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charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Thu, Oct 22, 2020 at 03:20:33PM -0600, Mathieu Poirier wrote: > Suzuki's depiction of the usecase is accurate. Using the pid of the process > that created the events comes out of a discussion you and I had in the common > area by the Intel booth at ELC in Edinburgh in the fall of 2018. At the time I > exposed the problem of having multiple events sharing the same HW resources and > you advised to proceed this way. Bah, I was afraid of that. I desperately tried to find correspondence on it, but alas, verbal crap doesn't end up in the Sent folder :-/ > That being said it is plausible that I did not expressed myself clearly enough > for you to understand the full extend of the problem. If that is the case we > are more than willing to revisit that solution. Do you see a better option than > what has currently been implemented? Moo... that really could've done with a comment I suppose. So then I don't understand the !->owner issue, that only happens when the task dies, which cannot be concurrent with event creation. Are you somehow accessing ->owner later? As for the kernel events.. why do you care about the actual task_struct * in there? I see you're using it to grab the task-pid, but how is that useful? _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel