7867 ARC space accounting leak

avg-I · ahrens · commit aa1f740d5600 · 2017-03-07T09:15:39.000-08:00
Reviewed by: Matthew Ahrens <mahrens@delphix.com> Reviewed by: Dan Kimmel <dan.kimmel@delphix.com> Closes #300
diff --git a/usr/src/uts/common/fs/zfs/arc.c b/usr/src/uts/common/fs/zfs/arc.c
@@ -2587,6 +2587,12 @@ arc_hdr_free_on_write(arc_buf_hdr_t *hdr)
 		    size, hdr);
 	}
 	(void) refcount_remove_many(&state->arcs_size, size, hdr);
+	if (type == ARC_BUFC_METADATA) {
+		arc_space_return(size, ARC_SPACE_META);
+	} else {
+		ASSERT(type == ARC_BUFC_DATA);
+		arc_space_return(size, ARC_SPACE_DATA);
+	}
 
 	l2arc_free_data_on_write(hdr->b_l1hdr.b_pdata, size, type);
 }

Original file line number	Diff line number	Diff line change
`@@ -2587,6 +2587,12 @@ arc_hdr_free_on_write(arc_buf_hdr_t *hdr)`
`2587`	`2587`	`size, hdr);`
`2588`	`2588`	`}`
`2589`	`2589`	`(void) refcount_remove_many(&state->arcs_size, size, hdr);`
	`2590`	`+ if (type == ARC_BUFC_METADATA) {`
	`2591`	`+ arc_space_return(size, ARC_SPACE_META);`
	`2592`	`+ } else {`
	`2593`	`+ ASSERT(type == ARC_BUFC_DATA);`
	`2594`	`+ arc_space_return(size, ARC_SPACE_DATA);`
	`2595`	`+ }`
`2590`	`2596`
`2591`	`2597`	`l2arc_free_data_on_write(hdr->b_l1hdr.b_pdata, size, type);`
`2592`	`2598`	`}`