From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752576AbeESCq7 (ORCPT ); Fri, 18 May 2018 22:46:59 -0400 Received: from mail.kernel.org ([198.145.29.99]:45090 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752361AbeESCqy (ORCPT ); Fri, 18 May 2018 22:46:54 -0400 From: Frederic Weisbecker To: LKML Cc: Frederic Weisbecker , Jiri Olsa , Namhyung Kim , Joel Fernandes , Peter Zijlstra , Linus Torvalds , Yoshinori Sato , Benjamin Herrenschmidt , Catalin Marinas , Chris Zankel , Paul Mackerras , Thomas Gleixner , Will Deacon , Michael Ellerman , Rich Felker , Ingo Molnar , Mark Rutland , Alexander Shishkin , Andy Lutomirski , Arnaldo Carvalho de Melo , Max Filippov Subject: [PATCH 11/12] perf/breakpoint: Pass new breakpoint type to modify_breakpoint_slot() Date: Sat, 19 May 2018 04:45:48 +0200 Message-Id: <1526697950-7091-12-git-send-email-frederic@kernel.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1526697950-7091-1-git-send-email-frederic@kernel.org> References: <1526697950-7091-1-git-send-email-frederic@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org We soon won't be able to rely on bp->attr anymore to get the new type of the modifying breakpoint because the new attributes are going to be copied only once we successfully modified the breakpoint slot. This will fix the current misdesigned layout where the new attr are copied to the modifying breakpoint before we actually know if the modification will be validated. In order to prepare for that, allow modify_breakpoint_slot() to take the new breakpoint type. Signed-off-by: Frederic Weisbecker Cc: Linus Torvalds Cc: Andy Lutomirski Cc: Yoshinori Sato Cc: Rich Felker Cc: Ingo Molnar Cc: Thomas Gleixner Cc: Will Deacon Cc: Mark Rutland Cc: Max Filippov Cc: Chris Zankel Cc: Catalin Marinas Cc: Benjamin Herrenschmidt Cc: Paul Mackerras Cc: Michael Ellerman Cc: Peter Zijlstra Cc: Arnaldo Carvalho de Melo Cc: Alexander Shishkin Cc: Jiri Olsa Cc: Namhyung Kim Cc: Joel Fernandes --- kernel/events/hw_breakpoint.c | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/kernel/events/hw_breakpoint.c b/kernel/events/hw_breakpoint.c index d7ed438..7840746 100644 --- a/kernel/events/hw_breakpoint.c +++ b/kernel/events/hw_breakpoint.c @@ -345,13 +345,13 @@ void release_bp_slot(struct perf_event *bp) mutex_unlock(&nr_bp_mutex); } -static int __modify_bp_slot(struct perf_event *bp, u64 old_type) +static int __modify_bp_slot(struct perf_event *bp, u64 old_type, u64 new_type) { int err; __release_bp_slot(bp, old_type); - err = __reserve_bp_slot(bp, bp->attr.bp_type); + err = __reserve_bp_slot(bp, new_type); if (err) { /* * Reserve the old_type slot back in case @@ -367,12 +367,12 @@ static int __modify_bp_slot(struct perf_event *bp, u64 old_type) return err; } -static int modify_bp_slot(struct perf_event *bp, u64 old_type) +static int modify_bp_slot(struct perf_event *bp, u64 old_type, u64 new_type) { int ret; mutex_lock(&nr_bp_mutex); - ret = __modify_bp_slot(bp, old_type); + ret = __modify_bp_slot(bp, old_type, new_type); mutex_unlock(&nr_bp_mutex); return ret; } @@ -481,7 +481,7 @@ modify_user_hw_breakpoint_check(struct perf_event *bp, struct perf_event_attr *a err = hw_breakpoint_parse(bp, attr, &hw); if (!err && modify) - err = modify_bp_slot(bp, old_type); + err = modify_bp_slot(bp, old_type, bp->attr.bp_type); if (err) { bp->attr.bp_addr = old_addr; -- 2.7.4