diff options
| author | Ingo Molnar <mingo@elte.hu> | 2009-06-03 19:59:24 +0200 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2009-06-03 20:03:32 +0200 |
| commit | eed4dcd443da7a46131ef37c7a389b444905960e (patch) | |
| tree | f9dfab55e3f14c956ec1d4e3f85487d3258962ef /Documentation/perf_counter/builtin-report.c | |
| parent | 44db76c8553c328f4ae02481d77bb3a88ca17645 (diff) | |
| download | lwn-eed4dcd443da7a46131ef37c7a389b444905960e.tar.gz lwn-eed4dcd443da7a46131ef37c7a389b444905960e.zip | |
perf report: Add front-entry cache for lookups
Before:
Performance counter stats for './perf report -i perf.data.big':
12453988058 instructions
Performance counter stats for './perf report -i perf.data.big':
12379566017 instructions
0.60% reduction.
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'Documentation/perf_counter/builtin-report.c')
| -rw-r--r-- | Documentation/perf_counter/builtin-report.c | 15 |
1 files changed, 14 insertions, 1 deletions
diff --git a/Documentation/perf_counter/builtin-report.c b/Documentation/perf_counter/builtin-report.c index e837bb983dca..33b3b15fb014 100644 --- a/Documentation/perf_counter/builtin-report.c +++ b/Documentation/perf_counter/builtin-report.c @@ -229,6 +229,7 @@ static int thread__set_comm(struct thread *self, const char *comm) } static struct rb_root threads; +static struct thread *last_match; static struct thread *threads__findnew(pid_t pid) { @@ -236,12 +237,22 @@ static struct thread *threads__findnew(pid_t pid) struct rb_node *parent = NULL; struct thread *th; + /* + * Font-end cache - PID lookups come in blocks, + * so most of the time we dont have to look up + * the full rbtree: + */ + if (last_match && last_match->pid == pid) + return last_match; + while (*p != NULL) { parent = *p; th = rb_entry(parent, struct thread, rb_node); - if (th->pid == pid) + if (th->pid == pid) { + last_match = th; return th; + } if (pid < th->pid) p = &(*p)->rb_left; @@ -253,7 +264,9 @@ static struct thread *threads__findnew(pid_t pid) if (th != NULL) { rb_link_node(&th->rb_node, parent, p); rb_insert_color(&th->rb_node, &threads); + last_match = th; } + return th; } |