From 0b77383134f3dbb461189a9c4f3b46b20152045d Mon Sep 17 00:00:00 2001 From: Alexey Budankov Date: Tue, 6 Nov 2018 12:03:35 +0300 Subject: [PATCH] perf mmap: Map data buffer for preserving collected data The map->data buffer is used to preserve map->base profiling data for writing to disk. AIO map->cblock is used to queue corresponding map->data buffer for asynchronous writing. Signed-off-by: Alexey Budankov Reviewed-by: Jiri Olsa Acked-by: Namhyung Kim Cc: Alexander Shishkin Cc: Andi Kleen Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/5fcda10c-6c63-68df-383a-c6d9e5d1f918@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/evlist.c | 2 +- tools/perf/util/mmap.c | 49 +++++++++++++++++++++++++++++++++++++++- tools/perf/util/mmap.h | 11 ++++++++- 3 files changed, 59 insertions(+), 3 deletions(-) diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c index 36526d229315..6f010b9f0a81 100644 --- a/tools/perf/util/evlist.c +++ b/tools/perf/util/evlist.c @@ -1028,7 +1028,7 @@ int perf_evlist__mmap_ex(struct perf_evlist *evlist, unsigned int pages, * Its value is decided by evsel's write_backward. * So &mp should not be passed through const pointer. */ - struct mmap_params mp; + struct mmap_params mp = { .nr_cblocks = 0 }; if (!evlist->mmap) evlist->mmap = perf_evlist__alloc_mmap(evlist, false); diff --git a/tools/perf/util/mmap.c b/tools/perf/util/mmap.c index cdb95b3a1213..47cdc3ad6546 100644 --- a/tools/perf/util/mmap.c +++ b/tools/perf/util/mmap.c @@ -153,8 +153,55 @@ void __weak auxtrace_mmap_params__set_idx(struct auxtrace_mmap_params *mp __mayb { } +#ifdef HAVE_AIO_SUPPORT +static int perf_mmap__aio_mmap(struct perf_mmap *map, struct mmap_params *mp) +{ + int delta_max; + + if (mp->nr_cblocks) { + map->aio.data = malloc(perf_mmap__mmap_len(map)); + if (!map->aio.data) { + pr_debug2("failed to allocate data buffer, error %m\n"); + return -1; + } + /* + * Use cblock.aio_fildes value different from -1 + * to denote started aio write operation on the + * cblock so it requires explicit record__aio_sync() + * call prior the cblock may be reused again. + */ + map->aio.cblock.aio_fildes = -1; + /* + * Allocate cblock with max priority delta to + * have faster aio write system calls. + */ + delta_max = sysconf(_SC_AIO_PRIO_DELTA_MAX); + map->aio.cblock.aio_reqprio = delta_max; + } + + return 0; +} + +static void perf_mmap__aio_munmap(struct perf_mmap *map) +{ + if (map->aio.data) + zfree(&map->aio.data); +} +#else +static int perf_mmap__aio_mmap(struct perf_mmap *map __maybe_unused, + struct mmap_params *mp __maybe_unused) +{ + return 0; +} + +static void perf_mmap__aio_munmap(struct perf_mmap *map __maybe_unused) +{ +} +#endif + void perf_mmap__munmap(struct perf_mmap *map) { + perf_mmap__aio_munmap(map); if (map->base != NULL) { munmap(map->base, perf_mmap__mmap_len(map)); map->base = NULL; @@ -197,7 +244,7 @@ int perf_mmap__mmap(struct perf_mmap *map, struct mmap_params *mp, int fd, int c &mp->auxtrace_mp, map->base, fd)) return -1; - return 0; + return perf_mmap__aio_mmap(map, mp); } static int overwrite_rb_find_range(void *buf, int mask, u64 *start, u64 *end) diff --git a/tools/perf/util/mmap.h b/tools/perf/util/mmap.h index cc5e2d6d17a9..3f10ad030c5e 100644 --- a/tools/perf/util/mmap.h +++ b/tools/perf/util/mmap.h @@ -6,6 +6,9 @@ #include #include #include +#ifdef HAVE_AIO_SUPPORT +#include +#endif #include "auxtrace.h" #include "event.h" @@ -26,6 +29,12 @@ struct perf_mmap { bool overwrite; struct auxtrace_mmap auxtrace_mmap; char event_copy[PERF_SAMPLE_MAX_SIZE] __aligned(8); +#ifdef HAVE_AIO_SUPPORT + struct { + void *data; + struct aiocb cblock; + } aio; +#endif }; /* @@ -57,7 +66,7 @@ enum bkw_mmap_state { }; struct mmap_params { - int prot, mask; + int prot, mask, nr_cblocks; struct auxtrace_mmap_params auxtrace_mp; };