Peter Zijlstra c3c87e7704 perf: Tighten (and fix) the grouping condition ... The fix from 9fc81d8742 ("perf: Fix events installation during moving group") was incomplete in that it failed to recognise that creating a group with events for different CPUs is semantically broken -- they cannot be co-scheduled. Furthermore, it leads to real breakage where, when we create an event for CPU Y and then migrate it to form a group on CPU X, the code gets confused where the counter is programmed -- triggered in practice as well by me via the perf fuzzer. Fix this by tightening the rules for creating groups. Only allow grouping of counters that can be co-scheduled in the same context. This means for the same task and/or the same cpu. Fixes: 9fc81d8742 ("perf: Fix events installation during moving group") Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Link: http://lkml.kernel.org/r/20150123125834.090683288@infradead.org Signed-off-by: Ingo Molnar <mingo@kernel.org>		2015-01-28 13:17:35 +01:00
..
callchain.c	Merge branch 'for-3.18-consistent-ops' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu	2014-10-15 07:48:18 +02:00
core.c	perf: Tighten (and fix) the grouping condition	2015-01-28 13:17:35 +01:00
hw_breakpoint.c	perf: Fix and clean up initialization of pmu::event_idx	2014-10-28 10:51:01 +01:00
internal.h
Makefile
ring_buffer.c
uprobes.c	Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux	2014-12-15 15:52:01 -08:00