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charset="us-ascii" Content-ID: <6886988ADD4D8149924B69B6675E9FA2@prod.exchangelabs.com> Content-Transfer-Encoding: quoted-printable Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-OriginatorOrg: amperecomputing.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: BL1PR01MB7649.prod.exchangelabs.com X-MS-Exchange-CrossTenant-Network-Message-Id: eb27850a-4f71-4aa8-47de-08de3d9d2341 X-MS-Exchange-CrossTenant-originalarrivaltime: 17 Dec 2025 18:50:24.3352 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 3bc2b170-fd94-476d-b0ce-4229bdc904a7 X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: +8Gch90juk8cbthS4vg2qzhSUOJqvjmZ47KAd3K6MWmib59zfVt2bmSDZPkmT+iuiagkTBpr3Mu8ulLDYIh41rSx2y1dHuQKtNMYRywVZHY= X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA1PR01MB6624 Hi Zhan, The cleanup looks nice, but these helpers are sitting in some very critical= hot paths. `update_stats_wait_end_fair` and `update_stats_enqueue_sleeper_= fair` are hit on practically every task wakeup and context switch.=20 Even though it's not a functional refactoring, have you verified it with an= y benchmarks? I'm concerned that introducing the helper and passing around = addresses of local variables (&stats, &p) might make it harder for the comp= iler to optimize compared to the original version. I'm actually looking at a similar improvement in the PELT area, so I'd be c= urious to know if you've seen any measurable change in overhead.. To help t= he compiler, it might be better to have the helper return the stats pointer= directly rather than passing &stats. This avoids the "double indirection" = and makes it easier for the compiler to keep everything in registers. Also,= for these hot paths, using `__always_inline` would be safer than just `inl= ine` to avoid possible overhead. Thanks, Shubhang Kaushik=