linux/tools
Yang Jihong e16c2ce7c5 perf record: Fix continue profiling after draining the buffer
Commit da231338ec ("perf record: Use an eventfd to wakeup when
done") uses eventfd() to solve a rare race where the setting and
checking of 'done' which add done_fd to pollfd.  When draining buffer,
revents of done_fd is 0 and evlist__filter_pollfd function returns a
non-zero value.  As a result, perf record does not stop profiling.

The following simple scenarios can trigger this condition:

  # sleep 10 &
  # perf record -p $!

After the sleep process exits, perf record should stop profiling and exit.
However, perf record keeps running.

If pollfd revents contains only POLLERR or POLLHUP, perf record
indicates that buffer is draining and need to stop profiling.  Use
fdarray_flag__nonfilterable() to set done eventfd to nonfilterable
objects, so that evlist__filter_pollfd() does not filter and check done
eventfd.

Fixes: da231338ec ("perf record: Use an eventfd to wakeup when done")
Signed-off-by: Yang Jihong <yangjihong1@huawei.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Tested-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: zhangjinhao2@huawei.com
Link: http://lore.kernel.org/lkml/20210205065001.23252-1-yangjihong1@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2021-02-18 13:30:09 -03:00
..
accounting
arch perf powerpc: Support exposing Performance Monitor Counter SPRs as part of extended regs 2021-02-08 16:25:00 -03:00
bootconfig tools/bootconfig: Add tracing_on support to helper scripts 2021-01-14 10:32:20 -05:00
bpf Merge remote-tracking branch 'torvalds/master' into perf/core 2021-01-20 14:35:31 -03:00
build perf cs-etm: Update ARM's CoreSight hardware tracing OpenCSD library to v1.0.0 2021-01-20 14:34:20 -03:00
cgroup blk-iocost: update iocost_monitor.py 2020-09-01 19:38:33 -06:00
debugging docs: Update documentation to reflect what TAINT_CPU_OUT_OF_SPEC means 2020-12-08 10:53:58 -07:00
edid
firewire
firmware
gpio tools: gpio: fix %llu warning in gpio-watch.c 2021-01-18 10:05:35 +01:00
hv
iio iio: add IIO_MOD_O2 modifier 2020-08-22 10:53:12 +01:00
include Merge branch 'perf/urgent' into perf/core 2021-02-16 11:52:16 -03:00
io_uring tools/io_uring: fix compile breakage 2020-09-21 07:50:58 -06:00
kvm/kvm_stat tools/kvm_stat: Exempt time-based counters 2020-12-11 19:18:51 -05:00
laptop
leds
lib tools api fs: Cache cgroupfs mount point 2021-02-17 15:09:08 -03:00
memory-model tools/memory-model: Label MP tests' producers and consumers 2020-11-06 17:25:17 -08:00
objtool objtool: Don't fail on missing symbol table 2021-01-21 15:49:58 -06:00
pci
pcmcia
perf perf record: Fix continue profiling after draining the buffer 2021-02-18 13:30:09 -03:00
power tools/power/turbostat: Fallback to an MSR read for EPB 2021-02-03 11:58:19 +01:00
scripts perf build: Support build BPF skeletons with perf 2021-01-15 15:49:07 -03:00
spi
testing Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2021-02-10 11:33:39 -08:00
thermal/tmon
time
usb tools: usb: move to tools buildsystem 2020-08-19 14:11:44 +02:00
virtio tools/virtio: add barrier for aarch64 2020-12-18 16:14:30 -05:00
vm mm: Add PG_arch_2 page flag 2020-09-04 12:46:06 +01:00
wmi
Makefile