Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754939AbaGIKsW (ORCPT ); Wed, 9 Jul 2014 06:48:22 -0400 Received: from fw-tnat.austin.arm.com ([217.140.110.23]:54067 "EHLO collaborate-mta1.arm.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751183AbaGIKsU (ORCPT ); Wed, 9 Jul 2014 06:48:20 -0400 Message-ID: <53BD1DEC.7050305@arm.com> Date: Wed, 09 Jul 2014 11:48:12 +0100 From: Chris Redpath User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.6.0 MIME-Version: 1.0 To: Viresh Kumar CC: "tglx@linutronix.de" , "linaro-kernel@lists.linaro.org" , "fweisbec@gmail.com" , "linux-kernel@vger.kernel.org" , "preeti@linux.vnet.ibm.com" , "netdev@vger.kernel.org" , Arvind Chauhan , "David S. Miller" Subject: Re: [RFC 7/7] net: don't check for active hrtimer after adding it References: <53BD1A56.7000902@arm.com> In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/07/14 11:44, Viresh Kumar wrote: > Hi Chris, > > On 9 July 2014 16:02, Chris Redpath wrote: > >>> diff --git a/net/core/pktgen.c b/net/core/pktgen.c >>> index fc17a9d..f911acd 100644 >>> --- a/net/core/pktgen.c >>> +++ b/net/core/pktgen.c >>> @@ -2186,8 +2186,6 @@ static void spin(struct pktgen_dev *pkt_dev, ktime_t >>> spin_until) >>> do { >>> set_current_state(TASK_INTERRUPTIBLE); >>> hrtimer_start_expires(&t.timer, HRTIMER_MODE_ABS); >>> - if (!hrtimer_active(&t.timer)) >>> - t.task = NULL; >>> >>> if (likely(t.task)) >>> schedule(); >> >> >> I think this if condition can also be removed. hrtimer_init_sleeper copies >> the supplied task_struct * to the timer, which in this case is 'current'. >> The check is likely to be there in case of !active case you removed. > > Yeah, it looks like we can get rid of this. Also, > > } while (t.task && pkt_dev->running && !signal_pending(current)); > > is present in the closing "}" of do-while loop and probably we > don't need to check t.task here as well. > > And this review comment applies to patch 2/7 as well: > hrtimer: don't check for active hrtimer after adding it > > I would still wait for somebody to prove us wrong :), and will resend > it next week only. > > Thanks. > Yeah, no worries. I just happened to read it and not knowing any of the APIs had to look up what is going on. BTW, I *will* get back to you about that broadcast stuff when I get back to it myself. Other priorities at the moment again. --Chris -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/