ceph: add caps perf metric for each superblock

Count hits and misses in the caps cache. If the client has all of
the necessary caps when a task needs references, then it's counted
as a hit. Any other situation is a miss.

URL: https://tracker.ceph.com/issues/43215
Signed-off-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

diff --git a/fs/ceph/acl.c b/fs/ceph/acl.c
index 26be652..e046574 100644 (file)
--- a/fs/ceph/acl.c
+++ b/fs/ceph/acl.c
@@ -22,7 +22,7 @@ static inline void ceph_set_cached_acl(struct inode *inode,
        struct ceph_inode_info *ci = ceph_inode(inode);
 
        spin_lock(&ci->i_ceph_lock);
-       if (__ceph_caps_issued_mask(ci, CEPH_CAP_XATTR_SHARED, 0))
+       if (__ceph_caps_issued_mask_metric(ci, CEPH_CAP_XATTR_SHARED, 0))
                set_cached_acl(inode, type, acl);
        else
                forget_cached_acl(inode, type);

diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
index f1acde6..8291486 100644 (file)
--- a/fs/ceph/caps.c
+++ b/fs/ceph/caps.c
@@ -912,6 +912,20 @@ int __ceph_caps_issued_mask(struct ceph_inode_info *ci, int mask, int touch)
        return 0;
 }
 
+int __ceph_caps_issued_mask_metric(struct ceph_inode_info *ci, int mask,
+                                  int touch)
+{
+       struct ceph_fs_client *fsc = ceph_sb_to_client(ci->vfs_inode.i_sb);
+       int r;
+
+       r = __ceph_caps_issued_mask(ci, mask, touch);
+       if (r)
+               ceph_update_cap_hit(&fsc->mdsc->metric);
+       else
+               ceph_update_cap_mis(&fsc->mdsc->metric);
+       return r;
+}
+
 /*
  * Return true if mask caps are currently being revoked by an MDS.
  */
@@ -2685,6 +2699,11 @@ out_unlock:
        if (snap_rwsem_locked)
                up_read(&mdsc->snap_rwsem);
 
+       if (!ret)
+               ceph_update_cap_mis(&mdsc->metric);
+       else if (ret == 1)
+               ceph_update_cap_hit(&mdsc->metric);
+
        dout("get_cap_refs %p ret %d got %s\n", inode,
             ret, ceph_cap_string(*got));
        return ret;

diff --git a/fs/ceph/debugfs.c b/fs/ceph/debugfs.c
index 1e7ea58..37b2775 100644 (file)
--- a/fs/ceph/debugfs.c
+++ b/fs/ceph/debugfs.c
@@ -129,6 +129,7 @@ static int metric_show(struct seq_file *s, void *p)
        struct ceph_fs_client *fsc = s->private;
        struct ceph_mds_client *mdsc = fsc->mdsc;
        struct ceph_client_metric *m = &mdsc->metric;
+       int i, nr_caps = 0;
 
        seq_printf(s, "item          total           miss            hit\n");
        seq_printf(s, "-------------------------------------------------\n");
@@ -138,6 +139,21 @@ static int metric_show(struct seq_file *s, void *p)
                   percpu_counter_sum(&m->d_lease_mis),
                   percpu_counter_sum(&m->d_lease_hit));
 
+       mutex_lock(&mdsc->mutex);
+       for (i = 0; i < mdsc->max_sessions; i++) {
+               struct ceph_mds_session *s;
+
+               s = __ceph_lookup_mds_session(mdsc, i);
+               if (!s)
+                       continue;
+               nr_caps += s->s_nr_caps;
+               ceph_put_mds_session(s);
+       }
+       mutex_unlock(&mdsc->mutex);
+       seq_printf(s, "%-14s%-16d%-16lld%lld\n", "caps", nr_caps,
+                  percpu_counter_sum(&m->i_caps_mis),
+                  percpu_counter_sum(&m->i_caps_hit));
+
        return 0;
 }
 

diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c
index 44cf851..93476d4 100644 (file)
--- a/fs/ceph/dir.c
+++ b/fs/ceph/dir.c
@@ -349,8 +349,9 @@ static int ceph_readdir(struct file *file, struct dir_context *ctx)
            !ceph_test_mount_opt(fsc, NOASYNCREADDIR) &&
            ceph_snap(inode) != CEPH_SNAPDIR &&
            __ceph_dir_is_complete_ordered(ci) &&
-           __ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1)) {
+           __ceph_caps_issued_mask_metric(ci, CEPH_CAP_FILE_SHARED, 1)) {
                int shared_gen = atomic_read(&ci->i_shared_gen);
+
                spin_unlock(&ci->i_ceph_lock);
                err = __dcache_readdir(file, ctx, shared_gen);
                if (err != -EAGAIN)
@@ -767,7 +768,7 @@ static struct dentry *ceph_lookup(struct inode *dir, struct dentry *dentry,
                    !is_root_ceph_dentry(dir, dentry) &&
                    ceph_test_mount_opt(fsc, DCACHE) &&
                    __ceph_dir_is_complete(ci) &&
-                   (__ceph_caps_issued_mask(ci, CEPH_CAP_FILE_SHARED, 1))) {
+                   __ceph_caps_issued_mask_metric(ci, CEPH_CAP_FILE_SHARED, 1)) {
                        __ceph_touch_fmode(ci, mdsc, CEPH_FILE_MODE_RD);
                        spin_unlock(&ci->i_ceph_lock);
                        dout(" dir %p complete, -ENOENT\n", dir);

diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c
index 7fef94f..357c937 100644 (file)
--- a/fs/ceph/inode.c
+++ b/fs/ceph/inode.c
@@ -2288,8 +2288,8 @@ int __ceph_do_getattr(struct inode *inode, struct page *locked_page,
 
        dout("do_getattr inode %p mask %s mode 0%o\n",
             inode, ceph_cap_string(mask), inode->i_mode);
-       if (!force && ceph_caps_issued_mask(ceph_inode(inode), mask, 1))
-               return 0;
+       if (!force && ceph_caps_issued_mask_metric(ceph_inode(inode), mask, 1))
+                       return 0;
 
        mode = (mask & CEPH_STAT_RSTAT) ? USE_AUTH_MDS : USE_ANY_MDS;
        req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_GETATTR, mode);

diff --git a/fs/ceph/metric.c b/fs/ceph/metric.c
index 873a376..2a4b739 100644 (file)
--- a/fs/ceph/metric.c
+++ b/fs/ceph/metric.c
@@ -16,13 +16,29 @@ int ceph_metric_init(struct ceph_client_metric *m)
        ret = percpu_counter_init(&m->d_lease_hit, 0, GFP_KERNEL);
        if (ret)
                return ret;
+
        ret = percpu_counter_init(&m->d_lease_mis, 0, GFP_KERNEL);
-       if (ret) {
-               percpu_counter_destroy(&m->d_lease_hit);
-               return ret;
-       }
+       if (ret)
+               goto err_d_lease_mis;
+
+       ret = percpu_counter_init(&m->i_caps_hit, 0, GFP_KERNEL);
+       if (ret)
+               goto err_i_caps_hit;
+
+       ret = percpu_counter_init(&m->i_caps_mis, 0, GFP_KERNEL);
+       if (ret)
+               goto err_i_caps_mis;
 
        return 0;
+
+err_i_caps_mis:
+       percpu_counter_destroy(&m->i_caps_hit);
+err_i_caps_hit:
+       percpu_counter_destroy(&m->d_lease_mis);
+err_d_lease_mis:
+       percpu_counter_destroy(&m->d_lease_hit);
+
+       return ret;
 }
 
 void ceph_metric_destroy(struct ceph_client_metric *m)
@@ -30,6 +46,8 @@ void ceph_metric_destroy(struct ceph_client_metric *m)
        if (!m)
                return;
 
