEC_PER_USEC 1000L #define NSEC_PER_MSEC 1000000L #define NSEC_PER_SEC 1000000000L #define PRECISE_ARG "precise_timestamps" #define HISTOGRAM_ARG "histogram:" #define STATS_ROW_BUF_LEN 4096 #define STATS_MSG_BUF_LEN 1024 #define STATS_FIE_BUF_LEN 2048 #define SECTOR_SHIFT 9L /* Histogram bin */ struct dm_histogram_bin { uint64_t upper; /* Upper bound on this bin. */ uint64_t count; /* Count value for this bin. */ }; struct dm_histogram { /* The stats handle this histogram belongs to. */ const struct dm_stats *dms; /* The region this histogram belongs to. */ const struct dm_stats_region *region; uint64_t sum; /* Sum of histogram bin counts. */ int nr_bins; /* Number of histogram bins assigned. */ struct dm_histogram_bin bins[0]; }; /* * See Documentation/device-mapper/statistics.txt for full descriptions * of the device-mapper statistics counter fields. */ struct dm_stats_counters { uint64_t reads; /* Num reads completed */ uint64_t reads_merged; /* Num reads merged */ uint64_t read_sectors; /* Num sectors read */ uint64_t read_nsecs; /* Num milliseconds spent reading */ uint64_t writes; /* Num writes completed */ uint64_t writes_merged; /* Num writes merged */ uint64_t write_sectors; /* Num sectors written */ uint64_t write_nsecs; /* Num milliseconds spent writing */ uint64_t io_in_progress; /* Num I/Os currently in progress */ uint64_t io_nsecs; /* Num milliseconds spent doing I/Os */ uint64_t weighted_io_nsecs; /* Weighted num milliseconds doing I/Os */ uint64_t total_read_nsecs; /* Total time spent reading in milliseconds */ uint64_t total_write_nsecs; /* Total time spent writing in milliseconds */ struct dm_histogram *histogram; /* Histogram. */ }; struct dm_stats_region { uint64_t region_id; /* as returned by @stats_list */ uint64_t group_id; uint64_t start; uint64_t len; uint64_t step; char *program_id; char *aux_data; uint64_t timescale; /* precise_timestamps is per-region */ struct dm_histogram *bounds; /* histogram configuration */ struct dm_histogram *histogram; /* aggregate cache */ struct dm_stats_counters *counters; }; struct dm_stats_group { uint64_t group_id; const char *alias; dm_bitset_t regions; struct dm_histogram *histogram; }; struct dm_stats { /* device binding */ int bind_major; /* device major that this dm_stats object is bound to */ int bind_minor; /* device minor that this dm_stats object is bound to */ char *bind_name; /* device-mapper device name */ char *bind_uuid; /* device-mapper UUID */ char *program_id; /* default program_id for this handle */ const char *name; /* cached device_name used for reporting */ struct dm_pool *mem; /* memory pool for region and counter tables */ struct dm_pool *hist_mem; /* separate pool for histogram tables */ struct dm_pool *group_mem; /* separate pool for group tables */ uint64_t nr_regions; /* total number of present regions */ uint64_t max_region; /* size of the regions table */ uint64_t interval_ns; /* sampling interval in nanoseconds */ uint64_t timescale; /* default sample value multiplier */ int precise; /* use precise_timestamps when creating regions */ struct dm_stats_region *regions; struct dm_stats_group *groups; /* statistics cursor */ uint64_t walk_flags; /* walk control flags */ uint64_t cur_flags; uint64_t cur_group; uint64_t cur_region; uint64_t cur_area; }; #define PROC_SELF_COMM "/proc/self/comm" static char *_program_id_from_proc(void) { FILE *comm = NULL; char buf[STATS_ROW_BUF_LEN]; if (!(comm = fopen(PROC_SELF_COMM, "r"))) return_NULL; if (!fgets(buf, sizeof(buf), comm)) { log_error("Could not read from %s", PROC_SELF_COMM); if (fclose(comm)) stack; return NULL; } if (fclose(comm)) stack; return dm_strdup(buf); } static uint64_t _nr_areas(uint64_t len, uint64_t step) { /* Default is one area. */ if (!len || !step) return 1; /* * drivers/md/dm-stats.c::message_stats_create() * A region may be sub-divided into areas with their own counters. * Any partial area at the end of the region is treated as an * additional complete area. */ return (len + step - 1) / step; } static uint64_t _nr_areas_region(struct dm_stats_region *region) { return _nr_areas(region->len, region->step); } struct dm_stats *dm_stats_create(const char *program_id) { size_t hist_hint = sizeof(struct dm_histogram_bin); size_t group_hint = sizeof(struct dm_stats_group); struct dm_stats *dms = NULL; if (!(dms = dm_zalloc(sizeof(*dms)))) return_NULL; /* FIXME: better hint. */ if (!(dms->mem = dm_pool_create("stats_pool", 4096))) { dm_free(dms); return_NULL; } if (!(dms->hist_mem = dm_pool_create("histogram_pool", hist_hint))) goto_bad; if (!(dms->group_mem = dm_pool_create("group_pool", group_hint))) goto_bad; if (!program_id || !strlen(program_id)) dms->program_id = _program_id_from_proc(); else dms->program_id = dm_strdup(program_id); if (!dms->program_id) { log_error("Could not allocate memory for program_id"); goto bad; } dms->bind_major = -1; dms->bind_minor = -1; dms->bind_name = NULL; dms->bind_uuid = NULL; dms->name = NULL; /* by default all regions use msec precision */ dms->timescale = NSEC_PER_MSEC; dms->precise = 0; dms->nr_regions = DM_STATS_REGION_NOT_PRESENT; dms->max_region = DM_STATS_REGION_NOT_PRESENT; dms->regions = NULL; /* maintain compatibility with earlier walk version */ dms->walk_flags = dms->cur_flags = DM_STATS_WALK_DEFAULT; return dms; bad: dm_pool_destroy(dms->mem); if (dms->hist_mem) dm_pool_destroy(dms->hist_mem); if (dms->group_mem) dm_pool_destroy(dms->group_mem); dm_free(dms); return NULL; } /* * Test whether the stats region pointed to by region is present. */ static int _stats_region_present(const struct dm_stats_region *region) { return !(region->region_id == DM_STATS_REGION_NOT_PRESENT); } /* * Test whether the stats group pointed to by group is present. */ static int _stats_group_present(const struct dm_stats_group *group) { return !(group->group_id == DM_STATS_GROUP_NOT_PRESENT); } /* * Test whether a stats group id is present. */ static int _stats_group_id_present(const struct dm_stats *dms, uint64_t id) { struct dm_stats_group *group = NULL; if (id == DM_STATS_GROUP_NOT_PRESENT) return 0; if (!dms) return_0; if (!dms->regions) return 0; if (id > dms->max_region) return 0; group = &dms->groups[id]; return _stats_group_present(group); } /* * Test whether the given region_id is a member of any group. */ static uint64_t _stats_region_is_grouped(const struct dm_stats* dms, uint64_t region_id) { uint64_t group_id; if (region_id == DM_STATS_GROUP_NOT_PRESENT) return 0; if (!_stats_region_present(&dms->regions[region_id])) return 0; group_id = dms->regions[region_id].group_id; return group_id != DM_STATS_GROUP_NOT_PRESENT; } static void _stats_histograms_destroy(struct dm_pool *mem, struct dm_stats_region *region) { /* Unpopulated handle. */ if (!region->counters) return; /* * Free everything in the pool back to the first histogram. */ if (region->counters[0].histogram) dm_pool_free(mem, region->counters[0].histogram); } static void _stats_region_destroy(struct dm_stats_region *region) { if (!_stats_region_present(region)) return; region->start = region->len = region->step = 0; region->timescale = 0; /* * Don't free counters and histogram bounds here: they are * dropped from the pool along with the corresponding * regions table. * * The following objects are all allocated with dm_malloc. */ region->counters = NULL; region->bounds = NULL; dm_free(region->program_id); region->program_id = NULL; dm_free(region->aux_data); region->aux_data = NULL; region->region_id = DM_STATS_REGION_NOT_PRESENT; } static void _stats_regions_destroy(struct dm_stats *dms) { struct dm_pool *mem = dms->mem; uint64_t i; if (!dms->regions) return; /* walk backwards to obey pool order */ for (i = dms->max_region; (i != DM_STATS_REGION_NOT_PRESENT); i--) { _stats_histograms_destroy(dms->hist_mem, &dms->regions[i]); _stats_region_destroy(&dms->regions[i]); } dm_pool_free(mem, dms->regions); dms->regions = NULL; } static void _stats_group_destroy(struct dm_stats_group *group) { if (!_stats_group_present(group)) return; group->histogram = NULL; if (group->alias) { dm_free((char *) group->alias); group->alias = NULL; } if (group->regions) { dm_bitset_destroy(group->regions); group->regions = NULL; } group->group_id = DM_STATS_GROUP_NOT_PRESENT; } static void _stats_groups_destroy(struct dm_stats *dms) { uint64_t i; if (!dms->groups) return; for (i = dms->max_region; (i != DM_STATS_REGION_NOT_PRESENT); i--) _stats_group_destroy(&dms->groups[i]); dm_pool_free(dms->group_mem, dms->groups); dms->groups = NULL; } static int _set_stats_device(struct dm_stats *dms, struct dm_task *dmt) { if (dms->bind_name) return dm_task_set_name(dmt, dms->bind_name); if (dms->bind_uuid) return dm_task_set_uuid(dmt, dms->bind_uuid); if (dms->bind_major > 0) return dm_task_set_major(dmt, dms->bind_major) && dm_task_set_minor(dmt, dms->bind_minor); return_0; } static int _stats_bound(const struct dm_stats *dms) { if (dms->bind_major > 0 || dms->bind_name || dms->bind_uuid) return 1; /* %p format specifier expects a void pointer. */ log_error("Stats handle at %p is not bound.", dms); return 0; } static void _stats_clear_binding(struct dm_stats *dms) { if (dms->bind_name) dm_pool_free(dms->mem, dms->bind_name); if (dms->bind_uuid) dm_pool_free(dms->mem, dms->bind_uuid); dm_free((char *) dms->name); dms->bind_name = dms->bind_uuid = NULL; dms->bind_major = dms->bind_minor = -1; dms->name = NULL; } int dm_stats_bind_devno(struct dm_stats *dms, int major, int minor) { _stats_clear_binding(dms); _stats_regions_destroy(dms); _stats_groups_destroy(dms); dms->bind_major = major; dms->bind_minor = minor; return 1; } int dm_stats_bind_name(struct dm_stats *dms, const char *name) { _stats_clear_binding(dms); _stats_regions_destroy(dms); _stats_groups_destroy(dms); if (!(dms->bind_name = dm_pool_strdup(dms->mem, name))) return_0; return 1; } int dm_stats_bind_uuid(struct dm_stats *dms, const char *uuid) { _stats_clear_binding(dms); _stats_regions_destroy(dms); _stats_groups_destroy(dms); if (!(dms->bind_uuid = dm_pool_strdup(dms->mem, uuid))) return_0; return 1; } int dm_stats_bind_from_fd(struct dm_stats *dms, int fd) { int major, minor; struct stat buf; if (fstat(fd, &buf)) { log_error("fstat failed for fd %d.", fd); return 0; } major = (int) MAJOR(buf.st_dev); minor = (int) MINOR(buf.st_dev); if (!dm_stats_bind_devno(dms, major, minor)) return_0; return 1; } static int _stats_check_precise_timestamps(const struct dm_stats *dms) { /* Already checked? */ if (dms && dms->precise) return 1; return dm_message_supports_precise_timestamps(); } int dm_stats_driver_supports_precise(void) { return _stats_check_precise_timestamps(NULL); } int dm_stats_driver_supports_histogram(void) { return _stats_check_precise_timestamps(NULL); } static int _fill_hist_arg(char *hist_arg, size_t hist_len, uint64_t scale, struct dm_histogram *bounds) { int i, l, len = 0, nr_bins; char *arg = hist_arg; uint64_t value; nr_bins = bounds->nr_bins; for (i = 0; i < nr_bins; i++) { value = bounds->bins[i].upper / scale; if ((l = dm_snprintf(arg, hist_len - len, FMTu64"%s", value, (i == (nr_bins - 1)) ? "" : ",")) < 0) return_0; len += l; arg += l; } return 1; } static void *_get_hist_arg(struct dm_histogram *bounds, uint64_t scale, size_t *len) { struct dm_histogram_bin *entry, *bins; size_t hist_len = 1; /* terminating '\0' */ double value; entry = bins = bounds->bins; entry += bounds->nr_bins - 1; while(entry >= bins) { value = (double) (entry--)->upper; /* Use lround to avoid size_t -> double cast warning. */ hist_len += 1 + (size_t) lround(log10(value / scale)); if (entry != bins) hist_len++; /* ',' */ } *len = hist_len; return dm_zalloc(hist_len); } static char *_build_histogram_arg(struct dm_histogram *bounds, int *precise) { struct dm_histogram_bin *entry, *bins; size_t hist_len; char *hist_arg; uint64_t scale; entry = bins = bounds->bins; /* Empty histogram is invalid. */ if (!bounds->nr_bins) { log_error("Cannot format empty histogram description."); return NULL; } /* Validate entries and set *precise if precision < 1ms. */ entry += bounds->nr_bins - 1; while (entry >= bins) { if (entry != bins) { if (entry->upper < (entry - 1)->upper) { log_error("Histogram boundaries must be in " "order of increasing magnitude."); return 0; } } /* * Only enable precise_timestamps automatically if any * value in the histogram bounds uses precision < 1ms. */ if (((entry--)->upper % NSEC_PER_MSEC) && !*precise) *precise = 1; } scale = (*precise) ? 1 : NSEC_PER_MSEC; /* Calculate hist_len and allocate a character buffer. */ if (!(hist_arg = _get_hist_arg(bounds, scale, &hist_len))) { log_error("Could not allocate memory for histogram argument."); return 0; } /* Fill hist_arg with boundary strings. */ if (!_fill_hist_arg(hist_arg, hist_len, scale, bounds)) goto_bad; return hist_arg; bad: log_error("Could not build histogram arguments."); dm_free(hist_arg); return NULL; } static struct dm_task *_stats_send_message(struct dm_stats *dms, char *msg) { struct dm_task *dmt; if (!(dmt = dm_task_create(DM_DEVICE_TARGET_MSG))) return_0; if (!_set_stats_device(dms, dmt)) goto_bad; if (!dm_task_set_message(dmt, msg)) goto_bad; if (!dm_task_run(dmt)) goto_bad; return dmt; bad: dm_task_destroy(dmt); return NULL; } /* * Cache the dm device_name for the device bound to dms. */ static int _stats_set_name_cache(struct dm_stats *dms) { struct dm_task *dmt; if (dms->name) return 1; if (!(dmt = dm_task_create(DM_DEVICE_INFO))) return_0; if (!_set_stats_device(dms, dmt)) goto_bad; if (!dm_task_run(dmt)) goto_bad; if (!(dms->name = dm_strdup(dm_task_get_name(dmt)))) goto_bad; dm_task_destroy(dmt); return 1; bad: log_error("Could not retrieve device-mapper name for device."); dm_task_destroy(dmt); return 0; } /* * update region group_id values */ static void _stats_update_groups(struct dm_stats *dms) { struct dm_stats_group *group; uint64_t group_id, i; for (group_id = 0; group_id < dms->max_region + 1; group_id++) { if (!_stats_group_id_present(dms, group_id)) continue; group = &dms->groups[group_id]; for (i = dm_bit_get_first(group->regions); i != DM_STATS_GROUP_NOT_PRESENT; i = dm_bit_get_next(group->regions, i)) dms->regions[i].group_id = group_id; } } static void _check_group_regions_present(struct dm_stats *dms, struct dm_stats_group *group) { dm_bitset_t regions = group->regions; int64_t i, group_id; group_id = i = dm_bit_get_first(regions); for (; i > 0; i = dm_bit_get_next(regions, i)) if (!