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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?sshn4Ah0xQTNZBDA1uha+fMyCLfiJNhusqH0JzjrXYbveBqJUVYkHLBKzjGU?= =?us-ascii?Q?xTHwZ92wfZYlw9FCnclyo5aXmCRhoBrFLdIDy5IdVXWVROnk0sbJ96v7qHPV?= =?us-ascii?Q?rn1Ovq0AyiD8HAItAhcKmaeNOX2hwnBCTjdGP91wwH09mty5jnOycYlR5+C5?= =?us-ascii?Q?V0sPgz2SYxHhgHPuNgsBZNIqKH67otYQ91fQ7evG0V71CgasCjpdT7Qdpc1q?= =?us-ascii?Q?UT5Qmk+TsCutnVPUMumVCBC8KJzZ9qVNs+OKKDuRso8MZAduNBPAKIh9BQsW?= =?us-ascii?Q?2uyRt1FY8UfUiA/acLIseaTTQqArHWyfgLxtyFX8SdoECGyvvM72g9Bkyc8B?= =?us-ascii?Q?gYGENcc7rvwHW4cai5V22d6NSbHUvcV3+jsixHqaVZhaNgYjHR/Q9UI6mqD1?= =?us-ascii?Q?S/z7WDGlD/qYD4ouaO3BEHiKGSzN1UZ5InjcyzGIyOGEVZWDvk7vrW2/JAg9?= =?us-ascii?Q?RgUbPlTHavku60e4REGPceC0KuoFL8uQvPbrWY3BMx6eX1PKCT1PsPCxfjPp?= =?us-ascii?Q?rnWer3cWCcJm/BWeHHgbUVHBcdiD93i2J58rBUKBf+qwt/2Po5asHmm6/2oD?= =?us-ascii?Q?BHrIF0F/9Ko2/Ng8sFgs3qVpBKcmmbfdFDqV5y7rcfLmZXRg+03LWtqHjEV0?= =?us-ascii?Q?zf574jaT74W7c63oT7RF1BZfuInLn4S8F4S8Fq7jE54WtCtEExlC5OMRBoHP?= =?us-ascii?Q?6GKmqcbPu1KNxaleXvsxxNi+I4Q9+oAcAFRc+dR7YDvqNZOTVMlUUecGbYpB?= =?us-ascii?Q?tn5IAdj04QlkNraXbmdZ92a+tNmkB198vpVIsSNFQP9L+8n77D8E8FFGvaW4?= =?us-ascii?Q?RCCwFQAAdCPN9Q6lIfOJhIpdgHydCj1SkoZRafi2F1kK0M58PQgskUNubiIs?= =?us-ascii?Q?QLmWJFKz9hJEL/Vt1ir9l/nIQBoobsym+u1J+0ix4ff7MTB06JrBNOzst1Ov?= =?us-ascii?Q?TDIJmXQZW8FD/RUvsR//kA39abFMdn2ghooEW2WNK9g9eH1FasQuYFEdQ2k5?= =?us-ascii?Q?H2VjDxxL/JEG0rkvpF1HVR1/4otDp8uYDLUS43EfF5U0SD1ar1hbqLZwB50L?= =?us-ascii?Q?M00SRMzScc3hTBq8nR865UY9CVkHXXwnzz3PdvN8tCPjntT7LcmFyxmcGnT5?= =?us-ascii?Q?ypdiSQXo0xL/cKX5kXxIMDmA4KxU1GyMXrAMsOLLwdRgGsuAjjYmccCa+H5k?= =?us-ascii?Q?hfGEro4nMkF+KeyWk4Zaa3voLOv1NaSzYOlhLebbBP8KuyTfeEJK5mVNS9iA?= =?us-ascii?Q?GzFv4J8/0ftTKqgckcqnuGmNkcDXXTBJBB8/alG+HClsyvJ//z2ck1ztE+VM?= =?us-ascii?Q?6wD1U8b6WBZgOZ3UwNSxcSN6sy8d0CRdzcQuHHdghapPxv+Wvg+EERkacVbQ?= =?us-ascii?Q?qMsTVo/8M7j3ThUfvUWjK/ee9bDNQsDwY5eFAwpXwp80+5H069GQS3UFIydG?= =?us-ascii?Q?wj2Ax1nkHdYYrWmKe0+JhVYKuEhLzV+Xm5mF3mo8D5pTDK0358Ra2rlftLR3?= =?us-ascii?Q?WqK6MUkQ0ItfuXYZR3Um72XVyptro0mA6MOeLchF55olymLrfYGEaW1S1ppV?= =?us-ascii?Q?1XzntvTja/j4MerHRTE=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: f958f26f-bd96-496d-02a9-08dcec66cca1 X-MS-Exchange-CrossTenant-AuthSource: DS7PR12MB9473.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 14 Oct 2024 15:42:24.4586 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: 5ZGrobmWFAyAZIcQTLsWU2R04gDiAnK9qq5zpPJPxA+LE1WAkSP7wQWhrUAkn/q+ X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH0PR12MB7792 --=_MailMate_F42BD5BF-E6C9-4C36-8AC8-FD9B607E1EE5_= Content-Type: text/plain Content-Transfer-Encoding: quoted-printable On 14 Oct 2024, at 6:24, Baolin Wang wrote: > Khugepaged already supports collapsing file large folios (including shm= em mTHP) > by commit 7de856ffd007 ("mm: khugepaged: support shmem mTHP