From patchwork Thu Feb 15 06:36:43 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 13557428 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 24C4717984; Thu, 15 Feb 2024 06:37:20 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.137.202.133 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707979041; cv=none; b=kZg+e79h0jRaTzJujxnsJpc2psKCslIOLalu62V6ytzwoxyRFhw47AarP4rKleKWCL+YZry9/Rq7xMdNJwcmm8HjQHQ2kU0qEm3jVzGgOx819XXdyBF79dUVeEeQ998LaP8zh2aT3spPwoZMNC7rAnDXcinYkrq4TQ4wPBv3+Kk= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1707979041; c=relaxed/simple; bh=RsaupyhMHGXl7MuRFwkdo+1/hRksPhSzmj1bZUxX+dg=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=dLDZ8OUIlsruRxRnRnUitWKJNwS+ir/RHePJNE6eknPBTmVQmQLejH99hIOxC5yhLpqQRLbLp8L6hdIxKZ9ubLdEV9/tvHjfnuwTph/qewseXy01orCs2XNYBmVfyA7dIiR7w1vsS3gUz/s63ndZ3q+tSJD78rX7nQhj7X3Kpas= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de; spf=none smtp.mailfrom=bombadil.srs.infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=ojz1xsKL; arc=none smtp.client-ip=198.137.202.133 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=lst.de Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="ojz1xsKL" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender :Reply-To:Content-Type:Content-ID:Content-Description; bh=E+OSD9VSpQpoZ28pgBfOHWK/m45gq5ZINg4N5qkBC0Q=; b=ojz1xsKL7yLiHr6HXkyeNSFyTs OzRaeuK4Hzu442qbSfBX+k4xEMaeju2pg+s/VA1GbW61KuexcJPAMmRVDz98mv4JU5KrmEfGKx3I6 4+exbkMiG7vHaFI4/i2IEbv2T6JBKtVN8F9jVZcwj1+d7ASZrHA3PF5hCBG+cng0XmWbe47JiLXvt LGhgnrtuaMKcpcOPKInsOMpHOK1lE261LPZK/QKFw2zE+p9c2cn9Nlm+Jnm2bF5843Cg85H6Bfeb4 8UmSpoyIKkBNE0dvO0L3HJH1d/Y67uY/hRugC1oESNSjvMTgRUDsDw8PkBdn1n1OVx1Kv02rCVBJd jEEfLK7g==; Received: from 2a02-8389-2341-5b80-39d3-4735-9a3c-88d8.cable.dynamic.v6.surfer.at ([2a02:8389:2341:5b80:39d3:4735:9a3c:88d8] helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.97.1 #2 (Red Hat Linux)) id 1raVN0-0000000F6vb-0F0x; Thu, 15 Feb 2024 06:37:18 +0000 From: Christoph Hellwig To: linux-mm@kvack.org Cc: Matthew Wilcox , Jan Kara , David Howells , Brian Foster , Christian Brauner , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, Jan Kara , Dave Chinner Subject: [PATCH 08/14] writeback: Factor writeback_get_batch() out of write_cache_pages() Date: Thu, 15 Feb 2024 07:36:43 +0100 Message-Id: <20240215063649.2164017-9-hch@lst.de> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240215063649.2164017-1-hch@lst.de> References: <20240215063649.2164017-1-hch@lst.de> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html From: "Matthew Wilcox (Oracle)" This simple helper will be the basis of the writeback iterator. To make this work, we need to remember the current index and end positions in writeback_control. Signed-off-by: Matthew Wilcox (Oracle) [hch: heavily rebased, add helpers to get the tag and end index, don't keep the end index in struct writeback_control] Signed-off-by: Christoph Hellwig Reviewed-by: Brian Foster Reviewed-by: Jan Kara Acked-by: Dave Chinner --- include/linux/writeback.h | 6 ++++ mm/page-writeback.c | 60 +++++++++++++++++++++++++-------------- 2 files changed, 44 insertions(+), 22 deletions(-) diff --git a/include/linux/writeback.h b/include/linux/writeback.h index 4b8cf9e4810bad..f67b3ea866a0fb 100644 --- a/include/linux/writeback.h +++ b/include/linux/writeback.h @@ -11,6 +11,7 @@ #include #include #include +#include struct bio; @@ -40,6 +41,7 @@ enum writeback_sync_modes { * in a manner such that unspecified fields are set to zero. */ struct writeback_control { + /* public fields that can be