| Message ID | 1309398299-9988-1-git-send-email-tytso@mit.edu |
|---|---|
| State | Accepted, archived |
| Headers | show |
Hi Ted, 2011/6/30 Theodore Ts'o <tytso@mit.edu>: > These days, bio_alloc() is guaranteed to never fail (as long as nvecs > is less than BIO_MAX_PAGES), so we don't need the loop around the > struct bio allocation. > > Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> > --- > fs/ext4/page-io.c | 6 +----- > 1 files changed, 1 insertions(+), 5 deletions(-) > > diff --git a/fs/ext4/page-io.c b/fs/ext4/page-io.c > index 7bb8f76..430c401 100644 > --- a/fs/ext4/page-io.c > +++ b/fs/ext4/page-io.c > @@ -285,11 +285,7 @@ static int io_submit_init(struct ext4_io_submit *io, > io_end = ext4_init_io_end(inode, GFP_NOFS); > if (!io_end) > return -ENOMEM; > - do { > - bio = bio_alloc(GFP_NOIO, nvecs); > - nvecs >>= 1; > - } while (bio == NULL); > - > + bio = bio_alloc(GFP_NOIO, min(nvecs, BIO_MAX_PAGES)); Is this needn't to check if bio_alloc success? > bio->bi_sector = bh->b_blocknr * (bh->b_size >> 9); > bio->bi_bdev = bh->b_bdev; > bio->bi_private = io->io_end = io_end; > -- > 1.7.4.1.22.gec8e1.dirty > > -- Asked-by: LiuQi <lingjiujianke@gmail.com> -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
2011/6/30 Theodore Ts'o <tytso@mit.edu>: > These days, bio_alloc() is guaranteed to never fail (as long as nvecs > is less than BIO_MAX_PAGES), so we don't need the loop around the > struct bio allocation. > > Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> > --- > fs/ext4/page-io.c | 6 +----- > 1 files changed, 1 insertions(+), 5 deletions(-) > > diff --git a/fs/ext4/page-io.c b/fs/ext4/page-io.c > index 7bb8f76..430c401 100644 > --- a/fs/ext4/page-io.c > +++ b/fs/ext4/page-io.c > @@ -285,11 +285,7 @@ static int io_submit_init(struct ext4_io_submit *io, > io_end = ext4_init_io_end(inode, GFP_NOFS); > if (!io_end) > return -ENOMEM; > - do { > - bio = bio_alloc(GFP_NOIO, nvecs); > - nvecs >>= 1; > - } while (bio == NULL); > - > + bio = bio_alloc(GFP_NOIO, min(nvecs, BIO_MAX_PAGES)); I think , If this do not need to loop around the struct bio allocation insurance, if it check allocation value and give the faild message, maybe better. is it? > bio->bi_sector = bh->b_blocknr * (bh->b_size >> 9); > bio->bi_bdev = bh->b_bdev; > bio->bi_private = io->io_end = io_end; > -- > 1.7.4.1.22.gec8e1.dirty > > -- > To unsubscribe from this list: send the line "unsubscribe linux-ext4" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Thu, Jun 30, 2011 at 10:12:25AM +0800, Steven Liu wrote: > > + bio = bio_alloc(GFP_NOIO, min(nvecs, BIO_MAX_PAGES)); > Is this needn't to check if bio_alloc success? No, that was the point of this patch. See the commit description. Also see the comment for bio_alloc() in fs/bio.c, and note that the __GFP_WAIT bit is set in GFP_NOFS. Regards, - Ted -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/fs/ext4/page-io.c b/fs/ext4/page-io.c index 7bb8f76..430c401 100644 --- a/fs/ext4/page-io.c +++ b/fs/ext4/page-io.c @@ -285,11 +285,7 @@ static int io_submit_init(struct ext4_io_submit *io, io_end = ext4_init_io_end(inode, GFP_NOFS); if (!io_end) return -ENOMEM; - do { - bio = bio_alloc(GFP_NOIO, nvecs); - nvecs >>= 1; - } while (bio == NULL); - + bio = bio_alloc(GFP_NOIO, min(nvecs, BIO_MAX_PAGES)); bio->bi_sector = bh->b_blocknr * (bh->b_size >> 9); bio->bi_bdev = bh->b_bdev; bio->bi_private = io->io_end = io_end;
These days, bio_alloc() is guaranteed to never fail (as long as nvecs is less than BIO_MAX_PAGES), so we don't need the loop around the struct bio allocation. Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> --- fs/ext4/page-io.c | 6 +----- 1 files changed, 1 insertions(+), 5 deletions(-)