Btrfs: add tracepoints for flush events
We want to track when we're triggering flushing from our reservation code and
what flushing is being done when we start flushing. Thanks,
Signed-off-by: Josef Bacik <jbacik@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 2e04c9d..83a6a93 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -2626,6 +2626,15 @@
BTRFS_RESERVE_FLUSH_ALL,
};
+enum btrfs_flush_state {
+ FLUSH_DELAYED_ITEMS_NR = 1,
+ FLUSH_DELAYED_ITEMS = 2,
+ FLUSH_DELALLOC = 3,
+ FLUSH_DELALLOC_WAIT = 4,
+ ALLOC_CHUNK = 5,
+ COMMIT_TRANS = 6,
+};
+
int btrfs_check_data_free_space(struct inode *inode, u64 start, u64 len);
int btrfs_alloc_data_chunk_ondemand(struct inode *inode, u64 bytes);
void btrfs_free_reserved_data_space(struct inode *inode, u64 start, u64 len);
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 5d24ec44..31ded6a 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -4835,15 +4835,6 @@
return btrfs_commit_transaction(trans, root);
}
-enum flush_state {
- FLUSH_DELAYED_ITEMS_NR = 1,
- FLUSH_DELAYED_ITEMS = 2,
- FLUSH_DELALLOC = 3,
- FLUSH_DELALLOC_WAIT = 4,
- ALLOC_CHUNK = 5,
- COMMIT_TRANS = 6,
-};
-
struct reserve_ticket {
u64 bytes;
int error;
@@ -4901,6 +4892,8 @@
break;
}
+ trace_btrfs_flush_space(root->fs_info, space_info->flags, num_bytes,
+ orig_bytes, state, ret);
return ret;
}
@@ -5178,6 +5171,10 @@
list_add_tail(&ticket.list, &space_info->tickets);
if (!space_info->flush) {
space_info->flush = 1;
+ trace_btrfs_trigger_flush(root->fs_info,
+ space_info->flags,
+ orig_bytes, flush,
+ "enospc");
queue_work(system_unbound_wq,
&root->fs_info->async_reclaim_work);
}
@@ -5194,9 +5191,14 @@
*/
if (!root->fs_info->log_root_recovering &&
need_do_async_reclaim(space_info, root->fs_info, used) &&
- !work_busy(&root->fs_info->async_reclaim_work))
+ !work_busy(&root->fs_info->async_reclaim_work)) {
+ trace_btrfs_trigger_flush(root->fs_info,
+ space_info->flags,
+ orig_bytes, flush,
+ "preempt");
queue_work(system_unbound_wq,
&root->fs_info->async_reclaim_work);
+ }
}
spin_unlock(&space_info->lock);
if (!ret || flush == BTRFS_RESERVE_NO_FLUSH)
diff --git a/include/trace/events/btrfs.h b/include/trace/events/btrfs.h
index 985e01b..226c7f28 100644
--- a/include/trace/events/btrfs.h
+++ b/include/trace/events/btrfs.h
@@ -784,6 +784,88 @@
__entry->bytes)
);
+#define show_flush_action(action) \
+ __print_symbolic(action, \
+ { BTRFS_RESERVE_NO_FLUSH, "BTRFS_RESERVE_NO_FLUSH"}, \
+ { BTRFS_RESERVE_FLUSH_LIMIT, "BTRFS_RESERVE_FLUSH_LIMIT"}, \
+ { BTRFS_RESERVE_FLUSH_ALL, "BTRFS_RESERVE_FLUSH_ALL"})
+
+TRACE_EVENT(btrfs_trigger_flush,
+
+ TP_PROTO(struct btrfs_fs_info *fs_info, u64 flags, u64 bytes,
+ int flush, char *reason),
+
+ TP_ARGS(fs_info, flags, bytes, flush, reason),
+
+ TP_STRUCT__entry(
+ __array( u8, fsid, BTRFS_UUID_SIZE )
+ __field( u64, flags )
+ __field( u64, bytes )
+ __field( int, flush )
+ __string( reason, reason )
+ ),
+
+ TP_fast_assign(
+ memcpy(__entry->fsid, fs_info->fsid, BTRFS_UUID_SIZE);
+ __entry->flags = flags;
+ __entry->bytes = bytes;
+ __entry->flush = flush;
+ __assign_str(reason, reason)
+ ),
+
+ TP_printk("%pU: %s: flush = %d(%s), flags = %llu(%s), bytes = %llu",
+ __entry->fsid, __get_str(reason), __entry->flush,
+ show_flush_action(__entry->flush),
+ (unsigned long long)__entry->flags,
+ __print_flags((unsigned long)__entry->flags, "|",
+ BTRFS_GROUP_FLAGS),
+ (unsigned long long)__entry->bytes)
+);
+
+#define show_flush_state(state) \
+ __print_symbolic(state, \
+ { FLUSH_DELAYED_ITEMS_NR, "FLUSH_DELAYED_ITEMS_NR"}, \
+ { FLUSH_DELAYED_ITEMS, "FLUSH_DELAYED_ITEMS"}, \
+ { FLUSH_DELALLOC, "FLUSH_DELALLOC"}, \
+ { FLUSH_DELALLOC_WAIT, "FLUSH_DELALLOC_WAIT"}, \
+ { ALLOC_CHUNK, "ALLOC_CHUNK"}, \
+ { COMMIT_TRANS, "COMMIT_TRANS"})
+
+TRACE_EVENT(btrfs_flush_space,
+
+ TP_PROTO(struct btrfs_fs_info *fs_info, u64 flags, u64 num_bytes,
+ u64 orig_bytes, int state, int ret),
+
+ TP_ARGS(fs_info, flags, num_bytes, orig_bytes, state, ret),
+
+ TP_STRUCT__entry(
+ __array( u8, fsid, BTRFS_UUID_SIZE )
+ __field( u64, flags )
+ __field( u64, num_bytes )
+ __field( u64, orig_bytes )
+ __field( int, state )
+ __field( int, ret )
+ ),
+
+ TP_fast_assign(
+ memcpy(__entry->fsid, fs_info->fsid, BTRFS_UUID_SIZE);
+ __entry->flags = flags;
+ __entry->num_bytes = num_bytes;
+ __entry->orig_bytes = orig_bytes;
+ __entry->state = state;
+ __entry->ret = ret;
+ ),
+
+ TP_printk("%pU: state = %d(%s), flags = %llu(%s), num_bytes = %llu, "
+ "orig_bytes = %llu, ret = %d", __entry->fsid, __entry->state,
+ show_flush_state(__entry->state),
+ (unsigned long long)__entry->flags,
+ __print_flags((unsigned long)__entry->flags, "|",
+ BTRFS_GROUP_FLAGS),
+ (unsigned long long)__entry->num_bytes,
+ (unsigned long long)__entry->orig_bytes, __entry->ret)
+);
+
DECLARE_EVENT_CLASS(btrfs__reserved_extent,
TP_PROTO(struct btrfs_root *root, u64 start, u64 len),