perf_counter: Generic per counter interrupt throttle

Introduce a generic per counter interrupt throttle.

This uses the perf_counter_overflow() quick disable to throttle a specific
counter when its going too fast when a pmu->unthrottle() method is provided
which can undo the quick disable.

Power needs to implement both the quick disable and the unthrottle method.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
LKML-Reference: <20090525153931.703093461@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 8 insertions, 0 deletions

diff --git a/kernel/sysctl.c b/kernel/sysctl.c
index 3cb1849f5989..0c4bf863afa3 100644
--- a/kernel/sysctl.c
+++ b/kernel/sysctl.c
@@ -930,6 +930,14 @@ static struct ctl_table kern_table[] = {
                 .mode           = 0644,
                 .proc_handler   = &proc_dointvec,
         },
+        {
+                .ctl_name       = CTL_UNNUMBERED,
+                .procname       = "perf_counter_int_limit",
+                .data           = &sysctl_perf_counter_limit,
+                .maxlen         = sizeof(sysctl_perf_counter_limit),
+                .mode           = 0644,
+                .proc_handler   = &proc_dointvec,
+        },
 #endif
 /*
  * NOTE: do not add new entries to this table unless you have read