| Message ID | 20200914093711.13523-3-nborisov@suse.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Cleanup metadata page reading path | expand |
On 2020/9/14 下午5:37, Nikolay Borisov wrote: > Metadata pages currently use __do_readpage to read metadata pages, > unfortunately this function is also used to deal with ordinary data > pages. This makes the metadata pages reading code to go through multiple > hoops in order to adhere to __do_readpage invariants. Most of these are > necessary for data pages which could be compressed. For metadata it's > enough to simply build a bio and submit it. > > To this effect simply call submit_extent_page directly from > read_extent_buffer_pages which is the only callpath used to populate > extent_buffers with data. This in turn enables further cleanups. > > Signed-off-by: Nikolay Borisov <nborisov@suse.com> Reviewed-by: Qu Wenruo <wqu@suse.com> Thanks, Qu > --- > fs/btrfs/extent_io.c | 21 ++++++++++----------- > 1 file changed, 10 insertions(+), 11 deletions(-) > > diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c > index a1e070ec7ad8..0a6cda4c30ed 100644 > --- a/fs/btrfs/extent_io.c > +++ b/fs/btrfs/extent_io.c > @@ -5573,20 +5573,19 @@ int read_extent_buffer_pages(struct extent_buffer *eb, int wait, int mirror_num) > } > > ClearPageError(page); > - err = __extent_read_full_page(page, > - btree_get_extent, &bio, > - mirror_num, &bio_flags, > - REQ_META); > + err = submit_extent_page(REQ_OP_READ | REQ_META, NULL, > + page, page_offset(page), PAGE_SIZE, 0, > + &bio, end_bio_extent_readpage, > + mirror_num, 0, 0, false); > if (err) { > - ret = err; > /* > - * We use &bio in above __extent_read_full_page, > - * so we ensure that if it returns error, the > - * current page fails to add itself to bio and > - * it's been unlocked. > - * > - * We must dec io_pages by ourselves. > + * We failed to submit the bio so it's the > + * caller's responsibility to perform cleanup > + * i.e unlock page/set error bit. > */ > + ret = err; > + SetPageError(page); > + unlock_page(page); > atomic_dec(&eb->io_pages); > } > } else { >
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index a1e070ec7ad8..0a6cda4c30ed 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -5573,20 +5573,19 @@ int read_extent_buffer_pages(struct extent_buffer *eb, int wait, int mirror_num) } ClearPageError(page); - err = __extent_read_full_page(page, - btree_get_extent, &bio, - mirror_num, &bio_flags, - REQ_META); + err = submit_extent_page(REQ_OP_READ | REQ_META, NULL, + page, page_offset(page), PAGE_SIZE, 0, + &bio, end_bio_extent_readpage, + mirror_num, 0, 0, false); if (err) { - ret = err; /* - * We use &bio in above __extent_read_full_page, - * so we ensure that if it returns error, the - * current page fails to add itself to bio and - * it's been unlocked. - * - * We must dec io_pages by ourselves. + * We failed to submit the bio so it's the + * caller's responsibility to perform cleanup + * i.e unlock page/set error bit. */ + ret = err; + SetPageError(page); + unlock_page(page); atomic_dec(&eb->io_pages); } } else {
Metadata pages currently use __do_readpage to read metadata pages, unfortunately this function is also used to deal with ordinary data pages. This makes the metadata pages reading code to go through multiple hoops in order to adhere to __do_readpage invariants. Most of these are necessary for data pages which could be compressed. For metadata it's enough to simply build a bio and submit it. To this effect simply call submit_extent_page directly from read_extent_buffer_pages which is the only callpath used to populate extent_buffers with data. This in turn enables further cleanups. Signed-off-by: Nikolay Borisov <nborisov@suse.com> --- fs/btrfs/extent_io.c | 21 ++++++++++----------- 1 file changed, 10 insertions(+), 11 deletions(-)