ext4: suppress verbose debugging information if malloc-debug is off
[pandora-kernel.git] / fs / ext4 / mballoc.c
index 851f49b..2f6f0dd 100644 (file)
@@ -342,10 +342,15 @@ static struct kmem_cache *ext4_free_ext_cachep;
 /* We create slab caches for groupinfo data structures based on the
  * superblock block size.  There will be one per mounted filesystem for
  * each unique s_blocksize_bits */
-#define NR_GRPINFO_CACHES      \
-       (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE + 1)
+#define NR_GRPINFO_CACHES 8
 static struct kmem_cache *ext4_groupinfo_caches[NR_GRPINFO_CACHES];
 
+static const char *ext4_groupinfo_slab_names[NR_GRPINFO_CACHES] = {
+       "ext4_groupinfo_1k", "ext4_groupinfo_2k", "ext4_groupinfo_4k",
+       "ext4_groupinfo_8k", "ext4_groupinfo_16k", "ext4_groupinfo_32k",
+       "ext4_groupinfo_64k", "ext4_groupinfo_128k"
+};
+
 static void ext4_mb_generate_from_pa(struct super_block *sb, void *bitmap,
                                        ext4_group_t group);
 static void ext4_mb_generate_from_freelist(struct super_block *sb, void *bitmap,
@@ -427,9 +432,10 @@ static void *mb_find_buddy(struct ext4_buddy *e4b, int order, int *max)
        }
 
        /* at order 0 we see each particular block */
-       *max = 1 << (e4b->bd_blkbits + 3);
-       if (order == 0)
+       if (order == 0) {
+               *max = 1 << (e4b->bd_blkbits + 3);
                return EXT4_MB_BITMAP(e4b);
+       }
 
        bb = EXT4_MB_BUDDY(e4b) + EXT4_SB(e4b->bd_sb)->s_mb_offsets[order];
        *max = EXT4_SB(e4b->bd_sb)->s_mb_maxs[order];
@@ -611,7 +617,6 @@ static int __mb_check_buddy(struct ext4_buddy *e4b, char *file,
        MB_CHECK_ASSERT(e4b->bd_info->bb_fragments == fragments);
 
        grp = ext4_get_group_info(sb, e4b->bd_group);
-       buddy = mb_find_buddy(e4b, 0, &max);
        list_for_each(cur, &grp->bb_prealloc_list) {
                ext4_group_t groupnr;
                struct ext4_prealloc_space *pa;
@@ -630,7 +635,12 @@ static int __mb_check_buddy(struct ext4_buddy *e4b, char *file,
 #define mb_check_buddy(e4b)
 #endif
 
-/* FIXME!! need more doc */
+/*
+ * Divide blocks started from @first with length @len into
+ * smaller chunks with power of 2 blocks.
+ * Clear the bits in bitmap which the blocks of the chunk(s) covered,
+ * then increase bb_counters[] for corresponded chunk size.
+ */
 static void ext4_mb_mark_free_simple(struct super_block *sb,
                                void *buddy, ext4_grpblk_t first, ext4_grpblk_t len,
                                        struct ext4_group_info *grp)
@@ -2414,6 +2424,55 @@ err_freesgi:
        return -ENOMEM;
 }
 
+static void ext4_groupinfo_destroy_slabs(void)
+{
+       int i;
+
+       for (i = 0; i < NR_GRPINFO_CACHES; i++) {
+               if (ext4_groupinfo_caches[i])
+                       kmem_cache_destroy(ext4_groupinfo_caches[i]);
+               ext4_groupinfo_caches[i] = NULL;
+       }
+}
+
+static int ext4_groupinfo_create_slab(size_t size)
+{
+       static DEFINE_MUTEX(ext4_grpinfo_slab_create_mutex);
+       int slab_size;
+       int blocksize_bits = order_base_2(size);
+       int cache_index = blocksize_bits - EXT4_MIN_BLOCK_LOG_SIZE;
+       struct kmem_cache *cachep;
+
+       if (cache_index >= NR_GRPINFO_CACHES)
+               return -EINVAL;
+
+       if (unlikely(cache_index < 0))
+               cache_index = 0;
+
+       mutex_lock(&ext4_grpinfo_slab_create_mutex);
+       if (ext4_groupinfo_caches[cache_index]) {
+               mutex_unlock(&ext4_grpinfo_slab_create_mutex);
+               return 0;       /* Already created */
+       }
+
+       slab_size = offsetof(struct ext4_group_info,
+                               bb_counters[blocksize_bits + 2]);
+
+       cachep = kmem_cache_create(ext4_groupinfo_slab_names[cache_index],
+                                       slab_size, 0, SLAB_RECLAIM_ACCOUNT,
+                                       NULL);
+
+       mutex_unlock(&ext4_grpinfo_slab_create_mutex);
+       if (!cachep) {
+               printk(KERN_EMERG "EXT4: no memory for groupinfo slab cache\n");
+               return -ENOMEM;
+       }
+
+       ext4_groupinfo_caches[cache_index] = cachep;
+
+       return 0;
+}
+
 int ext4_mb_init(struct super_block *sb, int needs_recovery)
 {
        struct ext4_sb_info *sbi = EXT4_SB(sb);
@@ -2421,9 +2480,6 @@ int ext4_mb_init(struct super_block *sb, int needs_recovery)
        unsigned offset;
        unsigned max;
        int ret;
-       int cache_index;
-       struct kmem_cache *cachep;
-       char *namep = NULL;
 
        i = (sb->s_blocksize_bits + 2) * sizeof(*sbi->s_mb_offsets);
 
