]> git.baikalelectronics.ru Git - kernel.git/commit
perf record: Fix fallback to cpu-clock on ppc
authorDavid Ahern <dsahern@gmail.com>
Tue, 8 May 2012 15:28:57 +0000 (09:28 -0600)
committerArnaldo Carvalho de Melo <acme@redhat.com>
Wed, 9 May 2012 14:57:29 +0000 (11:57 -0300)
commitfb3b52a00fa7510e72874a8790b05ee6831f6e43
tree08959d68e6f3dc9cbd4d8e14467c1bdc24ade900
parent19e26b53cc4072f1db9bb515893cfcd984e38bdb
perf record: Fix fallback to cpu-clock on ppc

perf-record on PPC is not falling back to cpu-clock:

$ perf record -ag -fo /tmp/perf.data -- sleep 1

  Error: sys_perf_event_open() syscall returned with 6 (No such device or address).  /bin/dmesg may provide additional information.

  Fatal: No CONFIG_PERF_EVENTS=y kernel support configured?

The problem is that until 2.6.37 (behavior changed with commit 0ccf41f)
perf on PPC returns ENXIO when hw_perf_event_init() fails. With this
patch we get the expected behavior:

$ perf record -ag -fo /tmp/perf.data -v -- sleep 1
Old kernel, cannot exclude guest or host samples.
The cycles event is not supported, trying to fall back to cpu-clock-ticks
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.151 MB /tmp/perf.data (~6592 samples) ]

Signed-off-by: David Ahern <dsahern@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1336490937-57106-1-git-send-email-dsahern@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
tools/perf/builtin-record.c