From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id C2DDCC4725D for ; Mon, 22 Jan 2024 04:37:17 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4TJHWJ01JJz3brc for ; Mon, 22 Jan 2024 15:37:16 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=linux.alibaba.com (client-ip=115.124.30.119; helo=out30-119.freemail.mail.aliyun.com; envelope-from=hsiangkao@linux.alibaba.com; receiver=lists.ozlabs.org) Received: from out30-119.freemail.mail.aliyun.com (out30-119.freemail.mail.aliyun.com [115.124.30.119]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4TJHWD1j6Rz309c for ; Mon, 22 Jan 2024 15:37:10 +1100 (AEDT) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R971e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018046060;MF=hsiangkao@linux.alibaba.com;NM=1;PH=DS;RN=6;SR=0;TI=SMTPD_---0W.0cDwF_1705898222; Received: from 30.97.48.216(mailfrom:hsiangkao@linux.alibaba.com fp:SMTPD_---0W.0cDwF_1705898222) by smtp.aliyun-inc.com; Mon, 22 Jan 2024 12:37:03 +0800 Message-ID: Date: Mon, 22 Jan 2024 12:37:01 +0800 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2] erofs: relaxed temporary buffers allocation on readahead To: Chunhai Guo , "xiang@kernel.org" References: <20240120145551.1941483-1-guochunhai@vivo.com> <0aae43b2-c37b-41c8-be3f-3ebf0bb3d052@vivo.com> From: Gao Xiang In-Reply-To: <0aae43b2-c37b-41c8-be3f-3ebf0bb3d052@vivo.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-BeenThere: linux-erofs@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Development of Linux EROFS file system List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: "linux-erofs@lists.ozlabs.org" , "huyue2@coolpad.com" Errors-To: linux-erofs-bounces+linux-erofs=archiver.kernel.org@lists.ozlabs.org Sender: "Linux-erofs" On 2024/1/22 11:49, Chunhai Guo wrote: > On 2024/1/22 10:07, Gao Xiang wrote: >> [你通常不会收到来自 hsiangkao@linux.alibaba.com 的电子邮件。请访问 https://aka.ms/LearnAboutSenderIdentification，以了解这一点为什么很重要] >> >> On 2024/1/20 22:55, Chunhai Guo wrote: >>> Even with inplace decompression, sometimes extra temporary buffers are >>> still needed for decompression. In low-memory scenarios, it would be >>> better to try to allocate with GFP_NOWAIT on readahead first. That can >>> help reduce the time spent on page allocation under memory pressure. >>> >>> There is an average reduction of 21% in page allocation time under >> It would be better to add a table to show the absolute numbers too >> (like what you did in the global pool commit.) If it's possible, there >> is no need to send a update version for this, just reply the updated >> commit message and I will update the commit manually. > > > The table below shows detailed numbers. The reduction I mentioned before > was not accurate enough. Please help correct the improvement from 21% to > 20.21%. > > > +--------------+----------------+---------------+---------+ > | | w/o GFP_NOWAIT | w/ GFP_NOWAIT | diff | > +--------------+----------------+---------------+---------+ > | Average (ms) | 3364 | 2684 | -20.21% | > +--------------+----------------+---------------+---------+ Did it test without the 16k sliding window change? https://lore.kernel.org/linux-erofs/69711d55-f7a2-420b-9ba8-fa2921f66a4c@vivo.com Could you benchmark these two optimizations together to show the extreme optimized case without a global pool? With a new table if possible? I will add this to the commit message too. Thanks, Gao Xiang > > Thanks, > > >> >> Otherwise it looks good to me, >> >> Thanks, >> Gao Xiang >> >>> multi-app launch benchmark workload [1] on ARM64 Android devices running >>> the 5.15 kernel with an 8-core CPU and 8GB of memory. >>> >>> [1] https://lore.kernel.org/r/20240109074143.4138783-1-guochunhai@vivo.com >>> >>> Suggested-by: Gao Xiang >>> Signed-off-by: Chunhai Guo >>> --- >>> fs/erofs/compress.h | 5 ++--- >>> fs/erofs/decompressor.c | 5 +++-- >>> fs/erofs/decompressor_deflate.c | 19 +++++++++++++------ >>> fs/erofs/decompressor_lzma.c | 17 ++++++++++++----- >>> fs/erofs/zdata.c | 16 ++++++++++++---- >>> 5 files changed, 42 insertions(+), 20 deletions(-) >>> >>> diff --git a/fs/erofs/compress.h b/fs/erofs/compress.h >>> index 279933e007d2..7cc5841577b2 100644 >>> --- a/fs/erofs/compress.h >>> +++ b/fs/erofs/compress.h >>> @@ -11,13 +11,12 @@ >>> struct z_erofs_decompress_req { >>> struct super_block *sb; >>> struct page **in, **out; >>> - >>> unsigned short pageofs_in, pageofs_out; >>> unsigned int inputsize, outputsize; >>> >>> - /* indicate the algorithm will be used for decompression */ >>> - unsigned int alg; >>> + unsigned int alg; /* the algorithm for decompression */ >>> bool inplace_io, partial_decoding, fillgaps; >>> + gfp_t gfp; /* allocation flags for extra temporary buffers */ >>> }; >>> >>> struct z_erofs_decompressor { >>> diff --git a/fs/erofs/decompressor.c b/fs/erofs/decompressor.c >>> index 1d65b9f60a39..ef2b08ec9830 100644 >>> --- a/fs/erofs/decompressor.c >>> +++ b/fs/erofs/decompressor.c >>> @@ -111,8 +111,9 @@ static int z_erofs_lz4_prepare_dstpages(struct z_erofs_lz4_decompress_ctx *ctx, >>> victim = availables[--top]; >>> get_page(victim); >>> } else { >>> - victim = erofs_allocpage(pagepool, >>> - GFP_KERNEL | __GFP_NOFAIL); >>> + victim = erofs_allocpage(pagepool, rq->gfp); >>> + if (!victim) >>> + return -ENOMEM; >>> set_page_private(victim, Z_EROFS_SHORTLIVED_PAGE); >>> } >>> rq->out[i] = victim; >>> diff --git a/fs/erofs/decompressor_deflate.c b/fs/erofs/decompressor_deflate.c >>> index 4a64a9c91dd3..b98872058abe 100644 >>> --- a/fs/erofs/decompressor_deflate.c >>> +++ b/fs/erofs/decompressor_deflate.c >>> @@ -95,7 +95,7 @@ int z_erofs_load_deflate_config(struct super_block *sb, >>> } >>> >>> int z_erofs_deflate_decompress(struct z_erofs_decompress_req *rq, >>> - struct page **pagepool) >>> + struct page **pgpl) >>> { >>> const unsigned int nrpages_out = >>> PAGE_ALIGN(rq->pageofs_out + rq->outputsize) >> PAGE_SHIFT; >>> @@ -158,8 +158,12 @@ int z_erofs_deflate_decompress(struct z_erofs_decompress_req *rq, >>> strm->z.avail_out = min_t(u32, outsz, PAGE_SIZE - pofs); >>> outsz -= strm->z.avail_out; >>> if (!rq->out[no]) { >>> - rq->out[no] = erofs_allocpage(pagepool, >>> - GFP_KERNEL | __GFP_NOFAIL); >>> + rq->out[no] = erofs_allocpage(pgpl, rq->gfp); >>> + if (!rq->out[no]) { >>> + kout = NULL; >>> + err = -ENOMEM; >>> + break; >>> + } >>> set_page_private(rq->out[no], >>> Z_EROFS_SHORTLIVED_PAGE); >>> } >>> @@ -211,8 +215,11 @@ int z_erofs_deflate_decompress(struct z_erofs_decompress_req *rq, >>> >>> DBG_BUGON(erofs_page_is_managed(EROFS_SB(sb), >>> rq->in[j])); >>> - tmppage = erofs_allocpage(pagepool, >>> - GFP_KERNEL | __GFP_NOFAIL); >>> + tmppage = erofs_allocpage(pgpl, rq->gfp); >>> + if (!tmppage) { >>> + err = -ENOMEM; >>> + goto failed; >>> + } >>> set_page_private(tmppage, Z_EROFS_SHORTLIVED_PAGE); >>> copy_highpage(tmppage, rq->in[j]); >>> rq->in[j] = tmppage; >>> @@ -230,7 +237,7 @@ int z_erofs_deflate_decompress(struct z_erofs_decompress_req *rq, >>> break; >>> } >>> } >>> - >>> +failed: >>> if (zlib_inflateEnd(&strm->z) != Z_OK && !err) >>> err = -EIO; >>> if (kout) >>> diff --git a/fs/erofs/decompressor_lzma.c b/fs/erofs/decompressor_lzma.c >>> index 2dd14f99c1dc..6ca357d83cfa 100644 >>> --- a/fs/erofs/decompressor_lzma.c >>> +++ b/fs/erofs/decompressor_lzma.c >>> @@ -148,7 +148,7 @@ int z_erofs_load_lzma_config(struct super_block *sb, >>> } >>> >>> int z_erofs_lzma_decompress(struct z_erofs_decompress_req *rq, >>> - struct page **pagepool) >>> + struct page **pgpl) >>> { >>> const unsigned int nrpages_out = >>> PAGE_ALIGN(rq->pageofs_out + rq->outputsize) >> PAGE_SHIFT; >>> @@ -215,8 +215,11 @@ int z_erofs_lzma_decompress(struct z_erofs_decompress_req *rq, >>> PAGE_SIZE - pageofs); >>> outlen -= strm->buf.out_size; >>> if (!rq->out[no] && rq->fillgaps) { /* deduped */ >>> - rq->out[no] = erofs_allocpage(pagepool, >>> - GFP_KERNEL | __GFP_NOFAIL); >>> + rq->out[no] = erofs_allocpage(pgpl, rq->gfp); >>> + if (!rq->out[no]) { >>> + err = -ENOMEM; >>> + break; >>> + } >>> set_page_private(rq->out[no], >>> Z_EROFS_SHORTLIVED_PAGE); >>> } >>> @@ -258,8 +261,11 @@ int z_erofs_lzma_decompress(struct z_erofs_decompress_req *rq, >>> >>> DBG_BUGON(erofs_page_is_managed(EROFS_SB(rq->sb), >>> rq->in[j])); >>> - tmppage = erofs_allocpage(pagepool, >>> - GFP_KERNEL | __GFP_NOFAIL); >>> + tmppage = erofs_allocpage(pgpl, rq->gfp); >>> + if (!tmppage) { >>> + err = -ENOMEM; >>> + goto failed; >>> + } >>> set_page_private(tmppage, Z_EROFS_SHORTLIVED_PAGE); >>> copy_highpage(tmppage, rq->in[j]); >>> rq->in[j] = tmppage; >>> @@ -277,6 +283,7 @@ int z_erofs_lzma_decompress(struct z_erofs_decompress_req *rq, >>> break; >>> } >>> } >>> +failed: >>> if (no < nrpages_out && strm->buf.out) >>> kunmap(rq->out[no]); >>> if (ni < nrpages_in) >>> diff --git a/fs/erofs/zdata.c b/fs/erofs/zdata.c >>> index 692c0c39be63..a293de2a60ed 100644 >>> --- a/fs/erofs/zdata.c >>> +++ b/fs/erofs/zdata.c >>> @@ -82,6 +82,9 @@ struct z_erofs_pcluster { >>> /* L: indicate several pageofs_outs or not */ >>> bool multibases; >>> >>> + /* L: whether extra buffer allocations are best-effort */ >>> + bool besteffort; >>> + >>> /* A: compressed bvecs (can be cached or inplaced pages) */ >>> struct z_erofs_bvec compressed_bvecs[]; >>> }; >>> @@ -964,7 +967,7 @@ static int z_erofs_read_fragment(struct super_block *sb, struct page *page, >>> } >>> >>> static int z_erofs_do_read_page(struct z_erofs_decompress_frontend *fe, >>> - struct page *page) >>> + struct page *page, bool ra) >>> { >>> struct inode *const inode = fe->inode; >>> struct erofs_map_blocks *const map = &fe->map; >>> @@ -1014,6 +1017,7 @@ static int z_erofs_do_read_page(struct z_erofs_decompress_frontend *fe, >>> err = z_erofs_pcluster_begin(fe); >>> if (err) >>> goto out; >>> + fe->pcl->besteffort |= !ra; >>> } >>> >>> /* >>> @@ -1280,7 +1284,11 @@ static int z_erofs_decompress_pcluster(struct z_erofs_decompress_backend *be, >>> .inplace_io = overlapped, >>> .partial_decoding = pcl->partial, >>> .fillgaps = pcl->multibases, >>> + .gfp = pcl->besteffort ? >>> + GFP_KERNEL | __GFP_NOFAIL : >>> + GFP_NOWAIT | __GFP_NORETRY >>> }, be->pagepool); >>> + pcl->besteffort = false; >>> >>> /* must handle all compressed pages before actual file pages */ >>> if (z_erofs_is_inline_pcluster(pcl)) { >>> @@ -1785,7 +1793,7 @@ static void z_erofs_pcluster_readmore(struct z_erofs_decompress_frontend *f, >>> if (PageUptodate(page)) >>> unlock_page(page); >>> else >>> - (void)z_erofs_do_read_page(f, page); >>> + (void)z_erofs_do_read_page(f, page, !!rac); >>> put_page(page); >>> } >>> >>> @@ -1806,7 +1814,7 @@ static int z_erofs_read_folio(struct file *file, struct folio *folio) >>> f.headoffset = (erofs_off_t)folio->index << PAGE_SHIFT; >>> >>> z_erofs_pcluster_readmore(&f, NULL, true); >>> - err = z_erofs_do_read_page(&f, &folio->page); >>> + err = z_erofs_do_read_page(&f, &folio->page, false); >>> z_erofs_pcluster_readmore(&f, NULL, false); >>> z_erofs_pcluster_end(&f); >>> >>> @@ -1847,7 +1855,7 @@ static void z_erofs_readahead(struct readahead_control *rac) >>> folio = head; >>> head = folio_get_private(folio); >>> >>> - err = z_erofs_do_read_page(&f, &folio->page); >>> + err = z_erofs_do_read_page(&f, &folio->page, true); >>> if (err && err != -EINTR) >>> erofs_err(inode->i_sb, "readahead error at folio %lu @ nid %llu", >>> folio->index, EROFS_I(inode)->nid); > >