[PATCH RESEND] erofs: refine readahead tracepoint

[Gao Xiang <hsiangkao@linux.alibaba.com>]

 - trace_erofs_readpages => trace_erofs_readahead;

 - Rename a redundant statement `nrpages = readahead_count(rac);`;

 - Move the tracepoint to the beginning of z_erofs_readahead().

Signed-off-by: Gao Xiang <hsiangkao@linux.alibaba.com>
---
replace a stale version..

 fs/erofs/fileio.c            | 2 +-
 fs/erofs/zdata.c             | 5 ++---
 include/trace/events/erofs.h | 2 +-
 3 files changed, 4 insertions(+), 5 deletions(-)

diff --git a/fs/erofs/fileio.c b/fs/erofs/fileio.c
index 60c7cc4c105c..94fff404db81 100644
--- a/fs/erofs/fileio.c
+++ b/fs/erofs/fileio.c
@@ -180,7 +180,7 @@ static void erofs_fileio_readahead(struct readahead_control *rac)
 	struct folio *folio;
 	int err;
 
-	trace_erofs_readpages(inode, readahead_index(rac),
+	trace_erofs_readahead(inode, readahead_index(rac),
 			      readahead_count(rac), true);
 	while ((folio = readahead_folio(rac))) {
 		err = erofs_fileio_scan_folio(&io, folio);
diff --git a/fs/erofs/zdata.c b/fs/erofs/zdata.c
index b8e6b76c23d5..29541e0787b8 100644
--- a/fs/erofs/zdata.c
+++ b/fs/erofs/zdata.c
@@ -1855,13 +1855,12 @@ static void z_erofs_readahead(struct readahead_control *rac)
 {
 	struct inode *const inode = rac->mapping->host;
 	Z_EROFS_DEFINE_FRONTEND(f, inode, readahead_pos(rac));
-	struct folio *head = NULL, *folio;
 	unsigned int nrpages = readahead_count(rac);
+	struct folio *head = NULL, *folio;
 	int err;
 
+	trace_erofs_readahead(inode, readahead_index(rac), nrpages, false);
 	z_erofs_pcluster_readmore(&f, rac, true);
-	nrpages = readahead_count(rac);
-	trace_erofs_readpages(inode, readahead_index(rac), nrpages, false);
 	while ((folio = readahead_folio(rac))) {
 		folio->private = head;
 		head = folio;
diff --git a/include/trace/events/erofs.h b/include/trace/events/erofs.h
index c69c7b1e41d1..a5f4b9234f46 100644
--- a/include/trace/events/erofs.h
+++ b/include/trace/events/erofs.h
@@ -113,7 +113,7 @@ TRACE_EVENT(erofs_read_folio,
 		__entry->raw)
 );
 
-TRACE_EVENT(erofs_readpages,
+TRACE_EVENT(erofs_readahead,
 
 	TP_PROTO(struct inode *inode, pgoff_t start, unsigned int nrpage,
 		bool raw),
-- 
2.43.5