f2fs: add tracepoint for tracing the page i/o

Add tracepoints for page i/o operations and block allocation
tracing during page read operation.

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Pankaj Kumar <pankaj.km@samsung.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
[Jaegeuk: combine and modify the tracepoint structures]
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>

2 files changed, 84 insertions, 2 deletions

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 3c31ec7d633d..8e8b14d714fc 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -21,6 +21,7 @@
 #include "f2fs.h"
 #include "node.h"
 #include "segment.h"
+#include <trace/events/f2fs.h>
 
 /*
  * Lock ordering for the change of data block address:
@@ -348,6 +349,8 @@ int f2fs_readpage(struct f2fs_sb_info *sbi, struct page *page,
         struct block_device *bdev = sbi->sb->s_bdev;
         struct bio *bio;
 
+        trace_f2fs_readpage(page, blk_addr, type);
+
         down_read(&sbi->bio_sem);
 
         /* Allocate a new bio */
@@ -388,14 +391,18 @@ static int get_data_block_ro(struct inode *inode, sector_t iblock,
         /* Get the page offset from the block offset(iblock) */
         pgofs = (pgoff_t)(iblock >> (PAGE_CACHE_SHIFT - blkbits));
 
-        if (check_extent_cache(inode, pgofs, bh_result))
+        if (check_extent_cache(inode, pgofs, bh_result)) {
+                trace_f2fs_get_data_block(inode, iblock, bh_result, 0);
                 return 0;
+        }
 
         /* When reading holes, we need its node page */
         set_new_dnode(&dn, inode, NULL, NULL, 0);
         err = get_dnode_of_data(&dn, pgofs, LOOKUP_NODE_RA);
-        if (err)
+        if (err) {
+                trace_f2fs_get_data_block(inode, iblock, bh_result, err);
                 return (err == -ENOENT) ? 0 : err;
+        }
 
         /* It does not support data allocation */
         BUG_ON(create);
@@ -420,6 +427,7 @@ static int get_data_block_ro(struct inode *inode, sector_t iblock,
                 bh_result->b_size = (i << blkbits);
         }
         f2fs_put_dnode(&dn);
+        trace_f2fs_get_data_block(inode, iblock, bh_result, 0);
         return 0;
 }
 
diff --git a/include/trace/events/f2fs.h b/include/trace/events/f2fs.h
index 4bbd19f79d27..924e69aa984f 100644
--- a/include/trace/events/f2fs.h
+++ b/include/trace/events/f2fs.h
@@ -8,6 +8,15 @@
 
 #define show_dev(entry)         MAJOR(entry->dev), MINOR(entry->dev)
 #define show_dev_ino(entry)     show_dev(entry), (unsigned long)entry->ino
+#define show_bio_type(type)                                             \
+        __print_symbolic(type,                                          \
+                { READ,         "READ" },                               \
+                { READA,        "READAHEAD" },                          \
+                { READ_SYNC,    "READ_SYNC" },                          \
+                { WRITE,        "WRITE" },                              \
+                { WRITE_SYNC,   "WRITE_SYNC" },                         \
+                { WRITE_FLUSH,  "WRITE_FLUSH" },                        \
+                { WRITE_FUA,    "WRITE_FUA" })
 
 DECLARE_EVENT_CLASS(f2fs__inode,
 
@@ -365,6 +374,71 @@ TRACE_EVENT(f2fs_truncate_partial_nodes,
                 __entry->err)
 );
 
+TRACE_EVENT_CONDITION(f2fs_readpage,
+
+        TP_PROTO(struct page *page, sector_t blkaddr, int type),
+
+        TP_ARGS(page, blkaddr, type),
+
+        TP_CONDITION(page->mapping),
+
+        TP_STRUCT__entry(
+                __field(dev_t,  dev)
+                __field(ino_t,  ino)
+                __field(pgoff_t,        index)
+                __field(sector_t,       blkaddr)
+                __field(int,    type)
+        ),
+
+        TP_fast_assign(
+                __entry->dev            = page->mapping->host->i_sb->s_dev;
+                __entry->ino            = page->mapping->host->i_ino;
+                __entry->index          = page->index;
+                __entry->blkaddr        = blkaddr;
+                __entry->type           = type;
+        ),
+
+        TP_printk("dev = (%d,%d), ino = %lu, page_index = 0x%lx, "
+                "blkaddr = 0x%llx, bio_type = %s",
+                show_dev_ino(__entry),
+                (unsigned long)__entry->index,
+                (unsigned long long)__entry->blkaddr,
+                show_bio_type(__entry->type))
+);
+
+TRACE_EVENT(f2fs_get_data_block,
+        TP_PROTO(struct inode *inode, sector_t iblock,
+                                struct buffer_head *bh, int ret),
+
+        TP_ARGS(inode, iblock, bh, ret),
+
+        TP_STRUCT__entry(
+                __field(dev_t,  dev)
+                __field(ino_t,  ino)
+                __field(sector_t,       iblock)
+                __field(sector_t,       bh_start)
+                __field(size_t, bh_size)
+                __field(int,    ret)
+        ),
+
+        TP_fast_assign(
+                __entry->dev            = inode->i_sb->s_dev;
+                __entry->ino            = inode->i_ino;
+                __entry->iblock         = iblock;
+                __entry->bh_start       = bh->b_blocknr;
+                __entry->bh_size        = bh->b_size;
+                __entry->ret            = ret;
+        ),
+
+        TP_printk("dev = (%d,%d), ino = %lu, file offset = %llu, "
+                "start blkaddr = 0x%llx, len = 0x%llx bytes, err = %d",
+                show_dev_ino(__entry),
+                (unsigned long long)__entry->iblock,
+                (unsigned long long)__entry->bh_start,
+                (unsigned long long)__entry->bh_size,
+                __entry->ret)
+);
+
 #endif /* _TRACE_F2FS_H */
 
  /* This part must be outside protection */