| Message ID | 20220509004138.762556-8-david@fromorbit.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
| Series | XFS: LARP state machine and recovery rework | expand |
On Mon, May 09, 2022 at 10:41:27AM +1000, Dave Chinner wrote: > From: Dave Chinner <dchinner@redhat.com> > > The operations performed from XFS_DAS_FOUND_LBLK through to > XFS_DAS_RM_LBLK are now identical to XFS_DAS_FOUND_NBLK through to > XFS_DAS_RM_NBLK. We can collapse these down into a single set of > code. > > To do this, define the states that leaf and node run through as > separate sets of sequential states. Then as we move to the next > state, we can use increments rather than specific state assignments > to move through the states. This means the state progression is set > by the initial state that enters the series and we don't need to > duplicate the code anymore. > > At the exit point of the series we need to select the correct leaf > or node state, but that can also be done by state increment rather > than assignment. > > Signed-off-by: Dave Chinner <dchinner@redhat.com> > Reviewed-by: Allison Henderson<allison.henderson@oracle.com> > --- > fs/xfs/libxfs/xfs_attr.c | 127 ++++++--------------------------------- > fs/xfs/libxfs/xfs_attr.h | 9 ++- > 2 files changed, 27 insertions(+), 109 deletions(-) > > diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c > index ab8a884af512..be580da62f08 100644 > --- a/fs/xfs/libxfs/xfs_attr.c > +++ b/fs/xfs/libxfs/xfs_attr.c > @@ -394,6 +394,7 @@ xfs_attr_set_iter( > struct xfs_mount *mp = args->dp->i_mount; > > /* State machine switch */ > +next_state: > switch (attr->xattri_dela_state) { > case XFS_DAS_UNINIT: > ASSERT(0); > @@ -406,6 +407,7 @@ xfs_attr_set_iter( > return xfs_attr_node_addname(attr); > > case XFS_DAS_FOUND_LBLK: > + case XFS_DAS_FOUND_NBLK: > /* > * Find space for remote blocks and fall into the allocation > * state. > @@ -415,9 +417,10 @@ xfs_attr_set_iter( > if (error) > return error; > } > - attr->xattri_dela_state = XFS_DAS_LEAF_ALLOC_RMT; > + attr->xattri_dela_state++; > fallthrough; > case XFS_DAS_LEAF_ALLOC_RMT: > + case XFS_DAS_NODE_ALLOC_RMT: > > /* > * If there was an out-of-line value, allocate the blocks we > @@ -466,16 +469,18 @@ xfs_attr_set_iter( > return error; > /* > * Commit the flag value change and start the next trans > - * in series. > + * in series at FLIP_FLAG. > */ > - attr->xattri_dela_state = XFS_DAS_FLIP_LFLAG; > + attr->xattri_dela_state++; > trace_xfs_attr_set_iter_return(attr->xattri_dela_state, > args->dp); > return -EAGAIN; > } > > + attr->xattri_dela_state++; > fallthrough; > case XFS_DAS_FLIP_LFLAG: > + case XFS_DAS_FLIP_NFLAG: > /* > * Dismantle the "old" attribute/value pair by removing a > * "remote" value (if it exists). > @@ -485,10 +490,10 @@ xfs_attr_set_iter( > if (error) > return error; > > + attr->xattri_dela_state++; > fallthrough; > case XFS_DAS_RM_LBLK: > - /* Set state in case xfs_attr_rmtval_remove returns -EAGAIN */ > - attr->xattri_dela_state = XFS_DAS_RM_LBLK; > + case XFS_DAS_RM_NBLK: > if (args->rmtblkno) { > error = xfs_attr_rmtval_remove(attr); > if (error == -EAGAIN) > @@ -503,7 +508,16 @@ xfs_attr_set_iter( > return -EAGAIN; > } > > - fallthrough; > + /* > + * This is the end of the shared leaf/node sequence. We need > + * to continue at the next state in the sequence, but we can't > + * easily just fall through. So we increment to the next state > + * and then jump back to switch statement to evaluate the next > + * state correctly. > + */ > + attr->xattri_dela_state++; > + goto next_state; > + > case XFS_DAS_RD_LEAF: > /* > * This is the last step for leaf format. Read the block with > @@ -524,106 +538,6 @@ xfs_attr_set_iter( > > return error; > > - case XFS_DAS_FOUND_NBLK: > - /* > - * Find space for remote blocks and fall into the allocation > - * state. > - */ > - if (args->rmtblkno > 0) { > - error = xfs_attr_rmtval_find_space(attr); > - if (error) > - return error; > - } > - > - attr->xattri_dela_state = XFS_DAS_NODE_ALLOC_RMT; > - fallthrough; > - case XFS_DAS_NODE_ALLOC_RMT: > - /* > - * If there was an out-of-line value, allocate the blocks we > - * identified for its storage and copy the value. This is done > - * after we create the attribute so that we don't overflow the > - * maximum size of a transaction and/or hit a deadlock. > - */ > - if (args->rmtblkno > 0) { > - if (attr->xattri_blkcnt > 0) { > - error = xfs_attr_rmtval_set_blk(attr); > - if (error) > - return error; > - trace_xfs_attr_set_iter_return( > - attr->xattri_dela_state, args->dp); > - return -EAGAIN; > - } > - > - error = xfs_attr_rmtval_set_value(args); > - if (error) > - return error; > - } > - > - /* > - * If this was not a rename, clear the incomplete flag and we're > - * done. > - */ > - if (!(args->op_flags & XFS_DA_OP_RENAME)) { > - if (args->rmtblkno > 0) > - error = xfs_attr3_leaf_clearflag(args); > - goto out; > - } > - > - /* > - * If this is an atomic rename operation, we must "flip" the > - * incomplete flags on the "new" and "old" attribute/value pairs > - * so that one disappears and one appears atomically. Then we > - * must remove the "old" attribute/value pair. > - * > - * In a separate transaction, set the incomplete flag on the > - * "old" attr and clear the incomplete flag on the "new" attr. > - */ > - if (!xfs_has_larp(mp)) { > - error = xfs_attr3_leaf_flipflags(args); > - if (error) > - goto out; > - /* > - * Commit the flag value change and start the next trans > - * in series > - */ > - attr->xattri_dela_state = XFS_DAS_FLIP_NFLAG; > - trace_xfs_attr_set_iter_return(attr->xattri_dela_state, > - args->dp); > - return -EAGAIN; > - } > - > - fallthrough; > - case XFS_DAS_FLIP_NFLAG: > - /* > - * Dismantle the "old" attribute/value pair by removing a > - * "remote" value (if it exists). > - */ > - xfs_attr_restore_rmt_blk(args); > - > - error = xfs_attr_rmtval_invalidate(args); > - if (error) > - return error; > - > - fallthrough; > - case XFS_DAS_RM_NBLK: > - /* Set state in case xfs_attr_rmtval_remove returns -EAGAIN */ > - attr->xattri_dela_state = XFS_DAS_RM_NBLK; > - if (args->rmtblkno) { > - error = xfs_attr_rmtval_remove(attr); > - if (error == -EAGAIN) > - trace_xfs_attr_set_iter_return( > - attr->xattri_dela_state, args->dp); > - > - if (error) > - return error; > - > - attr->xattri_dela_state = XFS_DAS_CLR_FLAG; > - trace_xfs_attr_set_iter_return(attr->xattri_dela_state, > - args->dp); > - return -EAGAIN; > - } > - > - fallthrough; > case XFS_DAS_CLR_FLAG: > /* > * The last state for node format. Look up the old attr and > @@ -635,7 +549,6 @@ xfs_attr_set_iter( > ASSERT(0); > break; > } > -out: > return error; > } > > diff --git a/fs/xfs/libxfs/xfs_attr.h b/fs/xfs/libxfs/xfs_attr.h > index d016af4dbf81..37db61649217 100644 > --- a/fs/xfs/libxfs/xfs_attr.h > +++ b/fs/xfs/libxfs/xfs_attr.h > @@ -450,16 +450,21 @@ enum xfs_delattr_state { > XFS_DAS_RMTBLK, /* Removing remote blks */ > XFS_DAS_RM_NAME, /* Remove attr name */ > XFS_DAS_RM_SHRINK, /* We are shrinking the tree */ > + > + /* Leaf state set sequence */ I think this comment should note that the state increment operations of xfs_attr_set_iter requires that the exact order of the values FOUND_[LN]BLK through RM_[LN]BLK must be preserved exactly. Question: Are we supposed to be able to dela_state++ our way from RM_LBLK to RD_LEAF and from RM_NBLK to CLR_FLAG? With that comment added, Reviewed-by: Darrick J. Wong <djwong@kernel.org> --D > XFS_DAS_FOUND_LBLK, /* We found leaf blk for attr */ > XFS_DAS_LEAF_ALLOC_RMT, /* We are allocating remote blocks */ > - XFS_DAS_FOUND_NBLK, /* We found node blk for attr */ > - XFS_DAS_NODE_ALLOC_RMT, /* We are allocating remote blocks */ > XFS_DAS_FLIP_LFLAG, /* Flipped leaf INCOMPLETE attr flag */ > XFS_DAS_RM_LBLK, /* A rename is removing leaf blocks */ > XFS_DAS_RD_LEAF, /* Read in the new leaf */ > + > + /* Node state set sequence, must match leaf state above */ > + XFS_DAS_FOUND_NBLK, /* We found node blk for attr */ > + XFS_DAS_NODE_ALLOC_RMT, /* We are allocating remote blocks */ > XFS_DAS_FLIP_NFLAG, /* Flipped node INCOMPLETE attr flag */ > XFS_DAS_RM_NBLK, /* A rename is removing node blocks */ > XFS_DAS_CLR_FLAG, /* Clear incomplete flag */ > + > XFS_DAS_DONE, /* finished operation */ > }; > > -- > 2.35.1 >
