[PATCH 1/4] perf record: Make per-cpu mmaps the default.
From: Adrian Hunter
Date: Mon Nov 18 2013 - 04:49:42 EST
This affects the -p, -t and -u options that
previously defaulted to per-thread mmaps.
A side-effect is that inheritance is
automatically enabled by default. A later
patch will disable it by default for the -t
option.
Consequently add an option to select
per-thread mmaps to support the old
behaviour.
Note that per-thread can be used with a
workload-only (i.e. none of -p, -t, -u,
-a or -C is selected) to get a per-thread
mmap with no inheritance.
Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Requested-by: Ingo Molnar <mingo@xxxxxxxxxx>
---
tools/perf/Documentation/perf-record.txt | 10 +++++-----
tools/perf/builtin-record.c | 5 +++--
tools/perf/tests/attr/test-record-no-inherit | 2 +-
tools/perf/util/evlist.c | 6 ++++--
tools/perf/util/evsel.c | 5 +++--
tools/perf/util/target.c | 11 ++++++++++-
tools/perf/util/target.h | 4 +++-
7 files changed, 29 insertions(+), 14 deletions(-)
diff --git a/tools/perf/Documentation/perf-record.txt b/tools/perf/Documentation/perf-record.txt
index 43b42c4..6ac867e 100644
--- a/tools/perf/Documentation/perf-record.txt
+++ b/tools/perf/Documentation/perf-record.txt
@@ -201,11 +201,11 @@ abort events and some memory events in precise mode on modern Intel CPUs.
--transaction::
Record transaction flags for transaction related events.
---force-per-cpu::
-Force the use of per-cpu mmaps. By default, when tasks are specified (i.e. -p,
--t or -u options) per-thread mmaps are created. This option overrides that and
-forces per-cpu mmaps. A side-effect of that is that inheritance is
-automatically enabled. Add the -i option also to disable inheritance.
+--per-thread::
+Use per-thread mmaps. By default per-cpu mmaps are created. This option
+overrides that and uses per-thread mmaps. A side-effect of that is that
+inheritance is automatically disabled. --per-thread is ignored with a warning
+if combined with -a or -C options.
SEE ALSO
--------
diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 7c8020a..f5b18b8 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -800,6 +800,7 @@ static struct perf_record record = {
.freq = 4000,
.target = {
.uses_mmap = true,
+ .default_per_cpu = true,
},
},
};
@@ -888,8 +889,8 @@ const struct option record_options[] = {
"sample by weight (on special events only)"),
OPT_BOOLEAN(0, "transaction", &record.opts.sample_transaction,
"sample transaction flags (special events only)"),
- OPT_BOOLEAN(0, "force-per-cpu", &record.opts.target.force_per_cpu,
- "force the use of per-cpu mmaps"),
+ OPT_BOOLEAN(0, "per-thread", &record.opts.target.per_thread,
+ "use per-thread mmaps"),
OPT_END()
};
diff --git a/tools/perf/tests/attr/test-record-no-inherit b/tools/perf/tests/attr/test-record-no-inherit
index 9079a25..44edcb2 100644
--- a/tools/perf/tests/attr/test-record-no-inherit
+++ b/tools/perf/tests/attr/test-record-no-inherit
@@ -3,5 +3,5 @@ command = record
args = -i kill >/dev/null 2>&1
[event:base-record]
-sample_type=259
+sample_type=263
inherit=0
diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c
index bbc746a..76fa764 100644
--- a/tools/perf/util/evlist.c
+++ b/tools/perf/util/evlist.c
@@ -819,8 +819,10 @@ int perf_evlist__create_maps(struct perf_evlist *evlist, struct target *target)
if (evlist->threads == NULL)
return -1;
- if (target->force_per_cpu)
- evlist->cpus = cpu_map__new(target->cpu_list);
+ if (target->default_per_cpu)
+ evlist->cpus = target->per_thread ?
