From aece948f5ddd70d70df2f35855c706ef9a4f62e2 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Sun, 15 May 2011 09:39:00 -0300 Subject: [PATCH] perf evlist: Fix per thread mmap setup The PERF_EVENT_IOC_SET_OUTPUT ioctl was returning -EINVAL when using --pid when monitoring multithreaded apps, as we can only share a ring buffer for events on the same thread if not doing per cpu. Fix it by using per thread ring buffers. Tested with: [root@felicio ~]# tuna -t 26131 -CP | nl 1 thread ctxt_switches 2 pid SCHED_ rtpri affinity voluntary nonvoluntary cmd 3 26131 OTHER 0 0,1 10814276 2397830 chromium-browse 4 642 OTHER 0 0,1 14688 0 chromium-browse 5 26148 OTHER 0 0,1 713602 115479 chromium-browse 6 26149 OTHER 0 0,1 801958 2262 chromium-browse 7 26150 OTHER 0 0,1 1271128 248 chromium-browse 8 26151 OTHER 0 0,1 3 0 chromium-browse 9 27049 OTHER 0 0,1 36796 9 chromium-browse 10 618 OTHER 0 0,1 14711 0 chromium-browse 11 661 OTHER 0 0,1 14593 0 chromium-browse 12 29048 OTHER 0 0,1 28125 0 chromium-browse 13 26143 OTHER 0 0,1 2202789 781 chromium-browse [root@felicio ~]# So 11 threads under pid 26131, then: [root@felicio ~]# perf record -F 50000 --pid 26131 [root@felicio ~]# grep perf_event /proc/`pidof perf`/maps | nl 1 7fa4a2538000-7fa4a25b9000 rwxs 00000000 00:09 4064 anon_inode:[perf_event] 2 7fa4a25b9000-7fa4a263a000 rwxs 00000000 00:09 4064 anon_inode:[perf_event] 3 7fa4a263a000-7fa4a26bb000 rwxs 00000000 00:09 4064 anon_inode:[perf_event] 4 7fa4a26bb000-7fa4a273c000 rwxs 00000000 00:09 4064 anon_inode:[perf_event] 5 7fa4a273c000-7fa4a27bd000 rwxs 00000000 00:09 4064 anon_inode:[perf_event] 6 7fa4a27bd000-7fa4a283e000 rwxs 00000000 00:09 4064 anon_inode:[perf_event] 7 7fa4a283e000-7fa4a28bf000 rwxs 00000000 00:09 4064 anon_inode:[perf_event] 8 7fa4a28bf000-7fa4a2940000 rwxs 00000000 00:09 4064 anon_inode:[perf_event] 9 7fa4a2940000-7fa4a29c1000 rwxs 00000000 00:09 4064 anon_inode:[perf_event] 10 7fa4a29c1000-7fa4a2a42000 rwxs 00000000 00:09 4064 anon_inode:[perf_event] 11 7fa4a2a42000-7fa4a2ac3000 rwxs 00000000 00:09 4064 anon_inode:[perf_event] [root@felicio ~]# 11 mmaps, one per thread since we didn't specify any CPU list, so we need one mmap per thread and: [root@felicio ~]# perf record -F 50000 --pid 26131 ^M ^C[ perf record: Woken up 79 times to write data ] [ perf record: Captured and wrote 20.614 MB perf.data (~900639 samples) ] [root@felicio ~]# perf report -D | grep PERF_RECORD_SAMPLE | cut -d/ -f2 | cut -d: -f1 | sort -n | uniq -c | sort -nr | nl 1 371310 26131 2 96516 26148 3 95694 26149 4 95203 26150 5 7291 26143 6 87 27049 7 76 661 8 60 29048 9 47 618 10 43 642 [root@felicio ~]# Ok, one of the threads, 26151 was quiescent, so no samples there, but all the others are there. Then, if I specify one CPU: [root@felicio ~]# perf record -F 50000 --pid 26131 --cpu 1 ^C[ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.680 MB perf.data (~29730 samples) ] [root@felicio ~]# perf report -D | grep PERF_RECORD_SAMPLE | cut -d/ -f2 | cut -d: -f1 | sort -n | uniq -c | sort -nr | nl 1 8444 26131 2 2584 26149 3 2518 26148 4 2324 26150 5 123 26143 6 9 661 7 9 29048 [root@felicio ~]# This machine has two cores, so fewer threads appeared on the radar, and: [root@felicio ~]# grep perf_event /proc/`pidof perf`/maps | nl 1 7f484b922000-7f484b9a3000 rwxs 00000000 00:09 4064 anon_inode:[perf_event] [root@felicio ~]# Just one mmap, as now we can use just one per-cpu buffer instead of the per-thread needed in the previous case. For global profiling: [root@felicio ~]# perf record -F 50000 -a ^C[ perf record: Woken up 26 times to write data ] [ perf record: Captured and wrote 7.128 MB perf.data (~311412 