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=-1.0 required=3.0 tests=MAILING_LIST_MULTI,SPF_PASS 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 B3035C4646D for ; Fri, 10 Aug 2018 10:47:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7280422404 for ; Fri, 10 Aug 2018 10:47:42 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7280422404 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727842AbeHJNRA (ORCPT ); Fri, 10 Aug 2018 09:17:00 -0400 Received: from mx3-rdu2.redhat.com ([66.187.233.73]:50424 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726963AbeHJNRA (ORCPT ); Fri, 10 Aug 2018 09:17:00 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 2B23281663CE; Fri, 10 Aug 2018 10:47:34 +0000 (UTC) Received: from krava.brq.redhat.com (unknown [10.43.17.133]) by smtp.corp.redhat.com (Postfix) with ESMTP id 0D7F32026D65; Fri, 10 Aug 2018 10:47:30 +0000 (UTC) From: Jiri Olsa To: Arnaldo Carvalho de Melo Cc: lkml , Ingo Molnar , Namhyung Kim , David Ahern , Alexander Shishkin , Peter Zijlstra , Milind Chabbi , Oleg Nesterov , Frederic Weisbecker Subject: [PATCHv3 0/5] perf/hw_breakpoint: Fix breakpoint modify Date: Fri, 10 Aug 2018 12:47:25 +0200 Message-Id: <20180810104730.3293-1-jolsa@kernel.org> X-Scanned-By: MIMEDefang 2.78 on 10.11.54.4 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.8]); Fri, 10 Aug 2018 10:47:39 +0000 (UTC) X-Greylist: inspected by milter-greylist-4.5.16 (mx1.redhat.com [10.11.55.8]); Fri, 10 Aug 2018 10:47:39 +0000 (UTC) for IP:'10.11.54.4' DOMAIN:'int-mx04.intmail.prod.int.rdu2.redhat.com' HELO:'smtp.corp.redhat.com' FROM:'jolsa@kernel.org' RCPT:'' Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org hi, Milind reported that modify_user_hw_breakpoint wouldn't allow the breakpoint changing if the new attr had 'disabled' set to true. I found a case where it actualy prevents ptrace user interface to change the breakpoint. It's described in patch 1 as perf test, patch 2 is the breakpoint code fix. I ran strace tests, nothing (new) broken there.. v3 changes: - added Oleg's ack for patch 3 - new patches 4,5 based on Oleg's suggestions replacing the v2 fallback approach by enabling the event directly after failed modification v2 changes: - added Oleg's ack for patch 2 - added new changes based on Oleg's questions plus new test code thanks, jirka --- Jiri Olsa (5): perf tests: Add breakpoint modify tests perf/hw_breakpoint: Modify breakpoint even if the new attr has disabled set perf/hw_breakpoint: Remove superfluous bp->attr.disabled = 0 perf/hw_breakpoint: Enable breakpoint in modify_user_hw_breakpoint perf/hw_breakpoint: Simplify breakpoint enable in perf_event_modify_breakpoint kernel/events/core.c | 11 ++----- kernel/events/hw_breakpoint.c | 13 ++++---- tools/perf/arch/x86/include/arch-tests.h | 1 + tools/perf/arch/x86/tests/Build | 1 + tools/perf/arch/x86/tests/arch-tests.c | 6 ++++ tools/perf/arch/x86/tests/bp-modify.c | 213 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 6 files changed, 230 insertions(+), 15 deletions(-) create mode 100644 tools/perf/arch/x86/tests/bp-modify.c