From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-16.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4A06DC433ED for ; Wed, 19 May 2021 15:20:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 25BBD610CD for ; Wed, 19 May 2021 15:20:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1354705AbhESPVa (ORCPT ); Wed, 19 May 2021 11:21:30 -0400 Received: from mga07.intel.com ([134.134.136.100]:9763 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1354573AbhESPVO (ORCPT ); Wed, 19 May 2021 11:21:14 -0400 IronPort-SDR: yT06ayuj1gxGYo9CW0DnPJ3FRaS0XrtmJ0+aHCgiB/iBNqWKaCJAxGaIulj1Obf5/OzpVt1rOU eA/QRJ1PGzaQ== X-IronPort-AV: E=McAfee;i="6200,9189,9989"; a="264916866" X-IronPort-AV: E=Sophos;i="5.82,313,1613462400"; d="scan'208";a="264916866" Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 19 May 2021 08:19:54 -0700 IronPort-SDR: Bmx2MIkjYllld0UVI6qvXIaZAHO0WFYK1kYg65cx0QW4fJOL0QA28Pu+jQ0jIwGstqKUJSlR1j WIzPAgkQ/Q6w== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.82,313,1613462400"; d="scan'208";a="411775947" Received: from otc-lr-04.jf.intel.com ([10.54.39.41]) by orsmga002.jf.intel.com with ESMTP; 19 May 2021 08:19:53 -0700 From: kan.liang@linux.intel.com To: peterz@infradead.org, mingo@redhat.com, acme@kernel.org, tglx@linutronix.de, bp@alien8.de, linux-kernel@vger.kernel.org Cc: eranian@google.com, vitaly.slobodskoy@intel.com, namhyung@kernel.org, ak@linux.intel.com, Kan Liang Subject: [PATCH V4 6/6] perf: Clean up pmu specific data Date: Wed, 19 May 2021 08:06:06 -0700 Message-Id: <1621436766-112801-6-git-send-email-kan.liang@linux.intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1621436766-112801-1-git-send-email-kan.liang@linux.intel.com> References: <1621436766-112801-1-git-send-email-kan.liang@linux.intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Kan Liang The pmu specific data is saved in task_struct now. Remove it from event context structure. Remove swap_task_ctx() as well. Reviewed-by: Andi Kleen Signed-off-by: Kan Liang --- Changes since V3: - Rebase on top of the 5.13-rc2 include/linux/perf_event.h | 11 -------- kernel/events/core.c | 64 ++-------------------------------------------- 2 files changed, 2 insertions(+), 73 deletions(-) diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h index 0085b97..5624792 100644 --- a/include/linux/perf_event.h +++ b/include/linux/perf_event.h @@ -436,16 +436,6 @@ struct pmu { struct kmem_cache *task_ctx_cache; /* - * PMU specific parts of task perf event context (i.e. ctx->task_ctx_data) - * can be synchronized using this function. See Intel LBR callstack support - * implementation and Perf core context switch handling callbacks for usage - * examples. - */ - void (*swap_task_ctx) (struct perf_event_context *prev, - struct perf_event_context *next); - /* optional */ - - /* * Set up pmu-private data structures for an AUX area */ void *(*setup_aux) (struct perf_event *event, void **pages, @@ -847,7 +837,6 @@ struct perf_event_context { #ifdef CONFIG_CGROUP_PERF int nr_cgroups; /* cgroup evts */ #endif - 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 a83284b..ddebbdb 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -1273,26 +1273,11 @@ static void get_ctx(struct perf_event_context *ctx) refcount_inc(&ctx->refcount); } -static void *alloc_task_ctx_data(struct pmu *pmu) -{ - if (pmu->task_ctx_cache) - return kmem_cache_zalloc(pmu->task_ctx_cache, GFP_KERNEL); - - return NULL; -} - -static void free_task_ctx_data(struct