On Mon, 17 Apr 2023 15:00:25 +0800 Gao Xiang <[email protected]> wrote:
> On 2023/4/17 14:52, Gao Xiang wrote: > > > > > > On 2023/4/17 14:41, Yue Hu wrote: > >> From: Yue Hu <[email protected]> > >> > >> The icur field is only used in z_erofs_try_inplace_io(). Let's just use > >> a local variable instead. And no need to check if the pcluster is inline > >> when setting icur since inline page cannot be used for inplace I/O. > > Where do we check if the pcluster is inline? /* since file-backed online pages are traversed in reverse order */ fe->icur = z_erofs_pclusterpages(fe->pcl); static inline unsigned int z_erofs_pclusterpages(struct z_erofs_pcluster *pcl) { if (z_erofs_is_inline_pcluster(pcl)) return 1; [...] > > >> > >> Signed-off-by: Yue Hu <[email protected]> > > > > Nope, it's a behavior change. > > Other users could feed more inplace I/O pages before I/O submission > > to reduce memory consumption, it's common when applying stress model > > in low memory scenarios. > > Oh, I misread it. I think it can be done in this way although > each following users will now rescan the whole array all the time. > > Reviewed-by: Gao Xiang <[email protected]> > > > > > Thanks, > > Gao Xiang > > > >> --- > >> ?0?2 fs/erofs/zdata.c | 13 +++++-------- > >> ?0?2 1 file changed, 5 insertions(+), 8 deletions(-) > >> > >> diff --git a/fs/erofs/zdata.c b/fs/erofs/zdata.c > >> index f759152feffa..f8bf2b227942 100644 > >> --- a/fs/erofs/zdata.c > >> +++ b/fs/erofs/zdata.c > >> @@ -554,9 +554,6 @@ struct z_erofs_decompress_frontend { > >> ?0?2?0?2?0?2?0?2?0?2 /* used for applying cache strategy on the fly */ > >> ?0?2?0?2?0?2?0?2?0?2 bool backmost; > >> ?0?2?0?2?0?2?0?2?0?2 erofs_off_t headoffset; > >> - > >> -?0?2?0?2?0?2 /* a pointer used to pick up inplace I/O pages */ > >> -?0?2?0?2?0?2 unsigned int icur; > >> ?0?2 }; > >> ?0?2 #define DECOMPRESS_FRONTEND_INIT(__i) { \ > >> @@ -707,11 +704,13 @@ static bool z_erofs_try_inplace_io(struct > >> z_erofs_decompress_frontend *fe, > >> ?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2 > >> struct z_erofs_bvec *bvec) > >> ?0?2 { > >> ?0?2?0?2?0?2?0?2?0?2 struct z_erofs_pcluster *const pcl = fe->pcl; > >> +?0?2?0?2?0?2 /* file-backed online pages are traversed in reverse order > >> */ > > Although please help refine the comment below: > > /* scan & fill inplace I/O pages in the reverse order */ Ok, will refine it in v2. > > Thanks, > Gao Xiang > > >> +?0?2?0?2?0?2 unsigned int icur = pcl->pclusterpages; > >> -?0?2?0?2?0?2 while (fe->icur > 0) { > >> -?0?2?0?2?0?2?0?2?0?2?0?2?0?2 if > >> (!cmpxchg(&pcl->compressed_bvecs[--fe->icur].page, > >> +?0?2?0?2?0?2 while (icur > 0) { > >> +?0?2?0?2?0?2?0?2?0?2?0?2?0?2 if > >> (!cmpxchg(&pcl->compressed_bvecs[--icur].page, > >> ?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2 > >> NULL, bvec->page)) { > >> -?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2 > >> pcl->compressed_bvecs[fe->icur] = *bvec; > >> +?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2 pcl->compressed_bvecs[icur] > >> = *bvec; > >> ?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2 return true; > >> ?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2 } > >> ?0?2?0?2?0?2?0?2?0?2 } > >> @@ -877,8 +876,6 @@ static int z_erofs_collector_begin(struct > >> z_erofs_decompress_frontend *fe) > >> ?0?2?0?2?0?2?0?2?0?2 } > >> ?0?2?0?2?0?2?0?2?0?2 z_erofs_bvec_iter_begin(&fe->biter, &fe->pcl->bvset, > >> ?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2?0?2 > >> Z_EROFS_INLINE_BVECS, fe->pcl->vcnt); > >> -?0?2?0?2?0?2 /* since file-backed online pages are traversed in reverse > >> order */ > >> -?0?2?0?2?0?2 fe->icur = z_erofs_pclusterpages(fe->pcl); > >> ?0?2?0?2?0?2?0?2?0?2 return 0; > >> ?0?2 }
