From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mout-p-103.mailbox.org (mout-p-103.mailbox.org [80.241.56.161]) (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 8C30772624; Mon, 11 Aug 2025 09:35:47 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=80.241.56.161 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754904949; cv=none; b=fxleQrLP3roFYhE3gkngIe7pI1AZJiVoRn+LttSquGixOCT4aKM9CvUa9sesTMyzQAZjFw771gVqMROgWkjmRztnJxmWf6eQpybQg9sJAnrFItBSusJ0JphSfxAVF68kb8OmgAAQXD4PhVJKdi8ImOeY77KhTeO/D3vxSJQrzzY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754904949; c=relaxed/simple; bh=fRO/XvhtmCzSop7U0WLU8SqB29CBl0HDXlMdKUkfoCk=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=L6Lq1CscblqeVRDXW4bC5MwfElylqGNREAXCBdUXzgzf/tSQZzZ5ssGXHKiF/HmLvsIJL3YUeHUBzu6/3wvXMRo7xxtHcITcXcflunHeSLFSNb4rNbi+oX3ubMKL3P9laTxNV+uoUI9yLFnwvX7ZriRaRUR51Rru+4jsqwBOdBE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=pankajraghav.com; spf=pass smtp.mailfrom=pankajraghav.com; dkim=pass (2048-bit key) header.d=pankajraghav.com header.i=@pankajraghav.com header.b=GTk5FROV; arc=none smtp.client-ip=80.241.56.161 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=pankajraghav.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=pankajraghav.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=pankajraghav.com header.i=@pankajraghav.com header.b="GTk5FROV" Received: from smtp202.mailbox.org (smtp202.mailbox.org [IPv6:2001:67c:2050:b231:465::202]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mout-p-103.mailbox.org (Postfix) with ESMTPS id 4c0qHt1TDXz9t3B; Mon, 11 Aug 2025 11:35:38 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=pankajraghav.com; s=MBO0001; t=1754904938; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=rYaSNjo652MdDtNEkrK62ubowtD18Yw4cYxTCIxPtHU=; b=GTk5FROVMTCTxXEJppTQOFY+PCoXfXU0dO6ikOewslNIUGy1NT48uxATKWrhNK5SmFUp+J bdYU+VSSFeJfM3LNhz9fz2oQVmhbI9Yxr/R9k4L8fpCJeGFyB05/RXH4ljZ+uygivdVEb6 WPyKyBkBSC2eJqSmo2xNBaUSwgfmTsvJYuJxADqsbd7JmYkDERu9VBjASWB4mxg7fL9uLp eKwwiCGqWgkU04QXht8/a4j2a7fh+CUrTGVIjQVhSevAfaixjy23fZhq9gUstYORo456H0 SNAxLMr1DEWsFAD40K3IyPE+QcXwbvAxjon0uHgBmMNsaQs9gx3Cy3fBm4tUcw== Authentication-Results: outgoing_mbo_mout; dkim=none; spf=pass (outgoing_mbo_mout: domain of kernel@pankajraghav.com designates 2001:67c:2050:b231:465::202 as permitted sender) smtp.mailfrom=kernel@pankajraghav.com Message-ID: Date: Mon, 11 Aug 2025 11:35:24 +0200 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Subject: Re: [PATCH v3 5/5] block: use largest_zero_folio in __blkdev_issue_zero_pages() To: Jens Axboe , hch@lst.de Cc: linux-kernel@vger.kernel.org, "Liam R . Howlett" , Nico Pache , Thomas Gleixner , Lorenzo Stoakes , David Hildenbrand , Michal Hocko , Dave Hansen , Mike Rapoport , Zi Yan , Vlastimil Babka , Ryan Roberts , Dev Jain , Suren Baghdasaryan , Andrew Morton , linux-mm@kvack.org, willy@infradead.org, Ritesh Harjani , linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org, "Darrick J . Wong" , mcgrof@kernel.org, gost.dev@samsung.com, Pankaj Raghav , Baolin Wang References: <20250811084113.647267-1-kernel@pankajraghav.com> <20250811084113.647267-6-kernel@pankajraghav.com> Content-Language: en-US From: Pankaj Raghav In-Reply-To: <20250811084113.647267-6-kernel@pankajraghav.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 4c0qHt1TDXz9t3B On 8/11/25 10:41, Pankaj Raghav (Samsung) wrote: > From: Pankaj Raghav > > Use largest_zero_folio() in __blkdev_issue_zero_pages(). > On systems with CONFIG_PERSISTENT_HUGE_ZERO_FOLIO enabled, we will end up > sending larger bvecs instead of multiple small ones. > > Noticed a 4% increase in performance on a commercial NVMe SSD which does > not support OP_WRITE_ZEROES. The device's MDTS was 128K. The performance > gains might be bigger if the device supports bigger MDTS. > > Acked-by: Lorenzo Stoakes > Signed-off-by: Pankaj Raghav > --- > block/blk-lib.c | 15 ++++++++------- > 1 file changed, 8 insertions(+), 7 deletions(-) > @Jens and @Christoph, is it possible to take a quick look of this patch when you have the time? I already made the changes that Christoph mentioned before, so I think it should be good to go. @Christoph, I will send the follow up patches to iomap direct io code once we get these changes merged. > diff --git a/block/blk-lib.c b/block/blk-lib.c > index 4c9f20a689f7..3030a772d3aa 100644 > --- a/block/blk-lib.c > +++ b/block/blk-lib.c > @@ -196,6 +196,8 @@ static void __blkdev_issue_zero_pages(struct block_device *bdev, > sector_t sector, sector_t nr_sects, gfp_t gfp_mask, > struct bio **biop, unsigned int flags) > { > + struct folio *zero_folio = largest_zero_folio(); > + > while (nr_sects) { > unsigned int nr_vecs = __blkdev_sectors_to_bio_pages(nr_sects); > struct bio *bio; > @@ -208,15 +210,14 @@ static void __blkdev_issue_zero_pages(struct block_device *bdev, > break; > > do { > - unsigned int len, added; > + unsigned int len; > > - len = min_t(sector_t, > - PAGE_SIZE, nr_sects << SECTOR_SHIFT); > - added = bio_add_page(bio, ZERO_PAGE(0), len, 0); > - if (added < len) > + len = min_t(sector_t, folio_size(zero_folio), > + nr_sects << SECTOR_SHIFT); > + if (!bio_add_folio(bio, zero_folio, len, 0)) > break; > - nr_sects -= added >> SECTOR_SHIFT; > - sector += added >> SECTOR_SHIFT; > + nr_sects -= len >> SECTOR_SHIFT; > + sector += len >> SECTOR_SHIFT; > } while (nr_sects); > > *biop = bio_chain_and_submit(*biop, bio); -- Pankaj