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charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspam-User: X-Rspamd-Queue-Id: 4BF1EC0005 X-Rspamd-Server: rspam04 X-Stat-Signature: ix6xkwr5radtk67rbp3tzeh6s5ftztjs X-HE-Tag: 1767578831-66977 X-HE-Meta: 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 5no4uX/s 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Sun, Jan 4, 2026 at 8:20=E2=80=AFPM Lance Yang wr= ote: > > On 2026/1/4 13:41, Vernon Yang wrote: > > When an mm with the MMF_DISABLE_THP_COMPLETELY flag is detected during > > scanning, directly set khugepaged_scan.mm_slot to the next mm_slot, > > reduce redundant operation. > > > > Signed-off-by: Vernon Yang > > --- > > mm/khugepaged.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/mm/khugepaged.c b/mm/khugepaged.c > > index 1ca034a5f653..d4ed0f397335 100644 > > --- a/mm/khugepaged.c > > +++ b/mm/khugepaged.c > > @@ -2541,7 +2541,7 @@ static unsigned int khugepaged_scan_mm_slot(unsig= ned int pages, int *result, > > * Release the current mm_slot if this mm is about to die, or > > * if we scanned all vmas of this mm. > > */ > > - if (hpage_collapse_test_exit(mm) || !vma) { > > + if (hpage_collapse_test_exit_or_disable(mm) || !vma) { > > /* > > * Make sure that if mm_users is reaching zero while > > * khugepaged runs here, khugepaged_exit will find > > > Let's convert hpage_collapse_test_exit() in collect_mm_slot() as well, > otherwise the mm_slot would not be freed and will be scanned again ... > > static void collect_mm_slot(struct mm_slot *slot) > { > struct mm_struct *mm =3D slot->mm; > > lockdep_assert_held(&khugepaged_mm_lock); > > if (hpage_collapse_test_exit(mm)) { <- > > hash_del(&slot->hash); > list_del(&slot->mm_node); > > mm_slot_free(mm_slot_cache, slot); > mmdrop(mm); > } > } This patch just reduces redundant operation, For a detailed discussion[1]. You already commit 5dad604809c5 ("mm/khugepaged: keep mm in mm_slot without MMF_DISABLE_THP check"), I assume there is some problem here, e.g. not can readd? data-race? etc. Can you explain the root cause? Thanks! [1] https://lore.kernel.org/linux-mm/CACZaFFOvDad09MUopairAoAjZG6X5gffMaQbn= fy0sCHGz8xSfg@mail.gmail.com -- Thanks, Vernon