| Message ID | 1482455634-9185-1-git-send-email-bo.li.liu@oracle.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
On 12/23/16 09:13, Liu Bo wrote: > Currently how btrfs dio deals with split dio write is not good > enough if dio write is split into several segments due to the > lack of contiguous space, a large dio write like 'dd bs=1G count=1' > can end up with incorrect outstanding_extents counter and endio > would complain loudly with an assertion. > > This fixes the problem by compensating the outstanding_extents > counter in inode if a large dio write gets split. Fix works. Thanks Liu bo for working on this. Tested-by: Anand Jain <anand.jain@oracle.com> > Reported-by: Anand Jain <anand.jain@oracle.com> > Signed-off-by: Liu Bo <bo.li.liu@oracle.com> > --- > fs/btrfs/inode.c | 11 +++++++++-- > 1 file changed, 9 insertions(+), 2 deletions(-) > > diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c > index a4c8796..4175987 100644 > --- a/fs/btrfs/inode.c > +++ b/fs/btrfs/inode.c > @@ -7641,11 +7641,18 @@ static void adjust_dio_outstanding_extents(struct inode *inode, > * within our reservation, otherwise we need to adjust our inode > * counter appropriately. > */ > - if (dio_data->outstanding_extents) { > + if (dio_data->outstanding_extents >= num_extents) { > dio_data->outstanding_extents -= num_extents; > } else { > + /* > + * If dio write length has been split due to no large enough > + * contiguous space, we need to compensate our inode counter > + * appropriately. > + */ > + u64 num_needed = num_extents - dio_data->outstanding_extents; > + > spin_lock(&BTRFS_I(inode)->lock); > - BTRFS_I(inode)->outstanding_extents += num_extents; > + BTRFS_I(inode)->outstanding_extents += num_needed; > spin_unlock(&BTRFS_I(inode)->lock); > } > } > -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Fri, Dec 23, 2016 at 1:13 AM, Liu Bo <bo.li.liu@oracle.com> wrote: > Currently how btrfs dio deals with split dio write is not good > enough if dio write is split into several segments due to the > lack of contiguous space, a large dio write like 'dd bs=1G count=1' > can end up with incorrect outstanding_extents counter and endio > would complain loudly with an assertion. > > This fixes the problem by compensating the outstanding_extents > counter in inode if a large dio write gets split. > > Reported-by: Anand Jain <anand.jain@oracle.com> > Signed-off-by: Liu Bo <bo.li.liu@oracle.com> Bo, can you please create a test case for fstests? Thanks > --- > fs/btrfs/inode.c | 11 +++++++++-- > 1 file changed, 9 insertions(+), 2 deletions(-) > > diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c > index a4c8796..4175987 100644 > --- a/fs/btrfs/inode.c > +++ b/fs/btrfs/inode.c > @@ -7641,11 +7641,18 @@ static void adjust_dio_outstanding_extents(struct inode *inode, > * within our reservation, otherwise we need to adjust our inode > * counter appropriately. > */ > - if (dio_data->outstanding_extents) { > + if (dio_data->outstanding_extents >= num_extents) { > dio_data->outstanding_extents -= num_extents; > } else { > + /* > + * If dio write length has been split due to no large enough > + * contiguous space, we need to compensate our inode counter > + * appropriately. > + */ > + u64 num_needed = num_extents - dio_data->outstanding_extents; > + > spin_lock(&BTRFS_I(inode)->lock); > - BTRFS_I(inode)->outstanding_extents += num_extents; > + BTRFS_I(inode)->outstanding_extents += num_needed; > spin_unlock(&BTRFS_I(inode)->lock); > } > } > -- > 2.5.5 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html
On Fri, Jan 06, 2017 at 11:28:06AM +0000, Filipe Manana wrote: > On Fri, Dec 23, 2016 at 1:13 AM, Liu Bo <bo.li.liu@oracle.com> wrote: > > Currently how btrfs dio deals with split dio write is not good > > enough if dio write is split into several segments due to the > > lack of contiguous space, a large dio write like 'dd bs=1G count=1' > > can end up with incorrect outstanding_extents counter and endio > > would complain loudly with an assertion. > > > > This fixes the problem by compensating the outstanding_extents > > counter in inode if a large dio write gets split. > > > > Reported-by: Anand Jain <anand.jain@oracle.com> > > Signed-off-by: Liu Bo <bo.li.liu@oracle.com> > > Bo, can you please create a test case for fstests? It took me some time to recall all the details, anyway, I've sent out a fstests case for it[1]. [1]: https://patchwork.kernel.org/patch/9514277/ Thanks, -liubo > > Thanks > > > --- > > fs/btrfs/inode.c | 11 +++++++++-- > > 1 file changed, 9 insertions(+), 2 deletions(-) > > > > diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c > > index a4c8796..4175987 100644 > > --- a/fs/btrfs/inode.c > > +++ b/fs/btrfs/inode.c > > @@ -7641,11 +7641,18 @@ static void adjust_dio_outstanding_extents(struct inode *inode, > > * within our reservation, otherwise we need to adjust our inode > > * counter appropriately. > > */ > > - if (dio_data->outstanding_extents) { > > + if (dio_data->outstanding_extents >= num_extents) { > > dio_data->outstanding_extents -= num_extents; > > } else { > > + /* > > + * If dio write length has been split due to no large enough > > + * contiguous space, we need to compensate our inode counter > > + * appropriately. > > + */ > > + u64 num_needed = num_extents - dio_data->outstanding_extents; > > + > > spin_lock(&BTRFS_I(inode)->lock); > > - BTRFS_I(inode)->outstanding_extents += num_extents; > > + BTRFS_I(inode)->outstanding_extents += num_needed; > > spin_unlock(&BTRFS_I(inode)->lock); > > } > > } > > -- > > 2.5.5 > > > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in > > the body of a message to majordomo@vger.kernel.org > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > > > -- > Filipe David Manana, > > "People will forget what you said, > people will forget what you did, > but people will never forget how you made them feel." -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" 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/btrfs/inode.c b/fs/btrfs/inode.c index a4c8796..4175987 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -7641,11 +7641,18 @@ static void adjust_dio_outstanding_extents(struct inode *inode, * within our reservation, otherwise we need to adjust our inode * counter appropriately. */ - if (dio_data->outstanding_extents) { + if (dio_data->outstanding_extents >= num_extents) { dio_data->outstanding_extents -= num_extents; } else { + /* + * If dio write length has been split due to no large enough + * contiguous space, we need to compensate our inode counter + * appropriately. + */ + u64 num_needed = num_extents - dio_data->outstanding_extents; + spin_lock(&BTRFS_I(inode)->lock); - BTRFS_I(inode)->outstanding_extents += num_extents; + BTRFS_I(inode)->outstanding_extents += num_needed; spin_unlock(&BTRFS_I(inode)->lock); } }
Currently how btrfs dio deals with split dio write is not good enough if dio write is split into several segments due to the lack of contiguous space, a large dio write like 'dd bs=1G count=1' can end up with incorrect outstanding_extents counter and endio would complain loudly with an assertion. This fixes the problem by compensating the outstanding_extents counter in inode if a large dio write gets split. Reported-by: Anand Jain <anand.jain@oracle.com> Signed-off-by: Liu Bo <bo.li.liu@oracle.com> --- fs/btrfs/inode.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-)