set and/or consumed by the caller: */ long nr_to_write; /* Write this many pages, and decrement this for each page written */ long pages_skipped; /* Pages which were not written */ @@ -77,6 +79,10 @@ struct writeback_control { */ struct swap_iocb **swap_plug; + /* internal fields used by the ->writepages implementation: */ + struct folio_batch fbatch; + pgoff_t index; + #ifdef CONFIG_CGROUP_WRITEBACK struct bdi_writeback *wb; /* wb this writeback is issued under */ struct inode *inode; /* inode being written out */ diff --git a/mm/page-writeback.c b/mm/page-writeback.c index 4bc55ce9597d13..5b8dbbef713722 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -2392,6 +2392,29 @@ static bool folio_prepare_writeback(struct address_space *mapping, return true; } +static xa_mark_t wbc_to_tag(struct writeback_control *wbc) +{ + if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages) + return PAGECACHE_TAG_TOWRITE; + return PAGECACHE_TAG_DIRTY; +} + +static pgoff_t wbc_end(struct writeback_control *wbc) +{ + if (wbc->range_cyclic) + return -1; + return wbc->range_end >> PAGE_SHIFT; +} + +static void writeback_get_batch(struct address_space *mapping, + struct writeback_control *wbc) +{ + folio_batch_release(&wbc->fbatch); + cond_resched(); + filemap_get_folios_tag(mapping, &wbc->index, wbc_end(wbc), + wbc_to_tag(wbc), &wbc->fbatch); +} + /** * write_cache_pages - walk the list of dirty pages of the given address space and write all of them. * @mapping: address space structure to write @@ -2429,38 +2452,32 @@ int write_cache_pages(struct address_space *mapping, { int ret = 0; int error; - struct folio_batch fbatch; struct folio *folio; - int nr_folios; - pgoff_t index; pgoff_t end; /* Inclusive */ - xa_mark_t tag; - folio_batch_init(&fbatch); if (wbc->range_cyclic) { - index = mapping->writeback_index; /* prev offset */ + wbc->index = mapping->writeback_index; /* prev offset */ end = -1; } else { - index = wbc->range_start >> PAGE_SHIFT; + wbc->index = wbc->range_start >> PAGE_SHIFT; end = wbc->range_end >> PAGE_SHIFT; } - if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages) { - tag_pages_for_writeback(mapping, index, end); - tag = PAGECACHE_TAG_TOWRITE; - } else { - tag = PAGECACHE_TAG_DIRTY; - } - while (index <= end) { + if (wbc->sync_mode == WB_SYNC_ALL || wbc->tagged_writepages) + tag_pages_for_writeback(mapping, wbc->index, end); + + folio_batch_init(&wbc->fbatch); + + while (wbc->index <= end) { int i; - nr_folios = filemap_get_folios_tag(mapping, &index, end, - tag, &fbatch); + writeback_get_batch(mapping, wbc); - if (nr_folios == 0) + if (wbc->fbatch.nr == 0) break; - for (i = 0; i < nr_folios; i++) { - folio = fbatch.folios[i]; + for (i = 0; i < wbc->fbatch.nr; i++) { + folio = wbc->fbatch.folios[i]; + folio_lock(folio); if (!folio_prepare_writeback(mapping, wbc, folio)) { folio_unlock(folio); @@ -2498,8 +2515,6 @@ int write_cache_pages(struct address_space *mapping, goto done; } } - folio_batch_release(&fbatch); - cond_resched(); } /* @@ -2512,6 +2527,7 @@ int write_cache_pages(struct address_space *mapping, * of the file if we are called again, which can only happen due to * -ENOMEM from the file system. */ + folio_batch_release(&wbc->fbatch); if (wbc->range_cyclic) mapping->writeback_index = 0; return ret; @@ -2519,7 +2535,7 @@ int write_cache_pages(struct address_space *mapping, done: if (wbc->range_cyclic) mapping->writeback_index = folio->index + folio_nr_pages(folio); - folio_batch_release(&fbatch); + folio_batch_release(&wbc->fbatch); return error; } EXPORT_SYMBOL(write_cache_pages);