On Tue, May 10, 2022 at 04:20:19PM -0700, Darrick J. Wong wrote: > On Mon, May 09, 2022 at 10:41:27AM +1000, Dave Chinner wrote: > > diff --git a/fs/xfs/libxfs/xfs_attr.h b/fs/xfs/libxfs/xfs_attr.h > > index d016af4dbf81..37db61649217 100644 > > --- a/fs/xfs/libxfs/xfs_attr.h > > +++ b/fs/xfs/libxfs/xfs_attr.h > > @@ -450,16 +450,21 @@ enum xfs_delattr_state { > > XFS_DAS_RMTBLK, /* Removing remote blks */ > > XFS_DAS_RM_NAME, /* Remove attr name */ > > XFS_DAS_RM_SHRINK, /* We are shrinking the tree */ > > + > > + /* Leaf state set sequence */ > > I think this comment should note that the state increment operations of > xfs_attr_set_iter requires that the exact order of the values > FOUND_[LN]BLK through RM_[LN]BLK must be preserved exactly. Happens later, as you've already noticed, when.... > Question: Are we supposed to be able to dela_state++ our way from > RM_LBLK to RD_LEAF and from RM_NBLK to CLR_FLAG? ... we are finally able to dela_state++ our way right through the leaf/node operations. > With that comment added, > Reviewed-by: Darrick J. Wong <djwong@kernel.org> Thanks! -Dave.
diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c index ab8a884af512..be580da62f08 100644 --- a/fs/xfs/libxfs/xfs_attr.c +++ b/fs/xfs/libxfs/xfs_attr.c @@ -394,6 +394,7 @@ xfs_attr_set_iter( struct xfs_mount *mp = args->dp->i_mount; /* State machine switch */ +next_state: switch (attr->xattri_dela_state) { case XFS_DAS_UNINIT: ASSERT(0); @@ -406,6 +407,7 @@ xfs_attr_set_iter( return xfs_attr_node_addname(attr); case XFS_DAS_FOUND_LBLK: + case XFS_DAS_FOUND_NBLK: /* * Find space for remote blocks and fall into the allocation * state. @@ -415,9 +417,10 @@ xfs_attr_set_iter( if (error) return error; } - attr->xattri_dela_state = XFS_DAS_LEAF_ALLOC_RMT; + attr->xattri_dela_state++; fallthrough; case XFS_DAS_LEAF_ALLOC_RMT: + case XFS_DAS_NODE_ALLOC_RMT: /* * If there was an out-of-line value, allocate the blocks we @@ -466,16 +469,18 @@ xfs_attr_set_iter( return error; /* * Commit the flag value change and start the next trans - * in series. + * in series at FLIP_FLAG. */ - attr->xattri_dela_state = XFS_DAS_FLIP_LFLAG; + attr->xattri_dela_state++; trace_xfs_attr_set_iter_return(attr->xattri_dela_state, args->dp); return -EAGAIN; } + attr->xattri_dela_state++; fallthrough; case XFS_DAS_FLIP_LFLAG: + case XFS_DAS_FLIP_NFLAG: /* * Dismantle the "old" attribute/value pair by removing a * "remote" value (if it exists). @@ -485,10 +490,10 @@ xfs_attr_set_iter( if (error) return error; + attr->xattri_dela_state++; fallthrough; case XFS_DAS_RM_LBLK: - /* Set state in case xfs_attr_rmtval_remove returns -EAGAIN */ - attr->xattri_dela_state = XFS_DAS_RM_LBLK; + case XFS_DAS_RM_NBLK: if (args->rmtblkno) { error = xfs_attr_rmtval_remove(attr); if (error == -EAGAIN) @@ -503,7 +508,16 @@ xfs_attr_set_iter( return -EAGAIN; } - fallthrough; + /* + * This is the end of the shared leaf/node sequence. We need + * to continue at the next state in the sequence, but we can't + * easily just fall through. So we increment to the next state + * and then jump back to switch statement to evaluate the next + * state correctly. + */ + attr->xattri_dela_state++; + goto next_state; + case XFS_DAS_RD_LEAF: /* * This is the last step for leaf format. Read the block with @@ -524,106 +538,6 @@ xfs_attr_set_iter( return error; - case