collapse"),= and the > control parameters in khugepaged: 'khugepaged_max_ptes_swap' and 'khuge= paged_max_ptes_none', > still compare based on PTE granularity to determine whether a file coll= apse is > needed. However, the statistics for 'present' and 'swap' in hpage_colla= pse_scan_file() > do not take into account the large folios, which may lead to incorrect = judgments > regarding the khugepaged_max_ptes_swap/none parameters, resulting in un= necessary > file collapses. > > To fix this issue, take into account the large folios' statistics for '= present' > and 'swap' variables in the hpage_collapse_scan_file(). > > Fixes: 7de856ffd007 ("mm: khugepaged: support shmem mTHP collapse") > Signed-off-by: Baolin Wang > --- > mm/khugepaged.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/mm/khugepaged.c b/mm/khugepaged.c > index ba28ba09fe89..6f8d46d107b4 100644 > --- a/mm/khugepaged.c > +++ b/mm/khugepaged.c > @@ -2267,7 +2267,7 @@ static int hpage_collapse_scan_file(struct mm_str= uct *mm, unsigned long addr, > continue; > > if (xa_is_value(folio)) { > - ++swap; > + swap +=3D 1 << xas_get_order(&xas); xas_get_order() scans xarry sibling entries to get the order. You probabl= y can call xas_get_order() outside the loop after rcu_read_lock() and use the result inside, since xas order is not changed, right? > if (cc->is_khugepaged && > swap > khugepaged_max_ptes_swap) { > result =3D SCAN_EXCEED_SWAP_PTE; > @@ -2314,7 +2314,7 @@ static int hpage_collapse_scan_file(struct mm_str= uct *mm, unsigned long addr, > * is just too costly... > */ > > - present++; > + present +=3D folio_nr_pages(folio); > > if (need_resched()) { > xas_pause(&xas); > -- = > 2.39.3 Otherwise, LGTM. Thanks. Reviewed-by: Zi Yan -- Best Regards, Yan, Zi --=_MailMate_F42BD5BF-E6C9-4C36-8AC8-FD9B607E1EE5_= Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename=signature.asc Content-Type: application/pgp-signature; name=signature.asc -----BEGIN PGP SIGNATURE----- iQJDBAEBCgAtFiEE6rR4j8RuQ2XmaZol4n+egRQHKFQFAmcNO94PHHppeUBudmlk aWEuY29tAAoJEOJ/noEUByhUINIQAKSrXf2hOdMCRgNShjg0ML7HLjWKWWv0AE2D 4gyj5nA/VUlJIghmMtS9Ztyh6xvbsdfabs8mPyXND1JNhQTd6WbR3ks7nPzRQWaX HvNJlOgBGK22H6Ie1mcDLe1YLkl8F06nYPZ8S9etdU6fsZS/g7sbYBV8iQVhFFtS HVanPGk/xsf5knq8WHmR2j3BkhVPPeKfzklQpsG1qy7SrFVU9NpZwClEIDwNuiy7 RegubwLtXzlAIapNYrd64YvyfLeCAaJjSCNtfa+vHO8RZwqrFWRt+rah1B2BK1Ys 48bp7WYsep7DWQAla7aAVHVFd0ChlPYKstWW6VXfmGfuRrY/tcUu9q33ivlbJMX0 cZTjgozTOfLuhSt48gDvsPZASdahquFnXuVBjOBeE14m3wZR9f5sV/MzD70mdfZ8 UTkYrN1G1229yT2IrnRY94HGQqdNmRbdrXdS2awJ+qA5gLYFn96JEa7WihvhNZ1f cMU9py9aV9dS/JZUoU5VmSD5LScWdp43MYzx6L7FMa1PcVFXMJPxmotm87b/ohmF NQP92zIqGYN7pTbfcnyyg6725dTk4RNrwUy5vbrDvg/Oh0EqEaXv2AOqujwlfbDK 3mBiBYcJ9KGuKOXZe7eyXWKecMBm8KEAYUkeVV2aSOy4bhiktQJCEl0R+Hizgo54 7SRLCdCY =aiPK -----END PGP SIGNATURE----- --=_MailMate_F42BD5BF-E6C9-4C36-8AC8-FD9B607E1EE5_=--