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=-9.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 AC8F8C43219 for ; Sat, 27 Apr 2019 01:55:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8012320679 for ; Sat, 27 Apr 2019 01:55:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1556330114; bh=trqzERWZiqNnNYQ1kiHelf5ruzxq8CB73j0pVHYv0ZE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=yk9F7+ySxOTo0b5ovrbJRyF1kVFZ9O69pLd2uTSaa1Rydt+YfYgrxT0A15tkS0d4s 5yEmYvNhgoOhmMDDEJG7nPmFedDuBKsLpiyyHH1F1fBRvIp8cpkiqINExRV4hxfuoh BLYqTFC++xl7f5RvrG32TL5HT5u25nUD/K9YYChU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727941AbfD0BzN (ORCPT ); Fri, 26 Apr 2019 21:55:13 -0400 Received: from mail.kernel.org ([198.145.29.99]:42452 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727600AbfD0BjW (ORCPT ); Fri, 26 Apr 2019 21:39:22 -0400 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 8131B20B7C; Sat, 27 Apr 2019 01:39:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1556329161; bh=trqzERWZiqNnNYQ1kiHelf5ruzxq8CB73j0pVHYv0ZE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rhZ4FYAJewr0LcOGMVi2uoW6ketwpxVCtyzBnuvPguuAt+WAdDr5+D6DN168b0JZu JvcTZzkLmB/esUuii2KH94dm8g3G7gm8Z7iGF5vXIa+M95lcnKk6x0WgIYnG5TxxPa wpGCl3lFjJLdSf0uzK/hxlOvo3a5Drph6S3Otw1E= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Stephane Eranian , Peter Zijlstra , Alexander Shishkin , Arnaldo Carvalho de Melo , Jiri Olsa , Linus Torvalds , Thomas Gleixner , Vince Weaver , kan.liang@intel.com, Ingo Molnar , Sasha Levin Subject: [PATCH AUTOSEL 5.0 31/79] perf/x86/intel: Fix handling of wakeup_events for multi-entry PEBS Date: Fri, 26 Apr 2019 21:37:50 -0400 Message-Id: <20190427013838.6596-31-sashal@kernel.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20190427013838.6596-1-sashal@kernel.org> References: <20190427013838.6596-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Stephane Eranian [ Upstream commit 583feb08e7f7ac9d533b446882eb3a54737a6dbb ] When an event is programmed with attr.wakeup_events=N (N>0), it means the caller is interested in getting a user level notification after N samples have been recorded in the kernel sampling buffer. With precise events on Intel processors, the kernel uses PEBS. The kernel tries minimize sampling overhead by verifying if the event configuration is compatible with multi-entry PEBS mode. If so, the kernel is notified only when the buffer has reached its threshold. Other PEBS operates in single-entry mode, the kenrel is notified for each PEBS sample. The problem is that the current implementation look at frequency mode and event sample_type but ignores the wakeup_events field. Thus, it may not be possible to receive a notification after each precise event. This patch fixes this problem by disabling multi-entry PEBS if wakeup_events is non-zero. Signed-off-by: Stephane Eranian Signed-off-by: Peter Zijlstra (Intel) Reviewed-by: Andi Kleen Cc: Alexander Shishkin Cc: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: Vince Weaver Cc: kan.liang@intel.com Link: https://lkml.kernel.org/r/20190306195048.189514-1-eranian@google.com Signed-off-by: Ingo Molnar Signed-off-by: Sasha Levin --- arch/x86/events/intel/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c index 2480feb07df3..c647595666c2 100644 --- a/arch/x86/events/intel/core.c +++ b/arch/x86/events/intel/core.c @@ -3184,7 +3184,7 @@ static int intel_pmu_hw_config(struct perf_event *event) return ret; if (event->attr.precise_ip) { - if (!event->attr.freq) { + if (!(event->attr.freq || event->attr.wakeup_events)) { event->hw.flags |= PERF_X86_EVENT_AUTO_RELOAD; if (!(event->attr.sample_type & ~intel_pmu_large_pebs_flags(event))) -- 2.19.1