From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756509AbaCQF6k (ORCPT ); Mon, 17 Mar 2014 01:58:40 -0400 Received: from mga02.intel.com ([134.134.136.20]:62763 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932353AbaCQF6g (ORCPT ); Mon, 17 Mar 2014 01:58:36 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.97,667,1389772800"; d="scan'208";a="473898316" From: "Yan, Zheng" To: linux-kernel@vger.kernel.org Cc: a.p.zijlstra@chello.nl, mingo@kernel.org, acme@infradead.org, eranian@google.com, andi@firstfloor.org, "Yan, Zheng" Subject: [PATCH v4 05/16] perf, core: pmu specific data for perf task context Date: Mon, 17 Mar 2014 13:57:25 +0800 Message-Id: <1395035856-15411-6-git-send-email-zheng.z.yan@intel.com> X-Mailer: git-send-email 1.8.5.3 In-Reply-To: <1395035856-15411-1-git-send-email-zheng.z.yan@intel.com> References: <1395035856-15411-1-git-send-email-zheng.z.yan@intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Introduce a new field to 'struct pmu' to specify the size of PMU specific data. If the size is not zero, also allocate memory for the PMU specific data when allocating perf task context. The PMU specific data are initialized to zeros. Later patches will use PMU specific data to save LBR stack. Signed-off-by: Yan, Zheng Reviewed-by: Stephane Eranian --- include/linux/perf_event.h | 5 +++++ kernel/events/core.c | 19 ++++++++++++++++++- 2 files changed, 23 insertions(+), 1 deletion(-) diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h index 80ddc0c..3da433d 100644 --- a/include/linux/perf_event.h +++ b/include/linux/perf_event.h @@ -252,6 +252,10 @@ struct pmu { */ void (*sched_task) (struct perf_event_context *ctx, bool sched_in); + /* + * PMU specific data size + */ + size_t task_ctx_size; }; /** @@ -493,6 +497,7 @@ struct perf_event_context { u64 generation; int pin_count; int nr_cgroups; /* cgroup evts */ + void *task_ctx_data; /* pmu specific data */ struct rcu_head rcu_head; }; diff --git a/kernel/events/core.c b/kernel/events/core.c index d07700a..f262c57 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -903,6 +903,15 @@ static void get_ctx(struct perf_event_context *ctx) WARN_ON(!atomic_inc_not_zero(&ctx->refcount)); } +static void free_ctx(struct rcu_head *head) +{ + struct perf_event_context *ctx; + + ctx = container_of(head, struct perf_event_context, rcu_head); + kfree(ctx->task_ctx_data); + kfree(ctx); +} + static void put_ctx(struct perf_event_context *ctx) { if (atomic_dec_and_test(&ctx->refcount)) { @@ -910,7 +919,7 @@ static void put_ctx(struct perf_event_context *ctx) put_ctx(ctx->parent_ctx); if (ctx->task) put_task_struct(ctx->task); - kfree_rcu(ctx, rcu_head); + call_rcu(&ctx->rcu_head, free_ctx); } } @@ -3048,6 +3057,14 @@ alloc_perf_context(struct pmu *pmu, struct task_struct *task) if (!ctx) return NULL; + if (task && pmu->task_ctx_size > 0) { + ctx->task_ctx_data = kzalloc(pmu->task_ctx_size, GFP_KERNEL); + if (!ctx->task_ctx_data) { + kfree(ctx); + return NULL; + } + } + __perf_event_init_context(ctx); if (task) { ctx->task = task; -- 1.8.5.3