+ cpu_map__dummy_new() :
+ cpu_map__new(target->cpu_list);
else if (target__has_task(target))
evlist->cpus = cpu_map__dummy_new();
else if (!target__has_cpu(target) && !target->uses_mmap)
diff --git a/tools/perf/util/evsel.c b/tools/perf/util/evsel.c
index 46dd4c2..77e38ff 100644
--- a/tools/perf/util/evsel.c
+++ b/tools/perf/util/evsel.c
@@ -572,6 +572,7 @@ void perf_evsel__config(struct perf_evsel *evsel,
struct perf_evsel *leader = evsel->leader;
struct perf_event_attr *attr = &evsel->attr;
int track = !evsel->idx; /* only the first counter needs these */
+ bool per_cpu = opts->target.default_per_cpu && !opts->target.per_thread;
attr->sample_id_all = perf_missing_features.sample_id_all ? 0 : 1;
attr->inherit = !opts->no_inherit;
@@ -645,7 +646,7 @@ void perf_evsel__config(struct perf_evsel *evsel,
}
}
- if (target__has_cpu(&opts->target) || opts->target.force_per_cpu)
+ if (target__has_cpu(&opts->target))
perf_evsel__set_sample_bit(evsel, CPU);
if (opts->period)
@@ -653,7 +654,7 @@ void perf_evsel__config(struct perf_evsel *evsel,
if (!perf_missing_features.sample_id_all &&
(opts->sample_time || !opts->no_inherit ||
- target__has_cpu(&opts->target) || opts->target.force_per_cpu))
+ target__has_cpu(&opts->target) || per_cpu))
perf_evsel__set_sample_bit(evsel, TIME);
if (opts->raw_samples) {
diff --git a/tools/perf/util/target.c b/tools/perf/util/target.c
index 3c778a0..e74c596 100644
--- a/tools/perf/util/target.c
+++ b/tools/perf/util/target.c
@@ -55,6 +55,13 @@ enum target_errno target__validate(struct target *target)
ret = TARGET_ERRNO__UID_OVERRIDE_SYSTEM;
}
+ /* THREAD and SYSTEM/CPU are mutually exclusive */
+ if (target->per_thread && (target->system_wide || target->cpu_list)) {
+ target->per_thread = false;
+ if (ret == TARGET_ERRNO__SUCCESS)
+ ret = TARGET_ERRNO__SYSTEM_OVERRIDE_THREAD;
+ }
+
return ret;
}
@@ -100,6 +107,7 @@ static const char *target__error_str[] = {
"UID switch overriding CPU",
"PID/TID switch overriding SYSTEM",
"UID switch overriding SYSTEM",
+ "SYSTEM/CPU switch overriding PER-THREAD",
"Invalid User: %s",
"Problems obtaining information for user %s",
};
@@ -131,7 +139,8 @@ int target__strerror(struct target *target, int errnum,
msg = target__error_str[idx];
switch (errnum) {
- case TARGET_ERRNO__PID_OVERRIDE_CPU ... TARGET_ERRNO__UID_OVERRIDE_SYSTEM:
+ case TARGET_ERRNO__PID_OVERRIDE_CPU ...
+ TARGET_ERRNO__SYSTEM_OVERRIDE_THREAD:
snprintf(buf, buflen, "%s", msg);
break;
diff --git a/tools/perf/util/target.h b/tools/perf/util/target.h
index 2d0c506..31dd2e9 100644
--- a/tools/perf/util/target.h
+++ b/tools/perf/util/target.h
@@ -12,7 +12,8 @@ struct target {
uid_t uid;
bool system_wide;
bool uses_mmap;
- bool force_per_cpu;
+ bool default_per_cpu;
+ bool per_thread;
};
enum target_errno {
@@ -33,6 +34,7 @@ enum target_errno {
TARGET_ERRNO__UID_OVERRIDE_CPU,
TARGET_ERRNO__PID_OVERRIDE_SYSTEM,
TARGET_ERRNO__UID_OVERRIDE_SYSTEM,
+ TARGET_ERRNO__SYSTEM_OVERRIDE_THREAD,
/* for target__parse_uid() */
TARGET_ERRNO__INVALID_UID,
--
1.7.11.7
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