@@ -2440,30 +2496,9 @@ int ext4_mb_init(struct super_block *sb, int needs_recovery)
                goto out;
        }
 
-       cache_index = sb->s_blocksize_bits - EXT4_MIN_BLOCK_LOG_SIZE;
-       cachep = ext4_groupinfo_caches[cache_index];
-       if (!cachep) {
-               char name[32];
-               int len = offsetof(struct ext4_group_info,
-                                       bb_counters[sb->s_blocksize_bits + 2]);
-
-               sprintf(name, "ext4_groupinfo_%d", sb->s_blocksize_bits);
-               namep = kstrdup(name, GFP_KERNEL);
-               if (!namep) {
-                       ret = -ENOMEM;
-                       goto out;
-               }
-
-               /* Need to free the kmem_cache_name() when we
-                * destroy the slab */
-               cachep = kmem_cache_create(namep, len, 0,
-                                            SLAB_RECLAIM_ACCOUNT, NULL);
-               if (!cachep) {
-                       ret = -ENOMEM;
-                       goto out;
-               }
-               ext4_groupinfo_caches[cache_index] = cachep;
-       }
+       ret = ext4_groupinfo_create_slab(sb->s_blocksize);
+       if (ret < 0)
+               goto out;
 
        /* order 0 is regular bitmap */
        sbi->s_mb_maxs[0] = sb->s_blocksize << 3;
@@ -2520,7 +2555,6 @@ out:
        if (ret) {
                kfree(sbi->s_mb_offsets);
                kfree(sbi->s_mb_maxs);
-               kfree(namep);
        }
        return ret;
 }
@@ -2734,7 +2768,6 @@ int __init ext4_init_mballoc(void)
 
 void ext4_exit_mballoc(void)
 {
-       int i;
        /*
         * Wait for completion of call_rcu()'s on ext4_pspace_cachep
         * before destroying the slab cache.
@@ -2743,15 +2776,7 @@ void ext4_exit_mballoc(void)
        kmem_cache_destroy(ext4_pspace_cachep);
        kmem_cache_destroy(ext4_ac_cachep);
        kmem_cache_destroy(ext4_free_ext_cachep);
-
-       for (i = 0; i < NR_GRPINFO_CACHES; i++) {
-               struct kmem_cache *cachep = ext4_groupinfo_caches[i];
-               if (cachep) {
-                       char *name = (char *)kmem_cache_name(cachep);
-                       kmem_cache_destroy(cachep);
-                       kfree(name);
-               }
-       }
+       ext4_groupinfo_destroy_slabs();
        ext4_remove_debugfs_entry();
 }
 
@@ -3188,7 +3213,7 @@ ext4_mb_check_group_pa(ext4_fsblk_t goal_block,
        cur_distance = abs(goal_block - cpa->pa_pstart);
        new_distance = abs(goal_block - pa->pa_pstart);
 
-       if (cur_distance < new_distance)
+       if (cur_distance <= new_distance)
                return cpa;
 
        /* drop the previous reference */
@@ -3887,7 +3912,8 @@ static void ext4_mb_show_ac(struct ext4_allocation_context *ac)
        struct super_block *sb = ac->ac_sb;
        ext4_group_t ngroups, i;
 
-       if (EXT4_SB(sb)->s_mount_flags & EXT4_MF_FS_ABORTED)
+       if (!mb_enable_debug ||
+           (EXT4_SB(sb)->s_mount_flags & EXT4_MF_FS_ABORTED))
                return;
 
        printk(KERN_ERR "EXT4-fs: Can't allocate:"
@@ -4733,7 +4759,8 @@ static int ext4_trim_extent(struct super_block *sb, int start, int count,
  * bitmap. Then issue a TRIM command on this extent and free the extent in
  * the group buddy bitmap. This is done until whole group is scanned.
  */
-ext4_grpblk_t ext4_trim_all_free(struct super_block *sb, struct ext4_buddy *e4b,
+static ext4_grpblk_t
+ext4_trim_all_free(struct super_block *sb, struct ext4_buddy *e4b,
                ext4_grpblk_t start, ext4_grpblk_t max, ext4_grpblk_t minblocks)
 {
        void *bitmap;