ceph: reduce i_nr_by_mode array size

Track usage count for individual fmode bit. This can reduce the
array size by half.

Signed-off-by: Yan, Zheng <zyan@redhat.com>

1 files changed, 31 insertions, 14 deletions

diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c
index 0a9406a8a794..a08d245f16f5 100644
--- a/fs/ceph/caps.c
+++ b/fs/ceph/caps.c
@@ -849,12 +849,14 @@ int __ceph_caps_used(struct ceph_inode_info *ci)
  */
 int __ceph_caps_file_wanted(struct ceph_inode_info *ci)
 {
-        int want = 0;
-        int mode;
-        for (mode = 0; mode < CEPH_FILE_MODE_NUM; mode++)
-                if (ci->i_nr_by_mode[mode])
-                        want |= ceph_caps_for_mode(mode);
-        return want;
+        int i, bits = 0;
+        for (i = 0; i < CEPH_FILE_MODE_BITS; i++) {
+                if (ci->i_nr_by_mode[i])
+                        bits |= 1 << i;
+        }
+        if (bits == 0)
+                return 0;
+        return ceph_caps_for_mode(bits >> 1);
 }
 
 /*
@@ -3682,6 +3684,16 @@ void ceph_flush_dirty_caps(struct ceph_mds_client *mdsc)
         dout("flush_dirty_caps done\n");
 }
 
+void __ceph_get_fmode(struct ceph_inode_info *ci, int fmode)
+{
+        int i;
+        int bits = (fmode << 1) | 1;
+        for (i = 0; i < CEPH_FILE_MODE_BITS; i++) {
+                if (bits & (1 << i))
+                        ci->i_nr_by_mode[i]++;
+        }
+}
+
 /*
  * Drop open file reference.  If we were the last open file,
  * we may need to release capabilities to the MDS (or schedule
@@ -3689,15 +3701,20 @@ void ceph_flush_dirty_caps(struct ceph_mds_client *mdsc)
  */
 void ceph_put_fmode(struct ceph_inode_info *ci, int fmode)
 {
-        struct inode *inode = &ci->vfs_inode;
-        int last = 0;
-
+        int i, last = 0;
+        int bits = (fmode << 1) | 1;
         spin_lock(&ci->i_ceph_lock);
-        dout("put_fmode %p fmode %d %d -> %d\n", inode, fmode,
-             ci->i_nr_by_mode[fmode], ci->i_nr_by_mode[fmode]-1);
-        BUG_ON(ci->i_nr_by_mode[fmode] == 0);
-        if (--ci->i_nr_by_mode[fmode] == 0)
-                last++;
+        for (i = 0; i < CEPH_FILE_MODE_BITS; i++) {
+                if (bits & (1 << i)) {
+                        BUG_ON(ci->i_nr_by_mode[i] == 0);
+                        if (--ci->i_nr_by_mode[i] == 0)
+                                last++;
+                }
+        }
+        dout("put_fmode %p fmode %d {%d,%d,%d,%d}\n",
+             &ci->vfs_inode, fmode,
+             ci->i_nr_by_mode[0], ci->i_nr_by_mode[1],
+             ci->i_nr_by_mode[2], ci->i_nr_by_mode[3]);
         spin_unlock(&ci->i_ceph_lock);
 
         if (last && ci->i_vino.snap == CEPH_NOSNAP)