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McKenney" Cc: kernel test robot , K Prateek Nayak , oe-lkp@lists.linux.dev, lkp@intel.com, linux-kernel@vger.kernel.org, Vincent Guittot , Phil Auld , aubrey.li@linux.intel.com, yu.c.chen@intel.com Subject: Re: [linus:master] [sched/core] 118a2cf4ce: stress-ng.schedpolicy.ops_per_sec 14.1% regression Message-ID: <20261023170023.GY2823843@noisy.programming.kicks-ass.net> References: <202610231954.51716452-lkp@intel.com> X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: On Fri, Oct 23, 2026 at 09:14:02AM -0700, Paul E. McKenney wrote: > On Fri, Oct 23, 2026 at 07:49:20PM +0800, kernel test robot wrote: > > > > > > Hello, > > > > kernel test robot noticed a 14.1% regression of stress-ng.schedpolicy.ops_per_sec on: > > > > > > commit: 118a2cf4ced60777a2408001e2b4838fed1cea55 ("sched/core: Call wakeup_preempt() for queued tasks during class change") https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git master > > > > testcase: stress-ng > > config: x86_64-rhel-9.4 > > compiler: gcc-14 > > test machine: 224 threads 2 sockets Intel(R) Xeon(R) Platinum 8480CTDX (Sapphire Rapids) with 256G memory > > parameters: > > > > nr_threads: 100% > > testtime: 60s > > test: schedpolicy > > cpufreq_governor: performance > > > > > > If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags > > | Reported-by: kernel test robot > > | Closes: https://lore.kernel.org/oe-lkp/202610231954.51716452-lkp@intel.com > > This regression is not a good thing, but this commit is fixing a real bug. I think I have a patch somewhere stuck in my review queue for -rc1 that might help with this: https://patch.msgid.link/CANGjgdmNCfm%3DSctvKZ44y8b5n8t_JSp4meX%3DDKGnG74B3g1vVw%40mail.gmail.com If not, too bad, correctness first and all that.