_stats_region_present(&dms->regions[i])) { log_warn("Group descriptor " FMTd64 " contains " "non-existent region_id " FMTd64 ".", group_id, i); dm_bit_clear(regions, i); } } /* * Parse a DMS_GROUP group descriptor embedded in a region's aux_data. * * DMS_GROUP="ALIAS:MEMBERS" * * ALIAS: group alias * MEMBERS: list of group member region ids. * */ #define DMS_GROUP_TAG "DMS_GROUP=" #define DMS_GROUP_TAG_LEN (sizeof(DMS_GROUP_TAG) - 1) #define DMS_GROUP_SEP ':' #define DMS_AUX_SEP "#" static int _parse_aux_data_group(struct dm_stats *dms, struct dm_stats_region *region, struct dm_stats_group *group) { char *alias, *c, *end; dm_bitset_t regions; memset(group, 0, sizeof(*group)); group->group_id = DM_STATS_GROUP_NOT_PRESENT; /* find start of group tag */ c = strstr(region->aux_data, DMS_GROUP_TAG); if (!c) return 1; /* no group is not an error */ alias = c + strlen(DMS_GROUP_TAG); c = strchr(c, DMS_GROUP_SEP); if (!c) { log_error("Found malformed group tag while reading aux_data"); return 0; } /* terminate alias and advance to members */ *(c++) = '\0'; log_debug("Read alias '%s' from aux_data", alias); if (!c) { log_error("Found malformed group descriptor while " "reading aux_data, expected '%c'", DMS_GROUP_SEP); return 0; } /* if user aux_data follows make sure we have a terminated * string to pass to dm_bitset_parse_list(). */ end = strstr(c, DMS_AUX_SEP); if (!end) end = c + strlen(c); *(end++) = '\0'; if (!(regions = dm_bitset_parse_list(c, NULL, 0))) { log_error("Could not parse member list while " "reading group aux_data"); return 0; } group->group_id = dm_bit_get_first(regions); if (group->group_id != region->region_id) { log_error("Found invalid group descriptor in region " FMTu64 " aux_data.", region->region_id); group->group_id = DM_STATS_GROUP_NOT_PRESENT; goto bad; } group->regions = regions; group->alias = NULL; if (strlen(alias)) { group->alias = dm_strdup(alias); if (!group->alias) { log_error("Could not allocate memory for group alias"); goto bad; } } /* separate group tag from user aux_data */ if ((strlen(end) > 1) || strncmp(end, "-", 1)) c = dm_strdup(end); else c = dm_strdup(""); if (!c) { log_error("Could not allocate memory for user aux_data"); goto bad_alias; } dm_free(region->aux_data); region->aux_data = c; log_debug("Found group_id " FMTu64 ": alias=\"%s\"", group->group_id, (group->alias) ? group->alias : ""); return 1; bad_alias: dm_free((char *) group->alias); bad: dm_bitset_destroy(regions); return 0; } /* * Parse a histogram specification returned by the kernel in a * @stats_list response. */ static int _stats_parse_histogram_spec(struct dm_stats *dms, struct dm_stats_region *region, const char *histogram) { static const char _valid_chars[] = "0123456789,"; uint64_t scale = region->timescale, this_val = 0; struct dm_pool *mem = dms->hist_mem; struct dm_histogram_bin cur; struct dm_histogram hist; int nr_bins = 1; const char *c, *v, *val_start; char *p, *endptr = NULL; /* Advance past "histogram:". */ histogram = strchr(histogram, ':'); if (!histogram) { log_error("Could not parse histogram description."); return 0; } histogram++; /* @stats_list rows are newline terminated. */ if ((p = strchr(histogram, '\n'))) *p = '\0'; if (!dm_pool_begin_object(mem, sizeof(cur))) return_0; memset(&hist, 0, sizeof(hist)); hist.nr_bins = 0; /* fix later */ hist.region = region; hist.dms = dms; if (!dm_pool_grow_object(mem, &hist, sizeof(hist))) goto_bad; c = histogram; do { for (v = _valid_chars; *v; v++) if (*c == *v) break; if (!*v) { stack; goto badchar; } if (*c == ',') { log_error("Invalid histogram description: %s", histogram); goto bad; } else { val_start = c; endptr = NULL; errno = 0; this_val = strtoull(val_start, &endptr, 10); if (errno || !endptr) { log_error("Could not parse histogram boundary."); goto bad; } c = endptr; /* Advance to units, comma, or end. */ if (*c == ',') c++; else if (*c || (*c == ' ')) { /* Expected ',' or NULL. */ stack; goto badchar; } if (*c == ',') c++; cur.upper = scale * this_val; cur.count = 0; if (!dm_pool_grow_object(mem, &cur, sizeof(cur))) goto_bad; nr_bins++; } } while (*c && (*c != ' ')); /* final upper bound. */ cur.upper = UINT64_MAX; if (!dm_pool_grow_object(mem, &cur, sizeof(cur))) goto_bad; region->bounds = dm_pool_end_object(mem); if (!region->bounds) return_0; region->bounds->nr_bins = nr_bins; log_debug("Added region histogram spec with %d entries.", nr_bins); return 1; badchar: log_error("Invalid character in histogram: '%c' (0x%x)", *c, *c); bad: dm_pool_abandon_object(mem); return 0; } static int _stats_parse_list_region(struct dm_stats *dms, struct dm_stats_region *region, char *line) { char *p = NULL, string_data[STATS_ROW_BUF_LEN]; char *program_id, *aux_data, *stats_args; char *empty_string = (char *) ""; int r; memset(string_data, 0, sizeof(string_data)); /* * Parse fixed fields, line format: * * : + * * Maximum string data size is 4096 - 1 bytes. */ r = sscanf(line, FMTu64 ": " FMTu64 "+" FMTu64 " " FMTu64 " %4095c", ®ion->region_id, ®ion->start, ®ion->len, ®ion->step, string_data); if (r != 5) return_0; /* program_id is guaranteed to be first. */ program_id = string_data; /* * FIXME: support embedded '\ ' in string data: * s/strchr/_find_unescaped_space()/ */ if ((p = strchr(string_data, ' '))) { /* terminate program_id string. */ *p = '\0'; if (!strncmp(program_id, "-", 1)) program_id = empty_string; aux_data = p + 1; if ((p = strchr(aux_data, ' '))) { /* terminate aux_data string. */ *p = '\0'; stats_args = p + 1; } else stats_args = empty_string; /* no aux_data? */ if (!strncmp(aux_data, "-", 1)) aux_data = empty_string; else /* remove trailing newline */ aux_data[strlen(aux_data) - 1] = '\0'; } else aux_data = stats_args = empty_string; if (strstr(stats_args, PRECISE_ARG)) region->timescale = 1; else region->timescale = NSEC_PER_MSEC; if ((p = strstr(stats_args, HISTOGRAM_ARG))) { if (!_stats_parse_histogram_spec(dms, region, p)) return_0; } else region->bounds = NULL; /* clear aggregate cache */ region->histogram = NULL; region->group_id = DM_STATS_GROUP_NOT_PRESENT; if (!(region->program_id = dm_strdup(program_id))) return_0; if (!(region->aux_data = dm_strdup(aux_data))) { dm_free(region->program_id); return_0; } region->counters = NULL; return 1; } static int _stats_parse_list(struct dm_stats *dms, const char *resp) { uint64_t max_region = 0, nr_regions = 0; struct dm_stats_region cur, fill; struct dm_stats_group cur_group; struct dm_pool *mem = dms->mem, *group_mem = dms->group_mem; char line[STATS_ROW_BUF_LEN]; FILE *list_rows; if (!resp) { log_error("Could not parse NULL @stats_list response."); return 0; } _stats_regions_destroy(dms); _stats_groups_destroy(dms); /* no regions */ if (!strlen(resp)) { dms->nr_regions = dms->max_region = 0; dms->regions = NULL; return 1; } /* * dm_task_get_message_response() returns a 'const char *' but * since fmemopen also permits "w" it expects a 'char *'. */ if (!(list_rows = fmemopen((char *)resp, strlen(resp), "r"))) return_0; /* begin region table */ if (!dm_pool_begin_object(mem, 1024)) goto_bad; /* begin group table */ if (!dm_pool_begin_object(group_mem, 32)) goto_bad; while(fgets(line, sizeof(line), list_rows)) { cur_group.group_id = DM_STATS_GROUP_NOT_PRESENT; cur_group.regions = NULL; cur_group.alias = NULL; if (!_stats_parse_list_region(dms, &cur, line)) goto_bad; /* handle holes in the list of region_ids */ if (cur.region_id > max_region) { memset(&fill, 0, sizeof(fill)); memset(&cur_group, 0, sizeof(cur_group)); fill.region_id = DM_STATS_REGION_NOT_PRESENT; cur_group.group_id = DM_STATS_GROUP_NOT_PRESENT; do { if (!dm_pool_grow_object(mem, &fill, sizeof(fill))) goto_bad; if (!dm_pool_grow_object(group_mem, &cur_group, sizeof(cur_group))) goto_bad; } while (max_region++ < (cur.region_id - 1)); } if (cur.aux_data) if (!_parse_aux_data_group(dms, &cur, &cur_group)) log_error("Failed to parse group descriptor " "from region_id " FMTu64 " aux_data:" "'%s'", cur.region_id, cur.aux_data); /* continue */ if (!dm_pool_grow_object(mem, &cur, sizeof(cur))) goto_bad; if (!dm_pool_grow_object(group_mem, &cur_group, sizeof(cur_group))) goto_bad; max_region++; nr_regions++; } if (!nr_regions) /* no region data read from @stats_list */ goto bad; dms->nr_regions = nr_regions; dms->max_region = max_region - 1; dms->regions = dm_pool_end_object(mem); dms->groups = dm_pool_end_object(group_mem); dm_stats_foreach_group(dms) _check_group_regions_present(dms, &dms->groups[dms->cur_group]); _stats_update_groups(dms); if (fclose(list_rows)) stack; return 1; bad: if (fclose(list_rows)) stack; dm_pool_abandon_object(mem); dm_pool_abandon_object(group_mem); return 0; } int dm_stats_list(struct dm_stats *dms, const char *program_id) { char msg[STATS_MSG_BUF_LEN]; struct dm_task *dmt; int r; if (!_stats_bound(dms)) return_0; /* allow zero-length program_id for list */ if (!program_id) program_id = dms->program_id; if (!_stats_set_name_cache(dms)) return_0; if (dms->regions) _stats_regions_destroy(dms); r = dm_snprintf(msg, sizeof(msg), "@stats_list %s", program_id); if (r < 0) { log_error("Failed to prepare stats message."); return 0; } if (!(dmt = _stats_send_message(dms, msg))) return_0; if (!_stats_parse_list(dms, dm_task_get_message_response(dmt))) { log_error("Could not parse @stats_list response."); goto bad; } dm_task_destroy(dmt); return 1; bad: dm_task_destroy(dmt); return 0; } /* * Parse histogram data returned from a @stats_print operation. */ static int _stats_parse_histogram(struct dm_pool *mem, char *hist_str, struct dm_histogram **histogram, struct dm_stats_region *region) { static const char _valid_chars[] = "0123456789:"; struct dm_histogram *bounds = region->bounds; struct dm_histogram hist = { .nr_bins = region->bounds->nr_bins }; const char *c, *v, *val_start; struct dm_histogram_bin cur; uint64_t sum = 0, this_val; char *endptr = NULL; int bin = 0; c = hist_str; if (!dm_pool_begin_object(mem, sizeof(cur))) return_0; if (!dm_pool_grow_object(mem, &hist, sizeof(hist))) goto_bad; do { memset(&cur, 0, sizeof(cur)); for (v = _valid_chars; *v; v++) if (*c == *v) break; if (!*v) goto badchar; if (*c == ',') goto badchar; else { val_start = c; endptr = NULL; errno = 0; this_val = strtoull(val_start, &endptr, 10); if (errno || !endptr) { log_error("Could not parse histogram value."); goto bad; } c = endptr; /* Advance to colon, or end. */ if (*c == ':') c++; else if (*c & (*c != '\n')) /* Expected ':', '\n', or NULL. */ goto badchar; if (*c == ':') c++; cur.upper = bounds->bins[bin].upper; cur.count = this_val; sum += this_val; if (!dm_pool_grow_object(mem, &cur, sizeof(cur))) goto_bad; bin++; } } while (*c && (*c != '\n')); log_debug("Added region histogram data with %d entries.", hist.nr_bins); *histogram = dm_pool_end_object(mem); (*histogram)->sum = sum; return 1; badchar: log_error("Invalid character in histogram data: '%c' (0x%x)", *c, *c); bad: dm_pool_abandon_object(mem); return 0; } static int _stats_parse_region(struct dm_stats *dms, const char *resp, struct dm_stats_region *region, uint64_t timescale) { struct dm_histogram *hist = NULL; struct dm_pool *mem = dms->mem; struct dm_stats_counters cur; FILE *stats_rows = NULL; uint64_t start = 0, len = 0; char row[STATS_ROW_BUF_LEN]; int r; if (!resp) { log_error("Could not parse empty @stats_print response."); return 0; } region->start = UINT64_MAX; if (!dm_pool_begin_object(mem, 512)) goto_bad; /* * dm_task_get_message_response() returns a 'const char *' but * since fmemopen also permits "w" it expects a 'char *'. */ stats_rows = fmemopen((char *)resp, strlen(resp), "r"); if (!stats_rows) goto_bad; /* * Output format for each step-sized area of a region: * * + counters * * The first 11 counters have the same meaning as * /sys/block/ * /stat or /proc/diskstats. * * Please refer to Documentation/iostats.txt for details. * * 1. the number of reads completed * 2. the number of reads merged * 3. the number of sectors read * 4. the number of milliseconds spent reading * 5. the number of writes completed * 6. the number of writes merged * 7. the number of sectors written * 8. the number of milliseconds spent writing * 9. the number of I/Os currently in progress * 10. the number of milliseconds spent doing I/Os * 11. the weighted number of milliseconds spent doing I/Os * * Additional counters: * 12. the total time spent reading in milliseconds * 13. the total time spent writing in milliseconds * */ while (fgets(row, sizeof(row), stats_rows)) { r = sscanf(row, FMTu64 "+" FMTu64 /* start+len */ /* reads */ FMTu64 " " FMTu64 " " FMTu64 " " FMTu64 " " /* writes */ FMTu64 " " FMTu64 " " FMTu64 " " FMTu64 " " /* in flight & io nsecs */ FMTu64 " " FMTu64 " " FMTu64 " " /* tot read/write nsecs */ FMTu64 " " FMTu64, &start, &len, &cur.reads, &cur.reads_merged, &cur.read_sectors, &cur.read_nsecs, &cur.writes, &cur.writes_merged, &cur.write_sectors, &cur.write_nsecs, &cur.io_in_progress, &cur.io_nsecs, &cur.weighted_io_nsecs, &cur.total_read_nsecs, &cur.total_write_nsecs); if (r != 15) { log_error("Could not parse @stats_print row."); goto bad; } /* scale time values up if needed */ if (timescale != 1) { cur.read_nsecs *= timescale; cur.write_nsecs *= timescale; cur.io_nsecs *= timescale; cur.weighted_io_nsecs *= timescale; cur.total_read_nsecs *= timescale; cur.total_write_nsecs *= timescale; } if (region->bounds) { /* Find first histogram separator. */ char *hist_str = strchr(row, ':'); if (!hist_str) { log_error("Could not parse histogram value."); goto bad; } /* Find space preceding histogram. */ while (hist_str && *(hist_str - 1) != ' ') hist_str--; /* Use a separate pool for histogram objects since we * are growing the area table and each area's histogram * table simultaneously. */ if (!_stats_parse_histogram(dms->hist_mem, hist_str, &hist, region)) goto_bad; hist->dms = dms; hist->region = region; } cur.histogram = hist; if (!dm_pool_grow_object(mem, &cur, sizeof(cur))) goto_bad; if (region->start == UINT64_MAX) { region->start = start; region->step = len; /* area size is always uniform. */ } } if (region->start == UINT64_MAX) /* no area data read from @stats_print */ goto bad; region->len = (start + len) - region->start; region->timescale = timescale; region->counters = dm_pool_end_object(mem); if (fclose(stats_rows)) stack; return 1; bad: if (stats_rows) if (fclose(stats_rows)) stack; dm_pool_abandon_object(mem); return 0; } static void _stats_walk_next_present(const struct dm_stats *dms, uint64_t *flags, uint64_t *cur_r, uint64_t *cur_a, uint64_t *cur_g) { struct dm_stats_region *cur = NULL; /* start of walk: region loop advances *cur_r to 0. */ if (*cur_r != DM_STATS_REGION_NOT_PRESENT) cur = &dms->regions[*cur_r]; /* within current region? */ if (cur && (*flags & DM_STATS_WALK_AREA)) { if (++(*cur_a) < _nr_areas_region(cur)) return; else *cur_a = 0; } /* advance to next present, non-skipped region or end */ while (++(*cur_r) <= dms->max_region) { cur = &dms->regions[*cur_r]; if (!_stats_region_present(cur)) continue; if ((*flags & DM_STATS_WALK_SKIP_SINGLE_AREA)) if (!