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=-3.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=no 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 EA16DC47255 for ; Tue, 12 May 2020 00:09:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CD120206F5 for ; Tue, 12 May 2020 00:09:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728284AbgELAJW (ORCPT ); Mon, 11 May 2020 20:09:22 -0400 Received: from mx2.suse.de ([195.135.220.15]:34678 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725836AbgELAJV (ORCPT ); Mon, 11 May 2020 20:09:21 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id D88CFAE68; Tue, 12 May 2020 00:09:22 +0000 (UTC) From: Davidlohr Bueso To: akpm@linux-foundation.org Cc: peterz@infradead.org, oleg@redhat.com, paulmck@kernel.org, tglx@linutronix.de, linux-kernel@vger.kernel.org, dave@stgolabs.net Subject: [PATCH -next v2 0/2] kernel/sys: reduce tasklist_lock usage get/set priorities Date: Mon, 11 May 2020 17:03:51 -0700 Message-Id: <20200512000353.23653-1-dave@stgolabs.net> X-Mailer: git-send-email 2.26.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, The following are two patches that deal with removing the tasklist_lock entirely in getpriority(2), and reducing the scope of it in setpriority(2). This also aligns somewhat to what we already do with io priorities - although there both set and get rely entirely on rcu. Details in the changelog but this passes ltp tests. Please consider for v5.8. Changes from v1: - split get and set into two patches. - improved changelog. Thanks! Davidlohr Bueso (2): kernel/sys: only rely on rcu for getpriority(2) kernel/sys: do not grab tasklist_lock for sys_setpriority(PRIO_PROCESS) kernel/sys.c | 20 ++++++++++++++------ 1 file changed, 14 insertions(+), 6 deletions(-) -- 2.26.1