[tip:perfcounters/urgent] perf_counter tools: Set the minimum percent for callchains to be displayed

From: tip-bot for Frederic Weisbecker
Date: Thu Jul 02 2009 - 15:43:35 EST

Next message: tip-bot for Frederic Weisbecker: "[tip:perfcounters/urgent] perf_counter tools: Provide helper to print percents color"
Previous message: Alberto Gonzalez: "Re: Kernel 2.6.30 and udevd problem"
In reply to: tip-bot for Frederic Weisbecker: "[tip:perfcounters/urgent] perf_counter tools: Display percents of hits in callchain with overhead colors"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]

Commit-ID: c20ab37ef30f4a874cf27e84c12c73e584e6f5cc
Gitweb: http://git.kernel.org/tip/c20ab37ef30f4a874cf27e84c12c73e584e6f5cc
Author: Frederic Weisbecker <fweisbec@xxxxxxxxx>
AuthorDate: Thu, 2 Jul 2009 20:14:33 +0200
Committer: Ingo Molnar <mingo@xxxxxxx>
CommitDate: Thu, 2 Jul 2009 21:38:37 +0200

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@xxxxxxxxx>
Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
Cc: Mike Galbraith <efault@xxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Anton Blanchard <anton@xxxxxxxxx>
Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
LKML-Reference: <1246558475-10624-1-git-send-email-fweisbec@xxxxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxx>

---
tools/perf/builtin-report.c | 45 ++++++++++++++++++++++++++++++++----------
tools/perf/util/callchain.c | 19 ++++++++++-------
tools/perf/util/callchain.h | 6 +++-
3 files changed, 49 insertions(+), 21 deletions(-)

diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
index 0ca4638..e8c9817 100644
--- a/tools/perf/builtin-report.c
+++ b/tools/perf/builtin-report.c
@@ -60,6 +60,7 @@ static regex_t parent_regex;
static int exclude_other = 1;
static int callchain;
static enum chain_mode callchain_mode;
+static double callchain_min_percent = 0.0;

static u64 sample_type;

@@ -1224,7 +1225,7 @@ static void collapse__resort(void)

static struct rb_root output_hists;

-static void output__insert_entry(struct hist_entry *he)
+static void output__insert_entry(struct hist_entry *he, u64 min_callchain_hits)
{
struct rb_node **p = &output_hists.rb_node;
struct rb_node *parent = NULL;
@@ -1232,9 +1233,11 @@ static void output__insert_entry(struct hist_entry *he)

if (callchain) {
if (callchain_mode == FLAT)
- sort_chain_flat(&he->sorted_chain, &he->callchain);
+ sort_chain_flat(&he->sorted_chain, &he->callchain,
+ min_callchain_hits);
else if (callchain_mode == GRAPH)
- sort_chain_graph(&he->sorted_chain, &he->callchain);
+ sort_chain_graph(&he->sorted_chain, &he->callchain,
+ min_callchain_hits);
}

while (*p != NULL) {
@@ -1251,11 +1254,14 @@ static void output__insert_entry(struct hist_entry *he)
rb_insert_color(&he->rb_node, &output_hists);
}

-static void output__resort(void)
+static void output__resort(u64 total_samples)
{
struct rb_node *next;
struct hist_entry *n;
struct rb_root *tree = &hist;
+ u64 min_callchain_hits;
+
+ min_callchain_hits = total_samples * (callchain_min_percent / 100);

if (sort__need_collapse)
tree = &collapse_hists;
@@ -1267,7 +1273,7 @@ static void output__resort(void)
next = rb_next(&n->rb_node);

rb_erase(&n->rb_node, tree);
- output__insert_entry(n);
+ output__insert_entry(n, min_callchain_hits);
}
}

@@ -1801,7 +1807,7 @@ done:
dsos__fprintf(stdout);

collapse__resort();
- output__resort();
+ output__resort(total);
output__fprintf(stdout, total);

return rc;
@@ -1811,19 +1817,36 @@ static int
parse_callchain_opt(const struct option *opt __used, const char *arg,
int unset __used)
{
+ char *tok;
+ char *endptr;
+
callchain = 1;

if (!arg)
return 0;

- if (!strncmp(arg, "graph", strlen(arg)))
+ tok = strtok((char *)arg, ",");
+ if (!tok)
+ return -1;
+
+ /* get the output mode */
+ if (!strncmp(tok, "graph", strlen(arg)))
callchain_mode = GRAPH;

- else if (!strncmp(arg, "flat", strlen(arg)))
+ else if (!strncmp(tok, "flat", strlen(arg)))
callchain_mode = FLAT;
else
return -1;

+ /* get the min percentage */
+ tok = strtok(NULL, ",");
+ if (!tok)
+ return 0;
+
+ callchain_min_percent = strtod(tok, &endptr);
+ if (tok == endptr)
+ return -1;
+
return 0;
}

@@ -1850,9 +1873,9 @@ static const struct option options[] = {
"regex filter to identify parent, see: '--sort parent'"),
OPT_BOOLEAN('x', "exclude-other", &exclude_other,
"Only display entries with parent-match"),
- OPT_CALLBACK_DEFAULT('c', "callchain", NULL, "output_type",
- "Display callchains with output_type: flat, graph. "
- "Default to flat", &parse_callchain_opt, "flat"),
+ OPT_CALLBACK_DEFAULT('c', "callchain", NULL, "output_type,min_percent",
+ "Display callchains using output_type and min percent threshold. "
+ "Default: flat,0", &parse_callchain_opt, "flat,100"),
OPT_STRING('d', "dsos", &dso_list_str, "dso[,dso...]",
"only consider symbols in these dsos"),
OPT_STRING('C', "comms", &comm_list_str, "comm[,comm...]",
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 @@ rb_insert_callchain(struct rb_root *root, struct callchain_node *chain,
* 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 @@ static void __sort_chain_graph(struct callchain_node *node)
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;
}

diff --git a/tools/perf/util/callchain.h b/tools/perf/util/callchain.h
index dfa5600..f3e4776 100644
--- a/tools/perf/util/callchain.h
+++ b/tools/perf/util/callchain.h
@@ -38,6 +38,8 @@ static inline void callchain_init(struct callchain_node *node)

void append_chain(struct callchain_node *root, struct ip_callchain *chain,
struct symbol **syms);
-void sort_chain_flat(struct rb_root *rb_root, struct callchain_node *node);
-void sort_chain_graph(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);
+void sort_chain_graph(struct rb_root *rb_root, struct callchain_node *node,
+ u64 min_hit);
#endif
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

Next message: tip-bot for Frederic Weisbecker: "[tip:perfcounters/urgent] perf_counter tools: Provide helper to print percents color"
Previous message: Alberto Gonzalez: "Re: Kernel 2.6.30 and udevd problem"
In reply to: tip-bot for Frederic Weisbecker: "[tip:perfcounters/urgent] perf_counter tools: Display percents of hits in callchain with overhead colors"
Messages sorted by: [ date ] [ thread ] [ subject ] [ author ]