On Fri, 23 Aug 2013, Gregory Farnum wrote: > Did this patch get dropped on purpose? I also don't see it in our > testing branch. We fixed d_prune to be less lame instead. That patch is waiting for Al's attention on -fsdevel. sage > -Greg > Software Engineer #42 @ http://inktank.com | http://ceph.com > > > On Sun, Aug 4, 2013 at 11:10 PM, Yan, Zheng <zheng.z.yan@xxxxxxxxx> wrote: > > From: "Yan, Zheng" <zheng.z.yan@xxxxxxxxx> > > > > The trim caps code that handles SESSION_RECALL_STATE message has > > two issues. First, it uses d_prune_aliases() to prune dentries. > > This confuses our 'dir complete' check, because d_prune_aliases() > > unhashes dentries before calling our d_prune() callback. Second, > > it only prune dentries, inodes with zero reference are still in > > the icache unless there is memory pressure. > > > > The fix is adding d_delete() and drop_inode() VFS callback. VFS > > calls our d_delete()/drop_inode() callback when a dentry/inode's > > last reference is dropped. If true is returned, VFS drop the > > dentry/inode from the cache. When handling SESSION_RECALL_STATE > > message, we mark inode with CEPH_I_TRIMCAPS flag. Our callbacks > > check the flag and session->s_trim_caps to decide if VFS should > > drop a dentry/inode. To trim an inode, we just need to reference > > dentries associated with the inode, then release them. > > > > Signed-off-by: Yan, Zheng <zheng.z.yan@xxxxxxxxx> > > --- > > fs/ceph/caps.c | 30 ++++++++++++++++++++++++++++++ > > fs/ceph/dir.c | 12 ++++++++++++ > > fs/ceph/inode.c | 11 +++++++++++ > > fs/ceph/mds_client.c | 37 ++++++++++++++++++++++++++++++------- > > fs/ceph/mds_client.h | 4 ++-- > > fs/ceph/super.c | 1 + > > fs/ceph/super.h | 3 +++ > > 7 files changed, 89 insertions(+), 9 deletions(-) > > > > diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c > > index 49590a0..332dc8d 100644 > > --- a/fs/ceph/caps.c > > +++ b/fs/ceph/caps.c > > @@ -882,6 +882,36 @@ int __ceph_caps_mds_wanted(struct ceph_inode_info *ci) > > } > > > > /* > > + * Used by ceph_d_delete()/ceph_drop_inode(). check if we should drop > > + * the inode. > > + */ > > +int ceph_trim_caps(struct ceph_inode_info *ci, int drop_inode) > > +{ > > + struct ceph_cap *cap; > > + struct rb_node *p; > > + int ret = 0; > > + > > + if (!spin_trylock(&ci->i_ceph_lock)) > > + return 0; > > + > > + if (ci->i_ceph_flags & CEPH_I_TRIMCAPS) { > > + for (p = rb_first(&ci->i_caps); p; p = rb_next(p)) { > > + cap = rb_entry(p, struct ceph_cap, ci_node); > > + if (atomic_read(&cap->session->s_trim_caps) <= 0) > > + continue; > > + if (drop_inode) > > + atomic_dec(&cap->session->s_trim_caps); > > + ret = 1; > > + } > > + if (!ret) > > + ci->i_ceph_flags &= ~CEPH_I_TRIMCAPS; > > + } > > + > > + spin_unlock(&ci->i_ceph_lock); > > + return ret; > > +} > > + > > +/* > > * called under i_ceph_lock > > */ > > static int __ceph_is_any_caps(struct ceph_inode_info *ci) > > diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c > > index 0e4da4a..9741f34 100644 > > --- a/fs/ceph/dir.c > > +++ b/fs/ceph/dir.c > > @@ -1043,6 +1043,17 @@ static int ceph_d_revalidate(struct dentry *dentry, unsigned int flags) > > return valid; > > } > > > > +static int ceph_d_delete(const struct dentry *dentry) > > +{ > > + if (dentry->d_inode) { > > + struct ceph_inode_info *ci = ceph_inode(dentry->d_inode); > > + /* need