XFS_DAS_FOUND_NBLK: - /* - * Find space for remote blocks and fall into the allocation - * state. - */ - if (args->rmtblkno > 0) { - error = xfs_attr_rmtval_find_space(attr); - if (error) - return error; - } - - attr->xattri_dela_state = XFS_DAS_NODE_ALLOC_RMT; - fallthrough; - case XFS_DAS_NODE_ALLOC_RMT: - /* - * If there was an out-of-line value, allocate the blocks we - * identified for its storage and copy the value. This is done - * after we create the attribute so that we don't overflow the - * maximum size of a transaction and/or hit a deadlock. - */ - if (args->rmtblkno > 0) { - if (attr->xattri_blkcnt > 0) { - error = xfs_attr_rmtval_set_blk(attr); - if (error) - return error; - trace_xfs_attr_set_iter_return( - attr->xattri_dela_state, args->dp); - return -EAGAIN; - } - - error = xfs_attr_rmtval_set_value(args); - if (error) - return error; - } - - /* - * If this was not a rename, clear the incomplete flag and we're - * done. - */ - if (!(args->op_flags & XFS_DA_OP_RENAME)) { - if (args->rmtblkno > 0) - error = xfs_attr3_leaf_clearflag(args); - goto out; - } - - /* - * If this is an atomic rename operation, we must "flip" the - * incomplete flags on the "new" and "old" attribute/value pairs - * so that one disappears and one appears atomically. Then we - * must remove the "old" attribute/value pair. - * - * In a separate transaction, set the incomplete flag on the - * "old" attr and clear the incomplete flag on the "new" attr. - */ - if (!xfs_has_larp(mp)) { - error = xfs_attr3_leaf_flipflags(args); - if (error) - goto out; - /* - * Commit the flag value change and start the next trans - * in series - */ - attr->xattri_dela_state = XFS_DAS_FLIP_NFLAG; - trace_xfs_attr_set_iter_return(attr->xattri_dela_state, - args->dp); - return -EAGAIN; - } - - fallthrough; - case XFS_DAS_FLIP_NFLAG: - /* - * Dismantle the "old" attribute/value pair by removing a - * "remote" value (if it exists). - */ - xfs_attr_restore_rmt_blk(args); - - error = xfs_attr_rmtval_invalidate(args); - if (error) - return error; - - fallthrough; - case XFS_DAS_RM_NBLK: - /* Set state in case xfs_attr_rmtval_remove returns -EAGAIN */ - attr->xattri_dela_state = XFS_DAS_RM_NBLK; - if (args->rmtblkno) { - error = xfs_attr_rmtval_remove(attr); - if (error == -EAGAIN) - trace_xfs_attr_set_iter_return( - attr->xattri_dela_state, args->dp); - - if (error) - return error; - - attr->xattri_dela_state = XFS_DAS_CLR_FLAG; - trace_xfs_attr_set_iter_return(attr->xattri_dela_state, - args->dp); - return -EAGAIN; - } - - fallthrough; case XFS_DAS_CLR_FLAG: /* * The last state for node format. Look up the old attr and @@ -635,7 +549,6 @@ xfs_attr_set_iter( ASSERT(0); break; } -out: return error; } diff --git a/fs/xfs/libxfs/xfs_attr.h b/fs/xfs/libxfs/xfs_attr.h index d016af4dbf81..37db61649217 100644 --- a/fs/xfs/libxfs/xfs_attr.h +++ b/fs/xfs/libxfs/xfs_attr.h @@ -450,16 +450,21 @@ enum xfs_delattr_state { XFS_DAS_RMTBLK, /* Removing remote blks */ XFS_DAS_RM_NAME, /* Remove attr name */ XFS_DAS_RM_SHRINK, /* We are shrinking the tree */ + + /* Leaf state set sequence */ XFS_DAS_FOUND_LBLK, /* We found leaf blk for attr */ XFS_DAS_LEAF_ALLOC_RMT, /* We are allocating remote blocks */ - XFS_DAS_FOUND_NBLK, /* We found node blk for attr */ - XFS_DAS_NODE_ALLOC_RMT, /* We are allocating remote blocks */ XFS_DAS_FLIP_LFLAG, /* Flipped leaf INCOMPLETE attr flag */ XFS_DAS_RM_LBLK, /* A rename is removing leaf blocks */ XFS_DAS_RD_LEAF, /* Read in the new leaf */ + + /* Node state set sequence, must match leaf state above */ + XFS_DAS_FOUND_NBLK, /* We found node blk for attr */ + XFS_DAS_NODE_ALLOC_RMT, /* We are allocating remote blocks */ XFS_DAS_FLIP_NFLAG, /* Flipped node INCOMPLETE attr flag */ XFS_DAS_RM_NBLK, /* A rename is removing node blocks */ XFS_DAS_CLR_FLAG, /* Clear incomplete flag */ + XFS_DAS_DONE, /* finished operation */ };