From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753733AbcD0Pqh (ORCPT ); Wed, 27 Apr 2016 11:46:37 -0400 Received: from mga02.intel.com ([134.134.136.20]:37969 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753696AbcD0Pqf (ORCPT ); Wed, 27 Apr 2016 11:46:35 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.24,542,1455004800"; d="scan'208";a="963921954" From: Alexander Shishkin To: Peter Zijlstra Cc: Thomas Gleixner , x86@kernel.org, Borislav Petkov , Ingo Molnar , linux-kernel@vger.kernel.org, vince@deater.net, eranian@google.com, Arnaldo Carvalho de Melo , Mathieu Poirier , Alexander Shishkin Subject: [PATCH v2 7/7] perf: Let userspace know if pmu supports address filters Date: Wed, 27 Apr 2016 18:44:48 +0300 Message-Id: <1461771888-10409-8-git-send-email-alexander.shishkin@linux.intel.com> X-Mailer: git-send-email 2.8.0.rc3 In-Reply-To: <1461771888-10409-1-git-send-email-alexander.shishkin@linux.intel.com> References: <1461771888-10409-1-git-send-email-alexander.shishkin@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Export an additional common attribute for PMUs that support address range filtering to let the perf userspace identify such PMUs in a uniform way. Signed-off-by: Alexander Shishkin --- kernel/events/core.c | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) diff --git a/kernel/events/core.c b/kernel/events/core.c index 606398b62a..6d07e294a7 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -8282,6 +8282,20 @@ static void free_pmu_context(struct pmu *pmu) out: mutex_unlock(&pmus_lock); } + +/* + * Let userspace know that this PMU supports address range filtering + */ +static ssize_t nr_addr_filters_show(struct device *dev, + struct device_attribute *attr, + char *page) +{ + struct pmu *pmu = dev_get_drvdata(dev); + + return snprintf(page, PAGE_SIZE - 1, "%d\n", pmu->nr_addr_filters); +} +DEVICE_ATTR_RO(nr_addr_filters); + static struct idr pmu_idr; static ssize_t @@ -8383,9 +8397,19 @@ static int pmu_dev_alloc(struct pmu *pmu) if (ret) goto free_dev; + /* for PMUs with address filters, throw in an extra attribute */ + if (pmu->nr_addr_filters) + ret = device_create_file(pmu->dev, &dev_attr_nr_addr_filters); + + if (ret) + goto del_dev; + out: return ret; +del_dev: + device_del(pmu->dev); + free_dev: put_device(pmu->dev); goto out; @@ -8521,6 +8545,8 @@ void perf_pmu_unregister(struct pmu *pmu) free_percpu(pmu->pmu_disable_count); if (pmu->type >= PERF_TYPE_MAX) idr_remove(&pmu_idr, pmu->type); + if (pmu->nr_addr_filters) + device_remove_file(pmu->dev, &dev_attr_nr_addr_filters); device_del(pmu->dev); put_device(pmu->dev); free_pmu_context(pmu); -- 2.8.0.rc3