aboutsummaryrefslogtreecommitdiff
path: root/init
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2009-09-21 09:15:07 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2009-09-21 09:15:07 -0700
commit43c1266ce4dc06bfd236cec31e11e9ecd69c0bef (patch)
tree40a86739ca4c36200f447f655b01c57cfe646e26 /init
parentb8c7f1dc5ca4e0d10709182233cdab932cef593d (diff)
parent57c0c15b5244320065374ad2c54f4fbec77a6428 (diff)
downloadlinaro-lsk-43c1266ce4dc06bfd236cec31e11e9ecd69c0bef.tar.gz
Merge branch 'perfcounters-rename-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'perfcounters-rename-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: perf: Tidy up after the big rename perf: Do the big rename: Performance Counters -> Performance Events perf_counter: Rename 'event' to event_id/hw_event perf_counter: Rename list_entry -> group_entry, counter_list -> group_list Manually resolved some fairly trivial conflicts with the tracing tree in include/trace/ftrace.h and kernel/trace/trace_syscalls.c.
Diffstat (limited to 'init')
-rw-r--r--init/Kconfig45
1 files changed, 31 insertions, 14 deletions
diff --git a/init/Kconfig b/init/Kconfig
index 0121c0ea3e0..0aa6579504c 100644
--- a/init/Kconfig
+++ b/init/Kconfig
@@ -916,31 +916,36 @@ config AIO
by some high performance threaded applications. Disabling
this option saves about 7k.
-config HAVE_PERF_COUNTERS
+config HAVE_PERF_EVENTS
bool
help
See tools/perf/design.txt for details.
-menu "Performance Counters"
+menu "Kernel Performance Events And Counters"
-config PERF_COUNTERS
- bool "Kernel Performance Counters"
- default y if PROFILING
- depends on HAVE_PERF_COUNTERS
+config PERF_EVENTS
+ bool "Kernel performance events and counters"
+ default y if (PROFILING || PERF_COUNTERS)
+ depends on HAVE_PERF_EVENTS
select ANON_INODES
help
- Enable kernel support for performance counter hardware.
+ Enable kernel support for various performance events provided
+ by software and hardware.
+
+ Software events are supported either build-in or via the
+ use of generic tracepoints.
- Performance counters are special hardware registers available
- on most modern CPUs. These registers count the number of certain
+ Most modern CPUs support performance events via performance
+ counter registers. These registers count the number of certain
types of hw events: such as instructions executed, cachemisses
suffered, or branches mis-predicted - without slowing down the
kernel or applications. These registers can also trigger interrupts
when a threshold number of events have passed - and can thus be
used to profile the code that runs on that CPU.
- The Linux Performance Counter subsystem provides an abstraction of
- these hardware capabilities, available via a system call. It
+ The Linux Performance Event subsystem provides an abstraction of
+ these software and hardware cevent apabilities, available via a
+ system call and used by the "perf" utility in tools/perf/. It
provides per task and per CPU counters, and it provides event
capabilities on top of those.
@@ -948,17 +953,29 @@ config PERF_COUNTERS
config EVENT_PROFILE
bool "Tracepoint profiling sources"
- depends on PERF_COUNTERS && EVENT_TRACING
+ depends on PERF_EVENTS && EVENT_TRACING
default y
help
- Allow the use of tracepoints as software performance counters.
+ Allow the use of tracepoints as software performance events.
- When this is enabled, you can create perf counters based on
+ When this is enabled, you can create perf events based on
tracepoints using PERF_TYPE_TRACEPOINT and the tracepoint ID
found in debugfs://tracing/events/*/*/id. (The -e/--events
option to the perf tool can parse and interpret symbolic
tracepoints, in the subsystem:tracepoint_name format.)
+config PERF_COUNTERS
+ bool "Kernel performance counters (old config option)"
+ depends on HAVE_PERF_EVENTS
+ help
+ This config has been obsoleted by the PERF_EVENTS
+ config option - please see that one for details.
+
+ It has no effect on the kernel whether you enable
+ it or not, it is a compatibility placeholder.
+
+ Say N if unsure.
+
endmenu
config VM_EVENT_COUNTERS