Merge branch 'perfcounters-rename-for-linus' of git://git.kernel.org/pub/scm/linux...

[pandora-kernel.git] / init / Kconfig

diff --git a/init/Kconfig b/init/Kconfig
index 0121c0e..0aa6579 100644 (file)
--- 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