From 9a92b479b2f088ee2d3194243f4c8e59b1b8c9c2 Mon Sep 17 00:00:00 2001 From: Frederic Weisbecker Date: Thu, 8 Oct 2009 16:37:12 +0200 Subject: [PATCH] perf tools: Improve thread comm resolution in perf sched When we get sched traces that involve a task that was already created before opening the event, we won't have the comm event for it. So if we can't find the comm event for a given thread, we look at the traces that may contain these informations. Before: ata/1:371 | 0.000 ms | 1 | avg: 3988.693 ms | max: 3988.693 ms | kondemand/1:421 | 0.096 ms | 3 | avg: 345.346 ms | max: 1035.989 ms | kondemand/0:420 | 0.025 ms | 3 | avg: 421.332 ms | max: 964.014 ms | :5124:5124 | 0.103 ms | 5 | avg: 74.082 ms | max: 277.194 ms | :6244:6244 | 0.691 ms | 9 | avg: 125.655 ms | max: 271.306 ms | firefox:5080 | 0.924 ms | 5 | avg: 53.833 ms | max: 257.828 ms | npviewer.bin:6225 | 21.871 ms | 53 | avg: 22.462 ms | max: 220.835 ms | :6245:6245 | 9.631 ms | 21 | avg: 41.864 ms | max: 213.349 ms | After: ata/1:371 | 0.000 ms | 1 | avg: 3988.693 ms | max: 3988.693 ms | kondemand/1:421 | 0.096 ms | 3 | avg: 345.346 ms | max: 1035.989 ms | kondemand/0:420 | 0.025 ms | 3 | avg: 421.332 ms | max: 964.014 ms | firefox:5124 | 0.103 ms | 5 | avg: 74.082 ms | max: 277.194 ms | npviewer.bin:6244 | 0.691 ms | 9 | avg: 125.655 ms | max: 271.306 ms | firefox:5080 | 0.924 ms | 5 | avg: 53.833 ms | max: 257.828 ms | npviewer.bin:6225 | 21.871 ms | 53 | avg: 22.462 ms | max: 220.835 ms | npviewer.bin:6245 | 9.631 ms | 21 | avg: 41.864 ms | max: 213.349 ms | Signed-off-by: Frederic Weisbecker Cc: Peter Zijlstra Cc: Arnaldo Carvalho de Melo Cc: Mike Galbraith Cc: Paul Mackerras LKML-Reference: <1255012632-7882-1-git-send-email-fweisbec@gmail.com> Signed-off-by: Ingo Molnar --- tools/perf/builtin-sched.c | 44 +++++++++++++++++++++++++++++++++----- tools/perf/util/thread.c | 32 +++++++++++++++++++++------ tools/perf/util/thread.h | 3 +++ 3 files changed, 67 insertions(+), 12 deletions(-) diff --git a/tools/perf/builtin-sched.c b/tools/perf/builtin-sched.c index e1df7055ab8..25b91e78433 100644 --- a/tools/perf/builtin-sched.c +++ b/tools/perf/builtin-sched.c @@ -1034,6 +1034,36 @@ add_sched_in_event(struct work_atoms *atoms, u64 timestamp) atoms->nb_atoms++; } +static struct thread * +threads__findnew_from_ctx(u32 pid, struct trace_switch_event *switch_event) +{ + struct thread *th; + + th = threads__findnew_nocomm(pid, &threads, &last_match); + if (th->comm) + return th; + + if (pid == switch_event->prev_pid) + thread__set_comm(th, switch_event->prev_comm); + else + thread__set_comm(th, switch_event->next_comm); + return th; +} + +static struct thread * +threads__findnew_from_wakeup(struct trace_wakeup_event *wakeup_event) +{ + struct thread *th; + + th = threads__findnew_nocomm(wakeup_event->pid, &threads, &last_match); + if (th->comm) + return th; + + thread__set_comm(th, wakeup_event->comm); + + return th; +} + static void latency_switch_event(struct trace_switch_event *switch_event, struct event *event __used, @@ -1059,8 +1089,10 @@ latency_switch_event(struct trace_switch_event *switch_event, die("hm, delta: %Ld < 0 ?