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authorLinus Torvalds <torvalds@linux-foundation.org>2012-06-08 09:14:46 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2012-06-08 09:14:46 -0700
commit106544d81d88069c2df66ebdee42a4ba8fcd25e9 (patch)
tree9a6233100699c28fafde9eaa1751de7ddc173f58 /tools/perf/design.txt
parent03d8f5408235bfd2781142458e0c0671530e74e7 (diff)
parentdb0dc75d6403b6663c0eab4c6ccb672eb9b2ed72 (diff)
downloadlinux-106544d81d88069c2df66ebdee42a4ba8fcd25e9.tar.bz2
Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar: "A bit larger than what I'd wish for - half of it is due to hw driver updates to Intel Ivy-Bridge which info got recently released, cycles:pp should work there now too, amongst other things. (but we are generally making exceptions for hardware enablement of this type.) There are also callchain fixes in it - responding to mostly theoretical (but valid) concerns. The tooling side sports perf.data endianness/portability fixes which did not make it for the merge window - and various other fixes as well." * 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (26 commits) perf/x86: Check user address explicitly in copy_from_user_nmi() perf/x86: Check if user fp is valid perf: Limit callchains to 127 perf/x86: Allow multiple stacks perf/x86: Update SNB PEBS constraints perf/x86: Enable/Add IvyBridge hardware support perf/x86: Implement cycles:p for SNB/IVB perf/x86: Fix Intel shared extra MSR allocation x86/decoder: Fix bsr/bsf/jmpe decoding with operand-size prefix perf: Remove duplicate invocation on perf_event_for_each perf uprobes: Remove unnecessary check before strlist__delete perf symbols: Check for valid dso before creating map perf evsel: Fix 32 bit values endianity swap for sample_id_all header perf session: Handle endianity swap on sample_id_all header data perf symbols: Handle different endians properly during symbol load perf evlist: Pass third argument to ioctl explicitly perf tools: Update ioctl documentation for PERF_IOC_FLAG_GROUP perf tools: Make --version show kernel version instead of pull req tag perf tools: Check if callchain is corrupted perf callchain: Make callchain cursors TLS ...
Diffstat (limited to 'tools/perf/design.txt')
-rw-r--r--tools/perf/design.txt7
1 files changed, 4 insertions, 3 deletions
diff --git a/tools/perf/design.txt b/tools/perf/design.txt
index bd0bb1b1279b..67e5d0cace85 100644
--- a/tools/perf/design.txt
+++ b/tools/perf/design.txt
@@ -409,14 +409,15 @@ Counters can be enabled and disabled in two ways: via ioctl and via
prctl. When a counter is disabled, it doesn't count or generate
events but does continue to exist and maintain its count value.
-An individual counter or counter group can be enabled with
+An individual counter can be enabled with
- ioctl(fd, PERF_EVENT_IOC_ENABLE);
+ ioctl(fd, PERF_EVENT_IOC_ENABLE, 0);
or disabled with
- ioctl(fd, PERF_EVENT_IOC_DISABLE);
+ ioctl(fd, PERF_EVENT_IOC_DISABLE, 0);
+For a counter group, pass PERF_IOC_FLAG_GROUP as the third argument.
Enabling or disabling the leader of a group enables or disables the
whole group; that is, while the group leader is disabled, none of the
counters in the group will count. Enabling or disabling a member of a