On Tue, Mar 28, 2023 at 05:02:21PM +0800, Zhang Qiao wrote: > > > 在 2023/3/7 23:23, Greg KH 写道: > > On Mon, Mar 06, 2023 at 06:51:15PM +0800, Zhang Qiao wrote: > >> > >> > >> 在 2023/3/6 18:05, Greg KH 写道: > >>> On Mon, Mar 06, 2023 at 05:28:41PM +0800, Zhang Qiao wrote: > >>>> > >>>> > >>>> 在 2023/3/6 17:19, Greg KH 写道: > >>>>> On Mon, Mar 06, 2023 at 04:31:57PM +0800, Zhang Qiao wrote: > >>>>>> > >>>>>> > >>>>>> 在 2023/3/5 12:02, Sasha Levin 写道: > >>>>>>> This is a note to let you know that I've just added the patch titled > >>>>>>> > >>>>>>> sched/fair: sanitize vruntime of entity being placed > >>>>>>> > >>>>>>> to the 4.14-stable tree which can be found at: > >>>>>>> http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary > >>>>>>> > >>>>>>> The filename of the patch is: > >>>>>>> sched-fair-sanitize-vruntime-of-entity-being-placed.patch > >>>>>>> and it can be found in the queue-4.14 subdirectory. > >>>>>>> > >>>>>>> If you, or anyone else, feels it should not be added to the stable tree, > >>>>>>> please let <stable@xxxxxxxxxxxxxxx> know about it. > >>>>>>> > >>>>>>> > >>>>>>> > >>>>>>> commit 38247e1de3305a6ef644404ac818bc6129440eae > >>>>>> > >>>>>> Hi, > >>>>>> This patch has significant impact on the hackbench.throughput [1]. > >>>>>> Please don't backport this patch. > >>>>>> > >>>>>> [1] https://lore.kernel.org/lkml/202302211553.9738f304-yujie.liu@xxxxxxxxx/T/#u > >>>>> > >>>>> This link says it made hackbench.throughput faster, not slower, so why > >>>>> would we NOT want it? > >>>> > >>>> Please see this section. In some cases, this patch reset task's vruntime by mistake and > >>>> will lead to wrong results. > >>>> > >>>> > >>>> On Tue, Feb 21, 2023 at 03:34:16PM +0800, kernel test robot wrote: > >>>>> > >>>>> FYI, In addition to that, the commit also has significant impact on the following tests: > >>>>> > >>>>> +------------------+--------------------------------------------------+ > >>>>> | testcase: change | hackbench: hackbench.throughput -8.1% regression | > >>>>> | test machine | 104 threads 2 sockets (Skylake) with 192G memory | > >>>>> | test parameters | cpufreq_governor=performance | > >>>>> | | ipc=socket | > >>>>> | | iterations=4 | > >>>>> | | mode=process | > >>>>> | | nr_threads=100% | > >>>>> +------------------+--------------------------------------------------+ > >>>>> > >>>>> Details are as below: > >>> > >>> So one benchmark did better, by a lot, and one did less, by a little? > >>> Which one matters "more"> > >>> > >>> So Linus's tree now has a regression? Or not? I'm confused. We are > >> > >> Yes, Linus's tree also has a regression, and i have sent a patch[1] for fix this regression. > >> > >> > >> [1]: https://lore.kernel.org/lkml/79850642-ebac-5c23-d32d-b28737dcb91e@xxxxxxxxxx/ > >> > >> thanks. > >> Zhang qiao. > > > > Ok, I've dropped this from all stable queues now. Please let us know > > when we can pick it up again and what the fixup commit id in Linus's > > tree is when it lands there. > > Hi, > > The fixup patch has been merged into Linus's tree, its commit id is: > a53ce18cacb477dd0513c607f187d16f0fa96f71 ("sched/fair: Sanitize vruntime of entity being migrated") Wonderful, I have queued both of these up now, thank you for letting me know. greg k-h
