All of lore.kernel.org
 help / color / mirror / Atom feed
From: Luwei Kang <luwei.kang@intel.com>
To: x86@kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org
Cc: peterz@infradead.org, mingo@redhat.com, acme@kernel.org,
	mark.rutland@arm.com, alexander.shishkin@linux.intel.com,
	jolsa@redhat.com, namhyung@kernel.org, tglx@linutronix.de,
	bp@alien8.de, hpa@zytor.com, pbonzini@redhat.com,
	sean.j.christopherson@intel.com, vkuznets@redhat.com,
	wanpengli@tencent.com, jmattson@google.com, joro@8bytes.org,
	pawan.kumar.gupta@linux.intel.com, ak@linux.intel.com,
	thomas.lendacky@amd.com, fenghua.yu@intel.com,
	kan.liang@linux.intel.com, like.xu@linux.intel.com
Subject: [PATCH v1 03/11] perf/x86: Expose a function to disable auto-reload
Date: Fri,  6 Mar 2020 01:56:57 +0800	[thread overview]
Message-ID: <1583431025-19802-4-git-send-email-luwei.kang@intel.com> (raw)
In-Reply-To: <1583431025-19802-1-git-send-email-luwei.kang@intel.com>

From: Kan Liang <kan.liang@linux.intel.com>

KVM needs to disable PEBS auto-reload for guest owned event to avoid
unnecessory drain_pebs() in host.

Expose a function to disable auto-reload mechanism by unset the related
flag. The function has to be invoked before event enabling, otherwise
there is no effect.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
---
 arch/x86/events/intel/core.c      | 14 ++++++++++++++
 arch/x86/include/asm/perf_event.h |  2 ++
 2 files changed, 16 insertions(+)

diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c
index ef95076..cd17601 100644
--- a/arch/x86/events/intel/core.c
+++ b/arch/x86/events/intel/core.c
@@ -3299,6 +3299,20 @@ static int core_pmu_hw_config(struct perf_event *event)
 	return intel_pmu_bts_config(event);
 }
 
+/*
+ * Disable PEBS auto-reload mechanism by unset the flag.
+ * The function has to be invoked before event enabling,
+ * otherwise there is no effect.
+ *
+ * Currently, it's used by KVM to disable PEBS auto-reload
+ * for guest owned event.
+ */
+void perf_x86_pmu_unset_auto_reload(struct perf_event *event)
+{
+	event->hw.flags &= ~PERF_X86_EVENT_AUTO_RELOAD;
+}
+EXPORT_SYMBOL_GPL(perf_x86_pmu_unset_auto_reload);
+
 static int intel_pmu_hw_config(struct perf_event *event)
 {
 	int ret = x86_pmu_hw_config(event);
diff --git a/arch/x86/include/asm/perf_event.h b/arch/x86/include/asm/perf_event.h
index 29964b0..6179234 100644
--- a/arch/x86/include/asm/perf_event.h
+++ b/arch/x86/include/asm/perf_event.h
@@ -325,6 +325,7 @@ struct perf_guest_switch_msr {
 extern void perf_get_x86_pmu_capability(struct x86_pmu_capability *cap);
 extern void perf_check_microcode(void);
 extern int x86_perf_rdpmc_index(struct perf_event *event);
+extern void perf_x86_pmu_unset_auto_reload(struct perf_event *event);
 #else
 static inline void perf_get_x86_pmu_capability(struct x86_pmu_capability *cap)
 {
@@ -333,6 +334,7 @@ static inline void perf_get_x86_pmu_capability(struct x86_pmu_capability *cap)
 
 static inline void perf_events_lapic_init(void)	{ }
 static inline void perf_check_microcode(void) { }
+static inline void perf_x86_pmu_unset_auto_reload(struct perf_event *event) { }
 #endif
 
 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_CPU_SUP_INTEL)
-- 
1.8.3.1


  parent reply	other threads:[~2020-03-05  9:59 UTC|newest]