(*flags & DM_STATS_WALK_AREA)) if (_nr_areas_region(cur) < 2) continue; /* matching region found */ break; } return; } static void _stats_walk_next(const struct dm_stats *dms, uint64_t *flags, uint64_t *cur_r, uint64_t *cur_a, uint64_t *cur_g) { if (!dms || !dms->regions) return; if (*flags & DM_STATS_WALK_AREA) { /* advance to next area, region, or end */ _stats_walk_next_present(dms, flags, cur_r, cur_a, cur_g); return; } if (*flags & DM_STATS_WALK_REGION) { /* enable region aggregation */ *cur_a = DM_STATS_WALK_REGION; _stats_walk_next_present(dms, flags, cur_r, cur_a, cur_g); return; } if (*flags & DM_STATS_WALK_GROUP) { /* enable group aggregation */ *cur_r = *cur_a = DM_STATS_WALK_GROUP; while (!_stats_group_id_present(dms, ++(*cur_g)) && (*cur_g) < dms->max_region + 1) ; /* advance to next present group or end */ return; } log_error("stats_walk_next called with empty walk flags"); } static void _group_walk_start(const struct dm_stats *dms, uint64_t *flags, uint64_t *cur_r, uint64_t *cur_a, uint64_t *cur_g) { if (!(*flags & DM_STATS_WALK_GROUP)) return; *cur_a = *cur_r = DM_STATS_WALK_GROUP; *cur_g = 0; /* advance to next present group or end */ while ((*cur_g) <= dms->max_region) { if (_stats_region_is_grouped(dms, *cur_g)) break; (*cur_g)++; } if (*cur_g > dms->max_region) /* no groups to walk */ *flags &= ~DM_STATS_WALK_GROUP; } static void _stats_walk_start(const struct dm_stats *dms, uint64_t *flags, uint64_t *cur_r, uint64_t *cur_a, uint64_t *cur_g) { log_debug("starting stats walk with %s %s %s %s", (*flags & DM_STATS_WALK_AREA) ? "AREA" : "", (*flags & DM_STATS_WALK_REGION) ? "REGION" : "", (*flags & DM_STATS_WALK_GROUP) ? "GROUP" : "", (*flags & DM_STATS_WALK_SKIP_SINGLE_AREA) ? "SKIP" : ""); if (!dms->regions) return; if (!(*flags & (DM_STATS_WALK_AREA | DM_STATS_WALK_REGION))) return _group_walk_start(dms, flags, cur_r, cur_a, cur_g); /* initialise cursor state */ *cur_a = 0; *cur_r = DM_STATS_REGION_NOT_PRESENT; *cur_g = DM_STATS_GROUP_NOT_PRESENT; if (!(*flags & DM_STATS_WALK_AREA)) *cur_a = DM_STATS_WALK_REGION; /* advance to first present, non-skipped region */ _stats_walk_next_present(dms, flags, cur_r, cur_a, cur_g); } #define DM_STATS_WALK_MASK (DM_STATS_WALK_AREA \ | DM_STATS_WALK_REGION \ | DM_STATS_WALK_GROUP \ | DM_STATS_WALK_SKIP_SINGLE_AREA) int dm_stats_walk_init(struct dm_stats *dms, uint64_t flags) { if (!dms) return_0; if (flags & ~DM_STATS_WALK_MASK) { log_error("Unknown value in walk flags: 0x" FMTx64, (uint64_t) (flags & ~DM_STATS_WALK_MASK)); return 0; } dms->walk_flags = flags; log_debug("dm_stats_walk_init: initialised flags to " FMTx64, flags); return 1; } void dm_stats_walk_start(struct dm_stats *dms) { if (!dms || !dms->regions) return; dms->cur_flags = dms->walk_flags; _stats_walk_start(dms, &dms->cur_flags, &dms->cur_region, &dms->cur_area, &dms->cur_group); } void dm_stats_walk_next(struct dm_stats *dms) { _stats_walk_next(dms, &dms->cur_flags, &dms->cur_region, &dms->cur_area, &dms->cur_group); } void dm_stats_walk_next_region(struct dm_stats *dms) { dms->cur_flags &= ~DM_STATS_WALK_AREA; _stats_walk_next(dms, &dms->cur_flags, &dms->cur_region, &dms->cur_area, &dms->cur_group); } /* * Return 1 if any regions remain that are present and not skipped * by the current walk flags or 0 otherwise. */ static uint64_t _stats_walk_any_unskipped(const struct dm_stats *dms, uint64_t *flags, uint64_t *cur_r, uint64_t *cur_a) { struct dm_stats_region *region; uint64_t i; if (*cur_r > dms->max_region) return 0; for (i = *cur_r; i <= dms->max_region; i++) { region = &dms->regions[i]; if (!_stats_region_present(region)) continue; if ((*flags & DM_STATS_WALK_SKIP_SINGLE_AREA) && !(*flags & DM_STATS_WALK_AREA)) if (_nr_areas_region(region) < 2) continue; return 1; } return 0; } static void _stats_walk_end_areas(const struct dm_stats *dms, uint64_t *flags, uint64_t *cur_r, uint64_t *cur_a, uint64_t *cur_g) { int end = !_stats_walk_any_unskipped(dms, flags, cur_r, cur_a); if (!(*flags & DM_STATS_WALK_AREA)) return; if (!end) return; *flags &= ~DM_STATS_WALK_AREA; if (*flags & DM_STATS_WALK_REGION) { /* start region walk */ *cur_a = DM_STATS_WALK_REGION; *cur_r = DM_STATS_REGION_NOT_PRESENT; _stats_walk_next_present(dms, flags, cur_r, cur_a, cur_g); if (!_stats_walk_any_unskipped(dms, flags, cur_r, cur_a)) { /* no more regions */ *flags &= ~DM_STATS_WALK_REGION; if (!(*flags & DM_STATS_WALK_GROUP)) *cur_r = dms->max_region; } } if (*flags & DM_STATS_WALK_REGION) return; if (*flags & DM_STATS_WALK_GROUP) _group_walk_start(dms, flags, cur_r, cur_a, cur_g); } static int _stats_walk_end(const struct dm_stats *dms, uint64_t *flags, uint64_t *cur_r, uint64_t *cur_a, uint64_t *cur_g) { if (*flags & DM_STATS_WALK_AREA) { _stats_walk_end_areas(dms, flags, cur_r, cur_a, cur_g); goto out; } if (*flags & DM_STATS_WALK_REGION) { if (!_stats_walk_any_unskipped(dms, flags, cur_r, cur_a)) { *flags &= ~DM_STATS_WALK_REGION; _group_walk_start(dms, flags, cur_r, cur_a, cur_g); } goto out; } if (*flags & DM_STATS_WALK_GROUP) { if (*cur_g <= dms->max_region) goto out; *flags &= ~DM_STATS_WALK_GROUP; } out: return !(*flags & ~DM_STATS_WALK_SKIP_SINGLE_AREA); } int dm_stats_walk_end(struct dm_stats *dms) { if (!dms) return 1; if (_stats_walk_end(dms, &dms->cur_flags, &dms->cur_region, &dms->cur_area, &dms->cur_group)) { dms->cur_flags = dms->walk_flags; return 1; } return 0; } dm_stats_obj_type_t dm_stats_object_type(const struct dm_stats *dms, uint64_t region_id, uint64_t area_id) { uint64_t group_id; region_id = (region_id == DM_STATS_REGION_CURRENT) ? dms->cur_region : region_id ; area_id = (area_id == DM_STATS_AREA_CURRENT) ? dms->cur_area : area_id ; if (region_id == DM_STATS_REGION_NOT_PRESENT) /* no region */ return DM_STATS_OBJECT_TYPE_NONE; if (region_id & DM_STATS_WALK_GROUP) { if (region_id == DM_STATS_WALK_GROUP) /* indirect group_id from cursor */ group_id = dms->cur_group; else /* immediate group_id encoded in region_id */ group_id = region_id & ~DM_STATS_WALK_GROUP; if (!_stats_group_id_present(dms, group_id)) return DM_STATS_OBJECT_TYPE_NONE; return DM_STATS_OBJECT_TYPE_GROUP; } if (region_id > dms->max_region) /* end of table */ return DM_STATS_OBJECT_TYPE_NONE; if (area_id & DM_STATS_WALK_REGION) /* aggregate region */ return DM_STATS_OBJECT_TYPE_REGION; /* plain region_id and area_id */ return DM_STATS_OBJECT_TYPE_AREA; } dm_stats_obj_type_t dm_stats_current_object_type(const struct dm_stats *dms) { /* dm_stats_object_type will decode region/area */ return dm_stats_object_type(dms, DM_STATS_REGION_CURRENT, DM_STATS_AREA_CURRENT); } uint64_t dm_stats_get_region_nr_areas(const struct dm_stats *dms, uint64_t region_id) { struct dm_stats_region *region = NULL; /* groups or aggregate regions cannot be subdivided */ if (region_id & DM_STATS_WALK_GROUP) return 1; region = &dms->regions[region_id]; return _nr_areas_region(region); } uint64_t dm_stats_get_current_nr_areas(const struct dm_stats *dms) { /* groups or aggregate regions cannot be subdivided */ if (dms->cur_region & DM_STATS_WALK_GROUP) return 1; return dm_stats_get_region_nr_areas(dms, dms->cur_region); } uint64_t dm_stats_get_nr_areas(const struct dm_stats *dms) { uint64_t nr_areas = 0, flags = DM_STATS_WALK_AREA; /* use a separate cursor */ uint64_t cur_region = 0, cur_area = 0, cur_group = 0; /* no regions to visit? */ if (!dms->regions) return 0; flags = DM_STATS_WALK_AREA; _stats_walk_start(dms, &flags, &cur_region, &cur_area, &cur_group); do { nr_areas += dm_stats_get_current_nr_areas(dms); _stats_walk_next(dms, &flags, &cur_region, &cur_area, &cur_group); } while (!_stats_walk_end(dms, &flags, &cur_region, &cur_area, &cur_group)); return nr_areas; } int dm_stats_group_present(const struct dm_stats *dms, uint64_t group_id) { return _stats_group_id_present(dms, group_id); } int dm_stats_get_region_nr_histogram_bins(const struct dm_stats *dms, uint64_t region_id) { region_id = (region_id == DM_STATS_REGION_CURRENT) ? dms->cur_region : region_id ; /* FIXME: support group histograms if all region bounds match */ if (region_id & DM_STATS_WALK_GROUP) return 0; if (!dms->regions[region_id].bounds) return 0; return dms->regions[region_id].bounds->nr_bins; } /* * Fill buf with a list of set regions in the regions bitmap. Consecutive * ranges of set region IDs are output using "M-N" range notation. * * The number of bytes consumed is returned or zero on error. */ static size_t _stats_group_tag_fill(const struct dm_stats *dms, dm_bitset_t regions, char *buf, size_t buflen) { int i, j, r, next, last = 0; size_t used = 0; last = dm_bit_get_last(regions); i = dm_bit_get_first(regions); for(; i >= 0; i = dm_bit_get_next(regions, i)) { /* find range end */ j = i; do next = j + 1; while ((j = dm_bit_get_next(regions, j)) == next); /* set to last set bit */ j = next - 1; /* handle range vs. single region */ if (i != j) r = dm_snprintf(buf, buflen, FMTu64 "-" FMTu64 "%s", (uint64_t) i, (uint64_t) j, (j == last) ? "" : ","); else r = dm_snprintf(buf, buflen, FMTu64 "%s", (uint64_t) i, (i == last) ? "" : ","); if (r < 0) goto_bad; i = next; /* skip handled bits if in range */ buf += r; used += r; } return used; bad: log_error("Could not format group list."); return 0; } /* * Calculate the space required to hold a string description of the group * described by the regions bitset using comma separated list in range * notation ("A,B,C,M-N"). */ static size_t _stats_group_tag_len(const struct dm_stats *dms, dm_bitset_t regions) { int64_t i, j, next, nr_regions = 0; size_t buflen = 0, id_len = 0; /* check region ids and find last set bit */ i = dm_bit_get_first(regions); for (; i >= 0; i = dm_bit_get_next(regions, i)) { /* length of region_id or range start in characters */ id_len = (i) ? 1 + (size_t) log10(i) : 1; buflen += id_len; j = i; do next = j + 1; while ((j = dm_bit_get_next(regions, j)) == next); /* set to last set bit */ j = next - 1; nr_regions += j - i + 1; /* handle range */ if (i != j) { /* j is always > i, which is always >= 0 */ id_len = 1 + (size_t) log10(j); buflen += id_len + 1; /* range end plus "-" */ } buflen++; i = next; /* skip bits if handling range */ } return buflen; } /* * Build a DMS_GROUP="..." tag for the group specified by group_id, * to be stored in the corresponding region's aux_data field. */ static char *_build_group_tag(struct dm_stats *dms, uint64_t group_id) { char *aux_string, *buf; dm_bitset_t regions; const char *alias; size_t buflen = 0; int r; regions = dms->groups[group_id].regions; alias = dms->groups[group_id].alias; buflen = _stats_group_tag_len(dms, regions); if (!buflen) return_0; buflen += DMS_GROUP_TAG_LEN; buflen += 1 + (alias ? strlen(alias) : 0); /* 'alias:' */ buf = aux_string = dm_malloc(buflen); if (!buf) { log_error("Could not allocate memory for aux_data string."); return NULL; } if (!dm_strncpy(buf, DMS_GROUP_TAG, DMS_GROUP_TAG_LEN + 1)) goto_bad; buf += DMS_GROUP_TAG_LEN; buflen -= DMS_GROUP_TAG_LEN; r = dm_snprintf(buf, buflen, "%s%c", alias ? alias : "", DMS_GROUP_SEP); if (r < 0) goto_bad; buf += r; buflen -= r; r = _stats_group_tag_fill(dms, regions, buf, buflen); if (!r) goto_bad; return aux_string; bad: log_error("Could not format group aux_data."); dm_free(aux_string); return NULL; } /* * Store updated aux_data for a region. The aux_data is passed to the * kernel using the @stats_set_aux message. Any required group tag is * generated from the current group table and included in the message. */ static int _stats_set_aux(struct dm_stats *dms, uint64_t region_id, const char *aux_data) { const char *group_tag = NULL; struct dm_task *dmt = NULL; char msg[STATS_MSG_BUF_LEN]; /* group data required? */ if (_stats_group_id_present(dms, region_id)) { group_tag = _build_group_tag(dms, region_id); if (!group_tag) { log_error("Could not build group descriptor for " "region ID " FMTu64, region_id); goto bad; } } if (dm_snprintf(msg, sizeof(msg), "@stats_set_aux " FMTu64 " %s%s%s ", region_id, (group_tag) ? group_tag : "", (group_tag) ? DMS_AUX_SEP : "", (strlen(aux_data)) ? aux_data : "-") < 0) { log_error("Could not prepare @stats_set_aux message"); goto bad; } if (!(dmt = _stats_send_message(dms, msg))) goto_bad; dm_free((char *) group_tag); /* no response to a @stats_set_aux message */ dm_task_destroy(dmt); return 1; bad: dm_free((char *) group_tag); return 0; } /* * Maximum length of a "start+end" range string: * Two 20 digit uint64_t, '+', and NULL. */ #define RANGE_LEN 42 static int _stats_create_region(struct dm_stats *dms, uint64_t *region_id, uint64_t start, uint64_t len, int64_t step, int precise, const char *hist_arg, const char *program_id, const char *aux_data) { char msg[STATS_MSG_BUF_LEN], range[RANGE_LEN], *endptr = NULL; const char *err_fmt = "Could not prepare @stats_create %s."; const char *precise_str = PRECISE_ARG; const char *resp, *opt_args = NULL; struct dm_task *dmt = NULL; int r = 0, nr_opt = 0; if (!_stats_bound(dms)) return_0; if (!program_id || !strlen(program_id)) program_id = dms->program_id; if (start || len) { if (dm_snprintf(range, sizeof(range), FMTu64 "+" FMTu64, start, len) < 0) { log_error(err_fmt, "range"); return 0; } } if (precise < 0) precise = dms->precise; if (precise) nr_opt++; else precise_str = ""; if (hist_arg) nr_opt++; else hist_arg = ""; if (nr_opt) { if ((dm_asprintf((char **)&opt_args, "%d %s %s%s", nr_opt, precise_str, (strlen(hist_arg)) ? HISTOGRAM_ARG : "", hist_arg)) < 0) { log_error(err_fmt, PRECISE_ARG " option."); return 0; } } else opt_args = dm_strdup(""); if (dm_snprintf(msg, sizeof(msg), "@stats_create %s %s" FMTu64 " %s %s %s", (start || len) ? range : "-", (step < 0) ? "/" : "", (uint64_t)llabs(step), opt_args, program_id, aux_data) < 0) { log_error(err_fmt, "message"); dm_free((void *) opt_args); return 0; } if (!(dmt = _stats_send_message(dms, msg))) goto_out; resp = dm_task_get_message_response(dmt); if (!resp) { log_error("Could not parse empty @stats_create response."); goto out; } if (region_id) { errno = 0; *region_id = strtoull(resp, &endptr, 10); if (errno || resp == endptr) goto_out; } r = 1; out: if (dmt) dm_task_destroy(dmt); dm_free((void *) opt_args); return r; } int dm_stats_create_region(struct dm_stats *dms, uint64_t *region_id, uint64_t start, uint64_t len, int64_t step, int precise, struct dm_histogram *bounds, const char *program_id, const char *user_data) { char *hist_arg = NULL; int r = 0; /* Nanosecond counters and histograms both need precise_timestamps. */ if ((precise || bounds) && !_stats_check_precise_timestamps(dms)) return_0; if (bounds) { /* _build_histogram_arg enables precise if vals < 1ms. */ if (!(hist_arg = _build_histogram_arg(bounds, &precise))) goto_out; } r = _stats_create_region(dms, region_id, start, len, step, precise, hist_arg, program_id, user_data); dm_free(hist_arg); out: return r; } static void _stats_clear_group_regions(struct dm_stats *dms, uint64_t group_id) { struct dm_stats_group *group; uint64_t i; group = &dms->groups[group_id]; for (i = dm_bit_get_first(group->regions); i != DM_STATS_GROUP_NOT_PRESENT; i = dm_bit_get_next(group->regions, i)) dms->regions[i].group_id = DM_STATS_GROUP_NOT_PRESENT; } static int _stats_remove_region_id_from_group(struct dm_stats *dms, uint64_t region_id) { struct dm_stats_region *region = &dms->regions[region_id]; uint64_t group_id = region->group_id; dm_bitset_t regions = dms->groups[group_id].regions; if (!