Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-11-24 05:02:12 +00:00
Code Issues Packages Projects Releases Wiki Activity

perf tools: Introduce 'P' modifier to request max precision

Browse Source 
The 'P' will cause the event to get maximum possible detected precise
level.

Following record:
  $ perf record -e cycles:P ...

will detect maximum precise level for 'cycles' event and use it.

Commiter note:

Testing it:

  $ perf record -e cycles:P usleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.013 MB perf.data (9 samples) ]
  $ perf evlist
  cycles:P
  $ perf evlist -v
  cycles:P: size: 112, { sample_period, sample_freq }: 4000, sample_type:
  IP|TID|TIME|PERIOD, disabled: 1, inherit: 1, mmap: 1, comm: 1, freq: 1,
  enable_on_exec: 1, task: 1, precise_ip: 2, sample_id_all: 1, mmap2: 1,
  comm_exec: 1
  $

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Don Zickus <dzickus@redhat.com>
Cc: Kan Liang <kan.liang@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1444068369-20978-6-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This commit is contained in:
Jiri Olsa 2015-10-05 20:06:05 +02:00 committed by Arnaldo Carvalho de Melo
parent 45cf6c33f9
commit 7f94af7a48
5 changed files with 13 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
tools/perf/Documentation/perf-list.txt
View File

@ -30,6 +30,7 @@ counted. The following modifiers exist:
G - guest counting (in KVM guests)
H - host counting (not in KVM guests)
p - precise level
P - use maximum detected precise level
S - read sample value (PERF_SAMPLE_READ)
D - pin the event to the PMU

3
tools/perf/util/evsel.c
View File

@ -882,6 +882,9 @@ void perf_evsel__config(struct perf_evsel *evsel, struct record_opts *opts)
attr->clockid = opts->clockid;
}
if (evsel->precise_max)
perf_event_attr__set_max_precise_ip(attr);
/*
* Apply event specific term settings,
* it overloads any global configuration.

1
tools/perf/util/evsel.h
View File

@ -111,6 +111,7 @@ struct perf_evsel {
bool system_wide;
bool tracking;
bool per_pkg;
bool precise_max;
/* parse modifier helper */
int exclude_GH;
int nr_members;

8
tools/perf/util/parse-events.c
View File

@ -923,6 +923,7 @@ struct event_modifier {
int eG;
int eI;
int precise;
int precise_max;
int exclude_GH;
int sample_read;
int pinned;
@ -938,6 +939,7 @@ static int get_event_modifier(struct event_modifier *mod, char *str,
int eG = evsel ? evsel->attr.exclude_guest : 0;
int eI = evsel ? evsel->attr.exclude_idle : 0;
int precise = evsel ? evsel->attr.precise_ip : 0;
int precise_max = 0;
int sample_read = 0;
int pinned = evsel ? evsel->attr.pinned : 0;
@ -974,6 +976,8 @@ static int get_event_modifier(struct event_modifier *mod, char *str,
/* use of precise requires exclude_guest */
if (!exclude_GH)
eG = 1;
} else if (*str == 'P') {
precise_max = 1;
} else if (*str == 'S') {
sample_read = 1;
} else if (*str == 'D') {
@ -1004,6 +1008,7 @@ static int get_event_modifier(struct event_modifier *mod, char *str,
mod->eG = eG;
mod->eI = eI;
mod->precise = precise;
mod->precise_max = precise_max;
mod->exclude_GH = exclude_GH;
mod->sample_read = sample_read;
mod->pinned = pinned;
@ -1020,7 +1025,7 @@ static int check_modifier(char *str)
char *p = str;
/* The sizeof includes 0 byte as well. */
if (strlen(str) > (sizeof("ukhGHpppSDI") - 1))
if (strlen(str) > (sizeof("ukhGHpppPSDI") - 1))
return -1;
while (*p) {
@ -1059,6 +1064,7 @@ int parse_events__modifier_event(struct list_head *list, char *str, bool add)
evsel->attr.exclude_idle = mod.eI;
evsel->exclude_GH = mod.exclude_GH;
evsel->sample_read = mod.sample_read;
evsel->precise_max = mod.precise_max;
if (perf_evsel__is_group_leader(evsel))
evsel->attr.pinned = mod.pinned;

2
tools/perf/util/parse-events.l
View File

@ -122,7 +122,7 @@ num_raw_hex [a-fA-F0-9]+
name [a-zA-Z_*?][a-zA-Z0-9_*?.]*
name_minus [a-zA-Z_*?][a-zA-Z0-9\-_*?.]*
/* If you add a modifier you need to update check_modifier() */
modifier_event [ukhpGHSDI]+
modifier_event [ukhpPGHSDI]+
modifier_bp [rwx]{1,3}
%%