From 6ba495e9259cd9a0b40ebd6c315143535c92542f Mon Sep 17 00:00:00 2001 From: Theodore Ts'o Date: Fri, 18 Sep 2009 13:38:55 -0400 Subject: [PATCH] ext4: Add configurable run-time mballoc debugging Allow mballoc debugging to be enabled at run-time instead of just at compile time. Signed-off-by: "Theodore Ts'o" --- fs/ext4/Kconfig | 9 ++++++ fs/ext4/mballoc.c | 81 ++++++++++++++++++++++++++++++++++------------- fs/ext4/mballoc.h | 16 +++++++--- 3 files changed, 80 insertions(+), 26 deletions(-) diff --git a/fs/ext4/Kconfig b/fs/ext4/Kconfig index 152304624644..d5c0ea2e8f2d 100644 --- a/fs/ext4/Kconfig +++ b/fs/ext4/Kconfig @@ -77,3 +77,12 @@ config EXT4_FS_SECURITY If you are not using a security module that requires using extended attributes for file security labels, say N. + +config EXT4_DEBUG + bool "EXT4 debugging support" + depends on EXT4_FS + help + Enables run-time debugging support for the ext4 filesystem. + + If you select Y here, then you will be able to turn on debugging + with a command such as "echo 1 > /sys/kernel/debug/ext4/mballoc-debug" diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c index 68cde598b3bf..d80b300c1779 100644 --- a/fs/ext4/mballoc.c +++ b/fs/ext4/mballoc.c @@ -22,6 +22,7 @@ */ #include "mballoc.h" +#include #include /* @@ -743,7 +744,7 @@ static int ext4_mb_init_cache(struct page *page, char *incore) char *data; char *bitmap; - mb_debug("init page %lu\n", page->index); + mb_debug(1, "init page %lu\n", page->index); inode = page->mapping->host; sb = inode->i_sb; @@ -822,7 +823,7 @@ static int ext4_mb_init_cache(struct page *page, char *incore) set_bitmap_uptodate(bh[i]); bh[i]->b_end_io = end_buffer_read_sync; submit_bh(READ, bh[i]); - mb_debug("read bitmap for group %u\n", first_group + i); + mb_debug(1, "read bitmap for group %u\n", first_group + i); } /* wait for I/O completion */ @@ -862,7 +863,7 @@ static int ext4_mb_init_cache(struct page *page, char *incore) if ((first_block + i) & 1) { /* this is block of buddy */ BUG_ON(incore == NULL); - mb_debug("put buddy for group %u in page %lu/%x\n", + mb_debug(1, "put buddy for group %u in page %lu/%x\n", group, page->index, i * blocksize); grinfo = ext4_get_group_info(sb, group); grinfo->bb_fragments = 0; @@ -878,7 +879,7 @@ static int ext4_mb_init_cache(struct page *page, char *incore) } else { /* this is block of bitmap */ BUG_ON(incore != NULL); - mb_debug("put bitmap for group %u in page %lu/%x\n", + mb_debug(1, "put bitmap for group %u in page %lu/%x\n", group, page->index, i * blocksize); /* see comments in ext4_mb_put_pa() */ @@ -922,7 +923,7 @@ ext4_mb_load_buddy(struct super_block *sb, ext4_group_t group, struct ext4_sb_info *sbi = EXT4_SB(sb); struct inode *inode = sbi->s_buddy_cache; - mb_debug("load group %u\n", group); + mb_debug(1, "load group %u\n", group); blocks_per_page = PAGE_CACHE_SIZE / sb->s_blocksize; grp = ext4_get_group_info(sb, group); @@ -1851,7 +1852,7 @@ int ext4_mb_init_group(struct super_block *sb, ext4_group_t group) struct inode *inode = sbi->s_buddy_cache; struct page *page = NULL, *bitmap_page = NULL; - mb_debug("init group %u\n", group); + mb_debug(1, "init group %u\n", group); blocks_per_page = PAGE_CACHE_SIZE / sb->s_blocksize; this_grp = ext4_get_group_info(sb, group); /* @@ -2739,7 +2740,7 @@ static void ext4_mb_cleanup_pa(struct ext4_group_info *grp) kmem_cache_free(ext4_pspace_cachep, pa); } if (count) - mb_debug("mballoc: %u PAs left\n", count); + mb_debug(1, "mballoc: %u PAs left\n", count); } @@ -2820,7 +2821,7 @@ static void release_blocks_on_commit(journal_t *journal, transaction_t *txn) list_for_each_safe(l, ltmp, &txn->t_private_list) { entry = list_entry(l, struct ext4_free_data, list); - mb_debug("gonna free %u blocks in group %u (0x%p):", + mb_debug(1, "gonna free %u blocks in group %u (0x%p):", entry->count, entry->group, entry); err = ext4_mb_load_buddy(sb, entry->group, &e4b); @@ -2855,9 +2856,43 @@ static void release_blocks_on_commit(journal_t *journal, transaction_t *txn) ext4_mb_release_desc(&e4b); } - mb_debug("freed %u blocks in %u structures\n", count, count2); + mb_debug(1, "freed %u blocks in %u structures\n", count, count2); } +#ifdef CONFIG_EXT4_DEBUG +u8 mb_enable_debug __read_mostly; + +static struct dentry *debugfs_dir; +static struct dentry *debugfs_debug; + +static void __init ext4_create_debugfs_entry(void) +{ + debugfs_dir = debugfs_create_dir("ext4", NULL); + if (debugfs_dir) + debugfs_debug = debugfs_create_u8("mballoc-debug", + S_IRUGO | S_IWUSR, + debugfs_dir, + &mb_enable_debug); +} + +static void ext4_remove_debugfs_entry(void) +{ + debugfs_remove(debugfs_debug); + debugfs_remove(debugfs_dir); +} + +#else + +static void __init ext4_create_debugfs_entry(void) +{ +} + +static void ext4_remove_debugfs_entry(void) +{ +} + +#endif + int __init init_ext4_mballoc(void) { ext4_pspace_cachep = @@ -2885,6 +2920,7 @@ int __init init_ext4_mballoc(void) kmem_cache_destroy(ext4_ac_cachep); return -ENOMEM; } + ext4_create_debugfs_entry(); return 0; } @@ -2898,6 +2934,7 @@ void exit_ext4_mballoc(void) kmem_cache_destroy(ext4_pspace_cachep); kmem_cache_destroy(ext4_ac_cachep); kmem_cache_destroy(ext4_free_ext_cachep); + ext4_remove_debugfs_entry(); } @@ -3042,7 +3079,7 @@ static void ext4_mb_normalize_group_request(struct ext4_allocation_context *ac) ac->ac_g_ex.fe_len = EXT4_SB(sb)->s_stripe; else ac->ac_g_ex.fe_len = EXT4_SB(sb)->s_mb_group_prealloc; - mb_debug("#%u: goal %u blocks for locality group\n", + mb_debug(1, "#%u: goal %u blocks for locality group\n", current->pid, ac->ac_g_ex.fe_len); } @@ -3232,7 +3269,7 @@ ext4_mb_normalize_request(struct ext4_allocation_context *ac, ac->ac_flags |= EXT4_MB_HINT_TRY_GOAL; } - mb_debug("goal: %u(was %u) blocks at %u\n", (unsigned) size, + mb_debug(1, "goal: %u(was %u) blocks at %u\n", (unsigned) size, (unsigned) orig_size, (unsigned) start); } @@ -3281,7 +3318,7 @@ static void ext4_mb_use_inode_pa(struct ext4_allocation_context *ac, BUG_ON(pa->pa_free < len); pa->pa_free -= len; - mb_debug("use %llu/%u from inode pa %p\n", start, len, pa); + mb_debug(1, "use %llu/%u from inode pa %p\n", start, len, pa); } /* @@ -3305,7 +3342,7 @@ static void ext4_mb_use_group_pa(struct ext4_allocation_context *ac, * in on-disk bitmap -- see ext4_mb_release_context() * Other CPUs are prevented from allocating from this pa by lg_mutex */ - mb_debug("use %u/%u from group pa %p\n", pa->pa_lstart-len, len, pa); + mb_debug(1, "use %u/%u from group pa %p\n", pa->pa_lstart-len, len, pa); } /* @@ -3484,7 +3521,7 @@ void ext4_mb_generate_from_pa(struct super_block *sb, void *bitmap, preallocated += len; count++; } - mb_debug("prellocated %u for group %u\n", preallocated, group); + mb_debug(1, "prellocated %u for group %u\n", preallocated, group); } static void ext4_mb_pa_callback(struct rcu_head *head) @@ -3619,7 +3656,7 @@ ext4_mb_new_inode_pa(struct ext4_allocation_context *ac) pa->pa_deleted = 0; pa->pa_type = MB_INODE_PA; - mb_debug("new inode pa %p: %llu/%u for %u\n", pa, + mb_debug(1, "new inode pa %p: %llu/%u for %u\n", pa, pa->pa_pstart, pa->pa_len, pa->pa_lstart); trace_ext4_mb_new_inode_pa(ac, pa); @@ -3679,7 +3716,7 @@ ext4_mb_new_group_pa(struct ext4_allocation_context *ac) pa->pa_deleted = 0; pa->pa_type = MB_GROUP_PA; - mb_debug("new group pa %p: %llu/%u for %u\n", pa, + mb_debug(1, "new group pa %p: %llu/%u for %u\n", pa, pa->pa_pstart, pa->pa_len, pa->pa_lstart); trace_ext4_mb_new_group_pa(ac, pa); @@ -3758,7 +3795,7 @@ ext4_mb_release_inode_pa(struct ext4_buddy *e4b, struct buffer_head *bitmap_bh, next = mb_find_next_bit(bitmap_bh->b_data, end, bit); start = group * EXT4_BLOCKS_PER_GROUP(sb) + bit + le32_to_cpu(sbi->s_es->s_first_data_block); - mb_debug(" free preallocated %u/%u in group %u\n", + mb_debug(1, " free preallocated %u/%u in group %u\n", (unsigned) start, (unsigned) next - bit, (unsigned) group); free += next - bit; @@ -3849,7 +3886,7 @@ ext4_mb_discard_group_preallocations(struct super_block *sb, int busy = 0; int free = 0; - mb_debug("discard preallocation for group %u\n", group); + mb_debug(1, "discard preallocation for group %u\n", group); if (list_empty(&grp->bb_prealloc_list)) return 0; @@ -3973,7 +4010,7 @@ void ext4_discard_preallocations(struct inode *inode) return; } - mb_debug("discard preallocation for inode %lu\n", inode->i_ino); + mb_debug(1, "discard preallocation for inode %lu\n", inode->i_ino); trace_ext4_discard_preallocations(inode); INIT_LIST_HEAD(&list); @@ -4078,7 +4115,7 @@ static void ext4_mb_return_to_preallocation(struct inode *inode, { BUG_ON(!list_empty(&EXT4_I(inode)->i_prealloc_list)); } -#ifdef MB_DEBUG +#ifdef CONFIG_EXT4_DEBUG static void ext4_mb_show_ac(struct ext4_allocation_context *ac) { struct super_block *sb = ac->ac_sb; @@ -4227,7 +4264,7 @@ ext4_mb_initialize_context(struct ext4_allocation_context *ac, * locality group. this is a policy, actually */ ext4_mb_group_or_file(ac); - mb_debug("init ac: %u blocks @ %u, goal %u, flags %x, 2^%d, " + mb_debug(1, "init ac: %u blocks @ %u, goal %u, flags %x, 2^%d, " "left: %u/%u, right %u/%u to %swritable\n", (unsigned) ar->len, (unsigned) ar->logical, (unsigned) ar->goal, ac->ac_flags, ac->ac_2order, @@ -4249,7 +4286,7 @@ ext4_mb_discard_lg_preallocations(struct super_block *sb, struct ext4_prealloc_space *pa, *tmp; struct ext4_allocation_context *ac; - mb_debug("discard locality group preallocation\n"); + mb_debug(1, "discard locality group preallocation\n"); INIT_LIST_HEAD(&discard_list); ac = kmem_cache_alloc(ext4_ac_cachep, GFP_NOFS); diff --git a/fs/ext4/mballoc.h b/fs/ext4/mballoc.h index c96bb19f58f9..9db890d4d275 100644 --- a/fs/ext4/mballoc.h +++ b/fs/ext4/mballoc.h @@ -37,11 +37,19 @@ /* */ -#define MB_DEBUG__ -#ifdef MB_DEBUG -#define mb_debug(fmt, a...) printk(fmt, ##a) +#ifdef CONFIG_EXT4_DEBUG +extern u8 mb_enable_debug; + +#define mb_debug(n, fmt, a...) \ + do { \ + if ((n) <= mb_enable_debug) { \ + printk(KERN_DEBUG "(%s, %d): %s: ", \ + __FILE__, __LINE__, __func__); \ + printk(fmt, ## a); \ + } \ + } while (0) #else -#define mb_debug(fmt, a...) +#define mb_debug(n, fmt, a...) #endif /* -- 2.20.1