Alexander Shishkin 441430eb54 perf/aux: Only update ->aux_wakeup in non-overwrite mode ... The following commit: d9a50b0256 ("perf/aux: Ensure aux_wakeup represents most recent wakeup index") changed the AUX wakeup position calculation to rounddown(), which causes a division-by-zero in AUX overwrite mode (aka "snapshot mode"). The zero denominator results from the fact that perf record doesn't set aux_watermark to anything, in which case the kernel will set it to half the AUX buffer size, but only for non-overwrite mode. In the overwrite mode aux_watermark stays zero. The good news is that, AUX overwrite mode, wakeups don't happen and related bookkeeping is not relevant, so we can simply forego the whole wakeup updates. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: will.deacon@arm.com Link: http://lkml.kernel.org/r/20170906160811.16510-1-alexander.shishkin@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>		2017-09-29 10:06:45 +02:00
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callchain.c	perf/callchain: Force USER_DS when invoking perf_callchain_user()	2017-05-10 07:54:00 +02:00
core.c	bpf: one perf event close won't free bpf program attached by another perf event	2017-09-20 14:10:29 -07:00
hw_breakpoint.c	perf: Collapse and fix event_function_call() users	2016-01-21 18:54:24 +01:00
internal.h	tracing, perf: Adjust code layout in get_recursion_context()	2017-08-25 11:04:18 +02:00
Makefile	ftrace: allow architectures to specify ftrace compile options	2015-01-29 09:19:19 +01:00
ring_buffer.c	perf/aux: Only update ->aux_wakeup in non-overwrite mode	2017-09-29 10:06:45 +02:00
uprobes.c	mm, uprobes: fix multiple free of ->uprobes_state.xol_area	2017-08-31 16:33:15 -07:00