diff options
Diffstat (limited to 'tools/lib/perf/Documentation')
| -rw-r--r-- | tools/lib/perf/Documentation/examples/counting.c | 83 | ||||
| -rw-r--r-- | tools/lib/perf/Documentation/libperf-counting.txt | 14 | ||||
| -rw-r--r-- | tools/lib/perf/Documentation/libperf-sampling.txt | 13 | ||||
| -rw-r--r-- | tools/lib/perf/Documentation/libperf.txt | 23 |
4 files changed, 112 insertions, 21 deletions
diff --git a/tools/lib/perf/Documentation/examples/counting.c b/tools/lib/perf/Documentation/examples/counting.c new file mode 100644 index 000000000000..6085693571ef --- /dev/null +++ b/tools/lib/perf/Documentation/examples/counting.c @@ -0,0 +1,83 @@ +#include <linux/perf_event.h> +#include <perf/evlist.h> +#include <perf/evsel.h> +#include <perf/cpumap.h> +#include <perf/threadmap.h> +#include <perf/mmap.h> +#include <perf/core.h> +#include <perf/event.h> +#include <stdio.h> +#include <unistd.h> + +static int libperf_print(enum libperf_print_level level, + const char *fmt, va_list ap) +{ + return vfprintf(stderr, fmt, ap); +} + +int main(int argc, char **argv) +{ + int count = 100000, err = 0; + struct perf_evlist *evlist; + struct perf_evsel *evsel; + struct perf_thread_map *threads; + struct perf_counts_values counts; + + struct perf_event_attr attr1 = { + .type = PERF_TYPE_SOFTWARE, + .config = PERF_COUNT_SW_CPU_CLOCK, + .read_format = PERF_FORMAT_TOTAL_TIME_ENABLED|PERF_FORMAT_TOTAL_TIME_RUNNING, + .disabled = 1, + }; + struct perf_event_attr attr2 = { + .type = PERF_TYPE_SOFTWARE, + .config = PERF_COUNT_SW_TASK_CLOCK, + .read_format = PERF_FORMAT_TOTAL_TIME_ENABLED|PERF_FORMAT_TOTAL_TIME_RUNNING, + .disabled = 1, + }; + + libperf_init(libperf_print); + threads = perf_thread_map__new_dummy(); + if (!threads) { + fprintf(stderr, "failed to create threads\n"); + return -1; + } + perf_thread_map__set_pid(threads, 0, 0); + evlist = perf_evlist__new(); + if (!evlist) { + fprintf(stderr, "failed to create evlist\n"); + goto out_threads; + } + evsel = perf_evsel__new(&attr1); + if (!evsel) { + fprintf(stderr, "failed to create evsel1\n"); + goto out_evlist; + } + perf_evlist__add(evlist, evsel); + evsel = perf_evsel__new(&attr2); + if (!evsel) { + fprintf(stderr, "failed to create evsel2\n"); + goto out_evlist; + } + perf_evlist__add(evlist, evsel); + perf_evlist__set_maps(evlist, NULL, threads); + err = perf_evlist__open(evlist); + if (err) { + fprintf(stderr, "failed to open evsel\n"); + goto out_evlist; + } + perf_evlist__enable(evlist); + while (count--); + perf_evlist__disable(evlist); + perf_evlist__for_each_evsel(evlist, evsel) { + perf_evsel__read(evsel, 0, 0, &counts); + fprintf(stdout, "count %llu, enabled %llu, run %llu\n", + counts.val, counts.ena, counts.run); + } + perf_evlist__close(evlist); +out_evlist: + perf_evlist__delete(evlist); +out_threads: + perf_thread_map__put(threads); + return err; +} diff --git a/tools/lib/perf/Documentation/libperf-counting.txt b/tools/lib/perf/Documentation/libperf-counting.txt index cae9757f49c1..8b75efcd67ce 100644 --- a/tools/lib/perf/Documentation/libperf-counting.txt +++ b/tools/lib/perf/Documentation/libperf-counting.txt @@ -7,13 +7,13 @@ libperf-counting - counting interface DESCRIPTION ----------- -The counting interface provides API to meassure and get count for specific perf events. +The counting interface provides API to measure and get count for specific perf events. The following test tries to explain count on `counting.c` example. It is by no means complete guide to counting, but shows libperf basic API for counting. -The `counting.c` comes with libbperf package and can be compiled and run like: +The `counting.c` comes with libperf package and can be compiled and run like: [source,bash] -- @@ -26,7 +26,8 @@ count 176242, enabled 176242, run 176242 It requires root access, because of the `PERF_COUNT_SW_CPU_CLOCK` event, which is available only for root. -The `counting.c` example monitors two events on the current process and displays their count, in a nutshel it: +The `counting.c` example monitors two events on the current process and displays +their count, in a nutshell it: * creates events * adds them to the event list @@ -152,7 +153,7 @@ Configure event list with the thread map and open events: -- Both events are created as disabled (note the `disabled = 1` assignment above), -so we need to enable the whole list explicitely (both events). +so we need to enable the whole list explicitly (both events). From this moment events are counting and we can do our workload. @@ -167,7 +168,8 @@ When we are done we disable the events list. 79 perf_evlist__disable(evlist); -- -Now we need to get the counts from events, following code iterates throught the events list and read counts: +Now we need to get the counts from events, following code iterates through the +events list and read counts: [source,c] -- @@ -178,7 +180,7 @@ Now we need to get the counts from events, following code iterates throught the 85 } -- -And finaly cleanup. +And finally cleanup. We close the whole events list (both events) and remove it together with the