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To: Tejun Heo Cc: linux-fsdevel@vger.kernel.org, cgroups@vger.kernel.org, linux-mm@kvack.org, viro@zeniv.linux.org.uk, brauner@kernel.org, jack@suse.cz, hannes@cmpxchg.org, mhocko@kernel.org, roman.gushchin@linux.dev, shakeel.butt@linux.dev, muchun.song@linux.dev, axboe@kernel.dk Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Hi, Tejun On Sat, Aug 23, 2025 at 1:56=E2=80=AFAM Tejun Heo wrote: > > Hello, > > On Fri, Aug 22, 2025 at 04:22:09PM +0800, Julian Sun wrote: > > +struct wb_wait_queue_head { > > + wait_queue_head_t waitq; > > + wb_wait_wakeup_func_t wb_wakeup_func; > > +}; > > wait_queue_head_t itself already allows overriding the wakeup function. > Please look for init_wait_func() usages in the tree. Hopefully, that shou= ld > contain the changes within memcg. Sorry for having misunderstood what you meant before. I=E2=80=99m afraid th= at init_wait_func() cannot work the same way. Because calling init_wait_func() presupposes that we are preparing to wait for an event(like wb_wait_completion()), but waiting for such an event might lead to a hung task. Please correct me if I'm wrong. > > Thanks. > > -- > tejun Thanks, --=20 Julian Sun