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perf trace: Add support for pagefault tracing

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This patch adds optional pagefault tracing support to 'perf trace'.

Using -F/--pf option user can specify whether he wants minor, major or
all pagefault events to be traced. This patch adds only live mode,
record and replace will come in a separate patch.

Example output:

  1756272.905 ( 0.000 ms): curl/5937 majfault [0x7fa7261978b6] => /usr/lib/x86_64-linux-gnu/libkrb5.so.26.0.0@0x85288 (d.)
  1862866.036 ( 0.000 ms): wget/8460 majfault [__clear_user+0x3f] => 0x659cb4 (?k)

Signed-off-by: Stanislav Fomichev <stfomichev@yandex-team.ru>
Cc: David Ahern <dsahern@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1403799268-1367-3-git-send-email-stfomichev@yandex-team.ru
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Stanislav Fomichev 2014-06-26 20:14:25 +04:00 committed by Arnaldo Carvalho de Melo
parent 0c82adcf14
commit 598d02c5a0
2 changed files with 163 additions and 1 deletions
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39
tools/perf/Documentation/perf-trace.txt
View File

@ -107,6 +107,45 @@ the thread executes on the designated CPUs. Default is to monitor all CPUs.
Show tool stats such as number of times fd->pathname was discovered thru
hooking the open syscall return + vfs_getname or via reading /proc/pid/fd, etc.
-F=[all|min|maj]::
--pf=[all|min|maj]::
Trace pagefaults. Optionally, you can specify whether you want minor,
major or all pagefaults. Default value is maj.
PAGEFAULTS
----------
When tracing pagefaults, the format of the trace is as follows:
<min|maj>fault [<ip.symbol>+<ip.offset>] => <addr.dso@addr.offset> (<map type><addr level>).
- min/maj indicates whether fault event is minor or major;
- ip.symbol shows symbol for instruction pointer (the code that generated the
fault); if no debug symbols available, perf trace will print raw IP;
- addr.dso shows DSO for the faulted address;
- map type is either 'd' for non-executable maps or 'x' for executable maps;
- addr level is either 'k' for kernel dso or '.' for user dso.
For symbols resolution you may need to install debugging symbols.
Please be aware that duration is currently always 0 and doesn't reflect actual
time it took for fault to be handled!
When --verbose specified, perf trace tries to print all available information
for both IP and fault address in the form of dso@symbol+offset.
EXAMPLES
--------
Trace syscalls, major and minor pagefaults:
$ perf trace -F all
1416.547 ( 0.000 ms): python/20235 majfault [CRYPTO_push_info_+0x0] => /lib/x86_64-linux-gnu/libcrypto.so.1.0.0@0x61be0 (x.)
As you can see, there was major pagefault in python process, from
CRYPTO_push_info_ routine which faulted somewhere in libcrypto.so.
SEE ALSO
--------
linkperf:perf-record[1], linkperf:perf-script[1]

