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Thu, 30 Oct 2025 08:04:44 -0700 (PDT) Received: from DESKTOP-8TIG9K0.localdomain ([119.28.20.50]) by smtp.gmail.com with ESMTPSA id d9443c01a7336-29498d274b6sm188234395ad.59.2025.10.30.08.04.28 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 30 Oct 2025 08:04:44 -0700 (PDT) From: Xie Yuanbin To: david@redhat.com Cc: acme@kernel.org, adrian.hunter@intel.com, agordeev@linux.ibm.com, akpm@linux-foundation.org, alex@ghiti.fr, alexander.shishkin@linux.intel.com, andreas@gaisler.com, anna-maria@linutronix.de, aou@eecs.berkeley.edu, borntraeger@linux.ibm.com, bp@alien8.de, bsegall@google.com, dave.hansen@linux.intel.com, davem@davemloft.net, dietmar.eggemann@arm.com, frederic@kernel.org, gor@linux.ibm.com, hca@linux.ibm.com, hpa@zytor.com, irogers@google.com, jolsa@kernel.org, juri.lelli@redhat.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-perf-users@vger.kernel.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linux@armlinux.org.uk, lorenzo.stoakes@oracle.com, luto@kernel.org, mark.rutland@arm.com, mathieu.desnoyers@efficios.com, max.kellermann@ionos.com, mgorman@suse.de, mingo@redhat.com, namhyung@kernel.org, nysal@linux.ibm.com, palmer@dabbelt.com, paulmck@kernel.org, peterz@infradead.org, pjw@kernel.org, qq570070308@gmail.com, riel@surriel.com, rostedt@goodmis.org, ryan.roberts@arm.com, segher@kernel.crashing.org, sparclinux@vger.kernel.org, svens@linux.ibm.com, tglx@linutronix.de, thuth@redhat.com, urezki@gmail.com, vincent.guittot@linaro.org, vschneid@redhat.com, will@kernel.org, x86@kernel.org Subject: Re: [PATCH 0/3] Optimize code generation during context Date: Thu, 30 Oct 2025 23:04:17 +0800 Message-ID: <20251030150417.684-1-qq570070308@gmail.com> X-Mailer: git-send-email 2.51.0 In-Reply-To: References: MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20251030_080446_836133_D586CCCB X-CRM114-Status: GOOD ( 12.68 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org On Wed, 29 Oct 2025 11:26:39 +0100, David Hildenbrand wrote: >> I did some testing using my devices, >> and the testing logic is as follows: >> ``` >> - return finish_task_switch(prev); >> + start_time = rdtsc(); >> + barrier(); >> + rq = finish_task_switch(prev); >> + barrier(); >> + end_time = rdtsc; >> + return rq; >> ``` >> >> The test data is as follows: >> 1. mitigations Off, without patches: 13.5 - 13.7 >> 2. mitigations Off, with patches: 13.5 - 13.7 >> 3. mitigations On, without patches: 23.3 - 23.6 >> 4. mitigations On, with patches: 16.6 - 16.8 > > Such numbers absolutely have to be part of the relevant patches / cover > letter to show that the compiler is not actually smart enough to make a > good decision. This was indeed my oversight; I did not read the submitting-patches documentation carefully, thank you for your pointing it out, and I deeply apologize for this. Do I need to send the V2 version patches to supplement the relevant data? By the way, the above data was tested in WSL. I did a more detailed test on a physical machine. If possible, this data may be more appropriate: Link: https://lore.kernel.org/20251027152100.62906-1-qq570070308@gmail.com > Cheers > > David / dhildenb Thanks very much. Xie Yuanbin _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv