From: Jiri Olsa <jolsa@redhat.com>
To: Stephane Eranian <eranian@google.com>
Cc: linux-kernel@vger.kernel.org, peterz@infradead.org,
mingo@elte.hu, ak@linux.intel.com, kan.liang@intel.com,
bp@alien8.de, maria.n.dimakopoulou@gmail.com
Subject: Re: [PATCH v2 11/12] perf/x86: make HT bug workaround conditioned on HT enabled
Date: Wed, 22 Oct 2014 16:58:04 +0200 [thread overview]
Message-ID: <20141022145804.GC15126@krava.brq.redhat.com> (raw)
In-Reply-To: <1412872486-2930-12-git-send-email-eranian@google.com>
On Thu, Oct 09, 2014 at 06:34:45PM +0200, Stephane Eranian wrote:
SNIP
> --- a/arch/x86/kernel/cpu/perf_event_intel.c
> +++ b/arch/x86/kernel/cpu/perf_event_intel.c
> @@ -12,6 +12,7 @@
> #include <linux/init.h>
> #include <linux/slab.h>
> #include <linux/export.h>
> +#include <linux/watchdog.h>
>
> #include <asm/cpufeature.h>
> #include <asm/hardirq.h>
> @@ -1811,7 +1812,7 @@ intel_start_scheduling(struct cpu_hw_events *cpuc)
> /*
> * nothing needed if in group validation mode
> */
> - if (cpuc->is_fake)
> + if (cpuc->is_fake || !is_ht_workaround_enabled())
> return;
> /*
> * no exclusion needed
> @@ -1849,8 +1850,9 @@ intel_stop_scheduling(struct cpu_hw_events *cpuc)
> /*
> * nothing needed if in group validation mode
> */
> - if (cpuc->is_fake)
> + if (cpuc->is_fake || !is_ht_workaround_enabled())
> return;
Is it possible to change is_ht_workaround_enabled() result within
intel_start_scheduling and intel_stop_scheduling time frame? like
following would happen:
is_ht_workaround_enabled == 1
intel_start_scheduling -> spin_lock(&excl_cntrs->lock);
# echo 0 > /sys/devices/cpu/ht_bug_workaround
is_ht_workaround_enabled == 0
intel_stop_scheduling -> wont call spin_unlock(&excl_cntrs->lock)
for some reason I can't get HT enabled on my HSW server, so I cannot try ;-)
jirka
next prev parent reply other threads:[~2014-10-22 14:59 UTC|newest]
Thread overview: 34+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-10-09 16:34 [PATCH v2 0/12] perf/x86: implement HT leak workaround for SNB/IVB/HSW Stephane Eranian
2014-10-09 16:34 ` [PATCH v2 01/12] perf,x86: rename er_flags to flags Stephane Eranian
2014-10-09 16:34 ` [PATCH v2 02/12] perf/x86: vectorize cpuc->kfree_on_online Stephane Eranian
2014-10-09 16:34 ` [PATCH v2 03/12] perf/x86: add 3 new scheduling callbacks Stephane Eranian
2014-10-09 16:34 ` [PATCH v2 04/12] perf/x86: add index param to get_event_constraint() callback Stephane Eranian
2014-10-09 16:34 ` [PATCH v2 05/12] perf/x86: add cross-HT counter exclusion infrastructure Stephane Eranian
2014-10-21 11:17 ` Peter Zijlstra
2014-10-21 11:18 ` Peter Zijlstra
2014-10-22 15:07 ` Jiri Olsa
2014-10-22 17:25 ` Stephane Eranian
2014-10-23 7:14 ` Jiri Olsa
2014-10-09 16:34 ` [PATCH v2 06/12] perf/x86: implement cross-HT corruption bug workaround Stephane Eranian
2014-10-22 12:31 ` Jiri Olsa
2014-10-23 7:19 ` Jiri Olsa
2014-10-23 8:01 ` Stephane Eranian
2014-10-23 8:13 ` Jiri Olsa
2014-10-09 16:34 ` [PATCH v2 07/12] perf/x86: enforce HT bug workaround for SNB/IVB/HSW Stephane Eranian
2014-10-09 16:34 ` [PATCH v2 08/12] perf/x86: enforce HT bug workaround with PEBS " Stephane Eranian
2014-10-09 16:34 ` [PATCH v2 09/12] perf/x86: fix intel_get_event_constraints() for dynamic constraints Stephane Eranian
2014-10-09 16:34 ` [PATCH v2 10/12] watchdog: add watchdog enable/disable all functions Stephane Eranian
2014-10-09 16:34 ` [PATCH v2 11/12] perf/x86: make HT bug workaround conditioned on HT enabled Stephane Eranian
2014-10-22 13:27 ` Jiri Olsa
2014-10-22 14:36 ` Stephane Eranian
2014-10-22 14:58 ` Jiri Olsa [this message]
2014-10-22 16:42 ` Stephane Eranian
2014-10-09 16:34 ` [PATCH v2 12/12] perf/x86: add syfs entry to disable HT bug workaround Stephane Eranian
2014-10-21 11:25 ` [PATCH v2 0/12] perf/x86: implement HT leak workaround for SNB/IVB/HSW Peter Zijlstra
2014-10-21 12:28 ` Stephane Eranian
2014-10-21 13:03 ` Peter Zijlstra
2014-10-21 13:08 ` Stephane Eranian
2014-10-22 9:12 ` Peter Zijlstra
2014-10-22 21:04 ` Stephane Eranian
2014-10-23 8:53 ` Peter Zijlstra
2014-10-23 8:57 ` Stephane Eranian
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