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Shenoy" , Swapnil Sapkal , Ingo Molnar , Peter Zijlstra , Juri Lelli , Vincent Guittot , Anna-Maria Behnsen , Frederic Weisbecker , Thomas Gleixner , linux-kernel@vger.kernel.org References: <20250904041516.3046-1-kprateek.nayak@amd.com> <20250904041516.3046-4-kprateek.nayak@amd.com> From: Shrikanth Hegde Content-Language: en-US In-Reply-To: <20250904041516.3046-4-kprateek.nayak@amd.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 X-Proofpoint-ORIG-GUID: NWOjTwsZbg6f3Net1tTt7yI6GtgkkWPa X-Proofpoint-GUID: lYJwCxw0Pnbs3QzY-RwCfqJhsOVr-aS0 X-Authority-Analysis: v=2.4 cv=SdH3duRu c=1 sm=1 tr=0 ts=68d451e5 cx=c_pps a=GFwsV6G8L6GxiO2Y/PsHdQ==:117 a=GFwsV6G8L6GxiO2Y/PsHdQ==:17 a=IkcTkHD0fZMA:10 a=yJojWOMRYYMA:10 a=zd2uoN0lAAAA:8 a=e0ugSSi9uvxMxiJAq8MA:9 a=QEXdDO2ut3YA:10 a=zgiPjhLxNE0A:10 a=zZCYzV9kfG8A:10 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjUwOTIwMDAyMCBTYWx0ZWRfX8pJPcNjMwozl wv3+m8wznyHBww6UQfUEnWb9ZYeG8Hp2t9emf56npkNuZxQ83oJjDMbyaqM6hC1fTjK0zo/cVTl m1P60RsOO37LnFBOoSJhqSCL9sHFRod2YjS34CObTCLT5d1j7L3GI6zeztxWEiKQYStExfCHfnl Xu4S9jh+j5KIkol55CV0VaVqzE4HO5UKFSP7U/asZt641EQWclI/iD69aa4Af7oySCw/kSvYJX/ HaPzc7TuV6yZ/Jbe9kMb8GPtLh1fXVkOBFDXKrWUgtARC/xMzaUcO5uV6+b6cyXtv8D+uK86g2n TbfW57esq7WAdWf14l664bIWhXBLzRNNsv1JRAYeGRQAkzeqQZZxVRa3JI9MCkSnCSDv60IDtGP RdBmxHIb X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1117,Hydra:6.1.9,FMLib:17.12.80.40 definitions=2025-09-24_06,2025-09-24_01,2025-03-28_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 suspectscore=0 phishscore=0 spamscore=0 bulkscore=0 priorityscore=1501 clxscore=1015 adultscore=0 impostorscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.19.0-2507300000 definitions=main-2509200020 On 9/4/25 9:44 AM, K Prateek Nayak wrote: > "rq->nohz_tick_stopped" always follows the state of CPU on > "nohz.idle_cpus_mask". Use the local rq indicator instead of checking > for the CPU on the "idle_cpus_mask". > > Use READ_ONCE() and WRITE_ONCE() for "rq->nohz_tick_stopped" to ensure > update_nohz_stats() always sees the latest value. > Is this ever called by remote CPU? If not, is READ/WRITE ONCE is necessary? > This cleanup is necessary to avoid the number of references to the > global "nohz.idle_cpus_mask" to ease the transition to a distributed > nohz idle tracking strategy. > > No functional changes intended. > > Reviewed-by: Gautham R. Shenoy > Signed-off-by: K Prateek Nayak > ---