| Message ID | 20240916125707.127118-2-luca.stefani.ge1@gmail.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | btrfs: Don't block system suspend during fstrim | expand |
On Mon, Sep 16, 2024 at 02:56:14PM +0200, Luca Stefani wrote: > Per Qu Wenruo in case we have a very large disk, e.g. 8TiB device, > mostly empty although we will do the split according to our super block > locations, the last super block ends at 256G, we can submit a huge > discard for the range [256G, 8T), causing a super large delay. > > We now split the space left to discard based on BTRFS_MAX_DATA_CHUNK_SIZE > in preparation of introduction of cancellation signals handling. > > Link: https://bugzilla.kernel.org/show_bug.cgi?id=219180 > Link: https://bugzilla.suse.com/show_bug.cgi?id=1229737 > Signed-off-by: Luca Stefani <luca.stefani.ge1@gmail.com> > --- > fs/btrfs/extent-tree.c | 19 +++++++++++++++---- > 1 file changed, 15 insertions(+), 4 deletions(-) > > diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c > index a5966324607d..79b9243c9cd6 100644 > --- a/fs/btrfs/extent-tree.c > +++ b/fs/btrfs/extent-tree.c > @@ -1300,13 +1300,24 @@ static int btrfs_issue_discard(struct block_device *bdev, u64 start, u64 len, > bytes_left = end - start; > } > > - if (bytes_left) { > + while (bytes_left) { > + u64 bytes_to_discard = min(SZ_1G, bytes_left); Please define a separate constant for that and also mention it in the changelog instead of BTRFS_MAX_DATA_CHUNK_SIZE. > + > ret = blkdev_issue_discard(bdev, start >> SECTOR_SHIFT, > - bytes_left >> SECTOR_SHIFT, > + bytes_to_discard >> SECTOR_SHIFT, > GFP_NOFS); > - if (!ret) > - *discarded_bytes += bytes_left; > + > + if (ret) { > + if (ret != -EOPNOTSUPP) > + break; > + continue; > + } > + > + start += bytes_to_discard; > + bytes_left -= bytes_to_discard; > + *discarded_bytes += bytes_to_discard; > } > + > return ret; > } > > -- > 2.46.0 >
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index a5966324607d..79b9243c9cd6 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -1300,13 +1300,24 @@ static int btrfs_issue_discard(struct block_device *bdev, u64 start, u64 len, bytes_left = end - start; } - if (bytes_left) { + while (bytes_left) { + u64 bytes_to_discard = min(SZ_1G, bytes_left); + ret = blkdev_issue_discard(bdev, start >> SECTOR_SHIFT, - bytes_left >> SECTOR_SHIFT, + bytes_to_discard >> SECTOR_SHIFT, GFP_NOFS); - if (!ret) - *discarded_bytes += bytes_left; + + if (ret) { + if (ret != -EOPNOTSUPP) + break; + continue; + } + + start += bytes_to_discard; + bytes_left -= bytes_to_discard; + *discarded_bytes += bytes_to_discard; } + return ret; }
Per Qu Wenruo in case we have a very large disk, e.g. 8TiB device, mostly empty although we will do the split according to our super block locations, the last super block ends at 256G, we can submit a huge discard for the range [256G, 8T), causing a super large delay. We now split the space left to discard based on BTRFS_MAX_DATA_CHUNK_SIZE in preparation of introduction of cancellation signals handling. Link: https://bugzilla.kernel.org/show_bug.cgi?id=219180 Link: https://bugzilla.suse.com/show_bug.cgi?id=1229737 Signed-off-by: Luca Stefani <luca.stefani.ge1@gmail.com> --- fs/btrfs/extent-tree.c | 19 +++++++++++++++---- 1 file changed, 15 insertions(+), 4 deletions(-)