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charset=us-ascii Content-Disposition: inline In-Reply-To: <20250107030415.721474-1-surenb@google.com> User-Agent: NeoMutt/20170113 (1.7.2) X-Rspam-User: X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: CA6CF180006 X-Stat-Signature: 4whjd76t6ym4pig8hz5rczsdbqqh9h93 X-HE-Tag: 1736252892-926302 X-HE-Meta: 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 LP16QiVv 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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 Mon, Jan 06, 2025 at 07:04:15PM -0800, Suren Baghdasaryan wrote: >Since we limit vm_refcnt at VMA_REF_LIMIT and it's smaller than >VMA_LOCK_OFFSET, there is no need to check again if VMA_LOCK_OFFSET bit >is set. Remove the extra check and add a clarifying comment. > >Fixes: e8f32ff00a66 ("mm: replace vm_lock and detached flag with a reference count") >Suggested-by: Wei Yang >Signed-off-by: Suren Baghdasaryan Reviewed-by: Wei Yang >--- >Applies over mm-unstable > > include/linux/mm.h | 9 ++++++--- > 1 file changed, 6 insertions(+), 3 deletions(-) > >diff --git a/include/linux/mm.h b/include/linux/mm.h >index 486638d22fc6..b5f262fc7dc5 100644 >--- a/include/linux/mm.h >+++ b/include/linux/mm.h >@@ -747,7 +747,11 @@ static inline bool vma_start_read(struct mm_struct *mm, struct vm_area_struct *v > > > rwsem_acquire_read(&vma->vmlock_dep_map, 0, 0, _RET_IP_); >- /* Limit at VMA_REF_LIMIT to leave one count for a writer */ >+ /* >+ * Limit at VMA_REF_LIMIT to leave one count for a writer. >+ * If VMA_LOCK_OFFSET is set, __refcount_inc_not_zero_limited() will fail >+ * because VMA_REF_LIMIT is less than VMA_LOCK_OFFSET. >+ */ > if (unlikely(!__refcount_inc_not_zero_limited(&vma->vm_refcnt, &oldcnt, > VMA_REF_LIMIT))) { > rwsem_release(&vma->vmlock_dep_map, _RET_IP_); >@@ -766,8 +770,7 @@ static inline bool vma_start_read(struct mm_struct *mm, struct vm_area_struct *v > * after it has been unlocked. > * This pairs with RELEASE semantics in vma_end_write_all(). > */ >- if (unlikely(oldcnt & VMA_LOCK_OFFSET || >- vma->vm_lock_seq == raw_read_seqcount(&mm->mm_lock_seq))) { >+ if (unlikely(vma->vm_lock_seq == raw_read_seqcount(&mm->mm_lock_seq))) { > vma_refcount_put(vma); > return false; > } > >base-commit: f349e79bfbf3abfade8011797ff6d0d47b67dab7 >-- >2.47.1.613.gc27f4b7a9f-goog -- Wei Yang Help you, Help me