perf_counter: change event definition
commit4c9e25428ff46b968a30f1dfafdba550cb6e4141
authorPeter Zijlstra <a.p.zijlstra@chello.nl>
Mon, 6 Apr 2009 09:45:09 +0000 (6 11:45 +0200)
committerIngo Molnar <mingo@elte.hu>
Tue, 7 Apr 2009 08:48:59 +0000 (7 10:48 +0200)
tree273e74f4f99dc626ddb960f0cbbe9b64d47bbfe9
parent0c593b3411341e3a05a61f5527df36ab02bd11e8
perf_counter: change event definition

Currently the definition of an event is slightly ambiguous. We have
wakeup events, for poll() and SIGIO, which are either generated
when a record crosses a page boundary (hw_events.wakeup_events == 0),
or every wakeup_events new records.

Now a record can be either a counter overflow record, or a number of
different things, like the mmap PROT_EXEC region notifications.

Then there is the PERF_COUNTER_IOC_REFRESH event limit, which only
considers counter overflows.

This patch changes then wakeup_events and SIGIO notification to only
consider overflow events. Furthermore it changes the SIGIO notification
to report SIGHUP when the event limit is reached and the counter will
be disabled.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
LKML-Reference: <20090406094518.266679874@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
include/linux/perf_counter.h
kernel/perf_counter.c