Illumos 5174 - add sdt probe for blocked read in dbuf_read()

delphixdelphix · behlendorf · commit 64dbba367944 · 2014-09-22T14:20:25.000-07:00
5174 add sdt probe for blocked read in dbuf_read() Reviewed by: Basil Crow <basil.crow@delphix.com> Reviewed by: Matthew Ahrens <mahrens@delphix.com> Reviewed by: Steven Hartland <killing@multiplay.co.uk> Reviewed by: Richard Elling <richard.elling@gmail.com> Reviewed by: Boris Protopopov <bprotopopov@hotmail.com> Reviewed by: Steven Hartland <killing@multiplay.co.uk> Reviewed by: Garrett D'Amore <garrett@damore.org> Approved by: Robert Mustacchi <rm@joyent.com> References: https://www.illumos.org/issues/5174 illumos/illumos-gate@f6164ad Ported by: Turbo Fredriksson <turbo@bayour.com> Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Closes #2710
diff --git a/module/zfs/dbuf.c b/module/zfs/dbuf.c
@@ -726,6 +726,8 @@ dbuf_read(dmu_buf_impl_t *db, zio_t *zio, uint32_t flags)
 			    db->db_state == DB_FILL) {
 				ASSERT(db->db_state == DB_READ ||
 				    (flags & DB_RF_HAVESTRUCT) == 0);
+				DTRACE_PROBE2(blocked__read, dmu_buf_impl_t *,
+				    db, zio_t *, zio);
 				cv_wait(&db->db_changed, &db->db_mtx);
 			}
 			if (db->db_state == DB_UNCACHED)

Original file line number	Diff line number	Diff line change
`@@ -726,6 +726,8 @@ dbuf_read(dmu_buf_impl_t db, zio_t zio, uint32_t flags)`
`726`	`726`	`db->db_state == DB_FILL) {`
`727`	`727`	`ASSERT(db->db_state == DB_READ \|\|`
`728`	`728`	`(flags & DB_RF_HAVESTRUCT) == 0);`
	`729`	`+ DTRACE_PROBE2(blocked__read, dmu_buf_impl_t *,`
	`730`	`+ db, zio_t *, zio);`
`729`	`731`	`cv_wait(&db->db_changed, &db->db_mtx);`
`730`	`732`	`}`
`731`	`733`	`if (db->db_state == DB_UNCACHED)`