Dima Kogan f7380c12ec perf script perl: Perl scripts now get a backtrace, like the python ones ... We have some infrastructure to use perl or python to analyze logs generated by perf. Prior to this patch, only the python tools had access to backtrace information. This patch makes this information available to perl scripts as well. Example: Let's look at malloc() calls made by the seq utility. First we create a probe point: $ perf probe -x /lib/x86_64-linux-gnu/libc.so.6 malloc Added new events: ... Now we run seq, while monitoring malloc() calls with perf $ perf record --call-graph=dwarf -e probe_libc:malloc seq 5 1 2 3 4 5 [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.064 MB perf.data (6 samples) ] We can use perf to look at its log to see the malloc calls and the backtrace $ perf script seq 14195 [000] 1927993.748254: probe_libc:malloc: (7f9ff8edd320) bytes=0x22 7f9ff8edd320 malloc (/lib/x86_64-linux-gnu/libc-2.22.so) 7f9ff8e8eab0 set_binding_values.part.0 (/lib/x86_64-linux-gnu/libc-2.22.so) 7f9ff8e8eda1 __bindtextdomain (/lib/x86_64-linux-gnu/libc-2.22.so) 401b22 main (/usr/bin/seq) 7f9ff8e82610 __libc_start_main (/lib/x86_64-linux-gnu/libc-2.22.so) 402799 _start (/usr/bin/seq) ... We can also use the scripting facilities. We create a skeleton perl script that simply prints out the events $ perf script -g perl generated Perl script: perf-script.pl We can then use this script to see the malloc() calls with a backtrace. Prior to this patch, the backtrace was not available to the perl scripts. $ perf script -s perf-script.pl probe_libc::malloc 0 1927993.748254260 14195 seq __probe_ip=140325052863264, bytes=34 [7f9ff8edd320] malloc [7f9ff8e8eab0] set_binding_values.part.0 [7f9ff8e8eda1] __bindtextdomain [401b22] main [7f9ff8e82610] __libc_start_main [402799] _start ... Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Link: http://lkml.kernel.org/r/87mvphzld0.fsf@secretsauce.net Signed-off-by: Dima Kogan <dima@secretsauce.net>		2016-03-30 11:14:09 -03:00
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Build	perf build: Add scripts objects building	2015-02-12 11:49:53 -03:00
trace-event-perl.c	perf script perl: Perl scripts now get a backtrace, like the python ones	2016-03-30 11:14:09 -03:00
trace-event-python.c	perf script: Fix double free on command_line	2016-03-03 11:10:37 -03:00