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From: tip-bot for Peter Zijlstra <tipbot@zytor.com>
To: linux-tip-commits@vger.kernel.org
Cc: linux-kernel@vger.kernel.org, hpa@zytor.com, mingo@kernel.org,
	peterz@infradead.org, tglx@linutronix.de
Subject: [tip:perf/core] perf/x86: Clean up cap_user_time* setting
Date: Fri, 4 Oct 2013 10:31:47 -0700	[thread overview]
Message-ID: <tip-nmgn0j0muo1r4c94vlfh23xy@git.kernel.org> (raw)

Commit-ID:  d8b11a0cbd1c66ce283eb9dabe0498dfa6483f32
Gitweb:     http://git.kernel.org/tip/d8b11a0cbd1c66ce283eb9dabe0498dfa6483f32
Author:     Peter Zijlstra <peterz@infradead.org>
AuthorDate: Thu, 3 Oct 2013 16:00:14 +0200
Committer:  Ingo Molnar <mingo@kernel.org>
CommitDate: Fri, 4 Oct 2013 09:58:55 +0200

perf/x86: Clean up cap_user_time* setting

Currently the cap_user_time_zero capability has different tests than
cap_user_time; even though they expose the exact same data.

Switch from CONSTANT && NONSTOP to sched_clock_stable to also deal
with multi cabinet machines and drop the tsc_disabled() check.. non of
this will work sanely without tsc anyway.

Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/n/tip-nmgn0j0muo1r4c94vlfh23xy@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
 arch/x86/kernel/cpu/perf_event.c | 11 +++--------
 1 file changed, 3 insertions(+), 8 deletions(-)

diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c
index 897783b..9d84491 100644
--- a/arch/x86/kernel/cpu/perf_event.c
+++ b/arch/x86/kernel/cpu/perf_event.c
@@ -1888,10 +1888,7 @@ void arch_perf_update_userpage(struct perf_event_mmap_page *userpg, u64 now)
 	userpg->cap_user_rdpmc = x86_pmu.attr_rdpmc;
 	userpg->pmc_width = x86_pmu.cntval_bits;
 
-	if (!boot_cpu_has(X86_FEATURE_CONSTANT_TSC))
-		return;
-
-	if (!boot_cpu_has(X86_FEATURE_NONSTOP_TSC))
+	if (!sched_clock_stable)
 		return;
 
 	userpg->cap_user_time = 1;
@@ -1899,10 +1896,8 @@ void arch_perf_update_userpage(struct perf_event_mmap_page *userpg, u64 now)
 	userpg->time_shift = CYC2NS_SCALE_FACTOR;
 	userpg->time_offset = this_cpu_read(cyc2ns_offset) - now;
 
-	if (sched_clock_stable && !check_tsc_disabled()) {
-		userpg->cap_user_time_zero = 1;
-		userpg->time_zero = this_cpu_read(cyc2ns_offset);
-	}
+	userpg->cap_user_time_zero = 1;
+	userpg->time_zero = this_cpu_read(cyc2ns_offset);
 }
 
 /*

             reply	other threads:[~2013-10-04 17:33 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2013-10-04 17:31 tip-bot for Peter Zijlstra [this message]
2013-10-04 18:31 ` [tip:perf/core] perf/x86: Clean up cap_user_time* setting Adrian Hunter
2013-10-04 18:55   ` Peter Zijlstra
2013-10-06  9:10     ` Ingo Molnar
2013-10-07  9:33       ` Peter Zijlstra
2013-10-07 15:59         ` Peter Zijlstra
2013-10-07 17:22       ` H. Peter Anvin
2013-10-07 17:40         ` Peter Zijlstra
2013-10-07 18:30           ` H. Peter Anvin

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