perf/x86: Clean up cap_user_time* setting
authorPeter Zijlstra <peterz@infradead.org>
Thu, 3 Oct 2013 14:00:14 +0000 (16:00 +0200)
committerIngo Molnar <mingo@kernel.org>
Fri, 4 Oct 2013 07:58:55 +0000 (09:58 +0200)
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

index 897783b..9d84491 100644 (file)
@@ -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);
 }
 
 /*