+       percpu_counter_destroy(&m->i_caps_mis);
+       percpu_counter_destroy(&m->i_caps_hit);
        percpu_counter_destroy(&m->d_lease_mis);
        percpu_counter_destroy(&m->d_lease_hit);
 }

diff --git a/fs/ceph/metric.h b/fs/ceph/metric.h
index da725da..098ee8a 100644 (file)
--- a/fs/ceph/metric.h
+++ b/fs/ceph/metric.h
@@ -10,8 +10,21 @@ struct ceph_client_metric {
        atomic64_t            total_dentries;
        struct percpu_counter d_lease_hit;
        struct percpu_counter d_lease_mis;
+
+       struct percpu_counter i_caps_hit;
+       struct percpu_counter i_caps_mis;
 };
 
 extern int ceph_metric_init(struct ceph_client_metric *m);
 extern void ceph_metric_destroy(struct ceph_client_metric *m);
+
+static inline void ceph_update_cap_hit(struct ceph_client_metric *m)
+{
+       percpu_counter_inc(&m->i_caps_hit);
+}
+
+static inline void ceph_update_cap_mis(struct ceph_client_metric *m)
+{
+       percpu_counter_inc(&m->i_caps_mis);
+}
 #endif /* _FS_CEPH_MDS_METRIC_H */

diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index 5c73cf1..47cfd89 100644 (file)
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -645,6 +645,8 @@ static inline bool __ceph_is_any_real_caps(struct ceph_inode_info *ci)
 
 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_mask_metric(struct ceph_inode_info *ci, int mask,
+                                         int t);
 extern int __ceph_caps_issued_other(struct ceph_inode_info *ci,
                                    struct ceph_cap *cap);
 
@@ -657,12 +659,12 @@ static inline int ceph_caps_issued(struct ceph_inode_info *ci)
        return issued;
 }
 
-static inline int ceph_caps_issued_mask(struct ceph_inode_info *ci, int mask,
-                                       int touch)
+static inline int ceph_caps_issued_mask_metric(struct ceph_inode_info *ci,
+                                              int mask, int touch)
 {
        int r;
        spin_lock(&ci->i_ceph_lock);
-       r = __ceph_caps_issued_mask(ci, mask, touch);
+       r = __ceph_caps_issued_mask_metric(ci, mask, touch);
        spin_unlock(&ci->i_ceph_lock);
        return r;
 }

diff --git a/fs/ceph/xattr.c b/fs/ceph/xattr.c
index 7b8a070..71ee34d 100644 (file)
--- a/fs/ceph/xattr.c
+++ b/fs/ceph/xattr.c
@@ -856,7 +856,7 @@ ssize_t __ceph_getxattr(struct inode *inode, const char *name, void *value,
 
        if (ci->i_xattrs.version == 0 ||
            !((req_mask & CEPH_CAP_XATTR_SHARED) ||
-             __ceph_caps_issued_mask(ci, CEPH_CAP_XATTR_SHARED, 1))) {
+             __ceph_caps_issued_mask_metric(ci, CEPH_CAP_XATTR_SHARED, 1))) {
                spin_unlock(&ci->i_ceph_lock);
 
                /* security module gets xattr while filling trace */
@@ -914,7 +914,7 @@ ssize_t ceph_listxattr(struct dentry *dentry, char *names, size_t size)
             ci->i_xattrs.version, ci->i_xattrs.index_version);
 
        if (ci->i_xattrs.version == 0 ||
-           !__ceph_caps_issued_mask(ci, CEPH_CAP_XATTR_SHARED, 1)) {
+           !__ceph_caps_issued_mask_metric(ci, CEPH_CAP_XATTR_SHARED, 1)) {
                spin_unlock(&ci->i_ceph_lock);
                err = ceph_do_getattr(inode, CEPH_STAT_CAP_XATTR, true);
                if (err)