[PATCH RFC 09/10] perf top: add option to set the number of thread for event synthesize

From: kan . liang
Date: Thu Sep 07 2017 - 13:57:56 EST


From: Kan Liang <kan.liang@xxxxxxxxx>

Using UINT_MAX to indicate the default thread#, which is the max number
of online CPU.

Signed-off-by: Kan Liang <kan.liang@xxxxxxxxx>
---
tools/perf/builtin-top.c | 5 ++++-
tools/perf/util/event.c | 5 ++++-
tools/perf/util/top.h | 1 +
3 files changed, 9 insertions(+), 2 deletions(-)

diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index 4b8fdc1..5f59aa7 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -961,7 +961,7 @@ static int __cmd_top(struct perf_top *top)
machine__synthesize_threads(&top->session->machines.host, &opts->target,
top->evlist->threads, false,
opts->proc_map_timeout,
- (unsigned int)sysconf(_SC_NPROCESSORS_ONLN));
+ top->nr_threads_synthesize);

if (perf_hpp_list.socket) {
ret = perf_env__read_cpu_topology_map(&perf_env);
@@ -1114,6 +1114,7 @@ int cmd_top(int argc, const char **argv)
},
.max_stack = sysctl_perf_event_max_stack,
.sym_pcnt_filter = 5,
+ .nr_threads_synthesize = UINT_MAX,
};
struct record_opts *opts = &top.record_opts;
struct target *target = &opts->target;
@@ -1223,6 +1224,8 @@ int cmd_top(int argc, const char **argv)
OPT_BOOLEAN(0, "hierarchy", &symbol_conf.report_hierarchy,
"Show entries in a hierarchy"),
OPT_BOOLEAN(0, "force", &symbol_conf.force, "don't complain, do it"),
+ OPT_UINTEGER(0, "num-thread-synthesize", &top.nr_threads_synthesize,
+ "number of thread to run event synthesize"),
OPT_END()
};
const char * const top_usage[] = {
diff --git a/tools/perf/util/event.c b/tools/perf/util/event.c
index 4f565ff..2104603 100644
--- a/tools/perf/util/event.c
+++ b/tools/perf/util/event.c
@@ -777,7 +777,10 @@ int perf_event__synthesize_threads(struct perf_tool *tool,
if (n < 0)
return err;

- thread_nr = nr_threads_synthesize;
+ if (nr_threads_synthesize == UINT_MAX)
+ thread_nr = sysconf(_SC_NPROCESSORS_ONLN);
+ else
+ thread_nr = nr_threads_synthesize;
if (thread_nr <= 0)
thread_nr = 1;
if (thread_nr > n)
diff --git a/tools/perf/util/top.h b/tools/perf/util/top.h
index 9bdfb78..f4296e1 100644
--- a/tools/perf/util/top.h
+++ b/tools/perf/util/top.h
@@ -37,6 +37,7 @@ struct perf_top {
int sym_pcnt_filter;
const char *sym_filter;
float min_percent;
+ unsigned int nr_threads_synthesize;
};

#define CONSOLE_CLEAR ""
--
2.5.5