diff --git a/tools/perf/Documentation/perf-list.txt b/tools/perf/Documentation/perf-list.txt index 826f3d6d1d28..eb03f063f0a2 100644 --- a/tools/perf/Documentation/perf-list.txt +++ b/tools/perf/Documentation/perf-list.txt @@ -29,6 +29,7 @@ counted. The following modifiers exist: G - guest counting (in KVM guests) H - host counting (not in KVM guests) p - precise level + S - read sample value (PERF_SAMPLE_READ) The 'p' modifier can be used for specifying how precise the instruction address should be. The 'p' modifier can be specified multiple times: diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c index 9ab8fff74e30..8f1016186d57 100644 --- a/tools/perf/util/evsel.c +++ b/tools/perf/util/evsel.c @@ -490,6 +490,7 @@ int perf_evsel__group_desc(struct perf_evsel *evsel, char *buf, size_t size) void perf_evsel__config(struct perf_evsel *evsel, struct perf_record_opts *opts) { + struct perf_evsel *leader = evsel->leader; struct perf_event_attr *attr = &evsel->attr; int track = !evsel->idx; /* only the first counter needs these */ @@ -499,6 +500,25 @@ void perf_evsel__config(struct perf_evsel *evsel, perf_evsel__set_sample_bit(evsel, IP); perf_evsel__set_sample_bit(evsel, TID); + if (evsel->sample_read) { + perf_evsel__set_sample_bit(evsel, READ); + + /* + * We need ID even in case of single event, because + * PERF_SAMPLE_READ process ID specific data. + */ + perf_evsel__set_sample_id(evsel); + + /* + * Apply group format only if we belong to group + * with more than one members. + */ + if (leader->nr_members > 1) { + attr->read_format |= PERF_FORMAT_GROUP; + attr->inherit = 0; + } + } + /* * We default some events to a 1 default interval. But keep * it a weak assumption overridable by the user. @@ -514,6 +534,15 @@ void perf_evsel__config(struct perf_evsel *evsel, } } + /* + * Disable sampling for all group members other + * than leader in case leader 'leads' the sampling. + */ + if ((leader != evsel) && leader->sample_read) { + attr->sample_freq = 0; + attr->sample_period = 0; + } + if (opts->no_samples) attr->sample_freq = 0; diff --git a/tools/perf/util/evsel.h b/tools/perf/util/evsel.h index 6a2cf261f38e..5edc625b6ecd 100644 --- a/tools/perf/util/evsel.h +++ b/tools/perf/util/evsel.h @@ -79,6 +79,7 @@ struct perf_evsel { /* parse modifier helper */ int exclude_GH; int nr_members; + int sample_read; struct perf_evsel *leader; char *group_name; }; diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c index 2c460ede0a69..dba877dc9482 100644 --- a/tools/perf/util/parse-events.c +++ b/tools/perf/util/parse-events.c @@ -687,6 +687,7 @@ struct event_modifier { int eG; int precise; int exclude_GH; + int sample_read; }; static int get_event_modifier(struct event_modifier *mod, char *str, @@ -698,6 +699,7 @@ static int get_event_modifier(struct event_modifier *mod, char *str, int eH = evsel ? evsel->attr.exclude_host : 0; int eG = evsel ? evsel->attr.exclude_guest : 0; int precise = evsel ? evsel->attr.precise_ip : 0; + int sample_read = 0; int exclude = eu | ek | eh; int exclude_GH = evsel ? evsel->exclude_GH : 0; @@ -730,6 +732,8 @@ 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 == 'S') { + sample_read = 1; } else break; @@ -756,6 +760,7 @@ static int get_event_modifier(struct event_modifier *mod, char *str, mod->eG = eG; mod->precise = precise; mod->exclude_GH = exclude_GH; + mod->sample_read = sample_read; return 0; } @@ -768,7 +773,7 @@ static int check_modifier(char *str) char *p = str; /* The sizeof includes 0 byte as well. */ - if (strlen(str) > (sizeof("ukhGHppp") - 1)) + if (strlen(str) > (sizeof("ukhGHpppS") - 1)) return -1; while (*p) { @@ -806,6 +811,7 @@ int parse_events__modifier_event(struct list_head *list, char *str, bool add) evsel->attr.exclude_host = mod.eH; evsel->attr.exclude_guest = mod.eG; evsel->exclude_GH = mod.exclude_GH; + evsel->sample_read = mod.sample_read; } return 0; diff --git a/tools/perf/util/parse-events.l b/tools/perf/util/parse-events.l index e9d1134c2c68..b36115fe416a 100644 --- a/tools/perf/util/parse-events.l +++ b/tools/perf/util/parse-events.l @@ -82,7 +82,7 @@ num_hex 0x[a-fA-F0-9]+ num_raw_hex [a-fA-F0-9]+ name [a-zA-Z_*?][a-zA-Z0-9_*?]* name_minus [a-zA-Z_*?][a-zA-Z0-9\-_*?]* -modifier_event [ukhpGH]+ +modifier_event [ukhpGHS]+ modifier_bp [rwx]{1,3} %%