_stats_region_is_grouped(dms, region_id)) return_0; dm_bit_clear(regions, region_id); /* removing group leader? */ if (region_id == group_id) { _stats_clear_group_regions(dms, group_id); _stats_group_destroy(&dms->groups[group_id]); } return _stats_set_aux(dms, group_id, dms->regions[group_id].aux_data); } static int _stats_delete_region(struct dm_stats *dms, uint64_t region_id) { char msg[STATS_MSG_BUF_LEN]; struct dm_task *dmt; if (_stats_region_is_grouped(dms, region_id)) if (!_stats_remove_region_id_from_group(dms, region_id)) { log_error("Could not remove region ID " FMTu64 " from " "group ID " FMTu64, region_id, dms->regions[region_id].group_id); return 0; } if (dm_snprintf(msg, sizeof(msg), "@stats_delete " FMTu64, region_id) < 0) { log_error("Could not prepare @stats_delete message."); return 0; } dmt = _stats_send_message(dms, msg); if (!dmt) return_0; dm_task_destroy(dmt); return 1; } int dm_stats_delete_region(struct dm_stats *dms, uint64_t region_id) { int listed = 0; if (!_stats_bound(dms)) return_0; /* * To correctly delete a region, that may be part of a group, a * listed handle is required, since the region may need to be * removed from another region's group descriptor; earlier * versions of the region deletion interface do not have this * requirement since there are no dependencies between regions. * * Listing a previously unlisted handle has numerous * side-effects on other calls and operations (e.g. stats * walks), especially when returning to a function that depends * on the state of the region table, or statistics cursor. * * To avoid changing the semantics of the API, and the need for * a versioned symbol, maintain a flag indicating when a listing * has been carried out, and drop the region table before * returning. * * This ensures compatibility with programs compiled against * earlier versions of libdm. */ if (!dms->regions && !(listed = dm_stats_list(dms, dms->program_id))) { log_error("Could not obtain region list while deleting " "region ID " FMTu64, region_id); goto bad; } if (!dm_stats_get_nr_regions(dms)) { log_error("Could not delete region ID " FMTu64 ": " "no regions found", region_id); goto bad; } /* includes invalid and special region_id values */ if (!dm_stats_region_present(dms, region_id)) { log_error("Region ID " FMTu64 " does not exist", region_id); goto bad; } if (!_stats_delete_region(dms, region_id)) goto bad; if (!listed) /* wipe region and mark as not present */ _stats_region_destroy(&dms->regions[region_id]); else /* return handle to prior state */ _stats_regions_destroy(dms); return 1; bad: if (listed) _stats_regions_destroy(dms); return 0; } int dm_stats_clear_region(struct dm_stats *dms, uint64_t region_id) { char msg[STATS_MSG_BUF_LEN]; struct dm_task *dmt; if (!_stats_bound(dms)) return_0; if (dm_snprintf(msg, sizeof(msg), "@stats_clear " FMTu64, region_id) < 0) { log_error("Could not prepare @stats_clear message."); return 0; } dmt = _stats_send_message(dms, msg); if (!dmt) return_0; dm_task_destroy(dmt); return 1; } static struct dm_task *_stats_print_region(struct dm_stats *dms, uint64_t region_id, unsigned start_line, unsigned num_lines, unsigned clear) { /* @stats_print[_clear] [ ] */ const char *err_fmt = "Could not prepare @stats_print %s."; char msg[STATS_MSG_BUF_LEN], lines[RANGE_LEN]; struct dm_task *dmt = NULL; if (start_line || num_lines) if (dm_snprintf(lines, sizeof(lines), "%u %u", start_line, num_lines) < 0) { log_error(err_fmt, "row specification"); return NULL; } if (dm_snprintf(msg, sizeof(msg), "@stats_print%s " FMTu64 " %s", (clear) ? "_clear" : "", region_id, (start_line || num_lines) ? lines : "") < 0) { log_error(err_fmt, "message"); return NULL; } if (!(dmt = _stats_send_message(dms, msg))) return_NULL; return dmt; } char *dm_stats_print_region(struct dm_stats *dms, uint64_t region_id, unsigned start_line, unsigned num_lines, unsigned clear) { char *resp = NULL; struct dm_task *dmt = NULL; const char *response; if (!_stats_bound(dms)) return_0; /* * FIXME: 'print' can be emulated for groups or aggregate regions * by populating the handle and emitting aggregate counter data * in the kernel print format. */ if (region_id == DM_STATS_WALK_GROUP) return_0; dmt = _stats_print_region(dms, region_id, start_line, num_lines, clear); if (!dmt) return_0; if (!(response = dm_task_get_message_response(dmt))) goto_out; if (!(resp = dm_pool_strdup(dms->mem, response))) log_error("Could not allocate memory for response buffer."); out: dm_task_destroy(dmt); return resp; } void dm_stats_buffer_destroy(struct dm_stats *dms, char *buffer) { dm_pool_free(dms->mem, buffer); } uint64_t dm_stats_get_nr_regions(const struct dm_stats *dms) { if (!dms) return_0; if (!dms->regions) return 0; return dms->nr_regions; } uint64_t dm_stats_get_nr_groups(const struct dm_stats *dms) { uint64_t group_id, nr_groups = 0; if (!dms) return_0; /* no regions or groups? */ if (!dms->regions || !dms->groups) return 0; for (group_id = 0; group_id <= dms->max_region; group_id++) if (dms->groups[group_id].group_id != DM_STATS_GROUP_NOT_PRESENT) nr_groups++; return nr_groups; } /** * Test whether region_id is present in this set of stats data. */ int dm_stats_region_present(const struct dm_stats *dms, uint64_t region_id) { if (!dms->regions) return_0; if (region_id > dms->max_region) return 0; return _stats_region_present(&dms->regions[region_id]); } static int _dm_stats_populate_region(struct dm_stats *dms, uint64_t region_id, const char *resp) { struct dm_stats_region *region = &dms->regions[region_id]; if (!_stats_bound(dms)) return_0; if (!region) { log_error("Cannot populate empty handle before dm_stats_list()."); return 0; } if (!_stats_parse_region(dms, resp, region, region->timescale)) { log_error("Could not parse @stats_print message response."); return 0; } region->region_id = region_id; return 1; } int dm_stats_populate(struct dm_stats *dms, const char *program_id, uint64_t region_id) { int all_regions = (region_id == DM_STATS_REGIONS_ALL); struct dm_task *dmt = NULL; /* @stats_print task */ uint64_t saved_flags; /* saved walk flags */ const char *resp; /* * We are about do destroy and re-create the region table, so it * is safe to use the cursor embedded in the stats handle: just * save a copy of the current walk_flags to restore later. */ saved_flags = dms->walk_flags; if (!_stats_bound(dms)) return_0; if ((!all_regions) && (region_id & DM_STATS_WALK_GROUP)) { log_error("Invalid region_id for dm_stats_populate: " "DM_STATS_WALK_GROUP"); return 0; } if (!dms->nr_regions) { log_error("No regions registered."); return 0; } /* allow zero-length program_id for populate */ if (!program_id) program_id = dms->program_id; if (all_regions && !dm_stats_list(dms, program_id)) { log_error("Could not parse @stats_list response."); goto bad; } else if (!_stats_set_name_cache(dms)) { goto_bad; } dms->walk_flags = DM_STATS_WALK_REGION; dm_stats_walk_start(dms); do { region_id = (all_regions) ? dm_stats_get_current_region(dms) : region_id; /* obtain all lines and clear counter values */ if (!(dmt = _stats_print_region(dms, region_id, 0, 0, 1))) goto_bad; resp = dm_task_get_message_response(dmt); if (!_dm_stats_populate_region(dms, region_id, resp)) { dm_task_destroy(dmt); goto_bad; } dm_task_destroy(dmt); dm_stats_walk_next(dms); } while (all_regions && !dm_stats_walk_end(dms)); dms->walk_flags = saved_flags; return 1; bad: dms->walk_flags = saved_flags; _stats_regions_destroy(dms); dms->regions = NULL; return 0; } /** * destroy a dm_stats object and all associated regions and counter sets. */ void dm_stats_destroy(struct dm_stats *dms) { if (!dms) return; _stats_regions_destroy(dms); _stats_groups_destroy(dms); _stats_clear_binding(dms); dm_pool_destroy(dms->mem); dm_pool_destroy(dms->hist_mem); dm_pool_destroy(dms->group_mem); dm_free(dms->program_id); dm_free((char *) dms->name); dm_free(dms); } /* * Walk each area that is a member of region_id rid. * i is a variable of type int that holds the current area_id. */ #define _foreach_region_area(dms, rid, i) \ for ((i) = 0; (i) < _nr_areas_region(&dms->regions[(rid)]); (i)++) \ /* * Walk each region that is a member of group_id gid. * i is a variable of type int that holds the current region_id. */ #define _foreach_group_region(dms, gid, i) \ for ((i) = dm_bit_get_first((dms)->groups[(gid)].regions); \ (i) != DM_STATS_GROUP_NOT_PRESENT; \ (i) = dm_bit_get_next((dms)->groups[(gid)].regions, (i))) \ /* * Walk each region that is a member of group_id gid visiting each * area within the region. * i is a variable of type int that holds the current region_id. * j is a variable of type int variable that holds the current area_id. */ #define _foreach_group_area(dms, gid, i, j) \ _foreach_group_region(dms, gid, i) \ _foreach_region_area(dms, i, j) static uint64_t _stats_get_counter(const struct dm_stats *dms, const struct dm_stats_counters *area, dm_stats_counter_t counter) { switch(counter) { case DM_STATS_READS_COUNT: return area->reads; case DM_STATS_READS_MERGED_COUNT: return area->reads_merged; case DM_STATS_READ_SECTORS_COUNT: return area->read_sectors; case DM_STATS_READ_NSECS: return area->read_nsecs; case DM_STATS_WRITES_COUNT: return area->writes; case DM_STATS_WRITES_MERGED_COUNT: return area->writes_merged; case DM_STATS_WRITE_SECTORS_COUNT: return area->write_sectors; case DM_STATS_WRITE_NSECS: return area->write_nsecs; case DM_STATS_IO_IN_PROGRESS_COUNT: return area->io_in_progress; case DM_STATS_IO_NSECS: return area->io_nsecs; case DM_STATS_WEIGHTED_IO_NSECS: return area->weighted_io_nsecs; case DM_STATS_TOTAL_READ_NSECS: return area->total_read_nsecs; case DM_STATS_TOTAL_WRITE_NSECS: return area->total_write_nsecs; case DM_STATS_NR_COUNTERS: default: log_error("Attempt to read invalid counter: %d", counter); } return 0; } uint64_t dm_stats_get_counter(const struct dm_stats *dms, dm_stats_counter_t counter, uint64_t region_id, uint64_t area_id) { uint64_t i, j, sum = 0; /* aggregation */ int sum_regions = 0; struct dm_stats_region *region; struct dm_stats_counters *area; region_id = (region_id == DM_STATS_REGION_CURRENT) ? dms->cur_region : region_id ; area_id = (area_id == DM_STATS_REGION_CURRENT) ? dms->cur_area : area_id ; sum_regions = !!(region_id & DM_STATS_WALK_GROUP); if (region_id == DM_STATS_WALK_GROUP) /* group walk using the cursor */ region_id = dms->cur_group; else if (region_id & DM_STATS_WALK_GROUP) /* group walk using immediate group_id */ region_id &= ~DM_STATS_WALK_GROUP; region = &dms->regions[region_id]; /* * All statistics aggregation takes place here: aggregate metrics * are calculated as normal using the aggregated counter values * returned for the region or group specified. */ if (_stats_region_is_grouped(dms, region_id) && (sum_regions)) { /* group */ if (area_id & DM_STATS_WALK_GROUP) _foreach_group_area(dms, region->group_id, i, j) { area = &dms->regions[i].counters[j]; sum += _stats_get_counter(dms, area, counter); } else _foreach_group_region(dms, region->group_id, i) { area = &dms->regions[i].counters[area_id]; sum += _stats_get_counter(dms, area, counter); } } else if (area_id == DM_STATS_WALK_REGION) { /* aggregate region */ _foreach_region_area(dms, region_id, j) { area = &dms->regions[region_id].counters[j]; sum += _stats_get_counter(dms, area, counter); } } else { /* plain region / area */ area = ®ion->counters[area_id]; sum = _stats_get_counter(dms, area, counter); } return sum; } /* * Methods for accessing named counter fields. All methods share the * following naming scheme and prototype: * * uint64_t dm_stats_get_COUNTER(const struct dm_stats *, uint64_t, uint64_t) * * Where the two integer arguments are the region_id and area_id * respectively. * * name is the name of the counter (lower case) * counter is the part of the enum name following DM_STATS_ (upper case) */ #define MK_STATS_GET_COUNTER_FN(name, counter) \ uint64_t dm_stats_get_ ## name(const struct dm_stats *dms, \ uint64_t region_id, uint64_t area_id) \ { \ return dm_stats_get_counter(dms, DM_STATS_ ## counter, \ region_id, area_id); \ } MK_STATS_GET_COUNTER_FN(reads, READS_COUNT) MK_STATS_GET_COUNTER_FN(reads_merged, READS_MERGED_COUNT) MK_STATS_GET_COUNTER_FN(read_sectors, READ_SECTORS_COUNT) MK_STATS_GET_COUNTER_FN(read_nsecs, READ_NSECS) MK_STATS_GET_COUNTER_FN(writes, WRITES_COUNT) MK_STATS_GET_COUNTER_FN(writes_merged, WRITES_MERGED_COUNT) MK_STATS_GET_COUNTER_FN(write_sectors, WRITE_SECTORS_COUNT) MK_STATS_GET_COUNTER_FN(write_nsecs, WRITE_NSECS) MK_STATS_GET_COUNTER_FN(io_in_progress, IO_IN_PROGRESS_COUNT) MK_STATS_GET_COUNTER_FN(io_nsecs, IO_NSECS) MK_STATS_GET_COUNTER_FN(weighted_io_nsecs, WEIGHTED_IO_NSECS) MK_STATS_GET_COUNTER_FN(total_read_nsecs, TOTAL_READ_NSECS) MK_STATS_GET_COUNTER_FN(total_write_nsecs, TOTAL_WRITE_NSECS) #undef MK_STATS_GET_COUNTER_FN /* * Floating point stats metric functions * * Called from dm_stats_get_metric() to calculate the value of * the requested metric. * * int _metric_name(const struct dm_stats *dms, * struct dm_stats_counters *c, * double *value); * * Calculate a metric value from the counter data for the given * identifiers and store it in the memory pointed to by value, * applying group or region aggregation if enabled. * * Return one on success or zero on failure. * * To add a new metric: * * o Add a new name to the dm_stats_metric_t enum. * o Create a _metric_fn() to calculate the new metric. * o Add _metric_fn to the _metrics function table * (entries in enum order). * o Do not add a new named public function for the metric - * users of new metrics are encouraged to convert to the enum * based metric interface. * */ static int _rd_merges_per_sec(const struct dm_stats *dms, double *rrqm, uint64_t region_id, uint64_t area_id) { double mrgs; mrgs = (double) dm_stats_get_counter(dms, DM_STATS_READS_MERGED_COUNT, region_id, area_id); *rrqm = mrgs / (double) dms->interval_ns; return 1; } static int _wr_merges_per_sec(const struct dm_stats *dms, double *wrqm, uint64_t region_id, uint64_t area_id) { double mrgs; mrgs = (double) dm_stats_get_counter(dms, DM_STATS_WRITES_MERGED_COUNT, region_id, area_id); *wrqm = mrgs / (double) dms->interval_ns; return 1; } static int _reads_per_sec(const struct dm_stats *dms, double *rd_s, uint64_t region_id, uint64_t area_id) { double reads; reads = (double) dm_stats_get_counter(dms, DM_STATS_READS_COUNT, region_id, area_id); *rd_s = (reads * NSEC_PER_SEC) / (double) dms->interval_ns; return 1; } static int _writes_per_sec(const struct dm_stats *dms, double *wr_s, uint64_t region_id, uint64_t area_id) { double writes; writes = (double) dm_stats_get_counter(dms, DM_STATS_WRITES_COUNT, region_id, area_id); *wr_s = (writes * NSEC_PER_SEC) / (double) dms->interval_ns; return 1; } static int _read_sectors_per_sec(const struct dm_stats *dms, double *rsec_s, uint64_t region_id, uint64_t area_id) { double sect; sect = (double) dm_stats_get_counter(dms, DM_STATS_READ_SECTORS_COUNT, region_id, area_id); *rsec_s = (sect * (double) NSEC_PER_SEC) / (double) dms->interval_ns; return 1; } static int _write_sectors_per_sec(const struct dm_stats *dms, double *wsec_s, uint64_t region_id, uint64_t area_id) { double sect; sect = (double) dm_stats_get_counter(dms, DM_STATS_WRITE_SECTORS_COUNT, region_id, area_id); *wsec_s = (sect * (double) NSEC_PER_SEC) / (double) dms->interval_ns; return 1; } static int _average_request_size(const struct dm_stats *dms, double *arqsz, uint64_t region_id, uint64_t area_id) { double ios, sectors; ios = (double) (dm_stats_get_counter(dms, DM_STATS_READS_COUNT, region_id, area_id) + dm_stats_get_counter(dms, DM_STATS_WRITES_COUNT, region_id, area_id)); sectors = (double) (dm_stats_get_counter(dms, DM_STATS_READ_SECTORS_COUNT, region_id, area_id) + dm_stats_get_counter(dms, DM_STATS_WRITE_SECTORS_COUNT, region_id, area_id)); if (ios > 0.0) *arqsz = sectors / ios; else *arqsz = 0.0; return 1; } static int _average_queue_size(const struct dm_stats *dms, double *qusz, uint64_t region_id, uint64_t area_id) { double io_ticks; io_ticks = (double) dm_stats_get_counter(dms, DM_STATS_WEIGHTED_IO_NSECS, region_id, area_id); if (io_ticks > 0.0) *qusz = io_ticks / (double) dms->interval_ns; else *qusz = 0.0; return 1; } static int _average_wait_time(const struct dm_stats *dms, double *await, uint64_t region_id, uint64_t area_id) { uint64_t io_ticks, nr_ios; io_ticks = dm_stats_get_counter(dms, DM_STATS_READ_NSECS, region_id, area_id); io_ticks += dm_stats_get_counter(dms, DM_STATS_WRITE_NSECS, region_id, area_id); nr_ios = dm_stats_get_counter(dms, DM_STATS_READS_COUNT, region_id, area_id); nr_ios += dm_stats_get_counter(dms, DM_STATS_WRITES_COUNT, region_id, area_id); if (nr_ios > 0) *await = (double) io_ticks / (double) nr_ios; else *await = 0.0; return 1; } static int _average_rd_wait_time(const struct dm_stats *dms, double *await, uint64_t region_id, uint64_t area_id) { uint64_t rd_io_ticks, nr_rd_ios; rd_io_ticks = dm_stats_get_counter(dms, DM_STATS_READ_NSECS, region_id, area_id); nr_rd_ios = dm_stats_get_counter(dms, DM_STATS_READS_COUNT, region_id, area_id); /* * If rd_io_ticks is > 0 this should imply that nr_rd_ios is * also > 0 (unless a kernel bug exists). Test for both here * before using the IO count as a divisor (Coverity). */ if (rd_io_ticks > 0 && nr_rd_ios > 0) *await = (double) rd_io_ticks / (double) nr_rd_ios; else *await = 0.0; return 1; } static int _average_wr_wait_time(const struct dm_stats *dms, double *await, uint64_t region_id, uint64_t area_id) { uint64_t wr_io_ticks, nr_wr_ios; wr_io_ticks = dm_stats_get_counter(dms, DM_STATS_WRITE_NSECS, region_id, area_id); nr_wr_ios = dm_stats_get_counter(dms, DM_STATS_WRITES_COUNT, region_id, area_id); /* * If wr_io_ticks is > 0 this should imply that nr_wr_ios is * also > 0 (unless a kernel bug exists). Test for both here * before using the IO count as a divisor (Coverity). */ if (wr_io_ticks > 0 && nr_wr_ios > 0) *await = (double) wr_io_ticks / (double) nr_wr_ios; else *await = 0.0; return 1; } static int _throughput(const struct dm_stats *dms, double *tput, uint64_t region_id, uint64_t area_id) { uint64_t nr_ios; nr_ios = dm_stats_get_counter(dms, DM_STATS_READS_COUNT, region_id, area_id); nr_ios += dm_stats_get_counter(dms, DM_STATS_WRITES_COUNT, region_id, area_id); *tput = ((double) NSEC_PER_SEC * (double) nr_ios) / (double) (dms->interval_ns); return 1; } static int _utilization(const struct dm_stats *dms, double *util, uint64_t region_id, uint64_t area_id) { uint64_t io_nsecs, interval_ns = dms->interval_ns; /** * If io_nsec > interval_ns there is something wrong with the clock * for the last interval; do not allow a value > 100% utilization * to be passed to a dm_make_percent() call. We expect to see these * at startup if counters have not been cleared before the first read. * * A zero interval_ns is also an error since metrics cannot be * calculated without a defined interval - return zero and emit a * backtrace in this case. */ io_nsecs = dm_stats_get_counter(dms, DM_STATS_IO_NSECS, region_id, area_id); if (!interval_ns) { *util = 0.0; return_0; } io_nsecs = ((io_nsecs < interval_ns) ? io_nsecs : interval_ns); *util = (double) io_nsecs / (double) interval_ns; return 1; } static int _service_time(const struct dm_stats *dms, double *svctm, uint64_t region_id, uint64_t area_id) { double tput, util; if (!_throughput(dms, &tput, region_id, area_id)) return 0; if (!_utilization(dms, &util, region_id, area_id)) return 0; util *= 100; /* avoid NAN with zero counter values */ if ( (uint64_t) tput == 0 || (uint64_t) util == 0) { *svctm = 0.0; return 1; } *svctm = ((double) NSEC_PER_SEC * dm_percent_to_float(util)) / (100.0 * tput); return 1; } /* * Table in enum order: * DM_STATS_RD_MERGES_PER_SEC, * DM_STATS_WR_MERGES_PER_SEC, * DM_STATS_READS_PER_SEC, * DM_STATS_WRITES_PER_SEC, * DM_STATS_READ_SECTORS_PER_SEC, * DM_STATS_WRITE_SECTORS_PER_SEC, * DM_STATS_AVERAGE_REQUEST_SIZE, * DM_STATS_AVERAGE_QUEUE_SIZE, * DM_STATS_AVERAGE_WAIT_TIME, * DM_STATS_AVERAGE_RD_WAIT_TIME, * DM_STATS_AVERAGE_WR_WAIT_TIME * DM_STATS_SERVICE_TIME, * DM_STATS_THROUGHPUT, * DM_STATS_UTILIZATION * */ typedef int (*_metric_fn_t)(const struct dm_stats *, double *, uint64_t, uint64_t); _metric_fn_t _metrics[DM_STATS_NR_METRICS] = { _rd_merges_per_sec, _wr_merges_per_sec, _reads_per_sec, _writes_per_sec, _read_sectors_per_sec, _write_sectors_per_sec, _average_request_size, _average_queue_size, _average_wait_time, _average_rd_wait_time, _average_wr_wait_time, _service_time, _throughput, _utilization }; int dm_stats_get_metric(const struct dm_stats *dms, int metric, uint64_t region_id, uint64_t area_id, double *value) { if (!dms->interval_ns) return_0; /* * Decode DM_STATS_{REGION,AREA}_CURRENT here; counters will then * be returned for the actual current region and area. * * DM_STATS_WALK_GROUP is passed through to the counter methods - * aggregates for the group are returned and used to calculate * the metric for the group totals. */ region_id = (region_id == DM_STATS_REGION_CURRENT) ? dms->cur_region : region_id ; area_id = (area_id == DM_STATS_REGION_CURRENT) ? dms->cur_area : area_id ; if (metric < 0 || metric >= DM_STATS_NR_METRICS) { log_error("Attempt to read invalid metric: %d", metric); return 0; } return _metrics[metric](dms, value, region_id, area_id); } /** * Methods for accessing stats metrics. All methods share the * following naming scheme and prototype: * * uint64_t dm_stats_get_metric(struct dm_stats *, * int, int, * uint64_t, uint64_t, * double *v) * * Where the two integer arguments are the region_id and area_id * respectively. * * name is the name of the metric (lower case) * metric is the part of the enum name following DM_STATS_ (upper case) */ #define MK_STATS_GET_METRIC_FN(name, metric, meta) \ int dm_stats_get_ ## name(const struct dm_stats *dms, double *meta, \ uint64_t region_id, uint64_t area_id) \ { \ return dm_stats_get_metric(dms, DM_STATS_ ## metric, \ region_id, area_id, meta); \ } MK_STATS_GET_METRIC_FN(rd_merges_per_sec, RD_MERGES_PER_SEC, rrqm) MK_STATS_GET_METRIC_FN(wr_merges_per_sec, WR_MERGES_PER_SEC, wrqm) MK_STATS_GET_METRIC_FN(reads_per_sec, READS_PER_SEC, rd_s) MK_STATS_GET_METRIC_FN(writes_per_sec, WRITES_PER_SEC, wr_s) MK_STATS_GET_METRIC_FN(read_sectors_per_sec, READ_SECTORS_PER_SEC, rsec_s) MK_STATS_GET_METRIC_FN(write_sectors_per_sec, WRITE_SECTORS_PER_SEC, wsec_s) MK_STATS_GET_METRIC_FN(average_request_size, AVERAGE_REQUEST_SIZE, arqsz) MK_STATS_GET_METRIC_FN(average_queue_size, AVERAGE_QUEUE_SIZE, qusz) MK_STATS_GET_METRIC_FN(average_wait_time, AVERAGE_WAIT_TIME, await) MK_STATS_GET_METRIC_FN(average_rd_wait_time, AVERAGE_RD_WAIT_TIME, await) MK_STATS_GET_METRIC_FN(average_wr_wait_time, AVERAGE_WR_WAIT_TIME, await) MK_STATS_GET_METRIC_FN(service_time, SERVICE_TIME, svctm) MK_STATS_GET_METRIC_FN(throughput, THROUGHPUT, tput) /* * Utilization is an exception since it used the dm_percent_t type in the * original named function based interface: preserve this behaviour for * backwards compatibility with existing users. * * The same metric may be accessed as a double via the enum based metric * interface. */ int dm_stats_get_utilization(const struct dm_stats *dms, dm_percent_t *util, uint64_t region_id, uint64_t area_id) { double _util; if (!dm_stats_get_metric(dms, DM_STATS_UTILIZATION, region_id, area_id, &_util)) return_0; /* scale up utilization value in the range [0.00..1.00] */ *util = dm_make_percent(DM_PERCENT_1 * _util, DM_PERCENT_1); return 1; } void dm_stats_set_sampling_interval_ms(struct dm_stats *dms, uint64_t interval_ms) { /* All times use nsecs internally. */ dms->interval_ns = interval_ms * NSEC_PER_MSEC; } void dm_stats_set_sampling_interval_ns(struct dm_stats *dms, uint64_t interval_ns) { dms->interval_ns = interval_ns; } uint64_t dm_stats_get_sampling_interval_ms(const struct dm_stats *dms) { /* All times use nsecs internally. */ return (dms->interval_ns / NSEC_PER_MSEC); } uint64_t dm_stats_get_sampling_interval_ns(const struct dm_stats *dms) { /* All times use nsecs internally. */ return (dms->interval_ns); } int dm_stats_set_program_id(struct dm_stats *dms, int allow_empty, const char *program_id) { if (!allow_empty && (!program_id || !strlen(program_id))) { log_error("Empty program_id not permitted without " "allow_empty=1"); return 0; } if (!program_id) program_id = ""; dm_free(dms->program_id); if (!(dms->program_id = dm_strdup(program_id))) return_0; return 1; } uint64_t dm_stats_get_current_region(const struct dm_stats *dms) { return dms->cur_region; } uint64_t dm_stats_get_current_area(const struct dm_stats *dms) { return dms->cur_area & ~DM_STATS_WALK_ALL; } int dm_stats_get_region_start(const struct dm_stats *dms, uint64_t *start, uint64_t region_id) { if (!dms || !dms->regions) return_0; /* start is unchanged when aggregating areas */ if (region_id & DM_STATS_WALK_REGION) region_id &= ~DM_STATS_WALK_REGION; /* use start of first region as group start */ if (region_id & DM_STATS_WALK_GROUP) { if (region_id == DM_STATS_WALK_GROUP) region_id = dms->cur_group; else region_id &= ~DM_STATS_WALK_GROUP; } *start = dms->regions[region_id].start; return 1; } int dm_stats_get_region_len(const struct dm_stats *dms, uint64_t *len, uint64_t region_id) { uint64_t i; if (!dms || !dms->regions) return_0; *len = 0; /* length is unchanged when aggregating areas */ if (region_id & DM_STATS_WALK_REGION) region_id &= ~DM_STATS_WALK_REGION; if (region_id & DM_STATS_WALK_GROUP) { /* decode region / group ID */ if (region_id == DM_STATS_WALK_GROUP) region_id = dms->cur_group; else region_id &= ~DM_STATS_WALK_GROUP; /* use sum of region sizes as group size */ if (_stats_region_is_grouped(dms, region_id)) _foreach_group_region(dms, dms->cur_group, i) *len += dms->regions[i].len; else { log_error("Group ID " FMTu64 " does not exist", region_id); return 0; } } else *len = dms->regions[region_id].len; return 1; } int dm_stats_get_region_area_len(const struct dm_stats *dms, uint64_t *len, uint64_t region_id) { if (!dms || !dms->regions) return_0; /* groups are not subdivided - area size equals group size */ if (region_id & (DM_STATS_WALK_GROUP | DM_STATS_WALK_REGION)) /* get_region_len will decode region_id */ return dm_stats_get_region_len(dms, len, region_id); *len = dms->regions[region_id].step; return 1; } int dm_stats_get_current_region_start(const struct dm_stats *dms, uint64_t *start) { return dm_stats_get_region_start(dms, start, dms->cur_region); } int dm_stats_get_current_region_len(const struct dm_stats *dms, uint64_t *len) { return dm_stats_get_region_len(dms, len, dms->cur_region); } int dm_stats_get_current_region_area_len(const struct dm_stats *dms, uint64_t *step) { return dm_stats_get_region_area_len(dms, step, dms->cur_region); } int dm_stats_get_area_start(const struct dm_stats *dms, uint64_t *start, uint64_t region_id, uint64_t area_id) { struct dm_stats_region *region; if (!dms || !dms->regions) return_0; /* group or region area start equals region start */ if (region_id & (DM_STATS_WALK_GROUP | DM_STATS_WALK_REGION)) return dm_stats_get_region_start(dms, start, region_id); region = &dms->regions[region_id]; *start = region->start + region->step * area_id; return 1; } int dm_stats_get_area_offset(const struct dm_stats *dms, uint64_t *offset, uint64_t region_id, uint64_t area_id) { if (!dms || !dms->regions) return_0; /* no areas for groups or aggregate regions */ if (region_id & (DM_STATS_WALK_GROUP | DM_STATS_WALK_REGION)) *offset = 0; else *offset = dms->regions[region_id].step * area_id; return 1; } int dm_stats_get_current_area_start(const struct dm_stats *dms, uint64_t *start) { return dm_stats_get_area_start(dms, start, dms->cur_region, dms->cur_area); } int dm_stats_get_current_area_offset(const struct dm_stats *dms, uint64_t *offset) { return dm_stats_get_area_offset(dms, offset, dms->cur_region, dms->cur_area); } int dm_stats_get_current_area_len(const struct dm_stats *dms, uint64_t *len) { return dm_stats_get_region_area_len(dms, len, dms->cur_region); } const char *dm_stats_get_region_program_id(const struct dm_stats *dms, uint64_t region_id) { const char *program_id = NULL; if (region_id & DM_STATS_WALK_GROUP) return dms->program_id; if (region_id & DM_STATS_WALK_REGION) region_id &= ~DM_STATS_WALK_REGION; program_id = dms->regions[region_id].program_id; return (program_id) ? program_id : ""; } const char *dm_stats_get_region_aux_data(const struct dm_stats *dms, uint64_t region_id) { const char *aux_data = NULL; if (region_id & DM_STATS_WALK_GROUP) return ""; if (region_id & DM_STATS_WALK_REGION) region_id &= ~DM_STATS_WALK_REGION; aux_data = dms->regions[region_id].aux_data; return (aux_data) ? aux_data : "" ; } int dm_stats_set_alias(struct dm_stats *dms, uint64_t group_id, const char *alias) { struct dm_stats_group *group = NULL; const char *old_alias = NULL; if (!dms->regions || !dms->groups || !alias) return_0; if (!_stats_region_is_grouped(dms, group_id)) { log_error("Cannot set alias for ungrouped region ID " FMTu64, group_id); return 0; } if (group_id & DM_STATS_WALK_GROUP) { if (group_id == DM_STATS_WALK_GROUP) group_id = dms->cur_group; else group_id &= ~DM_STATS_WALK_GROUP; } if (group_id != dms->regions[group_id].group_id) { /* dm_stats_set_alias() must be called on the group ID. */ log_error("Cannot set alias for group member " FMTu64 ".", group_id); return 0; } group = &dms->groups[group_id]; old_alias = group->alias; group->alias = dm_strdup(alias); if (!group->alias) { log_error("Could not allocate memory for alias."); goto bad; } if (!