From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752609Ab1JONOG (ORCPT ); Sat, 15 Oct 2011 09:14:06 -0400 Received: from mail-bw0-f46.google.com ([209.85.214.46]:45415 "EHLO mail-bw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752433Ab1JONOE (ORCPT ); Sat, 15 Oct 2011 09:14:04 -0400 From: Manfred Spraul To: LKML , Andrew Morton Cc: Thomas Gleixner , Mike Galbraith , Peter Zijlstra , Manfred Spraul Subject: [PATCH 0/5] ipc/sem.c: multiple fixes Date: Sat, 15 Oct 2011 15:21:19 +0200 Message-Id: <1318684879-1887-1-git-send-email-manfred@colorfullife.com> X-Mailer: git-send-email 1.7.6.4 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi all, The wakeup scheme used by semtimedop() does not work as intended on -rt. The following series: - fixes one bug that I noticed while thinking about a -rt compatible implementation - prevents the code from returning to user space due to spurious wakeups. (noticed by Peter Zijlstra) - moves private structures from include/linux/sem.h to ipc/sem.c - saves some memory if sysvipc is disabled. - reworks the wakeup scheme and adds a 2nd wakeup scheme that is based on a completion. For CONFIG_PREEMPT_RT_BASE, this scheme is used. What do you think? The rework of the wakeup should also help to convert the code to using the wake_up_list framework. Andrew: Could you replace the patches in -mm with this series? I would prefer to keep the current scheme as the default, it's ~5% faster (6.5 usec vs. 6.8 usec per wakeup). The patches pass checkpatch.pl and I didn't observe any problems with my test apps. -- Manfred