samples) ] [root@felicio ~]# grep perf_event /proc/`pidof perf`/maps | nl 1 7fb49b435000-7fb49b4b6000 rwxs 00000000 00:09 4064 anon_inode:[perf_event] 2 7fb49b4b6000-7fb49b537000 rwxs 00000000 00:09 4064 anon_inode:[perf_event] [root@felicio ~]# It uses per-cpu buffers. For just one thread: [root@felicio ~]# perf record -F 50000 --tid 26148 ^C[ perf record: Woken up 2 times to write data ] [ perf record: Captured and wrote 0.330 MB perf.data (~14426 samples) ] [root@felicio ~]# perf report -D | grep PERF_RECORD_SAMPLE | cut -d/ -f2 | cut -d: -f1 | sort -n | uniq -c | sort -nr | nl 1 9969 26148 [root@felicio ~]# [root@felicio ~]# grep perf_event /proc/`pidof perf`/maps | nl 1 7f286a51b000-7f286a59c000 rwxs 00000000 00:09 4064 anon_inode:[perf_event] [root@felicio ~]# Tested-by: David Ahern Tested-by: Lin Ming Cc: Frederic Weisbecker Cc: Ingo Molnar Cc: Mike Galbraith Cc: Paul Mackerras Cc: Peter Zijlstra Cc: Stephane Eranian Cc: Tom Zanussi Link: http://lkml.kernel.org/r/20110426204401.GB1746@ghostprotocols.net Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-record.c | 2 +- tools/perf/builtin-test.c | 2 +- tools/perf/builtin-top.c | 8 +- tools/perf/util/evlist.c | 151 +++++++++++++++++++++++++----------- tools/perf/util/evlist.h | 3 +- tools/perf/util/python.c | 2 +- 6 files changed, 115 insertions(+), 53 deletions(-) diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index 416538248a4b..0974f957b8fa 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -427,7 +427,7 @@ static void mmap_read_all(void) { int i; - for (i = 0; i < evsel_list->cpus->nr; i++) { + for (i = 0; i < evsel_list->nr_mmaps; i++) { if (evsel_list->mmap[i].base) mmap_read(&evsel_list->mmap[i]); } diff --git a/tools/perf/builtin-test.c b/tools/perf/builtin-test.c index 11e3c8458362..2f9a337b182f 100644 --- a/tools/perf/builtin-test.c +++ b/tools/perf/builtin-test.c @@ -549,7 +549,7 @@ static int test__basic_mmap(void) ++foo; } - while ((event = perf_evlist__read_on_cpu(evlist, 0)) != NULL) { + while ((event = perf_evlist__mmap_read(evlist, 0)) != NULL) { struct perf_sample sample; if (event->header.type != PERF_RECORD_SAMPLE) { diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c index 7e3d6e310bf8..ebfc7cf5f63b 100644 --- a/tools/perf/builtin-top.c +++ b/tools/perf/builtin-top.c @@ -801,12 +801,12 @@ static void perf_event__process_sample(const union perf_event *event, } } -static void perf_session__mmap_read_cpu(struct perf_session *self, int cpu) +static void perf_session__mmap_read_idx(struct perf_session *self, int idx) { struct perf_sample sample; union perf_event *event; - while ((event = perf_evlist__read_on_cpu(top.evlist, cpu)) != NULL) { + while ((event = perf_evlist__mmap_read(top.evlist, idx)) != NULL) { perf_session__parse_sample(self, event, &sample); if (event->header.type == PERF_RECORD_SAMPLE) @@ -820,8 +820,8 @@ static void perf_session__mmap_read(struct perf_session *self) { int i; - for (i = 0; i < top.evlist->cpus->nr; i++) - perf_session__mmap_read_cpu(self, i); + for (i = 0; i < top.evlist->nr_mmaps; i++) + perf_session__mmap_read_idx(self, i); } static void start_counters(struct perf_evlist *evlist) diff --git a/tools/perf/util/evlist.c b/tools/perf/util/evlist.c index 1884a7c7eb8f..23eb22b05d27 100644 --- a/tools/perf/util/evlist.c +++ b/tools/perf/util/evlist.c @@ -166,11 +166,11 @@ struct perf_evsel *perf_evlist__id2evsel(struct perf_evlist *evlist, u64 id) return NULL; } -union perf_event *perf_evlist__read_on_cpu(struct perf_evlist *evlist, int cpu) +union perf_event *perf_evlist__mmap_read(struct perf_evlist *evlist, int idx) { /* XXX Move this to perf.c, making it generally available */ unsigned int