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=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable 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 C6A54C11F6F for ; Mon, 12 Jul 2021 07:22:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B23B961419 for ; Mon, 12 Jul 2021 07:22:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345286AbhGLHZP (ORCPT ); Mon, 12 Jul 2021 03:25:15 -0400 Received: from mail.kernel.org ([198.145.29.99]:32916 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239452AbhGLG6Z (ORCPT ); Mon, 12 Jul 2021 02:58:25 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 803FD610CA; Mon, 12 Jul 2021 06:55:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1626072936; bh=7mIAPfZFWlrtSMP2nEPWi0DYh6syXH1MzLV13mn0kAo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=oaQrTqaTvsoWbjB1GpoJKgaYwZnlUhS1uMu+BWXaNw0xcuTR6dYs9rcv019+OHTAT VlW7bjHFRVJxyrL8Fzq1eiwBhnaPaemQovkar2CiQ9GHUJwd0NTkHD19qv5KGgPWHT UGqSk/FD2gwUZfW2FNmGswxOHheek/UFeC8SfnLw= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Robin Murphy , Will Deacon Subject: [PATCH 5.12 069/700] perf/smmuv3: Dont trample existing events with global filter Date: Mon, 12 Jul 2021 08:02:32 +0200 Message-Id: <20210712060934.463166294@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210712060924.797321836@linuxfoundation.org> References: <20210712060924.797321836@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Robin Murphy commit 4c1daba15c209b99d192f147fea3dade30f72ed2 upstream. With global filtering, we only allow an event to be scheduled if its filter settings exactly match those of any existing events, therefore it is pointless to reapply the filter in that case. Much worse, though, is that in doing that we trample the event type of counter 0 if it's already active, and never touch the appropriate PMEVTYPERn so the new event is likely not counting the right thing either. Don't do that. CC: stable@vger.kernel.org Signed-off-by: Robin Murphy Link: https://lore.kernel.org/r/32c80c0e46237f49ad8da0c9f8864e13c4a803aa.1623153312.git.robin.murphy@arm.com Signed-off-by: Will Deacon Signed-off-by: Greg Kroah-Hartman --- drivers/perf/arm_smmuv3_pmu.c | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-) --- a/drivers/perf/arm_smmuv3_pmu.c +++ b/drivers/perf/arm_smmuv3_pmu.c @@ -277,7 +277,7 @@ static int smmu_pmu_apply_event_filter(s struct perf_event *event, int idx) { u32 span, sid; - unsigned int num_ctrs = smmu_pmu->num_counters; + unsigned int cur_idx, num_ctrs = smmu_pmu->num_counters; bool filter_en = !!get_filter_enable(event); span = filter_en ? get_filter_span(event) : @@ -285,17 +285,19 @@ static int smmu_pmu_apply_event_filter(s sid = filter_en ? get_filter_stream_id(event) : SMMU_PMCG_DEFAULT_FILTER_SID; - /* Support individual filter settings */ - if (!smmu_pmu->global_filter) { + cur_idx = find_first_bit(smmu_pmu->used_counters, num_ctrs); + /* + * Per-counter filtering, or scheduling the first globally-filtered + * event into an empty PMU so idx == 0 and it works out equivalent. + */ + if (!smmu_pmu->global_filter || cur_idx == num_ctrs) { smmu_pmu_set_event_filter(event, idx, span, sid); return 0; } - /* Requested settings same as current global settings*/ - idx = find_first_bit(smmu_pmu->used_counters, num_ctrs); - if (idx == num_ctrs || - smmu_pmu_check_global_filter(smmu_pmu->events[idx], event)) { - smmu_pmu_set_event_filter(event, 0, span, sid); + /* Otherwise, must match whatever's currently scheduled */ + if (smmu_pmu_check_global_filter(smmu_pmu->events[cur_idx], event)) { + smmu_pmu_set_evtyper(smmu_pmu, idx, get_event(event)); return 0; }