From patchwork Wed Sep 27 03:31:14 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Mi, Dapeng" X-Patchwork-Id: 13399889 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 C1E08E7E62B for ; Wed, 27 Sep 2023 04:19:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229759AbjI0ETR (ORCPT ); Wed, 27 Sep 2023 00:19:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35792 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229571AbjI0ESN (ORCPT ); Wed, 27 Sep 2023 00:18:13 -0400 Received: from mgamail.intel.com (mgamail.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7EBBF140C8; Tue, 26 Sep 2023 20:24:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1695785068; x=1727321068; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=ycMyhEAn9ZsRQ3bijHZc8YDuhP6Nbbfwf7cwH5wQeXk=; b=Ui21nhBySHLPI3+/rBHlK8cKkUin8HbEVzst4AM1OTS08BsEkGj9W68y gdi/eVsv7HirOq7qYSm8ldAgqWJzlouepgwNH9mQl9vxGHJ9dslm8nqSR W5M3K03dd6DpksrEVDXkokoHZqmTnpMKDbt9OFCpAYho+U5w//4LOIbMX wx8pSfZ2G2EXiAXtNMPA8bn/IeTWgnGmVorY5JF/aFosrgJxMfdi6iozT eL/7CncQNDLW6TVmWQmYuo8BYZELK47Sqpal/BxRzQgpyKotIXYL942ba OD17CxPzn4am4FPn2YeTEjdIjxIYKgzPT583u5EzR3EjjAQFTO1++F9jn A==; X-IronPort-AV: E=McAfee;i="6600,9927,10845"; a="366780770" X-IronPort-AV: E=Sophos;i="6.03,179,1694761200"; d="scan'208";a="366780770" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Sep 2023 20:24:28 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10845"; a="864637076" X-IronPort-AV: E=Sophos;i="6.03,179,1694761200"; d="scan'208";a="864637076" Received: from dmi-pnp-i7.sh.intel.com ([10.239.159.155]) by fmsmga002.fm.intel.com with ESMTP; 26 Sep 2023 20:24:22 -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 v4 03/13] perf/core: Add function perf_event_group_leader_check() Date: Wed, 27 Sep 2023 11:31:14 +0800 Message-Id: <20230927033124.1226509-4-dapeng1.mi@linux.intel.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230927033124.1226509-1-dapeng1.mi@linux.intel.com> References: <20230927033124.1226509-1-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 4c72a41f11af..d485dac2b55f 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -12313,6 +12313,81 @@ 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 * @@ -12507,71 +12582,9 @@ 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.