From: Andi Kleen <andi@firstfloor.org>
To: a.p.zijlstra@chello.nl
Cc: mingo@kernel.org, linux-kernel@vger.kernel.org,
Andi Kleen <ak@linux.intel.com>
Subject: [PATCH] perf, x86: Allow setting period 1
Date: Fri, 8 Mar 2013 15:24:30 -0800 [thread overview]
Message-ID: <1362785070-12860-1-git-send-email-andi@firstfloor.org> (raw)
From: Andi Kleen <ak@linux.intel.com>
I had some requests for setting period 1, so that every event of something
is caught. To my knowledge there is no limit to 1 on Intel hardware.
Just remove the check for minimum 2
If specific CPUs have problems we can black list them.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
---
arch/x86/kernel/cpu/perf_event.c | 5 -----
1 files changed, 0 insertions(+), 5 deletions(-)
diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c
index bf0f01a..2b394ae 100644
--- a/arch/x86/kernel/cpu/perf_event.c
+++ b/arch/x86/kernel/cpu/perf_event.c
@@ -946,11 +946,6 @@ int x86_perf_event_set_period(struct perf_event *event)
hwc->last_period = period;
ret = 1;
}
- /*
- * Quirk: certain CPUs dont like it if just 1 hw_event is left:
- */
- if (unlikely(left < 2))
- left = 2;
if (left > x86_pmu.max_period)
left = x86_pmu.max_period;
--
1.7.7.6
next reply other threads:[~2013-03-08 23:24 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-03-08 23:24 Andi Kleen [this message]
2013-03-28 15:44 ` Andi Kleen
2013-04-10 12:58 ` Ingo Molnar
2013-04-10 13:31 ` Andi Kleen
2013-04-15 11:26 ` Ingo Molnar
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