202ff9684a
We already were able to ask for callchains for a specific event: # trace -e nanosleep --call dwarf --event sched:sched_switch/call-graph=fp/ usleep 1 This would enable tracing just the "nanosleep" syscall, with callchains at syscall exit and would ask the kernel for frame pointer callchains to be enabled for the "sched:sched_switch" tracepoint event, its just that we were not resolving the callchain and printing it in 'perf trace', do it: # trace -e nanosleep --call dwarf --event sched:sched_switch/call-graph=fp/ usleep 1 0.425 ( 0.013 ms): usleep/6718 nanosleep(rqtp: 0x7ffcc1d16e20) ... 0.425 ( ): sched:sched_switch:usleep:6718 [120] S ==> swapper/2:0 [120]) __schedule+0xfe200402 ([kernel.kallsyms]) schedule+0xfe200035 ([kernel.kallsyms]) do_nanosleep+0xfe20006f ([kernel.kallsyms]) hrtimer_nanosleep+0xfe2000dc ([kernel.kallsyms]) sys_nanosleep+0xfe20007a ([kernel.kallsyms]) do_syscall_64+0xfe200062 ([kernel.kallsyms]) return_from_SYSCALL_64+0xfe200000 ([kernel.kallsyms]) __nanosleep+0xffff008b8cbe2010 (/usr/lib64/libc-2.22.so) 0.486 ( 0.073 ms): usleep/6718 ... [continued]: nanosleep()) = 0 __nanosleep+0x10 (/usr/lib64/libc-2.22.so) usleep+0x34 (/usr/lib64/libc-2.22.so) main+0x1eb (/usr/bin/usleep) __libc_start_main+0xf0 (/usr/lib64/libc-2.22.so) _start+0x29 (/usr/bin/usleep) # Pretty compact, huh? DWARF callchains for raw_syscalls:sys_exit + frame pointer callchains for a tracepoint, if your hardware supports LBR, go wild with /call-graph=lbr/, guess the next step is to lift this from 'perf script': -F, --fields <str> comma separated output fields prepend with 'type:'. Valid types: hw,sw,trace,raw. Fields: comm,tid,pid,time,cpu,event,trace,ip,sym,dso,addr,symoff,period,iregs,brstack,brstacksym,flags Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: David Ahern <dsahern@gmail.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Milian Wolff <milian.wolff@kdab.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Wang Nan <wangnan0@huawei.com> Link: http://lkml.kernel.org/n/tip-2e7yiv5hqdm8jywlmfivvx2v@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> |
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.. | ||
arch | ||
build | ||
cgroup | ||
firewire | ||
gpio | ||
hv | ||
iio | ||
include | ||
laptop/freefall | ||
lguest | ||
lib | ||
net | ||
nfsd | ||
objtool | ||
perf | ||
power | ||
scripts | ||
spi | ||
testing | ||
thermal/tmon | ||
time | ||
usb | ||
virtio | ||
vm | ||
Makefile |