trim caps? */ > > + if (ci->i_ceph_flags & CEPH_I_TRIMCAPS) > > + return ceph_trim_caps(ci, false); > > + } > > + return 0; > > +} > > + > > /* > > * Release our ceph_dentry_info. > > */ > > @@ -1300,6 +1311,7 @@ const struct inode_operations ceph_dir_iops = { > > > > const struct dentry_operations ceph_dentry_ops = { > > .d_revalidate = ceph_d_revalidate, > > + .d_delete = ceph_d_delete, > > .d_release = ceph_d_release, > > .d_prune = ceph_d_prune, > > }; > > diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c > > index 01e4db1..371590a 100644 > > --- a/fs/ceph/inode.c > > +++ b/fs/ceph/inode.c > > @@ -431,6 +431,17 @@ void ceph_destroy_inode(struct inode *inode) > > call_rcu(&inode->i_rcu, ceph_i_callback); > > } > > > > +int ceph_drop_inode(struct inode *inode) > > +{ > > + struct ceph_inode_info *ci = ceph_inode(inode); > > + int ret = generic_drop_inode(inode); > > + > > + /* need trim caps? */ > > + if (!ret && (ci->i_ceph_flags & CEPH_I_TRIMCAPS)) > > + ret = ceph_trim_caps(ci, true); > > + > > + return ret ; > > +} > > > > /* > > * Helpers to fill in size, ctime, mtime, and atime. We have to be > > diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c > > index 2a42b5f..7c2b8d6 100644 > > --- a/fs/ceph/mds_client.c > > +++ b/fs/ceph/mds_client.c > > @@ -435,7 +435,7 @@ static struct ceph_mds_session *register_session(struct ceph_mds_client *mdsc, > > s->s_renew_seq = 0; > > INIT_LIST_HEAD(&s->s_caps); > > s->s_nr_caps = 0; > > - s->s_trim_caps = 0; > > + atomic_set(&s->s_trim_caps, 0); > > atomic_set(&s->s_ref, 1); > > INIT_LIST_HEAD(&s->s_waiting); > > INIT_LIST_HEAD(&s->s_unsafe); > > @@ -1207,9 +1207,10 @@ static int trim_caps_cb(struct inode *inode, struct ceph_cap *cap, void *arg) > > { > > struct ceph_mds_session *session = arg; > > struct ceph_inode_info *ci = ceph_inode(inode); > > + struct dentry *dentry; > > int used, oissued, mine; > > > > - if (session->s_trim_caps <= 0) > > + if (atomic_read(&session->s_trim_caps) <= 0) > > return -1; > > > > spin_lock(&ci->i_ceph_lock); > > @@ -1225,16 +1226,39 @@ static int trim_caps_cb(struct inode *inode, struct ceph_cap *cap, void *arg) > > if ((used & ~oissued) & mine) > > goto out; /* we need these caps */ > > > > - session->s_trim_caps--; > > if (oissued) { > > /* we aren't the only cap.. just remove us */ > > __queue_cap_release(session, ceph_ino(inode), cap->cap_id, > > cap->mseq, cap->issue_seq); > > __ceph_remove_cap(cap); > > + atomic_dec(&session->s_trim_caps); > > } else { > > /* try to drop referring dentries */ > > + ci->i_ceph_flags |= CEPH_I_TRIMCAPS; > > spin_unlock(&ci->i_ceph_lock); > > - d_prune_aliases(inode); > > + /* > > + * can't use d_prune_aliases(), because it unhashes dentries > > + * before calling ceph_d_prune(). > > + */ > > +restart: > > + spin_lock(&inode->i_lock); > > + hlist_for_each_entry(dentry, &inode->i_dentry, d_alias) { > > + spin_lock(&dentry->d_lock); > > + if (!dentry->d_count) { > > + dget_dlock(dentry); > > + spin_unlock(&dentry->d_lock); > > + spin_unlock(&inode->i_lock); > > + /* > > + * our d_delete callback returns true when > > + * CEPH_I_TRIMCAPS is set. This makes VFS > > + * drop the dentry. > > + */ > > + dput(dentry); > > + goto restart; > > + } > > + spin_unlock(&dentry->d_lock); > > + } > > + spin_unlock(&inode->i_lock); > > dout("trim_caps_cb %p cap %p