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McKenney" To: Shakeel Butt Cc: Tejun Heo , Andrew Morton , JP Kobryn , Johannes Weiner , Ying Huang , Vlastimil Babka , Alexei Starovoitov , Sebastian Andrzej Siewior , Michal =?iso-8859-1?Q?Koutn=FD?= , bpf@vger.kernel.org, linux-mm@kvack.org, cgroups@vger.kernel.org, linux-kernel@vger.kernel.org, Meta kernel team Subject: Re: [PATCH 2/2] cgroup: explain the race between updater and flusher Message-ID: <7222e3d3-95ac-448e-ae3d-26b47e29780e@paulmck-laptop> Reply-To: paulmck@kernel.org References: <20250703200012.3734798-1-shakeel.butt@linux.dev> <20250703200012.3734798-2-shakeel.butt@linux.dev> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Stat-Signature: ecebdajduri7hjn86ouezpnb3hd3f794 X-Rspam-User: X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: 67394A000A X-HE-Tag: 1751651891-47843 X-HE-Meta: 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 zUIK2OEf z2bWILHyevN8fwsU3Ew3d+ABrTX7p0Gi4RJb1zKQFCSMYR/juh667WQqlnK7v5lei/anGPJrl5fbhMLiBClY9FHDzQovGZFyRgib43ILHS1W3T6NZEqkP3ibxikhK5cJ3+F+OBGMLl+C/JPis5G/VLW+MrVdSm0hrQ1/9cyw5AWWqMYa9FAS9NNix8GhhlOXQ+kcMuRwYgO/5/aWBRAZBwxTY5qXGWGAMuflS+X5mqvpDILHG9Uu4CwJ3iJ3zlCpGQNQBvmpMUNvr/LqBhRD/ZjeV4ALOxOdR1TFaUrIfY/wcIhn2D7KKO66liA7JgrFkxqFeL47+xnVhjXg6hjS7Sk3QPONccc7TZ1IdnsJ754r1XYHqX9PzZnkw+D0z8v5rQRZ+KMqN68Rlus1gANXUdva4oTYE+bc38QS2TaJ8cJ+KBowfrfrwZRc8y+OP2CTwm+Z8KP6as//dcHUJs+hhXfeSvazYJ2ydzET4XVRdGU8ZPvvcK7bS8ZRHnl3zUiYuPN/4BVvsfpjfJFANUqlo9LKHJ3mK8SY0K9jiqTN7Tsqz2IUix29zcdIGk1mOSWwG+vgwYIjHMX5gC5Ni1m4Y/jyc4yyw/GrS5t7ASnXJnyPfCG3FIi5KClMI80TcseT8UhaT00UvCSvEPn4LYsuATYOxIYNhCaStkq9kSvi0AEdeNYZ170E5EyoSydJLDWGe3En2QLjVHbRBhue1JAxC1q9yqQ== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Fri, Jul 04, 2025 at 10:45:25AM -0700, Shakeel Butt wrote: > On Thu, Jul 03, 2025 at 09:44:58PM -0700, Paul E. McKenney wrote: > [...] > > > > > > Thanks a lot Paul for the awesome explanation. Do you think keeping > > > data_race() here would be harmful in a sense that it might cause > > > confusion in future? > > > > Yes, plus it might incorrectly suppress a KCSAN warning for a very > > real bug. So I strongly recommend removing the data_race() in this case. > > I will remove data_race() tags but keep the comments and squash into the > first one. I will keep your reviewed-by tag unless you disagree. Works for me! Thanx, Paul