\n", delta); - sched_out = threads__findnew(switch_event->prev_pid, &threads, &last_match); - sched_in = threads__findnew(switch_event->next_pid, &threads, &last_match); + sched_out = threads__findnew_from_ctx(switch_event->prev_pid, + switch_event); + sched_in = threads__findnew_from_ctx(switch_event->next_pid, + switch_event); out_events = thread_atoms_search(&atom_root, sched_out, &cmp_pid); if (!out_events) { @@ -1126,7 +1158,7 @@ latency_wakeup_event(struct trace_wakeup_event *wakeup_event, if (!wakeup_event->success) return; - wakee = threads__findnew(wakeup_event->pid, &threads, &last_match); + wakee = threads__findnew_from_wakeup(wakeup_event); atoms = thread_atoms_search(&atom_root, wakee, &cmp_pid); if (!atoms) { thread_atoms_insert(wakee); @@ -1386,8 +1418,10 @@ map_switch_event(struct trace_switch_event *switch_event, die("hm, delta: %Ld < 0 ?\n", delta); - sched_out = threads__findnew(switch_event->prev_pid, &threads, &last_match); - sched_in = threads__findnew(switch_event->next_pid, &threads, &last_match); + sched_out = threads__findnew_from_ctx(switch_event->prev_pid, + switch_event); + sched_in = threads__findnew_from_ctx(switch_event->next_pid, + switch_event); curr_thread[this_cpu] = sched_in; diff --git a/tools/perf/util/thread.c b/tools/perf/util/thread.c index 3b56aebb1f4..8bd5ca2d2f2 100644 --- a/tools/perf/util/thread.c +++ b/tools/perf/util/thread.c @@ -6,15 +6,17 @@ #include "util.h" #include "debug.h" -static struct thread *thread__new(pid_t pid) +static struct thread *thread__new(pid_t pid, int set_comm) { struct thread *self = calloc(1, sizeof(*self)); if (self != NULL) { self->pid = pid; - self->comm = malloc(32); - if (self->comm) - snprintf(self->comm, 32, ":%d", self->pid); + if (set_comm) { + self->comm = malloc(32); + if (self->comm) + snprintf(self->comm, 32, ":%d", self->pid); + } self->maps = RB_ROOT; INIT_LIST_HEAD(&self->removed_maps); } @@ -50,8 +52,10 @@ static size_t thread__fprintf(struct thread *self, FILE *fp) return ret; } -struct thread * -threads__findnew(pid_t pid, struct rb_root *threads, struct thread **last_match) +static struct thread * +__threads__findnew(pid_t pid, struct rb_root *threads, + struct thread **last_match, + int set_comm) { struct rb_node **p = &threads->rb_node; struct rb_node *parent = NULL; @@ -80,7 +84,8 @@ threads__findnew(pid_t pid, struct rb_root *threads, struct thread **last_match) p = &(*p)->rb_right; } - th = thread__new(pid); + th = thread__new(pid, set_comm); + if (th != NULL) { rb_link_node(&th->rb_node, parent, p); rb_insert_color(&th->rb_node, threads); @@ -90,6 +95,19 @@ threads__findnew(pid_t pid, struct rb_root *threads, struct thread **last_match) return th; } +struct thread * +threads__findnew(pid_t pid, struct rb_root *threads, struct thread **last_match) +{ + return __threads__findnew(pid, threads, last_match, 1); +} + +struct thread * +threads__findnew_nocomm(pid_t pid, struct rb_root *threads, + struct thread **last_match) +{ + return __threads__findnew(pid, threads, last_match, 0); +} + struct thread * register_idle_thread(struct rb_root *threads, struct thread **last_match) { diff --git a/tools/perf/util/thread.h b/tools/perf/util/thread.h index 845d9b62f96..75bc843950c 100644 --- a/tools/perf/util/thread.h +++ b/tools/perf/util/thread.h @@ -18,6 +18,9 @@ int thread__set_comm(struct thread *self, const char *comm); struct thread * threads__findnew(pid_t pid, struct rb_root *threads, struct thread **last_match); struct thread * +threads__findnew_nocomm(pid_t pid, struct rb_root *threads, + struct thread **last_match); +struct thread * register_idle_thread(struct rb_root *threads, struct thread **last_match); void thread__insert_map(struct thread *self, struct map *map); int thread__fork(struct thread *self, struct thread *parent); -- 2.41.0