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charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: B3BD114002B X-Stat-Signature: ya9wrytr6g6wor4afnrra8cw75f5351n X-Rspam-User: X-HE-Tag: 1721050240-348728 X-HE-Meta: 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 2XUjs9WF XlCQkKIUV+N5RcGs8pWivzHgNG8U59g1wV6lV5sK/UEGUlvFWHdysf9uexQhlipYvNkoVlFDhGybfnOXQ9Tjz4dQSJw3n4y60q7zN5jzwOJTkZPgWcsOKOXr/t3peMPGt3rjb84eOFDqUbUmzeRsi6N/NvexHlg/9PEWtFNGfXRwss0T/EQ6q4Mw7RSY5urMphpTgfbbl+s/txmvZi/2pJy4VTR9CsOt0MA2G X-Bogosity: Ham, tests=bogofilter, spamicity=0.000001, 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 13/07/2024 14:24, Baolin Wang wrote: > Move the suitable huge orders validation into shmem_suitable_orders() for > tmpfs, which can reuse some code to simplify the logic. > > In addition, we don't have special handling for the error code -E2BIG when > checking for conflicts with PMD sized THP in the pagecache for tmpfs, instead, > it will just fallback to order-0 allocations like this patch does, so this > simplification will not add functional changes. > > Signed-off-by: Baolin Wang Reviewed-by: Ryan Roberts > --- > mm/shmem.c | 39 +++++++++++++++------------------------ > 1 file changed, 15 insertions(+), 24 deletions(-) > > diff --git a/mm/shmem.c b/mm/shmem.c > index f24dfbd387ba..db7e9808830f 100644 > --- a/mm/shmem.c > +++ b/mm/shmem.c > @@ -1685,19 +1685,29 @@ static unsigned long shmem_suitable_orders(struct inode *inode, struct vm_fault > struct address_space *mapping, pgoff_t index, > unsigned long orders) > { > - struct vm_area_struct *vma = vmf->vma; > + struct vm_area_struct *vma = vmf ? vmf->vma : NULL; > unsigned long pages; > int order; > > - orders = thp_vma_suitable_orders(vma, vmf->address, orders); > - if (!orders) > - return 0; > + if (vma) { > + orders = thp_vma_suitable_orders(vma, vmf->address, orders); > + if (!orders) > + return 0; > + } > > /* Find the highest order that can add into the page cache */ > order = highest_order(orders); > while (orders) { > pages = 1UL << order; > index = round_down(index, pages); > + /* > + * Check for conflict before waiting on a huge allocation. > + * Conflict might be that a huge page has just been allocated > + * and added to page cache by a racing thread, or that there > + * is already at least one small page in the huge extent. > + * Be careful to retry when appropriate, but not forever! > + * Elsewhere -EEXIST would be the right code, but not here. > + */ > if (!xa_find(&mapping->i_pages, &index, > index + pages - 1, XA_PRESENT)) > break; > @@ -1735,7 +1745,6 @@ static struct folio *shmem_alloc_and_add_folio(struct vm_fault *vmf, > { > struct address_space *mapping = inode->i_mapping; > struct shmem_inode_info *info = SHMEM_I(inode); > - struct vm_area_struct *vma = vmf ? vmf->vma : NULL; > unsigned long suitable_orders = 0; > struct folio *folio = NULL; > long pages; > @@ -1745,26 +1754,8 @@ static struct folio *shmem_alloc_and_add_folio(struct vm_fault *vmf, > orders = 0; > > if (orders > 0) { > - if (vma && vma_is_anon_shmem(vma)) { > - suitable_orders = shmem_suitable_orders(inode, vmf, > + suitable_orders = shmem_suitable_orders(inode, vmf, > mapping, index, orders); > - } else if (orders & BIT(HPAGE_PMD_ORDER)) { > - pages = HPAGE_PMD_NR; > - suitable_orders = BIT(HPAGE_PMD_ORDER); > - index = round_down(index, HPAGE_PMD_NR); > - > - /* > - * Check for conflict before waiting on a huge allocation. > - * Conflict might be that a huge page has just been allocated > - * and added to page cache by a racing thread, or that there > - * is already at least one small page in the huge extent. > - * Be careful to retry when appropriate, but not forever! > - * Elsewhere -EEXIST would be the right code, but not here. > - */ > - if (xa_find(&mapping->i_pages, &index, > - index + HPAGE_PMD_NR - 1, XA_PRESENT)) > - return ERR_PTR(-E2BIG); > - } > > order = highest_order(suitable_orders); > while (suitable_orders) {