[tip:perf/core] perf, x86: Restrict the ANY flag

tip-bot for Peter Zijlstra
2010-03-02T14:33:17Z

Commit-ID: 320ebf09cbb6d01954c9a060266aa8e0d27f4638
Gitweb: http://git.kernel.org/tip/320ebf09cbb6d01954c9a060266aa8e0d27f4638
Author: Peter Zijlstra <a.p.zijlstra@chello.nl>
AuthorDate: Tue, 2 Mar 2010 12:35:37 +0100
Committer: Ingo Molnar <mingo@elte.hu>
CommitDate: Tue, 2 Mar 2010 15:06:46 +0100

perf, x86: Restrict the ANY flag

The ANY flag can show SMT data of another task (like 'top'),
so we want to disable it when system-wide profiling is
disabled.

Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <new-submission>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
arch/x86/kernel/cpu/perf_event.c | 3 +++
include/linux/perf_event.h | 15 +++++++++++++++
kernel/perf_event.c | 15 ---------------
3 files changed, 18 insertions(+), 15 deletions(-)

diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c
index 6531b4b..aab2e1c 100644
--- a/arch/x86/kernel/cpu/perf_event.c
+++ b/arch/x86/kernel/cpu/perf_event.c
@@ -503,6 +503,9 @@ static int __hw_perf_event_init(struct perf_event *event)
*/
if (attr->type == PERF_TYPE_RAW) {
hwc->config |= x86_pmu.raw_event(attr->config);
+ if ((hwc->config & ARCH_PERFMON_EVENTSEL_ANY) &&
+ perf_paranoid_cpu() && !capable(CAP_SYS_ADMIN))
+ return -EACCES;
return 0;
}

diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index 04f06b4..90e0521 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -857,6 +857,21 @@ extern int sysctl_perf_event_paranoid;
extern int sysctl_perf_event_mlock;
extern int sysctl_perf_event_sample_rate;

+static inline bool perf_paranoid_tracepoint_raw(void)
+{
+ return sysctl_perf_event_paranoid > -1;
+}
+
+static inline bool perf_paranoid_cpu(void)
+{
+ return sysctl_perf_event_paranoid > 0;
+}
+
+static inline bool perf_paranoid_kernel(void)
+{
+ return sysctl_perf_event_paranoid > 1;
+}
+
extern void perf_event_init(void);
extern void perf_tp_event(int event_id, u64 addr, u64 count, void *record, int entry_size);
extern void perf_bp_event(struct perf_event *event, void *data);
diff --git a/kernel/perf_event.c b/kernel/perf_event.c
index a661e79..482d5e1 100644
--- a/kernel/perf_event.c
+++ b/kernel/perf_event.c
@@ -56,21 +56,6 @@ static atomic_t nr_task_events __read_mostly;
*/
int sysctl_perf_event_paranoid __read_mostly = 1;

-static inline bool perf_paranoid_tracepoint_raw(void)
-{
- return sysctl_perf_event_paranoid > -1;
-}
-
-static inline bool perf_paranoid_cpu(void)
-{
- return sysctl_perf_event_paranoid > 0;
-}
-
-static inline bool perf_paranoid_kernel(void)
-{
- return sysctl_perf_event_paranoid > 1;
-}
-
int sysctl_perf_event_mlock __read_mostly = 512; /* 'free' kb per user */

/*