pmu *pmu, void *task_ctx_data) -{ - if (pmu->task_ctx_cache && task_ctx_data) - kmem_cache_free(pmu->task_ctx_cache, task_ctx_data); -} - static void free_ctx(struct rcu_head *head) { struct perf_event_context *ctx; ctx = container_of(head, struct perf_event_context, rcu_head); - free_task_ctx_data(ctx->pmu, ctx->task_ctx_data); kfree(ctx); } @@ -3485,25 +3470,13 @@ static void perf_event_context_sched_out(struct task_struct *task, int ctxn, if (cpuctx->sched_cb_usage && pmu->sched_task) pmu->sched_task(ctx, task, false); - /* - * PMU specific parts of task perf context can require - * additional synchronization. As an example of such - * synchronization see implementation details of Intel - * LBR call stack data profiling; - */ - if (pmu->swap_task_ctx) - pmu->swap_task_ctx(ctx, next_ctx); - else - swap(ctx->task_ctx_data, next_ctx->task_ctx_data); - perf_pmu_enable(pmu); /* * RCU_INIT_POINTER here is safe because we've not * modified the ctx and the above modification of - * ctx->task and ctx->task_ctx_data are immaterial - * since those values are always verified under - * ctx->lock which we're now holding. + * ctx->task is immaterial since this value is always + * verified under ctx->lock which we're now holding. */ RCU_INIT_POINTER(task->perf_event_ctxp[ctxn], next_ctx); RCU_INIT_POINTER(next->perf_event_ctxp[ctxn], ctx); @@ -4630,7 +4603,6 @@ find_get_context(struct pmu *pmu, struct task_struct *task, { struct perf_event_context *ctx, *clone_ctx = NULL; struct perf_cpu_context *cpuctx; - void *task_ctx_data = NULL; unsigned long flags; int ctxn, err; int cpu = event->cpu; @@ -4654,24 +4626,12 @@ find_get_context(struct pmu *pmu, struct task_struct *task, if (ctxn < 0) goto errout; - if (event->attach_state & PERF_ATTACH_TASK_DATA) { - task_ctx_data = alloc_task_ctx_data(pmu); - if (!task_ctx_data) { - err = -ENOMEM; - goto errout; - } - } - retry: ctx = perf_lock_task_context(task, ctxn, &flags); if (ctx) { clone_ctx = unclone_ctx(ctx); ++ctx->pin_count; - if (task_ctx_data && !ctx->task_ctx_data) { - ctx->task_ctx_data = task_ctx_data; - task_ctx_data = NULL; - } raw_spin_unlock_irqrestore(&ctx->lock, flags); if (clone_ctx) @@ -4682,11 +4642,6 @@ find_get_context(struct pmu *pmu, struct task_struct *task, if (!ctx) goto errout; - if (task_ctx_data) { - ctx->task_ctx_data = task_ctx_data; - task_ctx_data = NULL; - } - err = 0; mutex_lock(&task->perf_event_mutex); /* @@ -4713,11 +4668,9 @@ find_get_context(struct pmu *pmu, struct task_struct *task, } } - free_task_ctx_data(pmu, task_ctx_data); return ctx; errout: - free_task_ctx_data(pmu, task_ctx_data); return ERR_PTR(err); } @@ -13230,18 +13183,6 @@ inherit_event(struct perf_event *parent_event, if (IS_ERR(child_event)) return child_event; - - if ((child_event->attach_state & PERF_ATTACH_TASK_DATA) && - !child_ctx->task_ctx_data) { - struct pmu *pmu = child_event->pmu; - - child_ctx->task_ctx_data = alloc_task_ctx_data(pmu); - if (!child_ctx->task_ctx_data) { - free_event(child_event); - return ERR_PTR(-ENOMEM); - } - } - /* * is_orphaned_event() and list_add_tail(&parent_event->child_list) * must be under the same lock in order to serialize against @@ -13252,7 +13193,6 @@ inherit_event(struct perf_event *parent_event, if (is_orphaned_event(parent_event) || !atomic_long_inc_not_zero(&parent_event->refcount)) { mutex_unlock(&parent_event->child_mutex); - /* task_ctx_data is freed with child_ctx */ free_event(child_event); return NULL; } -- 2.7.4