Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754721AbaBRGLB (ORCPT ); Tue, 18 Feb 2014 01:11:01 -0500 Received: from mga11.intel.com ([192.55.52.93]:43042 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754364AbaBRGHw (ORCPT ); Tue, 18 Feb 2014 01:07:52 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.97,500,1389772800"; d="scan'208";a="483239660" 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 v3 05/14] perf, core: pmu specific data for perf task context Date: Tue, 18 Feb 2014 14:07:32 +0800 Message-Id: <1392703661-15104-6-git-send-email-zheng.z.yan@intel.com> X-Mailer: git-send-email 1.8.5.3 In-Reply-To: <1392703661-15104-1-git-send-email-zheng.z.yan@intel.com> References: <1392703661-15104-1-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. Allocate memory for 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 --- 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 202e3fd..da551c5 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -898,6 +898,15 @@ 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)) { @@ -905,7 +914,7 @@ 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); } } @@ -3044,6 +3053,14 @@ 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 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/