On 2024/1/22 12:37, Gao Xiang wrote: > [你通常不会收到来自 [email protected] 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 2024/1/22 11:49, Chunhai Guo wrote: >> On 2024/1/22 10:07, Gao Xiang wrote: >>> [你通常不会收到来自 [email protected] 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/[email protected]
The result is tested with 64k sliding window change. > 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. OK. I will reply to this email when the benchmark is finished. > 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/[email protected] >>>> >>>> Suggested-by: Gao Xiang <[email protected]> >>>> Signed-off-by: Chunhai Guo <[email protected]> >>>> --- >>>> 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); >>