125
tools/perf/builtin-trace.c
View File

@ -1178,6 +1178,9 @@ fail:
return NULL;
}
#define TRACE_PFMAJ (1 << 0)
#define TRACE_PFMIN (1 << 1)
struct trace {
struct perf_tool tool;
struct {
@ -1212,6 +1215,7 @@ struct trace {
bool summary_only;
bool show_comm;
bool show_tool_stats;
int trace_pgfaults;
};
static int trace__set_fd_pathname(struct thread *thread, int fd, const char *pathname)
@ -1773,6 +1777,68 @@ out_dump:
return 0;
}
static void print_location(FILE *f, struct perf_sample *sample,
struct addr_location *al,
bool print_dso, bool print_sym)
{
if ((verbose || print_dso) && al->map)
fprintf(f, "%s@", al->map->dso->long_name);
if ((verbose || print_sym) && al->sym)
fprintf(f, "%s+0x%lx", al->sym->name,
al->addr - al->sym->start);
else if (al->map)
fprintf(f, "0x%lx", al->addr);
else
fprintf(f, "0x%lx", sample->addr);
}
static int trace__pgfault(struct trace *trace,
struct perf_evsel *evsel,
union perf_event *event,
struct perf_sample *sample)
{
struct thread *thread;
u8 cpumode = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
struct addr_location al;
char map_type = 'd';
thread = machine__findnew_thread(trace->host, sample->pid, sample->tid);
thread__find_addr_location(thread, trace->host, cpumode, MAP__FUNCTION,
sample->ip, &al);
trace__fprintf_entry_head(trace, thread, 0, sample->time, trace->output);
fprintf(trace->output, "%sfault [",
evsel->attr.config == PERF_COUNT_SW_PAGE_FAULTS_MAJ ?
"maj" : "min");
print_location(trace->output, sample, &al, false, true);
fprintf(trace->output, "] => ");
thread__find_addr_location(thread, trace->host, cpumode, MAP__VARIABLE,
sample->addr, &al);
if (!al.map) {
thread__find_addr_location(thread, trace->host, cpumode,
MAP__FUNCTION, sample->addr, &al);
if (al.map)
map_type = 'x';
else
map_type = '?';
}
print_location(trace->output, sample, &al, true, false);
fprintf(trace->output, " (%c%c)\n", map_type, al.level);
return 0;
}
static bool skip_sample(struct trace *trace, struct perf_sample *sample)
{
if ((trace->pid_list && intlist__find(trace->pid_list, sample->pid)) ||
@ -1887,6 +1953,30 @@ static void perf_evlist__add_vfs_getname(struct perf_evlist *evlist)
perf_evlist__add(evlist, evsel);
}
static int perf_evlist__add_pgfault(struct perf_evlist *evlist,
u64 config)
{
struct perf_evsel *evsel;
struct perf_event_attr attr = {
.type = PERF_TYPE_SOFTWARE,
.mmap_data = 1,
.sample_period = 1,
};
attr.config = config;
event_attr_init(&attr);
evsel = perf_evsel__new(&attr);
if (!evsel)
return -ENOMEM;
evsel->handler = trace__pgfault;
perf_evlist__add(evlist, evsel);
return 0;
}
static int trace__run(struct trace *trace, int argc, const char **argv)
{
struct perf_evlist *evlist = perf_evlist__new();
@ -1907,6 +1997,14 @@ static int trace__run(struct trace *trace, int argc, const char **argv)
perf_evlist__add_vfs_getname(evlist);
if ((trace->trace_pgfaults & TRACE_PFMAJ) &&
perf_evlist__add_pgfault(evlist, PERF_COUNT_SW_PAGE_FAULTS_MAJ))
goto out_error_tp;
if ((trace->trace_pgfaults & TRACE_PFMIN) &&
perf_evlist__add_pgfault(evlist, PERF_COUNT_SW_PAGE_FAULTS_MIN))
goto out_error_tp;
if (trace->sched &&
perf_evlist__add_newtp(evlist, "sched", "sched_stat_runtime",
trace__sched_stat_runtime))
@ -1987,7 +2085,8 @@ again:
goto next_event;
}
if (sample.raw_data == NULL) {
if (evsel->attr.type == PERF_TYPE_TRACEPOINT &&
sample.raw_data == NULL) {
fprintf(trace->output, "%s sample with no payload for tid: %d, cpu %d, raw_size=%d, skipping...\n",
perf_evsel__name(evsel), sample.tid,
sample.cpu, sample.raw_size);
@ -2269,6 +2368,23 @@ static int trace__open_output(struct trace *trace, const char *filename)
return trace->output == NULL ? -errno : 0;
}
static int parse_pagefaults(const struct option *opt, const char *str,
int unset __maybe_unused)
{
int *trace_pgfaults = opt->value;
if (strcmp(str, "all") == 0)
*trace_pgfaults |= TRACE_PFMAJ | TRACE_PFMIN;
else if (strcmp(str, "maj") == 0)
*trace_pgfaults |= TRACE_PFMAJ;
else if (strcmp(str, "min") == 0)
*trace_pgfaults |= TRACE_PFMIN;
else
return -1;
return 0;
}
int cmd_trace(int argc, const char **argv, const char *prefix __maybe_unused)
{
const char * const trace_usage[] = {
@ -2335,6 +2451,8 @@ int cmd_trace(int argc, const char **argv, const char *prefix __maybe_unused)
"Show only syscall summary with statistics"),
OPT_BOOLEAN('S', "with-summary", &trace.summary,
"Show all syscalls and summary with statistics"),
OPT_CALLBACK_DEFAULT('F', "pf", &trace.trace_pgfaults, "all|maj|min",
"Trace pagefaults", parse_pagefaults, "maj"),
OPT_END()
};
int err;
@ -2349,6 +2467,11 @@ int cmd_trace(int argc, const char **argv, const char *prefix __maybe_unused)
if (trace.summary_only)
trace.summary = trace.summary_only;
if (trace.trace_pgfaults) {
trace.opts.sample_address = true;
trace.opts.sample_time = true;
}
if (output_name != NULL) {
err = trace__open_output(&trace, output_name);
if (err < 0) {