summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorFrederic Weisbecker <fweisbec@gmail.com>2010-02-28 20:51:15 +0100
committerFrederic Weisbecker <fweisbec@gmail.com>2010-02-28 20:51:15 +0100
commit1e259e0a9982078896f3404240096cbea01daca4 (patch)
treec298759ae0957b014788f8c79197c90928e69623
parent388c3aab5d4f1b0bbfe2d5f47e7cd681866bc573 (diff)
downloadlinux-stable-1e259e0a9982078896f3404240096cbea01daca4.tar.gz
linux-stable-1e259e0a9982078896f3404240096cbea01daca4.tar.bz2
linux-stable-1e259e0a9982078896f3404240096cbea01daca4.zip
hw-breakpoints: Remove stub unthrottle callback
We support event unthrottling in breakpoint events. It means that if we have more than sysctl_perf_event_sample_rate/HZ, perf will throttle, ignoring subsequent events until the next tick. So if ptrace exceeds this max rate, it will omit events, which breaks the ptrace determinism that is supposed to report every triggered breakpoints. This is likely to happen if we set sysctl_perf_event_sample_rate to 1. This patch removes support for unthrottling in breakpoint events to break throttling and restore ptrace determinism. Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: 2.6.33.x <stable@kernel.org> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: K.Prasad <prasad@linux.vnet.ibm.com> Cc: Paul Mackerras <paulus@samba.org>
-rw-r--r--arch/x86/kernel/hw_breakpoint.c5
-rw-r--r--kernel/hw_breakpoint.c1
2 files changed, 0 insertions, 6 deletions
diff --git a/arch/x86/kernel/hw_breakpoint.c b/arch/x86/kernel/hw_breakpoint.c
index bb6006e3e295..1e8ceadc0d6a 100644
--- a/arch/x86/kernel/hw_breakpoint.c
+++ b/arch/x86/kernel/hw_breakpoint.c
@@ -531,8 +531,3 @@ void hw_breakpoint_pmu_read(struct perf_event *bp)
{
/* TODO */
}
-
-void hw_breakpoint_pmu_unthrottle(struct perf_event *bp)
-{
- /* TODO */
-}
diff --git a/kernel/hw_breakpoint.c b/kernel/hw_breakpoint.c
index 967e66143e11..4d99512ee149 100644
--- a/kernel/hw_breakpoint.c
+++ b/kernel/hw_breakpoint.c
@@ -489,5 +489,4 @@ struct pmu perf_ops_bp = {
.enable = arch_install_hw_breakpoint,
.disable = arch_uninstall_hw_breakpoint,
.read = hw_breakpoint_pmu_read,
- .unthrottle = hw_breakpoint_pmu_unthrottle
};