From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 1475122ACF7; Mon, 9 Jun 2025 09:27:47 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749461269; cv=none; b=RdLRcfnHAQfOvyvbGAXEcQlQW9zCwWWSXxEXiER0ihv+WlDyY1B6JDilELAjLpV/NAD9eDxIo1pi/Gfe84VCtV+pdMOTFPz8kMszHu7YHeN04FklVOuoI+pXFtADkE8oLmQcJudPuIhZ8mX7QJkJZTcbefrZqV2pUbmjncpkJ0M= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1749461269; c=relaxed/simple; bh=F+EwTiX+NdBRhK78a4yv/r21bHRaKWx+UF/pBWTsGAs=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=WUMkOMB9F/WzA8uQ6q0ZASjoMTu44vAMWLknv80eoFJMY9xYm6Zo/npQBUyf2kdy7IKW/UdrB7dSNpLDuZjlUYoR7JBkedyYNxCjwRipMK4p3sCE3BkBI9P/7JP5tCw0rMkXKH7EwXmoSmdf1FGP2rypNP5FwZUkPVDQmFGqdTo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 993D1150C; Mon, 9 Jun 2025 02:27:28 -0700 (PDT) Received: from e125769.cambridge.arm.com (e125769.cambridge.arm.com [10.1.196.27]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 399273F59E; Mon, 9 Jun 2025 02:27:45 -0700 (PDT) From: Ryan Roberts To: Andrew Morton , "Matthew Wilcox (Oracle)" , Alexander Viro , Christian Brauner , Jan Kara , David Hildenbrand , Dave Chinner , Catalin Marinas , Will Deacon , Kalesh Singh , Zi Yan Cc: Ryan Roberts , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH v5 3/5] mm/readahead: Make space in struct file_ra_state Date: Mon, 9 Jun 2025 10:27:25 +0100 Message-ID: <20250609092729.274960-4-ryan.roberts@arm.com> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20250609092729.274960-1-ryan.roberts@arm.com> References: <20250609092729.274960-1-ryan.roberts@arm.com> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit We need to be able to store the preferred folio order associated with a readahead request in the struct file_ra_state so that we can more accurately increase the order across subsequent readahead requests. But struct file_ra_state is per-struct file, so we don't really want to increase it's size. mmap_miss is currently 32 bits but it is only counted up to 10 * MMAP_LOTSAMISS, which is currently defined as 1000. So 16 bits should be plenty. Redefine it to unsigned short, making room for order as unsigned short in follow up commit. Acked-by: David Hildenbrand Reviewed-by: Jan Kara Signed-off-by: Ryan Roberts --- include/linux/fs.h | 2 +- mm/filemap.c | 11 ++++++----- 2 files changed, 7 insertions(+), 6 deletions(-) diff --git a/include/linux/fs.h b/include/linux/fs.h index 05abdabe9db7..87e7d5790e43 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1052,7 +1052,7 @@ struct file_ra_state { unsigned int size; unsigned int async_size; unsigned int ra_pages; - unsigned int mmap_miss; + unsigned short mmap_miss; loff_t prev_pos; }; diff --git a/mm/filemap.c b/mm/filemap.c index a6459874bb2a..7bb4ffca8487 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -3217,7 +3217,7 @@ static struct file *do_sync_mmap_readahead(struct vm_fault *vmf) DEFINE_READAHEAD(ractl, file, ra, mapping, vmf->pgoff); struct file *fpin = NULL; unsigned long vm_flags = vmf->vma->vm_flags; - unsigned int mmap_miss; + unsigned short mmap_miss; #ifdef CONFIG_TRANSPARENT_HUGEPAGE /* Use the readahead code, even if readahead is disabled */ @@ -3285,7 +3285,7 @@ static struct file *do_async_mmap_readahead(struct vm_fault *vmf, struct file_ra_state *ra = &file->f_ra; DEFINE_READAHEAD(ractl, file, ra, file->f_mapping, vmf->pgoff); struct file *fpin = NULL; - unsigned int mmap_miss; + unsigned short mmap_miss; /* If we don't want any read-ahead, don't bother */ if (vmf->vma->vm_flags & VM_RAND_READ || !ra->ra_pages) @@ -3605,7 +3605,7 @@ static struct folio *next_uptodate_folio(struct xa_state *xas, static vm_fault_t filemap_map_folio_range(struct vm_fault *vmf, struct folio *folio, unsigned long start, unsigned long addr, unsigned int nr_pages, - unsigned long *rss, unsigned int *mmap_miss) + unsigned long *rss, unsigned short *mmap_miss) { vm_fault_t ret = 0; struct page *page = folio_page(folio, start); @@ -3667,7 +3667,7 @@ static vm_fault_t filemap_map_folio_range(struct vm_fault *vmf, static vm_fault_t filemap_map_order0_folio(struct vm_fault *vmf, struct folio *folio, unsigned long addr, - unsigned long *rss, unsigned int *mmap_miss) + unsigned long *rss, unsigned short *mmap_miss) { vm_fault_t ret = 0; struct page *page = &folio->page; @@ -3709,7 +3709,8 @@ vm_fault_t filemap_map_pages(struct vm_fault *vmf, struct folio *folio; vm_fault_t ret = 0; unsigned long rss = 0; - unsigned int nr_pages = 0, mmap_miss = 0, mmap_miss_saved, folio_type; + unsigned int nr_pages = 0, folio_type; + unsigned short mmap_miss = 0, mmap_miss_saved; rcu_read_lock(); folio = next_uptodate_folio(&xas, mapping, end_pgoff); -- 2.43.0