_stats_set_aux(dms, group_id, dms->regions[group_id].aux_data)) { log_error("Could not set new aux_data"); goto bad; } dm_free((char *) old_alias); return 1; bad: dm_free((char *) group->alias); group->alias = old_alias; return 0; } const char *dm_stats_get_alias(const struct dm_stats *dms, uint64_t id) { const struct dm_stats_region *region; id = (id == DM_STATS_REGION_CURRENT) ? dms->cur_region : id; if (id & DM_STATS_WALK_GROUP) { if (id == DM_STATS_WALK_GROUP) id = dms->cur_group; else id &= ~DM_STATS_WALK_GROUP; } region = &dms->regions[id]; if (!_stats_region_is_grouped(dms, id) || !dms->groups[region->group_id].alias) return dms->name; return dms->groups[region->group_id].alias; } const char *dm_stats_get_current_region_program_id(const struct dm_stats *dms) { return dm_stats_get_region_program_id(dms, dms->cur_region); } const char *dm_stats_get_current_region_aux_data(const struct dm_stats *dms) { return dm_stats_get_region_aux_data(dms, dms->cur_region); } int dm_stats_get_region_precise_timestamps(const struct dm_stats *dms, uint64_t region_id) { struct dm_stats_region *region; if (region_id == DM_STATS_REGION_CURRENT) region_id = dms->cur_region; if (region_id == DM_STATS_WALK_GROUP) region_id = dms->cur_group; else if (region_id & DM_STATS_WALK_GROUP) region_id &= ~DM_STATS_WALK_GROUP; region = &dms->regions[region_id]; return region->timescale == 1; } int dm_stats_get_current_region_precise_timestamps(const struct dm_stats *dms) { return dm_stats_get_region_precise_timestamps(dms, DM_STATS_REGION_CURRENT); } /* * Histogram access methods. */ static void _sum_histogram_bins(const struct dm_stats *dms, struct dm_histogram *dmh_aggr, uint64_t region_id, uint64_t area_id) { struct dm_stats_region *region; struct dm_histogram_bin *bins; struct dm_histogram *dmh_cur; int bin; region = &dms->regions[region_id]; dmh_cur = region->counters[area_id].histogram; bins = dmh_aggr->bins; for (bin = 0; bin < dmh_aggr->nr_bins; bin++) bins[bin].count += dmh_cur->bins[bin].count; } /* * Create an aggregate histogram for a sub-divided region or a group. */ static struct dm_histogram *_aggregate_histogram(const struct dm_stats *dms, uint64_t region_id, uint64_t area_id) { struct dm_histogram *dmh_aggr, *dmh_cur, **dmh_cachep; uint64_t group_id = DM_STATS_GROUP_NOT_PRESENT; int bin, nr_bins, group = 1; size_t hist_size; if (area_id == DM_STATS_WALK_REGION) { /* region aggregation */ group = 0; if (!_stats_region_present(&dms->regions[region_id])) return_NULL; if (!dms->regions[region_id].bounds) return_NULL; if (!dms->regions[region_id].counters) return dms->regions[region_id].bounds; if (dms->regions[region_id].histogram) return dms->regions[region_id].histogram; dmh_cur = dms->regions[region_id].counters[0].histogram; dmh_cachep = &dms->regions[region_id].histogram; nr_bins = dms->regions[region_id].bounds->nr_bins; } else { /* group aggregation */ group_id = region_id; area_id = DM_STATS_WALK_GROUP; if (!_stats_group_id_present(dms, group_id)) return_NULL; if (!dms->regions[group_id].bounds) return_NULL; if (!dms->regions[group_id].counters) return dms->regions[group_id].bounds; if (dms->groups[group_id].histogram) return dms->groups[group_id].histogram; dmh_cur = dms->regions[group_id].counters[0].histogram; dmh_cachep = &dms->groups[group_id].histogram; nr_bins = dms->regions[group_id].bounds->nr_bins; } hist_size = sizeof(*dmh_aggr) + nr_bins * sizeof(struct dm_histogram_bin); if (!(dmh_aggr = dm_pool_zalloc(dms->hist_mem, hist_size))) { log_error("Could not allocate group histogram"); return 0; } dmh_aggr->nr_bins = dmh_cur->nr_bins; dmh_aggr->dms = dms; if (!group) _foreach_region_area(dms, region_id, area_id) { _sum_histogram_bins(dms, dmh_aggr, region_id, area_id); } else { _foreach_group_area(dms, group_id, region_id, area_id) { _sum_histogram_bins(dms, dmh_aggr, region_id, area_id); } } for (bin = 0; bin < nr_bins; bin++) { dmh_aggr->sum += dmh_aggr->bins[bin].count; dmh_aggr->bins[bin].upper = dmh_cur->bins[bin].upper; } /* cache aggregate histogram for subsequent access */ *dmh_cachep = dmh_aggr; return dmh_aggr; } struct dm_histogram *dm_stats_get_histogram(const struct dm_stats *dms, uint64_t region_id, uint64_t area_id) { int aggr = 0; if (region_id == DM_STATS_REGION_CURRENT) { region_id = dms->cur_region; if (region_id & DM_STATS_WALK_GROUP) { region_id = dms->cur_group; aggr = 1; } } else if (region_id & DM_STATS_WALK_GROUP) { region_id &= ~DM_STATS_WALK_GROUP; aggr = 1; } area_id = (area_id == DM_STATS_AREA_CURRENT) ? dms->cur_area : area_id ; if (area_id == DM_STATS_WALK_REGION) aggr = 1; if (aggr) return _aggregate_histogram(dms, region_id, area_id); if (region_id & DM_STATS_WALK_REGION) region_id &= ~DM_STATS_WALK_REGION; if (!dms->regions[region_id].counters) return dms->regions[region_id].bounds; return dms->regions[region_id].counters[area_id].histogram; } int dm_histogram_get_nr_bins(const struct dm_histogram *dmh) { return dmh->nr_bins; } uint64_t dm_histogram_get_bin_lower(const struct dm_histogram *dmh, int bin) { return (!bin) ? 0 : dmh->bins[bin - 1].upper; } uint64_t dm_histogram_get_bin_upper(const struct dm_histogram *dmh, int bin) { return dmh->bins[bin].upper; } uint64_t dm_histogram_get_bin_width(const struct dm_histogram *dmh, int bin) { uint64_t upper, lower; upper = dm_histogram_get_bin_upper(dmh, bin); lower = dm_histogram_get_bin_lower(dmh, bin); return (upper - lower); } uint64_t dm_histogram_get_bin_count(const struct dm_histogram *dmh, int bin) { return dmh->bins[bin].count; } uint64_t dm_histogram_get_sum(const struct dm_histogram *dmh) { return dmh->sum; } dm_percent_t dm_histogram_get_bin_percent(const struct dm_histogram *dmh, int bin) { uint64_t value = dm_histogram_get_bin_count(dmh, bin); uint64_t width = dm_histogram_get_bin_width(dmh, bin); uint64_t total = dm_histogram_get_sum(dmh); double val = (double) value; if (!total || !value || !width) return DM_PERCENT_0; return dm_make_percent((uint64_t) val, total); } /* * Histogram string helper functions: used to construct histogram and * bin boundary strings from numeric data. */ /* * Allocate an unbound histogram object with nr_bins bins. Only used * for histograms used to hold bounds values as arguments for calls to * dm_stats_create_region(). */ static struct dm_histogram *_alloc_dm_histogram(int nr_bins) { /* Allocate space for dm_histogram + nr_entries. */ size_t size = sizeof(struct dm_histogram) + (unsigned) nr_bins * sizeof(struct dm_histogram_bin); return dm_zalloc(size); } /* * Parse a histogram bounds string supplied by the user. The string * consists of a list of numbers, "n1,n2,n3,..." with optional 'ns', * 'us', 'ms', or 's' unit suffixes. * * The scale parameter indicates the timescale used for this region: one * for nanoscale resolution and NSEC_PER_MSEC for miliseconds. * * On return bounds contains a pointer to an array of uint64_t * histogram bounds values expressed in units of nanoseconds. */ struct dm_histogram *dm_histogram_bounds_from_string(const char *bounds_str) { static const char _valid_chars[] = "0123456789,muns"; uint64_t this_val = 0, mult = 1; const char *c, *v, *val_start; struct dm_histogram_bin *cur; struct dm_histogram *dmh; int nr_entries = 1; char *endptr; c = bounds_str; /* Count number of bounds entries. */ while(*c) if (*(c++) == ',') nr_entries++; c = bounds_str; if (!(dmh = _alloc_dm_histogram(nr_entries))) return_0; dmh->nr_bins = nr_entries; cur = dmh->bins; do { for (v = _valid_chars; *v; v++) if (*c == *v) break; if (!*v) { stack; goto badchar; } if (*c == ',') { log_error("Empty histogram bin not allowed: %s", bounds_str); goto bad; } else { val_start = c; endptr = NULL; this_val = strtoull(val_start, &endptr, 10); if (!endptr) { log_error("Could not parse histogram bound."); goto bad; } c = endptr; /* Advance to units, comma, or end. */ if (*c == 's') { mult = NSEC_PER_SEC; c++; /* Advance over 's'. */ } else if (*(c + 1) == 's') { if (*c == 'm') mult = NSEC_PER_MSEC; else if (*c == 'u') mult = NSEC_PER_USEC; else if (*c == 'n') mult = 1; else { stack; goto badchar; } c += 2; /* Advance over 'ms', 'us', or 'ns'. */ } else if (*c == ',') c++; else if (*c) { /* Expected ',' or NULL. */ stack; goto badchar; } if (*c == ',') c++; this_val *= mult; (cur++)->upper = this_val; } } while (*c); /* Bounds histograms have no owner. */ dmh->dms = NULL; dmh->region = NULL; return dmh; badchar: log_error("Invalid character in histogram: %c", *c); bad: dm_free(dmh); return NULL; } struct dm_histogram *dm_histogram_bounds_from_uint64(const uint64_t *bounds) { const uint64_t *entry = bounds; struct dm_histogram_bin *cur; struct dm_histogram *dmh; int nr_entries = 1; if (!bounds || !bounds[0]) { log_error("Could not parse empty histogram bounds array"); return 0; } /* Count number of bounds entries. */ while(*entry) if (*(++entry)) nr_entries++; entry = bounds; if (!(dmh = _alloc_dm_histogram(nr_entries))) return_0; dmh->nr_bins = nr_entries; cur = dmh->bins; while (*entry) (cur++)->upper = *(entry++); /* Bounds histograms have no owner. */ dmh->dms = NULL; dmh->region = NULL; return dmh; } void dm_histogram_bounds_destroy(struct dm_histogram *bounds) { if (!bounds) return; /* Bounds histograms are not bound to any handle or region. */ if (bounds->dms || bounds->region) { log_error("Freeing invalid histogram bounds pointer %p.", (void *) bounds); stack; } /* dm_free() expects a (void *). */ dm_free((void *) bounds); } /* * Scale a bounds value down from nanoseconds to the largest possible * whole unit suffix. */ static void _scale_bound_value_to_suffix(uint64_t *bound, const char **suffix) { *suffix = "ns"; if (!(*bound % NSEC_PER_SEC)) { *bound /= NSEC_PER_SEC; *suffix = "s"; } else if (!(*bound % NSEC_PER_MSEC)) { *bound /= NSEC_PER_MSEC; *suffix = "ms"; } else if (!(*bound % NSEC_PER_USEC)) { *bound /= NSEC_PER_USEC; *suffix = "us"; } } #define DM_HISTOGRAM_BOUNDS_MASK 0x30 #define BOUNDS_LEN 64 static int _make_bounds_string(char *buf, size_t size, uint64_t lower, uint64_t upper, int flags, int width) { char bound_buf[BOUNDS_LEN]; const char *l_suff = NULL; const char *u_suff = NULL; const char *sep = ""; int bounds = flags & DM_HISTOGRAM_BOUNDS_MASK; if (!bounds) return_0; *buf = '\0'; if (flags & DM_HISTOGRAM_SUFFIX) { _scale_bound_value_to_suffix(&lower, &l_suff); _scale_bound_value_to_suffix(&upper, &u_suff); } else l_suff = u_suff = ""; if (flags & DM_HISTOGRAM_VALUES) sep = ":"; if (bounds > DM_HISTOGRAM_BOUNDS_LOWER) { /* Handle infinite uppermost bound. */ if (upper == UINT64_MAX) { if (dm_snprintf(bound_buf, sizeof(bound_buf), ">" FMTu64 "%s", lower, l_suff) < 0) goto_out; /* Only display an 'upper' string for final bin. */ bounds = DM_HISTOGRAM_BOUNDS_UPPER; } else { if (dm_snprintf(bound_buf, sizeof(bound_buf), FMTu64 "%s", upper, u_suff) < 0) goto_out; } } else if (bounds == DM_HISTOGRAM_BOUNDS_LOWER) { if ((dm_snprintf(bound_buf, sizeof(bound_buf), FMTu64 "%s", lower, l_suff)) < 0) goto_out; } switch (bounds) { case DM_HISTOGRAM_BOUNDS_LOWER: case DM_HISTOGRAM_BOUNDS_UPPER: return dm_snprintf(buf, size, "%*s%s", width, bound_buf, sep); case DM_HISTOGRAM_BOUNDS_RANGE: return dm_snprintf(buf, size, FMTu64 "%s-%s%s", lower, l_suff, bound_buf, sep); } out: return 0; } #define BOUND_WIDTH_NOSUFFIX 10 /* 999999999 nsecs */ #define BOUND_WIDTH 6 /* bounds string up to 9999xs */ #define COUNT_WIDTH 6 /* count string: up to 9999 */ #define PERCENT_WIDTH 6 /* percent string : 0.00-100.00% */ #define DM_HISTOGRAM_VALUES_MASK 0x06 const char *dm_histogram_to_string(const struct dm_histogram *dmh, int bin, int width, int flags) { char buf[BOUNDS_LEN], bounds_buf[BOUNDS_LEN]; int minwidth, bounds, values, start, last; uint64_t lower, upper, val_u64; /* bounds of the current bin. */ /* Use the histogram pool for string building. */ struct dm_pool *mem = dmh->dms->hist_mem; const char *sep = ""; int bounds_width; ssize_t len = 0; float val_flt; bounds = flags & DM_HISTOGRAM_BOUNDS_MASK; values = flags & DM_HISTOGRAM_VALUES; if (bin < 0) { start = 0; last = dmh->nr_bins - 1; } else start = last = bin; minwidth = width; if (width < 0 || !values) width = minwidth = 0; /* no padding */ else if (flags & DM_HISTOGRAM_PERCENT) width = minwidth = (width) ? : PERCENT_WIDTH; else if (flags & DM_HISTOGRAM_VALUES) width = minwidth = (width) ? : COUNT_WIDTH; if (values && !width) sep = ":"; /* Set bounds string to the empty string. */ bounds_buf[0] = '\0'; if (!dm_pool_begin_object(mem, 64)) return_0; for (bin = start; bin <= last; bin++) { if (bounds) { /* Default bounds width depends on time suffixes. */ bounds_width = (!(flags & DM_HISTOGRAM_SUFFIX)) ? BOUND_WIDTH_NOSUFFIX : BOUND_WIDTH ; bounds_width = (!width) ? width : bounds_width; lower = dm_histogram_get_bin_lower(dmh, bin); upper = dm_histogram_get_bin_upper(dmh, bin); len = sizeof(bounds_buf); len = _make_bounds_string(bounds_buf, len, lower, upper, flags, bounds_width); /* * Comma separates "bounds: value" pairs unless * --noheadings is used. */ sep = (width || !values) ? "," : ":"; /* Adjust width by real bounds length if set. */ width -= (width) ? (len - (bounds_width + 1)) : 0; /* -ve width indicates specified width was overrun. */ width = (width > 0) ? width : 0; } if (bin == last) sep = ""; if (flags & DM_HISTOGRAM_PERCENT) { dm_percent_t pr; pr = dm_histogram_get_bin_percent(dmh, bin); val_flt = dm_percent_to_float(pr); len = dm_snprintf(buf, sizeof(buf), "%s%*.2f%%%s", bounds_buf, width, val_flt, sep); } else if (values) { val_u64 = dmh->bins[bin].count; len = dm_snprintf(buf, sizeof(buf), "%s%*"PRIu64"%s", bounds_buf, width, val_u64, sep); } else if (bounds) len = dm_snprintf(buf, sizeof(buf), "%s%s", bounds_buf, sep); else { *buf = '\0'; len = 0; } if (len < 0) goto_bad; width = minwidth; /* re-set histogram column width. */ if (!dm_pool_grow_object(mem, buf, (size_t) len)) goto_bad; } if (!dm_pool_grow_object(mem, "\0", 1)) goto_bad; return (const char *) dm_pool_end_object(mem); bad: dm_pool_abandon_object(mem); return NULL; } /* * A lightweight representation of an extent (region, area, file * system block or extent etc.). A table of extents can be used * to sort and to efficiently find holes or overlaps among a set * of tuples of the form (id, start, len). */ struct _extent { struct dm_list list; uint64_t id; uint64_t start; uint64_t len; }; /* last address in an extent */ #define _extent_end(a) ((a)->start + (a)->len - 1) /* a and b must be sorted by increasing start sector */ #define _extents_overlap(a, b) (_extent_end(a) > (b)->start) /* * Comparison function to sort extents in ascending start order. */ static int _extent_start_compare(const void *p1, const void *p2) { const struct _extent *r1, *r2; r1 = (const struct _extent *) p1; r2 = (const struct _extent *) p2; if (r1->start < r2->start) return -1; else if (r1->start == r2->start) return 0; return 1; } static int _stats_create_group(struct dm_stats *dms, dm_bitset_t regions, const char *alias, uint64_t *group_id) { struct dm_stats_group *group; *group_id = dm_bit_get_first(regions); /* group has no regions? */ if (*group_id == DM_STATS_GROUP_NOT_PRESENT) return_0; group = &dms->groups[*group_id]; if (group->regions) { log_error(INTERNAL_ERROR "Unexpected group state while" "creating group ID bitmap" FMTu64, *group_id); return 0; } group->group_id = *group_id; group->regions = regions; if (alias) group->alias = dm_strdup(alias); else group->alias = NULL; /* force an update of the group tag stored in aux_data */ if (!