btrfs: tracepoints: simplify raid56 events

After commit 6bfd0133 ("btrfs: raid56: switch scrub path to use a
single function"), the raid56 implementation no longer uses different
endio functions for RMW/recover/scrub.

All read operations end in submit_read_wait_bio_list(), while all write
operations end in submit_write_bios().  This means quite some trace
events are out-of-date and no longer utilized.

This patch would unify the trace events into just two:

- trace_raid56_read()
  Replaces trace_raid56_read_partial(), trace_raid56_scrub_read() and
  trace_raid56_scrub_read_recover().

- trace_raid56_write()
  Replaces trace_raid56_write_stripe() and
  trace_raid56_scrub_write_stripe().
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

fs/btrfs/raid56.c

@@ -1513,11 +1513,11 @@ static void submit_read_wait_bio_list(struct btrfs_raid_bio *rbio,
 	while ((bio = bio_list_pop(bio_list))) {
 		bio->bi_end_io = raid_wait_read_end_io;
 
-		if (trace_raid56_scrub_read_recover_enabled()) {
+		if (trace_raid56_read_enabled()) {
 			struct raid56_bio_trace_info trace_info = { 0 };
 
 			bio_get_trace_info(rbio, bio, &trace_info);
-			trace_raid56_scrub_read_recover(rbio, bio, &trace_info);
+			trace_raid56_read(rbio, bio, &trace_info);
 		}
 		submit_bio(bio);
 	}
@@ -2191,11 +2191,11 @@ static void submit_write_bios(struct btrfs_raid_bio *rbio,
 	while ((bio = bio_list_pop(bio_list))) {
 		bio->bi_end_io = raid_wait_write_end_io;
 
-		if (trace_raid56_write_stripe_enabled()) {
+		if (trace_raid56_write_enabled()) {
 			struct raid56_bio_trace_info trace_info = { 0 };
 
 			bio_get_trace_info(rbio, bio, &trace_info);
-			trace_raid56_write_stripe(rbio, bio, &trace_info);
+			trace_raid56_write(rbio, bio, &trace_info);
 		}
 		submit_bio(bio);
 	}

include/trace/events/btrfs.h

@@ -2482,7 +2482,7 @@ DECLARE_EVENT_CLASS(btrfs_raid56_bio,
 		__entry->offset, __entry->opf, __entry->physical, __entry->len)
 );
 
-DEFINE_EVENT(btrfs_raid56_bio, raid56_read_partial,
+DEFINE_EVENT(btrfs_raid56_bio, raid56_read,
 	TP_PROTO(const struct btrfs_raid_bio *rbio,
 		 const struct bio *bio,
 		 const struct raid56_bio_trace_info *trace_info),
@@ -2490,32 +2490,7 @@ DEFINE_EVENT(btrfs_raid56_bio, raid56_read_partial,
 	TP_ARGS(rbio, bio, trace_info)
 );
 
-DEFINE_EVENT(btrfs_raid56_bio, raid56_write_stripe,
-	TP_PROTO(const struct btrfs_raid_bio *rbio,
-		 const struct bio *bio,
-		 const struct raid56_bio_trace_info *trace_info),
-
-	TP_ARGS(rbio, bio, trace_info)
-);
-
-
-DEFINE_EVENT(btrfs_raid56_bio, raid56_scrub_write_stripe,
-	TP_PROTO(const struct btrfs_raid_bio *rbio,
-		 const struct bio *bio,
-		 const struct raid56_bio_trace_info *trace_info),
-
-	TP_ARGS(rbio, bio, trace_info)
-);
-
-DEFINE_EVENT(btrfs_raid56_bio, raid56_scrub_read,
-	TP_PROTO(const struct btrfs_raid_bio *rbio,
-		 const struct bio *bio,
-		 const struct raid56_bio_trace_info *trace_info),
-
-	TP_ARGS(rbio, bio, trace_info)
-);
-
-DEFINE_EVENT(btrfs_raid56_bio, raid56_scrub_read_recover,
+DEFINE_EVENT(btrfs_raid56_bio, raid56_write,
 	TP_PROTO(const struct btrfs_raid_bio *rbio,
 		 const struct bio *bio,
 		 const struct raid56_bio_trace_info *trace_info),