ext4: Add new tracepoints to debug delayed allocation space functions

Add tracepoints for ext4_da_reserve_space(),
ext4_da_update_reserve_space(), and ext4_da_release_space().

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

2 files changed, 103 insertions, 0 deletions

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 3e8afd969236..1a3d7b232cd7 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -1061,6 +1061,7 @@ void ext4_da_update_reserve_space(struct inode *inode,
         int mdb_free = 0, allocated_meta_blocks = 0;
 
         spin_lock(&ei->i_block_reservation_lock);
+        trace_ext4_da_update_reserve_space(inode, used);
         if (unlikely(used > ei->i_reserved_data_blocks)) {
                 ext4_msg(inode->i_sb, KERN_NOTICE, "%s: ino %lu, used %d "
                          "with only %d reserved data blocks\n",
@@ -1846,6 +1847,7 @@ repeat:
         spin_lock(&ei->i_block_reservation_lock);
         md_reserved = ei->i_reserved_meta_blocks;
         md_needed = ext4_calc_metadata_amount(inode, lblock);
+        trace_ext4_da_reserve_space(inode, md_needed);
         spin_unlock(&ei->i_block_reservation_lock);
 
         /*
diff --git a/include/trace/events/ext4.h b/include/trace/events/ext4.h
index d0b6cd3afb2f..2aa6aa3e8f61 100644
--- a/include/trace/events/ext4.h
+++ b/include/trace/events/ext4.h
@@ -874,6 +874,107 @@ TRACE_EVENT(ext4_forget,
                   __entry->mode, __entry->is_metadata, __entry->block)
 );
 
+TRACE_EVENT(ext4_da_update_reserve_space,
+        TP_PROTO(struct inode *inode, int used_blocks),
+
+        TP_ARGS(inode, used_blocks),
+
+        TP_STRUCT__entry(
+                __field(        dev_t,  dev                     )
+                __field(        ino_t,  ino                     )
+                __field(        umode_t, mode                   )
+                __field(        __u64,  i_blocks                )
+                __field(        int,    used_blocks             )
+                __field(        int,    reserved_data_blocks    )
+                __field(        int,    reserved_meta_blocks    )
+                __field(        int,    allocated_meta_blocks   )
+        ),
+
+        TP_fast_assign(
+                __entry->dev    = inode->i_sb->s_dev;
+                __entry->ino    = inode->i_ino;
+                __entry->mode   = inode->i_mode;
+                __entry->i_blocks = inode->i_blocks;
+                __entry->used_blocks = used_blocks;
+                __entry->reserved_data_blocks = EXT4_I(inode)->i_reserved_data_blocks;
+                __entry->reserved_meta_blocks = EXT4_I(inode)->i_reserved_meta_blocks;
+                __entry->allocated_meta_blocks = EXT4_I(inode)->i_allocated_meta_blocks;
+        ),
+
+        TP_printk("dev %s ino %lu mode 0%o i_blocks %llu used_blocks %d reserved_data_blocks %d reserved_meta_blocks %d allocated_meta_blocks %d",
+                  jbd2_dev_to_name(__entry->dev), (unsigned long) __entry->ino,
+                  __entry->mode,  (unsigned long long) __entry->i_blocks,
+                  __entry->used_blocks, __entry->reserved_data_blocks,
+                  __entry->reserved_meta_blocks, __entry->allocated_meta_blocks)
+);
+
+TRACE_EVENT(ext4_da_reserve_space,
+        TP_PROTO(struct inode *inode, int md_needed),
+
+        TP_ARGS(inode, md_needed),
+
+        TP_STRUCT__entry(
+                __field(        dev_t,  dev                     )
+                __field(        ino_t,  ino                     )
+                __field(        umode_t, mode                   )
+                __field(        __u64,  i_blocks                )
+                __field(        int,    md_needed               )
+                __field(        int,    reserved_data_blocks    )
+                __field(        int,    reserved_meta_blocks    )
+        ),
+
+        TP_fast_assign(
+                __entry->dev    = inode->i_sb->s_dev;
+                __entry->ino    = inode->i_ino;
+                __entry->mode   = inode->i_mode;
+                __entry->i_blocks = inode->i_blocks;
+                __entry->md_needed = md_needed;
+                __entry->reserved_data_blocks = EXT4_I(inode)->i_reserved_data_blocks;
+                __entry->reserved_meta_blocks = EXT4_I(inode)->i_reserved_meta_blocks;
+        ),
+
+        TP_printk("dev %s ino %lu mode 0%o i_blocks %llu md_needed %d reserved_data_blocks %d reserved_meta_blocks %d",
+                  jbd2_dev_to_name(__entry->dev), (unsigned long) __entry->ino,
+                  __entry->mode, (unsigned long long) __entry->i_blocks,
+                  __entry->md_needed, __entry->reserved_data_blocks,
+                  __entry->reserved_meta_blocks)
+);
+
+TRACE_EVENT(ext4_da_release_space,
+        TP_PROTO(struct inode *inode, int freed_blocks),
+
+        TP_ARGS(inode, freed_blocks),
+
+        TP_STRUCT__entry(
+                __field(        dev_t,  dev                     )
+                __field(        ino_t,  ino                     )
+                __field(        umode_t, mode                   )
+                __field(        __u64,  i_blocks                )
+                __field(        int,    freed_blocks            )
+                __field(        int,    reserved_data_blocks    )
+                __field(        int,    reserved_meta_blocks    )
+                __field(        int,    allocated_meta_blocks   )
+        ),
+
+        TP_fast_assign(
+                __entry->dev    = inode->i_sb->s_dev;
+                __entry->ino    = inode->i_ino;
+                __entry->mode   = inode->i_mode;
+                __entry->i_blocks = inode->i_blocks;
+                __entry->freed_blocks = freed_blocks;
+                __entry->reserved_data_blocks = EXT4_I(inode)->i_reserved_data_blocks;
+                __entry->reserved_meta_blocks = EXT4_I(inode)->i_reserved_meta_blocks;
+                __entry->allocated_meta_blocks = EXT4_I(inode)->i_allocated_meta_blocks;
+        ),
+
+        TP_printk("dev %s ino %lu mode 0%o i_blocks %llu freed_blocks %d reserved_data_blocks %d reserved_meta_blocks %d allocated_meta_blocks %d",
+                  jbd2_dev_to_name(__entry->dev), (unsigned long) __entry->ino,
+                  __entry->mode, (unsigned long long) __entry->i_blocks,
+                  __entry->freed_blocks, __entry->reserved_data_blocks,
+                  __entry->reserved_meta_blocks, __entry->allocated_meta_blocks)
+);
+
+
 #endif /* _TRACE_EXT4_H */
 
 /* This part must be outside protection */