_stats_set_aux(dms, *group_id, dms->regions[*group_id].aux_data)) return 0; return 1; } static int _stats_group_check_overlap(const struct dm_stats *dms, dm_bitset_t regions, int count) { struct dm_list ext_list = DM_LIST_HEAD_INIT(ext_list); struct _extent *ext, *tmp, *next, *map = NULL; size_t map_size = (dms->max_region + 1) * sizeof(*map); int i = 0, id, overlap, merged; map = dm_pool_alloc(dms->mem, map_size); if (!map) { log_error("Could not allocate memory for region map"); return 0; } /* build a table of extents in order of region_id */ for (id = dm_bit_get_first(regions); id >= 0; id = dm_bit_get_next(regions, id)) { dm_list_init(&map[i].list); map[i].id = id; map[i].start = dms->regions[id].start; map[i].len = dms->regions[id].len; i++; } /* A single region cannot overlap itself. */ if (i == 1) { dm_pool_free(dms->mem, map); return 1; } /* sort by extent.start */ qsort(map, count, sizeof(*map), _extent_start_compare); for (i = 0; i < count; i++) dm_list_add(&ext_list, &map[i].list); overlap = 0; merge: merged = 0; dm_list_iterate_items_safe(ext, tmp, &ext_list) { next = dm_list_item(dm_list_next(&ext_list, &ext->list), struct _extent); if (!next) continue; if (_extents_overlap(ext, next)) { log_warn("WARNING: region IDs " FMTu64 " and " FMTu64 " overlap. Some events will be " "counted twice.", ext->id, next->id); /* merge larger extent into smaller */ if (_extent_end(ext) > _extent_end(next)) { next->id = ext->id; next->len = ext->len; } if (ext->start < next->start) next->start = ext->start; dm_list_del(&ext->list); overlap = merged = 1; } } /* continue until no merge candidates remain */ if (merged) goto merge; dm_pool_free(dms->mem, map); return (overlap == 0); } static void _stats_copy_histogram_bounds(struct dm_histogram *to, struct dm_histogram *from) { int i; to->nr_bins = from->nr_bins; for (i = 0; i < to->nr_bins; i++) to->bins[i].upper = from->bins[i].upper; } /* * Compare histogram bounds h1 and h2, and return 1 if they match (i.e. * have the same number of bins and identical bin boundary values), or 0 * otherwise. */ static int _stats_check_histogram_bounds(struct dm_histogram *h1, struct dm_histogram *h2) { int i; if (!h1 || !h2) return 0; if (h1->nr_bins != h2->nr_bins) return 0; for (i = 0; i < h1->nr_bins; i++) if (h1->bins[i].upper != h2->bins[i].upper) return 0; return 1; } /* * Create a new group in stats handle dms from the group description * passed in group. */ int dm_stats_create_group(struct dm_stats *dms, const char *members, const char *alias, uint64_t *group_id) { struct dm_histogram *check = NULL, *bounds; int i, count = 0, precise = 0; dm_bitset_t regions; if (!dms->regions || !dms->groups) { log_error("Could not create group: no regions found."); return 0; }; if (!(regions = dm_bitset_parse_list(members, NULL, 0))) { log_error("Could not parse list: '%s'", members); return 0; } if (!(check = dm_pool_zalloc(dms->hist_mem, sizeof(*check)))) { log_error("Could not allocate memory for bounds check"); goto bad; } /* too many bits? */ if ((*regions - 1) > dms->max_region) { log_error("Invalid region ID: %d", *regions - 1); goto bad; } /* * Check that each region_id in the bitmap meets the group * constraints: present, not already grouped, and if any * histogram is present that they all have the same bounds. */ for (i = dm_bit_get_first(regions); i >= 0; i = dm_bit_get_next(regions, i)) { if (!dm_stats_region_present(dms, i)) { log_error("Region ID %d does not exist", i); goto bad; } if (_stats_region_is_grouped(dms, i)) { log_error("Region ID %d already a member of group ID " FMTu64, i, dms->regions[i].group_id); goto bad; } if (dms->regions[i].timescale == 1) precise++; /* check for matching histogram bounds */ bounds = dms->regions[i].bounds; if (bounds && !check->nr_bins) _stats_copy_histogram_bounds(check, bounds); else if (bounds) { if (!_stats_check_histogram_bounds(check, bounds)) { log_error("All region histogram bounds " "must match exactly"); goto bad; } } count++; } if (precise && (precise != count)) log_warn("WARNING: Grouping regions with different clock resolution: " "precision may be lost."); if (!_stats_group_check_overlap(dms, regions, count)) log_very_verbose("Creating group with overlapping regions."); if (!_stats_create_group(dms, regions, alias, group_id)) goto bad; dm_pool_free(dms->hist_mem, check); return 1; bad: dm_pool_free(dms->hist_mem, check); dm_bitset_destroy(regions); return 0; } /* * Remove the specified group_id. */ int dm_stats_delete_group(struct dm_stats *dms, uint64_t group_id, int remove_regions) { struct dm_stats_region *leader; dm_bitset_t regions; uint64_t i; if (group_id > dms->max_region) { log_error("Invalid group ID: " FMTu64, group_id); return 0; } if (!_stats_group_id_present(dms, group_id)) { log_error("Group ID " FMTu64 " does not exist", group_id); return 0; } regions = dms->groups[group_id].regions; leader = &dms->regions[group_id]; /* delete all but the group leader */ for (i = (*regions - 1); i > leader->region_id; i--) { if (dm_bit(regions, i)) { dm_bit_clear(regions, i); if (remove_regions && !dm_stats_delete_region(dms, i)) log_warn("WARNING: Failed to delete region " FMTu64 " on %s.", i, dms->name); } } /* clear group and mark as not present */ _stats_clear_group_regions(dms, group_id); _stats_group_destroy(&dms->groups[group_id]); /* delete leader or clear aux_data */ if (remove_regions) return dm_stats_delete_region(dms, group_id); else if (!_stats_set_aux(dms, group_id, leader->aux_data)) return 0; return 1; } uint64_t dm_stats_get_group_id(const struct dm_stats *dms, uint64_t region_id) { region_id = (region_id == DM_STATS_REGION_CURRENT) ? dms->cur_region : region_id; if (region_id & DM_STATS_WALK_GROUP) { if (region_id == DM_STATS_WALK_GROUP) return dms->cur_group; else return region_id & ~DM_STATS_WALK_GROUP; } if (region_id & DM_STATS_WALK_REGION) region_id &= ~DM_STATS_WALK_REGION; return dms->regions[region_id].group_id; } int dm_stats_get_group_descriptor(const struct dm_stats *dms, uint64_t group_id, char **buf) { dm_bitset_t regions = dms->groups[group_id].regions; size_t buflen; buflen = _stats_group_tag_len(dms, regions); *buf = dm_pool_alloc(dms->mem, buflen); if (!*buf) { log_error("Could not allocate memory for regions string"); return 0; } if (!_stats_group_tag_fill(dms, regions, *buf, buflen)) return 0; return 1; } #ifdef HAVE_LINUX_FIEMAP_H /* * Resize the group bitmap corresponding to group_id so that it can * contain at least num_regions members. */ static int _stats_resize_group(struct dm_stats_group *group, uint64_t num_regions) { uint64_t last_bit = dm_bit_get_last(group->regions); dm_bitset_t new, old; if (last_bit >= num_regions) { log_error("Cannot resize group bitmap to " FMTu64 " with bit " FMTu64 " set.", num_regions, last_bit); return 0; } log_very_verbose("Resizing group bitmap from " FMTu32 " to " FMTu64 " (last_bit: " FMTu64 ").", group->regions[0], num_regions, last_bit); new = dm_bitset_create(NULL, (unsigned) num_regions); if (!new) { log_error("Could not allocate memory for new group bitmap."); return 0; } old = group->regions; dm_bit_copy(new, old); group->regions = new; dm_bitset_destroy(old); return 1; } /* * Group a table of region_ids corresponding to the extents of a file. */ static int _stats_group_file_regions(struct dm_stats *dms, uint64_t *region_ids, uint64_t count, const char *alias) { dm_bitset_t regions = dm_bitset_create(NULL, dms->nr_regions); uint64_t i, group_id = DM_STATS_GROUP_NOT_PRESENT; char *members = NULL; size_t buflen; if (!regions) { log_error("Cannot map file: failed to allocate group bitmap."); return 0; } for (i = 0; i < count; i++) dm_bit_set(regions, region_ids[i]); buflen = _stats_group_tag_len(dms, regions); members = dm_malloc(buflen); if (!members) { log_error("Cannot map file: failed to allocate group " "descriptor."); dm_bitset_destroy(regions); return 0; } if (!_stats_group_tag_fill(dms, regions, members, buflen)) goto bad; /* * overlaps should not be possible: overlapping file extents * returned by FIEMAP imply a kernel bug or a corrupt fs. */ if (!_stats_group_check_overlap(dms, regions, count)) log_very_verbose("Creating group with overlapping regions."); if (!_stats_create_group(dms, regions, alias, &group_id)) goto bad; dm_free(members); return 1; bad: dm_bitset_destroy(regions); dm_free(members); return 0; } static int _stats_add_file_extent(int fd, struct dm_pool *mem, uint64_t id, struct fiemap_extent *fm_ext) { struct _extent extent; /* final address of list is unknown */ memset(&extent.list, 0, sizeof(extent.list)); /* convert bytes to dm (512b) sectors */ extent.start = fm_ext->fe_physical >> SECTOR_SHIFT; extent.len = fm_ext->fe_length >> SECTOR_SHIFT; extent.id = id; log_very_verbose("Extent " FMTu64 " on fd %d at " FMTu64 "+" FMTu64, extent.id, fd, extent.start, extent.len); if (!dm_pool_grow_object(mem, &extent, sizeof(extent))) { log_error("Cannot map file: failed to grow extent map."); return 0; } return 1; } /* test for the boundary of an extent */ #define ext_boundary(ext, exp) \ ((ext).fe_logical != 0) && \ ((ext).fe_physical != (exp)) /* * Copy fields from fiemap_extent 'from' to the fiemap_extent * pointed to by 'to'. */ #define ext_copy(to, from) \ do { \ *(to) = *(from); \ } while (0) static uint64_t _stats_map_extents(int fd, struct dm_pool *mem, struct fiemap *fiemap, struct fiemap_extent *fm_ext, struct fiemap_extent *fm_last, struct fiemap_extent *fm_pending, uint64_t next_extent, int *eof) { uint64_t expected = 0, nr_extents = next_extent; unsigned int i; /* * Loop over the returned extents adding the fm_pending extent * to the table of extents each time a discontinuity (or eof) * is detected. * * We use a pointer to fm_pending in the caller since it is * possible that logical extents comprising a single physical * extent are returned by successive FIEMAP calls. */ for (i = 0; i < fiemap->fm_mapped_extents; i++) { expected = fm_last->fe_physical + fm_last->fe_length; if (fm_ext[i].fe_flags & FIEMAP_EXTENT_LAST) *eof = 1; /* cannot map extents that are not yet allocated. */ if (fm_ext[i].fe_flags & (FIEMAP_EXTENT_UNKNOWN | FIEMAP_EXTENT_DELALLOC)) continue; /* * Begin a new extent if the current physical address differs * from the expected address yielded by fm_last.fe_physical + * fm_last.fe_length. * * A logical discontinuity is seen at the start of the file if * unwritten space exists before the first extent: do not add * any extent record until we have accumulated a non-zero length * in fm_pending. */ if (fm_pending->fe_length && ext_boundary(fm_ext[i], expected)) { if (!_stats_add_file_extent(fd, mem, nr_extents, fm_pending)) goto_bad; nr_extents++; /* Begin a new pending extent. */ ext_copy(fm_pending, fm_ext + i); } else { expected = 0; /* Begin a new pending extent for extent 0. If there is * a hole at the start of the file, the first allocated * extent will have a non-zero fe_logical. Detect this * case by testing fm_pending->fe_length: if no length * has been accumulated we are handling the first * physical extent of the file. */ if (!fm_pending->fe_length || fm_ext[i].fe_logical == 0) ext_copy(fm_pending, fm_ext + i); else /* accumulate this logical extent's length */ fm_pending->fe_length += fm_ext[i].fe_length; } *fm_last = fm_ext[i]; } /* * If the file only has a single extent, no boundary is ever * detected to trigger addition of the first extent. */ if (*eof || (fm_ext[i - 1].fe_logical == 0)) { _stats_add_file_extent(fd, mem, nr_extents, fm_pending); nr_extents++; } fiemap->fm_start = (fm_ext[i - 1].fe_logical + fm_ext[i - 1].fe_length); /* return the number of extents found in this call. */ return nr_extents - next_extent; bad: /* signal mapping error to caller */ *eof = -1; return 0; } /* * Read the extents of an open file descriptor into a table of struct _extent. * * Based on e2fsprogs/misc/filefrag.c::filefrag_fiemap(). * * Copyright 2003 by Theodore Ts'o. * */ static struct _extent *_stats_get_extents_for_file(struct dm_pool *mem, int fd, uint64_t *count) { struct fiemap_extent fm_last = {0}, fm_pending = {0}, *fm_ext = NULL; struct fiemap *fiemap = NULL; int eof = 0, nr_extents = 0; struct _extent *extents; unsigned long flags = 0; uint64_t *buf; /* grow temporary extent table in the pool */ if (!dm_pool_begin_object(mem, sizeof(*extents))) return NULL; buf = dm_zalloc(STATS_FIE_BUF_LEN); if (!buf) { log_error("Could not allocate memory for FIEMAP buffer."); goto bad; } /* initialise pointers into the ioctl buffer. */ fiemap = (struct fiemap *) buf; fm_ext = &fiemap->fm_extents[0]; /* space available per ioctl */ *count = (STATS_FIE_BUF_LEN - sizeof(*fiemap)) / sizeof(struct fiemap_extent); flags = FIEMAP_FLAG_SYNC; do { /* start of ioctl loop - zero size and set count to bufsize */ fiemap->fm_length = ~0ULL; fiemap->fm_flags = flags; fiemap->fm_extent_count = *count; /* get count-sized chunk of extents */ if (ioctl(fd, FS_IOC_FIEMAP, (unsigned long) fiemap) < 0) { if (errno == EBADR) log_err_once("FIEMAP failed with unknown " "flags %x.", fiemap->fm_flags); goto bad; } /* If 0 extents are returned, more ioctls are not needed */ if (fiemap->fm_mapped_extents == 0) break; nr_extents += _stats_map_extents(fd, mem, fiemap, fm_ext, &fm_last, &fm_pending, nr_extents, &eof); /* check for extent mapping error */ if (eof < 0) goto bad; } while (eof == 0); if (!nr_extents) { log_error("Cannot map file: no allocated extents."); goto bad; } /* return total number of extents */ *count = nr_extents; extents = dm_pool_end_object(mem); /* free FIEMAP buffer. */ dm_free(buf); return extents; bad: *count = 0; dm_pool_abandon_object(mem); dm_free(buf); return NULL; } #define MATCH_EXTENT(e, s, l) \ (((e).start == (s)) && ((e).len == (l))) static struct _extent *_find_extent(uint64_t nr_extents, struct _extent *extents, uint64_t start, uint64_t len) { size_t i; for (i = 0; i < nr_extents; i++) if (MATCH_EXTENT(extents[i], start, len)) return extents + i; return NULL; } /* * Clean up a table of region_id values that were created during a * failed dm_stats_create_regions_from_fd, or dm_stats_update_regions_from_fd * operation. */ static void _stats_cleanup_region_ids(struct dm_stats *dms, uint64_t *regions, uint64_t nr_regions) { uint64_t i; for (i = 0; i < nr_regions; i++) if (!