From patchwork Tue Aug 22 05:11:30 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Mi, Dapeng" X-Patchwork-Id: 13360156 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id AE419EE49B0 for ; Tue, 22 Aug 2023 05:04:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232587AbjHVFEP (ORCPT ); Tue, 22 Aug 2023 01:04:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54216 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232594AbjHVFEN (ORCPT ); Tue, 22 Aug 2023 01:04:13 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.100]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 67765199; Mon, 21 Aug 2023 22:04:06 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1692680646; x=1724216646; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=O8pf7f7oxoXEvzdcueT5j+AnOqZhPfLnr6A/Hm2lt40=; b=fQEyP+h7DNkDn6XOq0YNptgPbTWg9NrlsbhwB4ncUFrrNlJvZkrqT5Ld ykmmqsO6hqoAngGFmBQo7m8BsYeemFUscTY/Z1LZjrDLkN9ugCgqJpx6R pYvfJk9b5gNaTP8EMBXdFXUArrDU5CVphY+yWwg0kl7QHks7WpcnI3d7W HsS52ba8nHY/AxSZ9hFKXaT2tTeasWyH0yMqfUMzS+DFzNb38jkcUMwur UqOx9ZPxYoINB4m7peEOQTpJmgJCcsCBNeOvPtGuiN5b6fkvA7jWFDFne c8UXY9n2I+99a/z+cPZmrYj9RKw71Mvo4ji7lGxbt1YcPGFBcDFHoJQY1 Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10809"; a="440146504" X-IronPort-AV: E=Sophos;i="6.01,192,1684825200"; d="scan'208";a="440146504" Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Aug 2023 22:04:05 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10809"; a="982736713" X-IronPort-AV: E=Sophos;i="6.01,192,1684825200"; d="scan'208";a="982736713" Received: from dmi-pnp-i7.sh.intel.com ([10.239.159.155]) by fmsmga006.fm.intel.com with ESMTP; 21 Aug 2023 22:04:00 -0700 From: Dapeng Mi To: Sean Christopherson , Paolo Bonzini , Peter Zijlstra , Arnaldo Carvalho de Melo , Kan Liang , Like Xu , Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , Ian Rogers , Adrian Hunter Cc: kvm@vger.kernel.org, linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org, Zhenyu Wang , Zhang Xiong , Lv Zhiyuan , Yang Weijiang , Dapeng Mi , Dapeng Mi Subject: [PATCH RFC v3 03/13] perf/core: Add function perf_event_group_leader_check() Date: Tue, 22 Aug 2023 13:11:30 +0800 Message-Id: <20230822051140.512879-4-dapeng1.mi@linux.intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230822051140.512879-1-dapeng1.mi@linux.intel.com> References: <20230822051140.512879-1-dapeng1.mi@linux.intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Extract the group leader checking code in function sys_perf_event_open() to create a new function perf_event_group_leader_check(). The subsequent change would add a new function perf_event_create_group_kernel_counters() which is used to create group events in kernel space. The function also needs to do same check for group leader event just like function sys_perf_event_open() does. So extract the checking code into a separate function and avoid the code duplication. Signed-off-by: Dapeng Mi --- kernel/events/core.c | 143 +++++++++++++++++++++++-------------------- 1 file changed, 78 insertions(+), 65 deletions(-) diff --git a/kernel/events/core.c b/kernel/events/core.c index 78ae7b6f90fd..616391158d7c 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -12324,6 +12324,81 @@ perf_check_permission(struct perf_event_attr *attr, struct task_struct *task) return is_capable || ptrace_may_access(task, ptrace_mode); } +static int perf_event_group_leader_check(struct perf_event *group_leader, + struct perf_event *event, + struct perf_event_attr *attr, + struct perf_event_context *ctx, + struct pmu **pmu, + int *move_group) +{ + if (!group_leader) + return 0; + + /* + * Do not allow a recursive hierarchy (this new sibling + * becoming part of another group-sibling): + */ + if (group_leader->group_leader != group_leader) + return -EINVAL; + + /* All events in a group should have the same clock */ + if (group_leader->clock != event->clock) + return -EINVAL; + + /* + * Make sure we're both events for the same CPU; + * grouping events for different CPUs is broken; since + * you can never concurrently schedule them anyhow. + */ + if (group_leader->cpu != event->cpu) + return -EINVAL; + + /* + * Make sure we're both on the same context; either task or cpu. + */ + if (group_leader->ctx != ctx) + return -EINVAL; + + /* + * Only a group leader can be exclusive or pinned + */ + if (attr->exclusive || attr->pinned) + return -EINVAL; + + if (is_software_event(event) && + !in_software_context(group_leader)) { + /* + * If the event is a sw event, but the group_leader + * is on hw context. + * + * Allow the addition of software events to hw + * groups, this is safe because software events + * never fail to schedule. + * + * Note the comment that goes with struct + * perf_event_pmu_context. + */ + *pmu = group_leader->pmu_ctx->pmu; + } else if (!is_software_event(event)) { + if (is_software_event(group_leader) && + (group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { + /* + * In case the group is a pure software group, and we + * try to add a hardware event, move the whole group to + * the hardware context. + */ + *move_group = 1; + } + + /* Don't allow group of multiple hw events from different pmus */ + if (!in_software_context(group_leader) && + group_leader->pmu_ctx->pmu != *pmu) + return -EINVAL; + } + + return 0; +} + /** * sys_perf_event_open - open a performance event, associate it to a task/cpu * @@ -12518,71 +12593,9 @@ SYSCALL_DEFINE5(perf_event_open, } } - if (group_leader) { - err = -EINVAL; - - /* - * Do not allow a recursive hierarchy (this new sibling - * becoming part of another group-sibling): - */ - if (group_leader->group_leader != group_leader) - goto err_locked; - - /* All events in a group should have the same clock */ - if (group_leader->clock != event->clock) - goto err_locked; - - /* - * Make sure we're both events for the same CPU; - * grouping events for different CPUs is broken; since - * you can never concurrently schedule them anyhow. - */ - if (group_leader->cpu != event->cpu) - goto err_locked; - - /* - * Make sure we're both on the same context; either task or cpu. - */ - if (group_leader->ctx != ctx) - goto err_locked; - - /* - * Only a group leader can be exclusive or pinned - */ - if (attr.exclusive || attr.pinned) - goto err_locked; - - if (is_software_event(event) && - !in_software_context(group_leader)) { - /* - * If the event is a sw event, but the group_leader - * is on hw context. - * - * Allow the addition of software events to hw - * groups, this is safe because software events - * never fail to schedule. - * - * Note the comment that goes with struct - * perf_event_pmu_context. - */ - pmu = group_leader->pmu_ctx->pmu; - } else if (!is_software_event(event)) { - if (is_software_event(group_leader) && - (group_leader->group_caps & PERF_EV_CAP_SOFTWARE)) { - /* - * In case the group is a pure software group, and we - * try to add a hardware event, move the whole group to - * the hardware context. - */ - move_group = 1; - } - - /* Don't allow group of multiple hw events from different pmus */ - if (!in_software_context(group_leader) && - group_leader->pmu_ctx->pmu != pmu) - goto err_locked; - } - } + err = perf_event_group_leader_check(group_leader, event, &attr, ctx, &pmu, &move_group); + if (err) + goto err_locked; /* * Now that we're certain of the pmu; find the pmu_ctx.