Thread overview: 32+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-03-05 17:56 [PATCH v1 00/11] PEBS virtualization enabling via DS Luwei Kang
2020-03-05 16:51 ` Paolo Bonzini
2020-03-05 17:56 ` [PATCH v1 01/11] perf/x86/core: Support KVM to assign a dedicated counter for guest PEBS Luwei Kang
2020-03-06 13:53   ` Peter Zijlstra
2020-03-06 14:42     ` Liang, Kan
2020-03-09 10:04       ` Peter Zijlstra
2020-03-09 13:12         ` Liang, Kan
2020-03-09 15:05           ` Peter Zijlstra
2020-03-09 19:28             ` Liang, Kan
2020-03-12 10:28               ` Kang, Luwei
2020-03-26 14:03               ` Liang, Kan
2020-04-07 12:34                 ` Kang, Luwei
2020-06-12  5:28             ` Kang, Luwei
2020-06-19  9:30               ` Kang, Luwei
2020-08-20  3:32               ` Like Xu
2020-03-09 15:44         ` Andi Kleen
2020-03-05 17:56 ` [PATCH v1 02/11] perf/x86/ds: Handle guest PEBS events overflow and inject fake PMI Luwei Kang
2020-03-05 17:56 ` Luwei Kang [this message]
2020-03-05 17:56 ` [PATCH v1 04/11] KVM: x86/pmu: Decouple event enablement from event creation Luwei Kang
2020-03-05 17:56 ` [PATCH v1 05/11] KVM: x86/pmu: Add support to reprogram PEBS event for guest counters Luwei Kang
2020-03-06 16:28   ` kbuild test robot
2020-03-06 16:28     ` kbuild test robot
2020-03-09  0:58     ` Xu, Like
2020-03-09  0:58       ` Xu, Like
2020-03-05 17:57 ` [PATCH v1 06/11] KVM: x86/pmu: Implement is_pebs_via_ds_supported pmu ops Luwei Kang
2020-03-05 17:57 ` [PATCH v1 07/11] KVM: x86/pmu: Expose CPUIDs feature bits PDCM, DS, DTES64 Luwei Kang
2020-03-05 17:57 ` [PATCH v1 08/11] KVM: x86/pmu: PEBS MSRs emulation Luwei Kang
2020-03-05 17:57 ` [PATCH v1 09/11] KVM: x86/pmu: Expose PEBS feature to guest Luwei Kang
2020-03-05 17:57 ` [PATCH v1 10/11] KVM: x86/pmu: Introduce the mask value for fixed counter Luwei Kang
2020-03-05 17:57 ` [PATCH v1 11/11] KVM: x86/pmu: Adaptive PEBS virtualization enabling Luwei Kang
2020-03-05 22:48 ` [PATCH v1 00/11] PEBS virtualization enabling via DS Andi Kleen
2020-03-06  5:37   ` Kang, Luwei

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=1583431025-19802-4-git-send-email-luwei.kang@intel.com \
    --to=luwei.kang@intel.com \
    --cc=acme@kernel.org \
    --cc=ak@linux.intel.com \
    --cc=alexander.shishkin@linux.intel.com \
    --cc=bp@alien8.de \
    --cc=fenghua.yu@intel.com \
    --cc=hpa@zytor.com \
    --cc=jmattson@google.com \
    --cc=jolsa@redhat.com \
    --cc=joro@8bytes.org \
    --cc=kan.liang@linux.intel.com \
    --cc=kvm@vger.kernel.org \
    --cc=like.xu@linux.intel.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mark.rutland@arm.com \
    --cc=mingo@redhat.com \
    --cc=namhyung@kernel.org \
    --cc=pawan.kumar.gupta@linux.intel.com \
    --cc=pbonzini@redhat.com \
    --cc=peterz@infradead.org \
    --cc=sean.j.christopherson@intel.com \
    --cc=tglx@linutronix.de \
    --cc=thomas.lendacky@amd.com \
    --cc=vkuznets@redhat.com \
    --cc=wanpengli@tencent.com \
    --cc=x86@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.