_stats_delete_region(dms, regions[i])) log_error("Could not delete region " FMTu64 ".", i); } /* * First update pass: prune no-longer-allocated extents from the group * and build a table of the remaining extents so that their creation * can be skipped in the second pass. */ static int _stats_unmap_regions(struct dm_stats *dms, uint64_t group_id, struct dm_pool *mem, struct _extent *extents, struct _extent **old_extents, uint64_t *count, int *regroup) { struct dm_stats_region *region = NULL; struct dm_stats_group *group = NULL; uint64_t nr_kept, nr_old; struct _extent ext; int64_t i; group = &dms->groups[group_id]; log_very_verbose("Checking for changed file extents in group ID " FMTu64, group_id); if (!dm_pool_begin_object(mem, sizeof(**old_extents))) { log_error("Could not allocate extent table."); return 0; } nr_kept = nr_old = 0; /* counts of old and retained extents */ /* * First pass: delete de-allocated extents and set regroup=1 if * deleting the current group leader. */ i = dm_bit_get_last(group->regions); for (; i >= 0; i = dm_bit_get_prev(group->regions, i)) { region = &dms->regions[i]; nr_old++; if (extents && _find_extent(*count, extents, region->start, region->len)) { ext.start = region->start; ext.len = region->len; ext.id = i; nr_kept++; if (!dm_pool_grow_object(mem, &ext, sizeof(ext))) goto out; log_very_verbose("Kept region " FMTu64, i); } else { if (i == group_id) *regroup = 1; if (!_stats_delete_region(dms, i)) { log_error("Could not remove region ID " FMTu64, i); goto out; } log_very_verbose("Deleted region " FMTu64, i); } } *old_extents = dm_pool_end_object(mem); if (!*old_extents) { log_error("Could not finalize region extent table."); goto out; } log_very_verbose("Kept " FMTd64 " of " FMTd64 " old extents", nr_kept, nr_old); log_very_verbose("Found " FMTu64 " new extents", *count - nr_kept); return (int) nr_kept; out: dm_pool_abandon_object(mem); return -1; } /* * Create or update a set of regions representing the extents of a file * and return a table of uint64_t region_id values. The number of regions * created is returned in the memory pointed to by count (which must be * non-NULL). * * If group_id is not equal to DM_STATS_GROUP_NOT_PRESENT, it is assumed * that group_id corresponds to a group containing existing regions that * were mapped to this file at an earlier time: regions will be added or * removed to reflect the current status of the file. */ static uint64_t *_stats_map_file_regions(struct dm_stats *dms, int fd, struct dm_histogram *bounds, int precise, uint64_t group_id, uint64_t *count, int *regroup) { struct _extent *extents = NULL, *old_extents = NULL; uint64_t *regions = NULL, fail_region, i, num_bits; struct dm_stats_group *group = NULL; struct dm_pool *extent_mem = NULL; struct _extent *old_ext; char *hist_arg = NULL; struct statfs fsbuf; int64_t nr_kept = 0; struct stat buf; int update; *count = 0; update = _stats_group_id_present(dms, group_id); #ifdef BTRFS_SUPER_MAGIC if (fstatfs(fd, &fsbuf)) { log_error("fstatfs failed for fd %d", fd); return 0; } if (fsbuf.f_type == BTRFS_SUPER_MAGIC) { log_error("Cannot map file: btrfs does not provide " "physical FIEMAP extent data."); return 0; } #endif if (fstat(fd, &buf)) { log_error("fstat failed for fd %d", fd); return 0; } if (!(buf.st_mode & S_IFREG)) { log_error("Not a regular file"); return 0; } if (!dm_is_dm_major(major(buf.st_dev))) { log_error("Cannot map file: not a device-mapper device."); return 0; } /* * If regroup is set here, we are creating a new filemap: otherwise * we are updating a group with a valid group identifier in group_id. */ if (update) log_very_verbose("Updating extents from fd %d with group ID " FMTu64 " on (%d:%d)", fd, group_id, major(buf.st_dev), minor(buf.st_dev)); else log_very_verbose("Mapping extents from fd %d on (%d:%d)", fd, major(buf.st_dev), minor(buf.st_dev)); /* Use a temporary, private pool for the extent table. This avoids * hijacking the dms->mem (region table) pool which would lead to * interleaving temporary allocations with dm_stats_list() data, * causing complications in the error path. */ if (!(extent_mem = dm_pool_create("extents", sizeof(*extents)))) return_NULL; if (!(extents = _stats_get_extents_for_file(extent_mem, fd, count))) { log_very_verbose("No extents found in fd %d", fd); if (!update) goto out; } if (update) { group = &dms->groups[group_id]; if ((nr_kept = _stats_unmap_regions(dms, group_id, extent_mem, extents, &old_extents, count, regroup)) < 0) goto_out; } if (bounds) if (!(hist_arg = _build_histogram_arg(bounds, &precise))) goto_out; /* make space for end-of-table marker */ if (!(regions = dm_malloc((1 + *count) * sizeof(*regions)))) { log_error("Could not allocate memory for region IDs."); goto_out; } /* * Second pass (first for non-update case): create regions for * all extents not retained from the prior mapping, and insert * retained regions into the table of region_id values. * * If a regroup is not scheduled, set group bits for newly * created regions in the group leader bitmap. */ for (i = 0; i < *count; i++) { if (update) { if ((old_ext = _find_extent((uint64_t) nr_kept, old_extents, extents[i].start, extents[i].len))) { regions[i] = old_ext->id; continue; } } if (!_stats_create_region(dms, regions + i, extents[i].start, extents[i].len, -1, precise, hist_arg, dms->program_id, "")) { log_error("Failed to create region " FMTu64 " of " FMTu64 " at " FMTu64 ".", i, *count, extents[i].start); goto out_remove; } log_very_verbose("Created new region mapping " FMTu64 "+" FMTu64 " with region ID " FMTu64, extents[i].start, extents[i].len, regions[i]); if (!*regroup && update) { /* expand group bitmap */ if (regions[i] > (group->regions[0] - 1)) { num_bits = regions[i] + *count; if (!_stats_resize_group(group, num_bits)) { log_error("Failed to resize group " "bitmap."); goto out_remove; } } dm_bit_set(group->regions, regions[i]); } } regions[*count] = DM_STATS_REGION_NOT_PRESENT; /* Update group leader aux_data for new group members. */ if (!*regroup && update) if (!_stats_set_aux(dms, group_id, dms->regions[group_id].aux_data)) log_error("Failed to update group aux_data."); if (bounds) dm_free(hist_arg); /* the extent table will be empty if the file has been truncated. */ if (extents) dm_pool_free(extent_mem, extents); dm_pool_destroy(extent_mem); return regions; out_remove: /* New region creation may begin to fail part-way through creating * a set of file mapped regions: in this case we need to roll back * the regions that were already created and return the handle to * a consistent state. A listed handle is required for this: use a * single list operation and call _stats_delete_region() directly * to avoid a @stats_list ioctl and list parsing for each region. */ if (!dm_stats_list(dms, NULL)) goto out; fail_region = i; _stats_cleanup_region_ids(dms, regions, fail_region); *count = 0; out: dm_pool_destroy(extent_mem); dm_free(hist_arg); dm_free(regions); return NULL; } uint64_t *dm_stats_create_regions_from_fd(struct dm_stats *dms, int fd, int group, int precise, struct dm_histogram *bounds, const char *alias) { uint64_t *regions, count; int regroup = 1; if (alias && !group) { log_error("Cannot set alias without grouping regions."); return NULL; } if (!(regions = _stats_map_file_regions(dms, fd, bounds, precise, DM_STATS_GROUP_NOT_PRESENT, &count, ®roup))) return NULL; if (!group) return regions; /* refresh handle */ if (!dm_stats_list(dms, NULL)) goto_out; if (!_stats_group_file_regions(dms, regions, count, alias)) goto_out; return regions; out: _stats_cleanup_region_ids(dms, regions, count); dm_free(regions); return NULL; } uint64_t *dm_stats_update_regions_from_fd(struct dm_stats *dms, int fd, uint64_t group_id) { struct dm_histogram *bounds = NULL; int nr_bins, precise, regroup; uint64_t *regions, count = 0; const char *alias = NULL; if (!dms->regions || !dm_stats_group_present(dms, group_id)) { if (!dm_stats_list(dms, dms->program_id)) { log_error("Could not obtain region list while " "updating group " FMTu64 ".", group_id); return NULL; } } if (!dm_stats_group_present(dms, group_id)) { log_error("Group ID " FMTu64 " does not exist.", group_id); return NULL; } /* * If the extent corresponding to the group leader's region has been * deallocated, _stats_map_file_regions() will remove the region and * the group. In this case, regroup will be set by the call and the * group will be re-created using saved values. */ regroup = 0; /* * A copy of the alias is needed to re-create the group when regroup=1. */ if (dms->groups[group_id].alias) { alias = dm_strdup(dms->groups[group_id].alias); if (!alias) { log_error("Failed to allocate group alias string."); return NULL; } } if (dms->regions[group_id].bounds) { /* * A copy of the histogram bounds must be passed to * _stats_map_file_regions() to be used when creating new * regions: it is not safe to use the copy in the current group * leader since it may be destroyed during the first group * update pass. */ nr_bins = dms->regions[group_id].bounds->nr_bins; bounds = _alloc_dm_histogram(nr_bins); if (!bounds) { log_error("Could not allocate memory for group " "histogram bounds."); goto out; } _stats_copy_histogram_bounds(bounds, dms->regions[group_id].bounds); } precise = (dms->regions[group_id].timescale == 1); regions = _stats_map_file_regions(dms, fd, bounds, precise, group_id, &count, ®roup); if (!regions) goto bad; if (!dm_stats_list(dms, NULL)) goto bad; /* regroup if there are regions to group */ if (regroup && (*regions != DM_STATS_REGION_NOT_PRESENT)) if (!_stats_group_file_regions(dms, regions, count, alias)) goto bad; dm_free(bounds); dm_free((char *) alias); return regions; bad: _stats_cleanup_region_ids(dms, regions, count); dm_free(bounds); dm_free(regions); out: dm_free((char *) alias); return NULL; } #else /* !HAVE_LINUX_FIEMAP */ uint64_t *dm_stats_create_regions_from_fd(struct dm_stats *dms, int fd, int group, int precise, struct dm_histogram *bounds, const char *alias) { log_error("File mapping requires FIEMAP ioctl support."); return 0; } uint64_t *dm_stats_update_regions_from_fd(struct dm_stats *dms, int fd, uint64_t group_id) { log_error("File mapping requires FIEMAP ioctl support."); return 0; } #endif /* HAVE_LINUX_FIEMAP */ #ifdef DMFILEMAPD static const char *_filemapd_mode_names[] = { "inode", "path", NULL }; dm_filemapd_mode_t dm_filemapd_mode_from_string(const char *mode_str) { dm_filemapd_mode_t mode = DM_FILEMAPD_FOLLOW_INODE; const char **mode_name; if (mode_str) { for (mode_name = _filemapd_mode_names; *mode_name; mode_name++) if (!strcmp(*mode_name, mode_str)) break; if (*mode_name) mode = DM_FILEMAPD_FOLLOW_INODE + (mode_name - _filemapd_mode_names); else { log_error("Could not parse dmfilemapd mode: %s", mode_str); return DM_FILEMAPD_FOLLOW_NONE; } } return mode; } #define DM_FILEMAPD "dmfilemapd" #define NR_FILEMAPD_ARGS 7 /* includes argv[0] */ /* * Start dmfilemapd to monitor the specified file descriptor, and to * update the group given by 'group_id' when the file's allocation * changes. * * usage: dmfilemapd [[]] */ int dm_stats_start_filemapd(int fd, uint64_t group_id, const char *path, dm_filemapd_mode_t mode, unsigned foreground, unsigned verbose) { char fd_str[8], group_str[8], fg_str[2], verb_str[2]; const char *mode_str = _filemapd_mode_names[mode]; char *args[NR_FILEMAPD_ARGS + 1]; pid_t pid = 0; int argc = 0; if (fd < 0) { log_error("dmfilemapd file descriptor must be " "non-negative: %d", fd); return 0; } if (path[0] != '/') { log_error("Path argument must specify an absolute path."); return 0; } if (mode > DM_FILEMAPD_FOLLOW_PATH) { log_error("Invalid dmfilemapd mode argument: " "Must be DM_FILEMAPD_FOLLOW_INODE or " "DM_FILEMAPD_FOLLOW_PATH"); return 0; } if (foreground > 1) { log_error("Invalid dmfilemapd foreground argument. " "Must be 0 or 1: %d.", foreground); return 0; } if (verbose > 3) { log_error("Invalid dmfilemapd verbose argument. " "Must be 0..3: %d.", verbose); return 0; } /* set argv[0] */ args[argc++] = (char *) DM_FILEMAPD; /* set */ if ((dm_snprintf(fd_str, sizeof(fd_str), "%d", fd)) < 0) { log_error("Could not format fd argument."); return 0; } args[argc++] = fd_str; /* set */ if ((dm_snprintf(group_str, sizeof(group_str), FMTu64, group_id)) < 0) { log_error("Could not format group_id argument."); return 0; } args[argc++] = group_str; /* set */ args[argc++] = (char *) path; /* set */ args[argc++] = (char *) mode_str; /* set */ if ((dm_snprintf(fg_str, sizeof(fg_str), "%u", foreground)) < 0) { log_error("Could not format foreground argument."); return 0; } args[argc++] = fg_str; /* set */ if ((dm_snprintf(verb_str, sizeof(verb_str), "%u", verbose)) < 0) { log_error("Could not format verbose argument."); return 0; } args[argc++] = verb_str; /* terminate args[argc] */ args[argc] = NULL; log_very_verbose("Spawning daemon as '%s %d " FMTu64 " %s %s %u %u'", *args, fd, group_id, path, mode_str, foreground, verbose); if (!foreground && ((pid = fork()) < 0)) { log_error("Failed to fork dmfilemapd process."); return 0; } if (pid > 0) { log_very_verbose("Forked dmfilemapd process as pid %d", pid); return 1; } execvp(args[0], args); log_sys_error("execvp", args[0]); if (!foreground) _exit(127); return 0; } # else /* !DMFILEMAPD */ dm_filemapd_mode_t dm_filemapd_mode_from_string(const char *mode_str) { return 0; }; int dm_stats_start_filemapd(int fd, uint64_t group_id, const char *path, dm_filemapd_mode_t mode, unsigned foreground, unsigned verbose) { log_error("dmfilemapd support disabled."); return 0; } #endif /* DMFILEMAPD */ /* * Backward compatible dm_stats_create_region() implementations. * * Keep these at the end of the file to avoid adding clutter around the * current dm_stats_create_region() version. */ #if defined(__GNUC__) int dm_stats_create_region_v1_02_106(struct dm_stats *dms, uint64_t *region_id, uint64_t start, uint64_t len, int64_t step, int precise, const char *program_id, const char *aux_data); int dm_stats_create_region_v1_02_106(struct dm_stats *dms, uint64_t *region_id, uint64_t start, uint64_t len, int64_t step, int precise, const char *program_id, const char *aux_data) { /* 1.02.106 lacks histogram argument. */ return _stats_create_region(dms, region_id, start, len, step, precise, NULL, program_id, aux_data); } DM_EXPORT_SYMBOL(dm_stats_create_region, 1_02_106); int dm_stats_create_region_v1_02_104(struct dm_stats *dms, uint64_t *region_id, uint64_t start, uint64_t len, int64_t step, const char *program_id, const char *aux_data); int dm_stats_create_region_v1_02_104(struct dm_stats *dms, uint64_t *region_id, uint64_t start, uint64_t len, int64_t step, const char *program_id, const char *aux_data) { /* 1.02.104 lacks histogram and precise arguments. */ return _stats_create_region(dms, region_id, start, len, step, 0, NULL, program_id, aux_data); } DM_EXPORT_SYMBOL(dm_stats_create_region, 1_02_104); #endif