threads map: diff --git a/tools/lib/perf/Documentation/libperf-sampling.txt b/tools/lib/perf/Documentation/libperf-sampling.txt index d71a7b4fcf5f..d6ca24f6ef78 100644 --- a/tools/lib/perf/Documentation/libperf-sampling.txt +++ b/tools/lib/perf/Documentation/libperf-sampling.txt @@ -8,13 +8,13 @@ libperf-sampling - sampling interface DESCRIPTION ----------- -The sampling interface provides API to meassure and get count for specific perf events. +The sampling interface provides API to measure and get count for specific perf events. The following test tries to explain count on `sampling.c` example. It is by no means complete guide to sampling, but shows libperf basic API for sampling. -The `sampling.c` comes with libbperf package and can be compiled and run like: +The `sampling.c` comes with libperf package and can be compiled and run like: [source,bash] -- @@ -33,7 +33,8 @@ cpu 0, pid 4465, tid 4470, ip 7f84fe0ebebf, period 176 It requires root access, because it uses hardware cycles event. -The `sampling.c` example profiles/samples all CPUs with hardware cycles, in a nutshel it: +The `sampling.c` example profiles/samples all CPUs with hardware cycles, in a +nutshell it: - creates events - adds them to the event list @@ -90,7 +91,7 @@ Once the setup is complete we start by defining cycles event using the `struct p 36 }; -- -Next step is to prepare cpus map. +Next step is to prepare CPUs map. In this case we will monitor all the available CPUs: @@ -152,7 +153,7 @@ Once the events list is open, we can create memory maps AKA perf ring buffers: -- The event is created as disabled (note the `disabled = 1` assignment above), -so we need to enable the events list explicitely. +so we need to enable the events list explicitly. From this moment the cycles event is sampling. @@ -212,7 +213,7 @@ Each sample needs to get parsed: 106 cpu, pid, tid, ip, period); -- -And finaly cleanup. +And finally cleanup. We close the whole events list (both events) and remove it together with the threads map: diff --git a/tools/lib/perf/Documentation/libperf.txt b/tools/lib/perf/Documentation/libperf.txt index 5a6bb512789d..a8f1a237931b 100644 --- a/tools/lib/perf/Documentation/libperf.txt +++ b/tools/lib/perf/Documentation/libperf.txt @@ -29,7 +29,7 @@ SYNOPSIS void libperf_init(libperf_print_fn_t fn); -- -*API to handle cpu maps:* +*API to handle CPU maps:* [source,c] -- @@ -48,6 +48,7 @@ SYNOPSIS int perf_cpu_map__nr(const struct perf_cpu_map *cpus); bool perf_cpu_map__empty(const struct perf_cpu_map *map); int perf_cpu_map__max(struct perf_cpu_map *map); + bool perf_cpu_map__has(const struct perf_cpu_map *map, int cpu); #define perf_cpu_map__for_each_cpu(cpu, idx, cpus) -- @@ -61,11 +62,12 @@ SYNOPSIS struct perf_thread_map; struct perf_thread_map *perf_thread_map__new_dummy(void); + struct perf_thread_map *perf_thread_map__new_array(int nr_threads, pid_t *array); - void perf_thread_map__set_pid(struct perf_thread_map *map, int thread, pid_t pid); - char *perf_thread_map__comm(struct perf_thread_map *map, int thread); + void perf_thread_map__set_pid(struct perf_thread_map *map, int idx, pid_t pid); + char *perf_thread_map__comm(struct perf_thread_map *map, int idx); int perf_thread_map__nr(struct perf_thread_map *threads); - pid_t perf_thread_map__pid(struct perf_thread_map *map, int thread); + pid_t perf_thread_map__pid(struct perf_thread_map *map, int idx); struct perf_thread_map *perf_thread_map__get(struct perf_thread_map *map); void perf_thread_map__put(struct perf_thread_map *map); @@ -135,13 +137,16 @@ SYNOPSIS int perf_evsel__open(struct perf_evsel *evsel, struct perf_cpu_map *cpus, struct perf_thread_map *threads); void perf_evsel__close(struct perf_evsel *evsel); - void perf_evsel__close_cpu(struct perf_evsel *evsel, int cpu); - int perf_evsel__read(struct perf_evsel *evsel, int cpu, int thread, + void perf_evsel__close_cpu(struct perf_evsel *evsel, int cpu_map_idx); + int perf_evsel__mmap(struct perf_evsel *evsel, int pages); + void perf_evsel__munmap(struct perf_evsel *evsel); + void *perf_evsel__mmap_base(struct perf_evsel *evsel, int cpu_map_idx, int thread); + int perf_evsel__read(struct perf_evsel *evsel, int cpu_map_idx, int thread, struct perf_counts_values *count); int perf_evsel__enable(struct perf_evsel *evsel); - int perf_evsel__enable_cpu(struct perf_evsel *evsel, int cpu); + int perf_evsel__enable_cpu(struct perf_evsel *evsel, int cpu_map_idx); int perf_evsel__disable(struct perf_evsel *evsel); - int perf_evsel__disable_cpu(struct perf_evsel *evsel, int cpu); + int perf_evsel__disable_cpu(struct perf_evsel *evsel, int cpu_map_idx); struct perf_cpu_map *perf_evsel__cpus(struct perf_evsel *evsel); struct perf_thread_map *perf_evsel__threads(struct perf_evsel *evsel); struct perf_event_attr *perf_evsel__attr(struct perf_evsel *evsel); @@ -217,7 +222,7 @@ Following objects are key to the libperf interface: [horizontal] -struct perf_cpu_map:: Provides a cpu list abstraction. +struct perf_cpu_map:: Provides a CPU list abstraction. struct perf_thread_map:: Provides a thread list abstraction. |