pruned, count now %d\n", > > inode, cap, atomic_read(&inode->i_count)); > > return 0; > > @@ -1257,12 +1281,11 @@ static int trim_caps(struct ceph_mds_client *mdsc, > > dout("trim_caps mds%d start: %d / %d, trim %d\n", > > session->s_mds, session->s_nr_caps, max_caps, trim_caps); > > if (trim_caps > 0) { > > - session->s_trim_caps = trim_caps; > > + atomic_set(&session->s_trim_caps, trim_caps); > > iterate_session_caps(session, trim_caps_cb, session); > > dout("trim_caps mds%d done: %d / %d, trimmed %d\n", > > session->s_mds, session->s_nr_caps, max_caps, > > - trim_caps - session->s_trim_caps); > > - session->s_trim_caps = 0; > > + trim_caps - atomic_read(&session->s_trim_caps)); > > } > > return 0; > > } > > diff --git a/fs/ceph/mds_client.h b/fs/ceph/mds_client.h > > index c2a19fb..d0e6566 100644 > > --- a/fs/ceph/mds_client.h > > +++ b/fs/ceph/mds_client.h > > @@ -130,8 +130,8 @@ struct ceph_mds_session { > > /* protected by s_cap_lock */ > > spinlock_t s_cap_lock; > > struct list_head s_caps; /* all caps issued by this session */ > > - int s_nr_caps, s_trim_caps; > > - int s_num_cap_releases; > > + int s_nr_caps, s_num_cap_releases; > > + atomic_t s_trim_caps; > > struct list_head s_cap_releases; /* waiting cap_release messages */ > > struct list_head s_cap_releases_done; /* ready to send */ > > struct ceph_cap *s_cap_iterator; > > diff --git a/fs/ceph/super.c b/fs/ceph/super.c > > index 6627b26..bcf26bf 100644 > > --- a/fs/ceph/super.c > > +++ b/fs/ceph/super.c > > @@ -655,6 +655,7 @@ static const struct super_operations ceph_super_ops = { > > .alloc_inode = ceph_alloc_inode, > > .destroy_inode = ceph_destroy_inode, > > .write_inode = ceph_write_inode, > > + .drop_inode = ceph_drop_inode, > > .sync_fs = ceph_sync_fs, > > .put_super = ceph_put_super, > > .show_options = ceph_show_options, > > diff --git a/fs/ceph/super.h b/fs/ceph/super.h > > index e81c0b6..b87691a 100644 > > --- a/fs/ceph/super.h > > +++ b/fs/ceph/super.h > > @@ -421,6 +421,7 @@ static inline struct inode *ceph_find_inode(struct super_block *sb, > > /* > > * Ceph inode. > > */ > > +#define CEPH_I_TRIMCAPS 1 /* trim caps when possible */ > > #define CEPH_I_NODELAY 4 /* do not delay cap release */ > > #define CEPH_I_FLUSH 8 /* do not delay flush of dirty metadata */ > > #define CEPH_I_NOFLUSH 16 /* do not flush dirty caps */ > > @@ -487,6 +488,7 @@ extern int __ceph_caps_issued(struct ceph_inode_info *ci, int *implemented); > > extern int __ceph_caps_issued_mask(struct ceph_inode_info *ci, int mask, int t); > > extern int __ceph_caps_issued_other(struct ceph_inode_info *ci, > > struct ceph_cap *cap); > > +extern int ceph_trim_caps(struct ceph_inode_info *ci, int drop_inode); > > > > static inline int ceph_caps_issued(struct ceph_inode_info *ci) > > { > > @@ -675,6 +677,7 @@ extern const struct inode_operations ceph_file_iops; > > > > extern struct inode *ceph_alloc_inode(struct super_block *sb); > > extern void ceph_destroy_inode(struct inode *inode); > > +extern int ceph_drop_inode(struct inode *inode); > > > > extern struct inode *ceph_get_inode(struct super_block *sb, > > struct ceph_vino vino); > > -- > > 1.8.1.4 > > > > -- > > To unsubscribe from this list: send the line "unsubscribe ceph-devel" in > > the body of a message to majordomo@xxxxxxxxxxxxxxx > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html