From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755585AbeCSPNs (ORCPT ); Mon, 19 Mar 2018 11:13:48 -0400 Received: from mail-yb0-f174.google.com ([209.85.213.174]:37040 "EHLO mail-yb0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755226AbeCSPNr (ORCPT ); Mon, 19 Mar 2018 11:13:47 -0400 X-Google-Smtp-Source: AG47ELs2S/9BRvIjjxFoFErF6HH7MYmW910vA6ULGQWYlZKzsYsAPn3IC9oS3QQebGh07NRthcBiPw== Date: Mon, 19 Mar 2018 08:13:43 -0700 From: Tejun Heo To: Andrew Morton Cc: Kirill Tkhai , cl@linux.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] percpu: Allow to kill tasks doing pcpu_alloc() and waiting for pcpu_balance_workfn() Message-ID: <20180319151343.GK2943022@devbig577.frc2.facebook.com> References: <152102825828.13166.9574628787314078889.stgit@localhost.localdomain> <20180314135631.3e21b31b154e9f3036fa6c52@linux-foundation.org> <20180314220909.GE2943022@devbig577.frc2.facebook.com> <20180314152203.c06fce436d221d34d3e4cf4a@linux-foundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180314152203.c06fce436d221d34d3e4cf4a@linux-foundation.org> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hello, Andrew. On Wed, Mar 14, 2018 at 03:22:03PM -0700, Andrew Morton wrote: > hm. spose so. Maybe. Are there other ways? I assume the time is > being spent in pcpu_create_chunk()? We could drop the mutex while > running that stuff and take the appropriate did-we-race-with-someone > testing after retaking it. Or similar. I'm not sure that'd change much. Ultimately, isn't the choice between being able to return NULL and waiting for more memory? If we decide to return NULL, it doesn't make difference where we do that from, right? Thanks. -- tejun