page_size = sysconf(_SC_PAGE_SIZE); - struct perf_mmap *md = &evlist->mmap[cpu]; + struct perf_mmap *md = &evlist->mmap[idx]; unsigned int head = perf_mmap__read_head(md); unsigned int old = md->prev; unsigned char *data = md->base + page_size; @@ -235,31 +235,37 @@ union perf_event *perf_evlist__read_on_cpu(struct perf_evlist *evlist, int cpu) void perf_evlist__munmap(struct perf_evlist *evlist) { - int cpu; + int i; - for (cpu = 0; cpu < evlist->cpus->nr; cpu++) { - if (evlist->mmap[cpu].base != NULL) { - munmap(evlist->mmap[cpu].base, evlist->mmap_len); - evlist->mmap[cpu].base = NULL; + for (i = 0; i < evlist->nr_mmaps; i++) { + if (evlist->mmap[i].base != NULL) { + munmap(evlist->mmap[i].base, evlist->mmap_len); + evlist->mmap[i].base = NULL; } } + + free(evlist->mmap); + evlist->mmap = NULL; } int perf_evlist__alloc_mmap(struct perf_evlist *evlist) { - evlist->mmap = zalloc(evlist->cpus->nr * sizeof(struct perf_mmap)); + evlist->nr_mmaps = evlist->cpus->nr; + if (evlist->cpus->map[0] == -1) + evlist->nr_mmaps = evlist->threads->nr; + evlist->mmap = zalloc(evlist->nr_mmaps * sizeof(struct perf_mmap)); return evlist->mmap != NULL ? 0 : -ENOMEM; } static int __perf_evlist__mmap(struct perf_evlist *evlist, struct perf_evsel *evsel, - int cpu, int prot, int mask, int fd) + int idx, int prot, int mask, int fd) { - evlist->mmap[cpu].prev = 0; - evlist->mmap[cpu].mask = mask; - evlist->mmap[cpu].base = mmap(NULL, evlist->mmap_len, prot, + evlist->mmap[idx].prev = 0; + evlist->mmap[idx].mask = mask; + evlist->mmap[idx].base = mmap(NULL, evlist->mmap_len, prot, MAP_SHARED, fd, 0); - if (evlist->mmap[cpu].base == MAP_FAILED) { - if (evlist->cpus->map[cpu] == -1 && evsel->attr.inherit) + if (evlist->mmap[idx].base == MAP_FAILED) { + if (evlist->cpus->map[idx] == -1 && evsel->attr.inherit) ui__warning("Inherit is not allowed on per-task " "events using mmap.\n"); return -1; @@ -269,6 +275,86 @@ static int __perf_evlist__mmap(struct perf_evlist *evlist, struct perf_evsel *ev return 0; } +static int perf_evlist__mmap_per_cpu(struct perf_evlist *evlist, int prot, int mask) +{ + struct perf_evsel *evsel; + int cpu, thread; + + for (cpu = 0; cpu < evlist->cpus->nr; cpu++) { + int output = -1; + + for (thread = 0; thread < evlist->threads->nr; thread++) { + list_for_each_entry(evsel, &evlist->entries, node) { + int fd = FD(evsel, cpu, thread); + + if (output == -1) { + output = fd; + if (__perf_evlist__mmap(evlist, evsel, cpu, + prot, mask, output) < 0) + goto out_unmap; + } else { + if (ioctl(fd, PERF_EVENT_IOC_SET_OUTPUT, output) != 0) + goto out_unmap; + } + + if ((evsel->attr.read_format & PERF_FORMAT_ID) && + perf_evlist__id_add_fd(evlist, evsel, cpu, thread, fd) < 0) + goto out_unmap; + } + } + } + + return 0; + +out_unmap: + for (cpu = 0; cpu < evlist->cpus->nr; cpu++) { + if (evlist->mmap[cpu].base != NULL) { + munmap(evlist->mmap[cpu].base, evlist->mmap_len); + evlist->mmap[cpu].base = NULL; + } + } + return -1; +} + +static int perf_evlist__mmap_per_thread(struct perf_evlist *evlist, int prot, int mask) +{ + struct perf_evsel *evsel; + int thread; + + for (thread = 0; thread < evlist->threads->nr; thread++) { + int output = -1; + + list_for_each_entry(evsel, &evlist->entries, node) { + int fd = FD(evsel, 0, thread); + + if (output == -1) { + output = fd; + if (__perf_evlist__mmap(evlist, evsel, thread, + prot, mask, output) < 0) + goto out_unmap; + } else { + if (ioctl(fd, PERF_EVENT_IOC_SET_OUTPUT, output) != 0) + goto out_unmap; + } + + if ((evsel->attr.read_format & PERF_FORMAT_ID) && + perf_evlist__id_add_fd(evlist, evsel, 0, thread, fd) < 0) + goto out_unmap; + } + } + + return 0; + +out_unmap: + for (thread = 0; thread < evlist->threads->nr; thread++) { + if (evlist->mmap[thread].base != NULL) { + munmap(evlist->mmap[thread].base, evlist->mmap_len); + evlist->mmap[thread].base = NULL; + } + } + return -1; +} + /** perf_evlist__mmap - Create per cpu maps to receive events * * @evlist - list of events @@ -287,11 +373,11 @@ static int __perf_evlist__mmap(struct perf_evlist *evlist, struct perf_evsel *ev int perf_evlist__mmap(struct perf_evlist *evlist, int pages, bool overwrite) { unsigned int page_size = sysconf(_SC_PAGE_SIZE); - int mask = pages * page_size - 1, cpu; - struct perf_evsel *first_evsel, *evsel; + int mask = pages * page_size - 1; + struct perf_evsel *evsel; const struct cpu_map *cpus = evlist->cpus; const struct thread_map *threads = evlist->threads; - int thread, prot = PROT_READ | (overwrite ? 0 : PROT_WRITE); + int prot = PROT_READ | (overwrite ? 0 : PROT_WRITE); if (evlist->mmap == NULL && perf_evlist__alloc_mmap(evlist) < 0) return -ENOMEM; @@ -301,43 +387,18 @@ int perf_evlist__mmap(struct perf_evlist *evlist, int pages, bool overwrite) evlist->overwrite = overwrite; evlist->mmap_len = (pages + 1) * page_size; - first_evsel = list_entry(evlist->entries.next, struct perf_evsel, node); list_for_each_entry(evsel, &evlist->entries, node) { if ((evsel->attr.read_format & PERF_FORMAT_ID) && evsel->sample_id == NULL && perf_evsel__alloc_id(evsel, cpus->nr, threads->nr) < 0) return -ENOMEM; - - for (cpu = 0; cpu < cpus->nr; cpu++) { - for (thread = 0; thread < threads->nr; thread++) { - int fd = FD(evsel, cpu, thread); - - if (evsel->idx || thread) { - if (ioctl(fd, PERF_EVENT_IOC_SET_OUTPUT, - FD(first_evsel, cpu, 0)) != 0) - goto out_unmap; - } else if (__perf_evlist__mmap(evlist, evsel, cpu, - prot, mask, fd) < 0) - goto out_unmap; - - if ((evsel->attr.read_format & PERF_FORMAT_ID) && - perf_evlist__id_add_fd(evlist, evsel, cpu, thread, fd) < 0) - goto out_unmap; - } - } } - return 0; + if (evlist->cpus->map[0] == -1) + return perf_evlist__mmap_per_thread(evlist, prot, mask); -out_unmap: - for (cpu = 0; cpu < cpus->nr; cpu++) { - if (evlist->mmap[cpu].base != NULL) { - munmap(evlist->mmap[cpu].base, evlist->mmap_len); - evlist->mmap[cpu].base = NULL; - } - } - return -1; + return perf_evlist__mmap_per_cpu(evlist, prot, mask); } int perf_evlist__create_maps(struct perf_evlist *evlist, pid_t target_pid, diff --git a/tools/perf/util/evlist.h b/tools/perf/util/evlist.h index 8b1cb7a4c5f1..7109d7add14e 100644 --- a/tools/perf/util/evlist.h +++ b/tools/perf/util/evlist.h @@ -17,6 +17,7 @@ struct perf_evlist { struct hlist_head heads[PERF_EVLIST__HLIST_SIZE]; int nr_entries; int nr_fds; + int nr_mmaps; int mmap_len; bool overwrite; union perf_event event_copy; @@ -46,7 +47,7 @@ void perf_evlist__add_pollfd(struct perf_evlist *evlist, int fd); struct perf_evsel *perf_evlist__id2evsel(struct perf_evlist *evlist, u64 id); -union perf_event *perf_evlist__read_on_cpu(struct perf_evlist *self, int cpu); +union perf_event *perf_evlist__mmap_read(struct perf_evlist *self, int idx); int perf_evlist__alloc_mmap(struct perf_evlist *evlist); int perf_evlist__mmap(struct perf_evlist *evlist, int pages, bool overwrite); diff --git a/tools/perf/util/python.c b/tools/perf/util/python.c index f5e38451fdc5..99c722672f84 100644 --- a/tools/perf/util/python.c +++ b/tools/perf/util/python.c @@ -680,7 +680,7 @@ static PyObject *pyrf_evlist__read_on_cpu(struct pyrf_evlist *pevlist, &cpu, &sample_id_all)) return NULL; - event = perf_evlist__read_on_cpu(evlist, cpu); + event = perf_evlist__mmap_read(evlist, cpu); if (event != NULL) { struct perf_evsel *first; PyObject *pyevent = pyrf_event__new(event); -- 2.20.1