ext4: lookup block mapping in extent status tree
After tracking all extent status, we already have a extent cache in
memory. Every time we want to lookup a block mapping, we can first
try to lookup it in extent status tree to avoid a potential disk I/O.
A new function called ext4_es_lookup_extent is defined to finish this
work. When we try to lookup a block mapping, we always call
ext4_map_blocks and/or ext4_da_map_blocks. So in these functions we
first try to lookup a block mapping in extent status tree.
A new flag EXT4_GET_BLOCKS_NO_PUT_HOLE is used in ext4_da_map_blocks
in order not to put a hole into extent status tree because this hole
will be converted to delayed extent in the tree immediately.
Signed-off-by: Zheng Liu <wenqing.lz@taobao.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: Jan kara <jack@suse.cz>
diff --git a/include/trace/events/ext4.h b/include/trace/events/ext4.h
index c121cdf..1e590b6 100644
--- a/include/trace/events/ext4.h
+++ b/include/trace/events/ext4.h
@@ -2199,6 +2199,62 @@
__entry->pblk, __entry->status)
);
+TRACE_EVENT(ext4_es_lookup_extent_enter,
+ TP_PROTO(struct inode *inode, ext4_lblk_t lblk),
+
+ TP_ARGS(inode, lblk),
+
+ TP_STRUCT__entry(
+ __field( dev_t, dev )
+ __field( ino_t, ino )
+ __field( ext4_lblk_t, lblk )
+ ),
+
+ TP_fast_assign(
+ __entry->dev = inode->i_sb->s_dev;
+ __entry->ino = inode->i_ino;
+ __entry->lblk = lblk;
+ ),
+
+ TP_printk("dev %d,%d ino %lu lblk %u",
+ MAJOR(__entry->dev), MINOR(__entry->dev),
+ (unsigned long) __entry->ino, __entry->lblk)
+);
+
+TRACE_EVENT(ext4_es_lookup_extent_exit,
+ TP_PROTO(struct inode *inode, struct extent_status *es,
+ int found),
+
+ TP_ARGS(inode, es, found),
+
+ TP_STRUCT__entry(
+ __field( dev_t, dev )
+ __field( ino_t, ino )
+ __field( ext4_lblk_t, lblk )
+ __field( ext4_lblk_t, len )
+ __field( ext4_fsblk_t, pblk )
+ __field( unsigned long long, status )
+ __field( int, found )
+ ),
+
+ TP_fast_assign(
+ __entry->dev = inode->i_sb->s_dev;
+ __entry->ino = inode->i_ino;
+ __entry->lblk = es->es_lblk;
+ __entry->len = es->es_len;
+ __entry->pblk = ext4_es_pblock(es);
+ __entry->status = ext4_es_status(es);
+ __entry->found = found;
+ ),
+
+ TP_printk("dev %d,%d ino %lu found %d [%u/%u) %llu %llx",
+ MAJOR(__entry->dev), MINOR(__entry->dev),
+ (unsigned long) __entry->ino, __entry->found,
+ __entry->lblk, __entry->len,
+ __entry->found ? __entry->pblk : 0,
+ __entry->found ? __entry->status : 0)
+);
+
#endif /* _TRACE_EXT4_H */
/* This part must be outside protection */