perf_counter tools: Set the minimum percent for callchains to be displayed
Callchains output may become a burden on a trace because even
rarely hit site are exposed. This can be too much information.
Let the user set a threshold as a minimum percent of hits using
the new pattern for the -c option:
-c mode,min_percent
Example:
$ perf report -s sym -c flat,4
8.25% [k] copy_user_generic_string
4.19%
copy_user_generic_string
generic_file_aio_read
do_sync_read
vfs_read
sys_pread64
system_call_fastpath
pread64
5.39% [k] search_by_key
4.63% 0x00000000009e0a
2.36% [k] memcpy_c
[...]
$ perf report -s sym -c graph,2
8.25% [k] copy_user_generic_string
|
|--4.31%-- generic_file_aio_read
| do_sync_read
| vfs_read
| |
| --4.19%-- sys_pread64
| system_call_fastpath
| pread64
|
--3.24%-- generic_file_buffered_write
__generic_file_aio_write_nolock
generic_file_aio_write
do_sync_write
reiserfs_file_write
vfs_write
|
--3.14%-- sys_pwrite64
system_call_fastpath
__pwrite64
5.39% [k] search_by_key
|
--2.23%-- reiserfs_update_sd_size
4.63% 0x00000000009e0a
2.36% [k] memcpy_c
[...]
You can also omit it and it will default to 0.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Anton Blanchard <anton@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
LKML-Reference: <1246558475-10624-1-git-send-email-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/tools/perf/util/callchain.c b/tools/perf/util/callchain.c
index a9873aa..c9900fe 100644
--- a/tools/perf/util/callchain.c
+++ b/tools/perf/util/callchain.c
@@ -57,18 +57,19 @@
* Once we get every callchains from the stream, we can now
* sort them by hit
*/
-void sort_chain_flat(struct rb_root *rb_root, struct callchain_node *node)
+void sort_chain_flat(struct rb_root *rb_root, struct callchain_node *node,
+ u64 min_hit)
{
struct callchain_node *child;
chain_for_each_child(child, node)
- sort_chain_flat(rb_root, child);
+ sort_chain_flat(rb_root, child, min_hit);
- if (node->hit)
+ if (node->hit && node->hit >= min_hit)
rb_insert_callchain(rb_root, node, FLAT);
}
-static void __sort_chain_graph(struct callchain_node *node)
+static void __sort_chain_graph(struct callchain_node *node, u64 min_hit)
{
struct callchain_node *child;
@@ -76,16 +77,18 @@
node->cumul_hit = node->hit;
chain_for_each_child(child, node) {
- __sort_chain_graph(child);
- rb_insert_callchain(&node->rb_root, child, GRAPH);
+ __sort_chain_graph(child, min_hit);
+ if (child->cumul_hit >= min_hit)
+ rb_insert_callchain(&node->rb_root, child, GRAPH);
node->cumul_hit += child->cumul_hit;
}
}
void
-sort_chain_graph(struct rb_root *rb_root, struct callchain_node *chain_root)
+sort_chain_graph(struct rb_root *rb_root, struct callchain_node *chain_root,
+ u64 min_hit)
{
- __sort_chain_graph(chain_root);
+ __sort_chain_graph(chain_root, min_hit);
rb_root->rb_node = chain_root->rb_root.rb_node;
}