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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Queue-Id: DBEBAA0008 X-Rspamd-Server: rspam10 X-Stat-Signature: w336mhriggc4rka6dap33n8ofbrh1kjf X-HE-Tag: 1765866848-485643 X-HE-Meta: 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 QxRCWaJo egN9xwQ7+j8ceAQNy8Xj8x+ortXR2etl5kLQrUwE409M2B7DKv9sT6nA+cNbYzAneC/f/OVsxL+hribuwMoJFR/Cwhiy0wMGVZTSOC1HaDOA+CtWDzhKTJIDvHjnxhYRHrwSU8xWwvCax8ZMnnONIaO3JVpQUVyhDdOLLgGedUYtED71tE662TJMrEQxAWtuYzJ+i684lrbGByFpmZJCEH3rs7Do/z5BRA/1ZCwPfEpslpSEaCGdnWRscZg== 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 15/12/25 8:16 AM, Weilin Tong wrote: > Currently, when shmem mTHPs are split and swapped out via shmem_writeout(), > there are no unified statistics to trace these mTHP swpout fallback events. > This makes it difficult to analyze the prevalence of mTHP splitting and > fallback during swap operations, which is important for memory diagnostics. > > Here we add statistics counting for mTHP fallback to small pages > when splitting and swapping out in shmem_writeout(). > > Signed-off-by: Weilin Tong > Reviewed-by: Baolin Wang > --- > mm/shmem.c | 12 ++++++++++++ > 1 file changed, 12 insertions(+) > > diff --git a/mm/shmem.c b/mm/shmem.c > index 3f194c9842a8..aa624c447358 100644 > --- a/mm/shmem.c > +++ b/mm/shmem.c > @@ -1593,11 +1593,23 @@ int shmem_writeout(struct folio *folio, struct swap_iocb **plug, > } > > if (split) { > + int order; > + Could this be moved up near the 'nr_pages' declaration instead ? > try_split: > + order = folio_order(folio); > /* Ensure the subpages are still dirty */ > folio_test_set_dirty(folio); > if (split_folio_to_list(folio, folio_list)) > goto redirty; > + > +#ifdef CONFIG_TRANSPARENT_HUGEPAGE > + if (order >= HPAGE_PMD_ORDER) { > + count_memcg_folio_events(folio, THP_SWPOUT_FALLBACK, 1); > + count_vm_event(THP_SWPOUT_FALLBACK); > + } > +#endif > + count_mthp_stat(order, MTHP_STAT_SWPOUT_FALLBACK); > + > folio_clear_dirty(folio); > } > Otherwise LGTM.