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 EA0B3C47422 for ; Mon, 22 Jan 2024 02:08:09 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4TJDCD2kr4z3bqC for ; Mon, 22 Jan 2024 13:08:08 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=linux.alibaba.com (client-ip=115.124.30.101; helo=out30-101.freemail.mail.aliyun.com; envelope-from=hsiangkao@linux.alibaba.com; receiver=lists.ozlabs.org) Received: from out30-101.freemail.mail.aliyun.com (out30-101.freemail.mail.aliyun.com [115.124.30.101]) (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 4TJDC225bVz30h8 for ; Mon, 22 Jan 2024 13:07:56 +1100 (AEDT) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R551e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018045170;MF=hsiangkao@linux.alibaba.com;NM=1;PH=DS;RN=6;SR=0;TI=SMTPD_---0W.03HLg_1705889268; Received: from 30.97.48.216(mailfrom:hsiangkao@linux.alibaba.com fp:SMTPD_---0W.03HLg_1705889268) by smtp.aliyun-inc.com; Mon, 22 Jan 2024 10:07:49 +0800 Message-ID: Date: Mon, 22 Jan 2024 10:07:48 +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> From: Gao Xiang In-Reply-To: <20240120145551.1941483-1-guochunhai@vivo.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit 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 2024/1/20 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. 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);