Messages in this thread | | | Date | Mon, 27 Feb 2023 10:11:42 -0600 | From | David Vernet <> | Subject | Re: [PATCH] tasks: Extract rcu_users out of union |
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On Fri, Feb 17, 2023 at 11:25:21AM +0100, Oleg Nesterov wrote: > On 02/16, David Vernet wrote: > > > > On Thu, Feb 16, 2023 at 09:04:59AM +0100, Oleg Nesterov wrote: > > > > > > > a task that's successfully looked > > > > up in e.g. the pid_list with find_task_by_pid_ns(), can always have a > > > > 'usage' reference acquired on them, as it's guaranteed to be > > > > > 0 until after the next gp. > > > > > > Yes. So it seems you need another key-to-task_struct map with rcu-safe > > > lookup/get and thus the add() method needs inc_not_zero(task->rcu_users) ? > > > > Yes, exactly. > > OK, in this case I agree, inc_not_zero(rcu_users) makes sense and thus we need > this patch.
Thanks again for taking a look.
> > Just I was confused by the previous part of the changelog due to my bad English.
No worries at all -- the commit summary definitely could have been more clear.
Does anyone else have any thoughts? Is there anything else we need to do for this patch to land?
Thanks, David
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