Changeset 1eaa3cf in mainline for uspace/srv/fs/mfs/mfs_balloc.c

Timestamp:

2013-09-13T15:52:21Z (11 years ago)

Author:

Maurizio Lombardi <m.lombardi85@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

eb40d86

Parents:

b5ba8f6

Message:

mfs: cache the number of free zones to speed up subsequent requests (do not scan the whole bitmap every time statfs() is invoked).

File:

• uspace/srv/fs/mfs/mfs_balloc.c (modified) (2 diffs)

uspace/srv/fs/mfs/mfs_balloc.c

@@ -88 +88 @@
 {
         int r = mfs_alloc_bit(inst, zone, BMAP_ZONE);
+        if (r != EOK)
+                return r;
+
+        /* Update the cached number of free zones */
+        struct mfs_sb_info *sbi = inst->sbi;
+        if (sbi->nfree_zones_valid)
+                sbi->nfree_zones--;
 
         *zone += inst->sbi->firstdatazone - 1;
@@ -103 +110 @@
 mfs_free_zone(struct mfs_instance *inst, uint32_t zone)
 {
+        int r;
+
         zone -= inst->sbi->firstdatazone - 1;
 
-        return mfs_free_bit(inst, zone, BMAP_ZONE);
+        r = mfs_free_bit(inst, zone, BMAP_ZONE);
+        if (r != EOK)
+                return r;
+
+        /* Update the cached number of free zones */
+        struct mfs_sb_info *sbi = inst->sbi;
+        if (sbi->nfree_zones_valid)
+                sbi->nfree_zones++;
+
+        return r;
 }