[tip:perfcounters/core] perf report: Only load text symbols from kallsyms
From: tip-bot for Arnaldo Carvalho de Melo
Date: Wed May 27 2009 - 03:21:40 EST
Commit-ID: 03f6316d32738ec5eda2e6f628c12d1c01e61a87
Gitweb: http://git.kernel.org/tip/03f6316d32738ec5eda2e6f628c12d1c01e61a87
Author: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
AuthorDate: Tue, 26 May 2009 19:21:55 -0300
Committer: Ingo Molnar <mingo@xxxxxxx>
CommitDate: Wed, 27 May 2009 09:10:36 +0200
perf report: Only load text symbols from kallsyms
Just like we do for userspace when reading the symtab, reducing the
number of entries we insert on the symbols rbtree.
Before:
[acme@emilia ~]$ rm -f perf_report.perf ; perf record -o perf_report.perf perf stat perf report > /dev/null
Performance counter stats for 'perf':
218.138382 task clock ticks (msecs)
4 context switches (events)
8 CPU migrations (events)
2136 pagefaults (events)
32746212 CPU cycles (events) (scaled from 67.04%)
11961102 instructions (events) (scaled from 66.19%)
49841 cache references (events) (scaled from 21.96%)
13777 cache misses (events) (scaled from 21.98%)
Wall-clock time elapsed: 218.702477 msecs
[acme@emilia ~]$ perf report -i perf_report.perf | head
11.06 perf [.] 0x00000000000057cb /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: dso__find_symbol
9.15 perf [.] 0x00000000000056a0 /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: dso__insert_symbol
8.72 perf [k] 0xffffffff8101b1d2 intel_pmu_enable_all
8.51 perf [.] 0x0000000000006672 /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: thread__symbol_incnew
3.83 perf [k] 0xffffffff811cfc5a vsnprintf
3.40 perf [.] 0x0000000000005e33 /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: hex
3.40 perf [.] 0x0000000000005ec7 /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: hex2long
3.19 perf [k] 0xffffffff811ce1c1 number
2.77 perf [.] 0x0000000000006869 /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: threads__findnew
2.77 perf [.] 0x000000000000fde3 /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: rb_insert_color
[acme@emilia ~]$
After:
acme@emilia ~]$ rm -f perf_report.perf ; perf record -o perf_report.perf perf stat perf report > /dev/null
Performance counter stats for 'perf':
190.228511 task clock ticks (msecs)
4 context switches (events)
7 CPU migrations (events)
1625 pagefaults (events)
29578745 CPU cycles (events) (scaled from 66.92%)
10516914 instructions (events) (scaled from 66.47%)
44015 cache references (events) (scaled from 22.04%)
8248 cache misses (events) (scaled from 22.07%)
Wall-clock time elapsed: 190.816096 msecs
[acme@emilia ~]$ perf report -i perf_report.perf | head
15.99 perf [.] 0x00000000000057a9 /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: dso__find_symbol
10.87 perf [.] 0x000000000000674d /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: thread__symbol_incnew
8.74 perf [k] 0xffffffff8101b1d2 intel_pmu_enable_all
5.54 perf [.] 0x0000000000005e42 /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: hex
4.48 perf [.] 0x0000000000005ebe /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: hex2long
4.48 perf [k] 0xffffffff811cfba0 vsnprintf
3.84 perf [.] 0x00000000000056b4 /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: dso__insert_symbol
3.62 perf [.] 0x00000000000068d0 /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: threads__findnew
3.20 perf [k] 0xffffffff811ce0b3 number
2.56 perf [.] 0x0000000000006d78 /home/acme/git/linux-2.6-tip/Documentation/perf_counter/perf: __cmd_report
[acme@emilia ~]$
[ Impact: optimization ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
Cc: Mike Galbraith <efault@xxxxxx>
Cc: Paul Mackerras <paulus@xxxxxxxxx>
Cc: Corey Ashford <cjashfor@xxxxxxxxxxxxxxxxxx>
Cc: Marcelo Tosatti <mtosatti@xxxxxxxxxx>
Cc: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Cc: John Kacur <jkacur@xxxxxxxxxx>
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
LKML-Reference: <20090526222155.GJ4424@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Ingo Molnar <mingo@xxxxxxx>
---
Documentation/perf_counter/builtin-report.c | 14 +++++++++++---
1 files changed, 11 insertions(+), 3 deletions(-)
diff --git a/Documentation/perf_counter/builtin-report.c b/Documentation/perf_counter/builtin-report.c
index c517483..a55f15d 100644
--- a/Documentation/perf_counter/builtin-report.c
+++ b/Documentation/perf_counter/builtin-report.c
@@ -3,6 +3,7 @@
#include <libelf.h>
#include <gelf.h>
#include <elf.h>
+#include <ctype.h>
#include "util/list.h"
#include "util/rbtree.h"
@@ -408,13 +409,20 @@ static int load_kallsyms(void)
int len = hex2long(line, &start);
- len += 3; /* ' t ' */
- if (len >= line_len)
+ len++;
+ if (len + 2 >= line_len)
+ continue;
+
+ char symbol_type = line[len];
+ /*
+ * We're interested only in code ('T'ext)
+ */
+ if (toupper(symbol_type) != 'T')
continue;
/*
* Well fix up the end later, when we have all sorted.
*/
- struct symbol *sym = symbol__new(start, 0xdead, line + len);
+ struct symbol *sym = symbol__new(start, 0xdead, line + len + 2);
if (sym == NULL)
goto out_delete_dso;
--
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