From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932637AbcETAMH (ORCPT ); Thu, 19 May 2016 20:12:07 -0400 Received: from mga04.intel.com ([192.55.52.120]:56177 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755096AbcETAKM (ORCPT ); Thu, 19 May 2016 20:10:12 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.26,336,1459839600"; d="scan'208";a="970786261" From: Andi Kleen To: acme@kernel.org Cc: peterz@infradead.org, jolsa@kernel.org, linux-kernel@vger.kernel.org, mingo@kernel.org, Andi Kleen Subject: [PATCH 2/8] perf/x86: Support sysfs files depending on SMT status Date: Thu, 19 May 2016 17:09:56 -0700 Message-Id: <1463703002-19686-3-git-send-email-andi@firstfloor.org> X-Mailer: git-send-email 2.5.5 In-Reply-To: <1463703002-19686-1-git-send-email-andi@firstfloor.org> References: <1463703002-19686-1-git-send-email-andi@firstfloor.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Andi Kleen Add a way to show different sysfs events attributes depending on HyperThreading is on or off. This is difficult to determine early at boot, so we just do it dynamically when the sysfs attribute is read. v2: Compute HT status only once in CPU online/offline hooks. v3: Use topology_max_smt_threads() v4: Change formatting. Avoid duplicated prototype. Signed-off-by: Andi Kleen squash! perf/x86: Support sysfs files depending on SMT status --- arch/x86/events/core.c | 23 +++++++++++++++++++++++ arch/x86/events/perf_event.h | 10 ++++++++++ include/linux/perf_event.h | 7 +++++++ 3 files changed, 40 insertions(+) diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c index 5e5e76a52f58..383657368452 100644 --- a/arch/x86/events/core.c +++ b/arch/x86/events/core.c @@ -1622,6 +1622,29 @@ ssize_t events_sysfs_show(struct device *dev, struct device_attribute *attr, cha } EXPORT_SYMBOL_GPL(events_sysfs_show); +ssize_t events_ht_sysfs_show(struct device *dev, struct device_attribute *attr, + char *page) +{ + struct perf_pmu_events_ht_attr *pmu_attr = + container_of(attr, struct perf_pmu_events_ht_attr, attr); + + /* + * Report conditional events depending on Hyper-Threading. + * + * This is overly conservative as usually the HT special + * handling is not needed if the other CPU thread is idle. + * + * Note this does not (cannot) handle the case when thread + * siblings are invisible, for example with virtualization + * if they are owned by some other guest. The user tool + * has to re-read when a thread sibling gets onlined later. + */ + return sprintf(page, "%s", + topology_max_smt_threads() > 1 ? + pmu_attr->event_str_ht : + pmu_attr->event_str_noht); +} + EVENT_ATTR(cpu-cycles, CPU_CYCLES ); EVENT_ATTR(instructions, INSTRUCTIONS ); EVENT_ATTR(cache-references, CACHE_REFERENCES ); diff --git a/arch/x86/events/perf_event.h b/arch/x86/events/perf_event.h index 8bd764df815d..e2d7285a2dac 100644 --- a/arch/x86/events/perf_event.h +++ b/arch/x86/events/perf_event.h @@ -668,6 +668,14 @@ static struct perf_pmu_events_attr event_attr_##v = { \ .event_str = str, \ }; +#define EVENT_ATTR_STR_HT(_name, v, noht, ht) \ +static struct perf_pmu_events_ht_attr event_attr_##v = { \ + .attr = __ATTR(_name, 0444, events_ht_sysfs_show, NULL),\ + .id = 0, \ + .event_str_noht = noht, \ + .event_str_ht = ht, \ +} + extern struct x86_pmu x86_pmu __read_mostly; static inline bool x86_pmu_has_lbr_callstack(void) @@ -803,6 +811,8 @@ struct attribute **merge_attr(struct attribute **a, struct attribute **b); ssize_t events_sysfs_show(struct device *dev, struct device_attribute *attr, char *page); +ssize_t events_ht_sysfs_show(struct device *dev, struct device_attribute *attr, + char *page); #ifdef CONFIG_CPU_SUP_AMD diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h index 9e1c3ada91c4..43e5a345fa8a 100644 --- a/include/linux/perf_event.h +++ b/include/linux/perf_event.h @@ -1304,6 +1304,13 @@ struct perf_pmu_events_attr { const char *event_str; }; +struct perf_pmu_events_ht_attr { + struct device_attribute attr; + u64 id; + const char *event_str_ht; + const char *event_str_noht; +}; + ssize_t perf_event_sysfs_show(struct device *dev, struct device_attribute *attr, char *page); -- 2.5.5