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McKenney" To: Sebastian Andrzej Siewior Cc: Boqun Feng , Joel Fernandes , linux-kernel@vger.kernel.org, Lai Jiangshan , Josh Triplett , Steven Rostedt , Mathieu Desnoyers , tglx@linutronix.de, tj@kernel.org Subject: Re: [PATCH] srcu: Remove srcu_queue_delayed_work_on() Reply-To: paulmck@linux.ibm.com References: <20181211111238.13474-1-bigeasy@linutronix.de> <20181212014016.GA97542@google.com> <20181212140519.GA10937@tardis> <20181213150358.bgrwgpp5am5w53ie@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181213150358.bgrwgpp5am5w53ie@linutronix.de> User-Agent: Mutt/1.5.21 (2010-09-15) X-TM-AS-GCONF: 00 x-cbid: 18121315-2213-0000-0000-0000032A5693 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00010219; HX=3.00000242; KW=3.00000007; PH=3.00000004; SC=3.00000271; SDB=6.01131216; UDB=6.00587873; IPR=6.00911347; MB=3.00024681; MTD=3.00000008; XFM=3.00000015; UTC=2018-12-13 15:26:58 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 18121315-2214-0000-0000-00005C97034A Message-Id: <20181213152653.GJ4170@linux.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:,, definitions=2018-12-13_03:,, signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 lowpriorityscore=0 mlxscore=0 impostorscore=0 mlxlogscore=999 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1810050000 definitions=main-1812130133 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Dec 13, 2018 at 04:03:58PM +0100, Sebastian Andrzej Siewior wrote: > On 2018-12-12 22:05:19 [+0800], Boqun Feng wrote: > > So Jiangshan and TJ, what's your opion on this one? If we call a > > queue_work_on() at a place where that target cpu may be offlined, I > > think we have the guarantee that the work will be eventually executed > > even if the cpu is never online again, right? In other words, if a cpu > > has been online once, queue_work_on() on it will be free from racing > > with cpu hotplug. > > > > Am I right about this, or did I miss something subtle? > > tj answered this one: > https://lkml.kernel.org/r/20180919205521.GE902964@devbig004.ftw2.facebook.com I must confess that I would have felt better about that email had it been more definite than "is might just work already". ;-) Thanx, Paul