Hi Arnaldo,
On 1/28/2021 9:12 PM, Arnaldo Carvalho de Melo wrote:
Em Mon, Jan 25, 2021 at 07:27:50AM +0800, Jin Yao escreveu:
Other perf tool builtins have already supported dso filter.
For example,
perf report --dso, which only considers symbols in these dsos.
Now dso filter is supported for perf-script.
root@kbl-ppc:~# ./perf script --dso "[kernel.kallsyms]"
perf 18123 [000] 6142863.075104: 1 cycles:
ffffffff9ca77308 native_write_msr+0x8 ([kernel.kallsyms])
perf 18123 [000] 6142863.075107: 1 cycles:
ffffffff9ca77308 native_write_msr+0x8 ([kernel.kallsyms])
perf 18123 [000] 6142863.075108: 10 cycles:
ffffffff9ca77308 native_write_msr+0x8 ([kernel.kallsyms])
perf 18123 [000] 6142863.075109: 273 cycles:
ffffffff9ca7730a native_write_msr+0xa ([kernel.kallsyms])
perf 18123 [000] 6142863.075110: 7684 cycles:
ffffffff9ca3c9c0 native_sched_clock+0x50 ([kernel.kallsyms])
perf 18123 [000] 6142863.075112: 213017 cycles:
ffffffff9d765a92 syscall_exit_to_user_mode+0x32 ([kernel.kallsyms])
perf 18123 [001] 6142863.075156: 1 cycles:
ffffffff9ca77308 native_write_msr+0x8 ([kernel.kallsyms])
perf 18123 [001] 6142863.075158: 1 cycles:
ffffffff9ca77308 native_write_msr+0x8 ([kernel.kallsyms])
perf 18123 [001] 6142863.075159: 17 cycles:
ffffffff9ca77308 native_write_msr+0x8 ([kernel.kallsyms])
Applied, and in testing it I noticed this fix was also needed, added
just before it, please ack :-)
- Arnaldo
commit d4b6078bd58b799a8ea2a57842193504c867bee5
Author: Arnaldo Carvalho de Melo <[email protected]>
Date: Thu Jan 28 09:52:47 2021 -0300
perf tools: Fix DSO filtering when not finding a map for a sampled address
When we lookup an address and don't find a map we should filter that
sample if the user specified a list of --dso entries to filter on, fix
it.
Before:
$ perf script
sleep 274800 2843.556162: 1 cycles:u:
ffffffffbb26bff4 [unknown] ([unknown])
sleep 274800 2843.556168: 1 cycles:u:
ffffffffbb2b047d [unknown] ([unknown])
sleep 274800 2843.556171: 1 cycles:u:
ffffffffbb2706b2 [unknown] ([unknown])
sleep 274800 2843.556174: 6 cycles:u:
ffffffffbb2b0267 [unknown] ([unknown])
sleep 274800 2843.556176: 59 cycles:u:
ffffffffbb2b03b1 [unknown] ([unknown])
sleep 274800 2843.556180: 691 cycles:u:
ffffffffbb26bff4 [unknown] ([unknown])
sleep 274800 2843.556189: 9160 cycles:u:
7fa9550eeaa3 __GI___tunables_init+0xf3 (/usr/lib64/ld-2.32.so)
sleep 274800 2843.556312: 86937 cycles:u:
7fa9550e157b _dl_lookup_symbol_x+0x4b (/usr/lib64/ld-2.32.so)
$
So we have some samples we somehow didn't find in a map for, if we now
do:
$ perf report --stdio --dso /usr/lib64/ld-2.32.so
# dso: /usr/lib64/ld-2.32.so
#
# Total Lost Samples: 0
#
# Samples: 8 of event 'cycles:u'
# Event count (approx.): 96856
#
# Overhead Command Symbol
# ........ ....... ........................
#
89.76% sleep [.] _dl_lookup_symbol_x
9.46% sleep [.] __GI___tunables_init
0.71% sleep [k] 0xffffffffbb26bff4
0.06% sleep [k] 0xffffffffbb2b03b1
0.01% sleep [k] 0xffffffffbb2b0267
0.00% sleep [k] 0xffffffffbb2706b2
0.00% sleep [k] 0xffffffffbb2b047d
$
After this patch we get the right output with just entries for the DSOs
specified in --dso:
$ perf report --stdio --dso /usr/lib64/ld-2.32.so
# dso: /usr/lib64/ld-2.32.so
#
# Total Lost Samples: 0
#
# Samples: 8 of event 'cycles:u'
# Event count (approx.): 96856
#
# Overhead Command Symbol
# ........ ....... ........................
#
89.76% sleep [.] _dl_lookup_symbol_x
9.46% sleep [.] __GI___tunables_init
$
# To display the perf.data header info, please use --header/--header-only options.
#
Cc: Alexander Shishkin <[email protected]>
Cc: Andi Kleen <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jin Yao <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Kan Liang <[email protected]>
Cc: Namhyung Kim <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Fixes: 96415e4d3f5fdf9c ("perf symbols: Avoid unnecessary symbol loading when
dso list is specified")
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>
diff --git a/tools/perf/util/event.c b/tools/perf/util/event.c
index fbe8578e4c475773..208b6c141d98bb5d 100644
--- a/tools/perf/util/event.c
+++ b/tools/perf/util/event.c
@@ -692,6 +692,8 @@ int machine__resolve(struct machine *machine, struct
addr_location *al,
}
al->sym = map__find_symbol(al->map, al->addr);
+ } else if (symbol_conf.dso_list) {
+ al->filtered |= (1 << HIST_FILTER__DSO);
}
if (symbol_conf.sym_list) {
This fix guarantees the "[unknown]" dso is filtered when we enable "--dso" option (whatever the dso
list in --dso).
Acked-by: Jin Yao ([email protected]>
Thanks
Jin Yao
