Module Name: src
Committed By: ad
Date: Sat Mar 21 22:04:17 UTC 2020
Modified Files:
src/sys/sys [ad-namecache]: namei.src
Log Message:
Move nc_key up, so cache_lookup_entry() only needs to touch one cache line
at each step.
To generate a diff of this commit:
cvs rdiff -u -r1.47.2.7 -r1.47.2.8 src/sys/sys/namei.src
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/sys/namei.src
diff -u src/sys/sys/namei.src:1.47.2.7 src/sys/sys/namei.src:1.47.2.8
--- src/sys/sys/namei.src:1.47.2.7 Wed Mar 4 20:21:05 2020
+++ src/sys/sys/namei.src Sat Mar 21 22:04:17 2020
@@ -1,4 +1,4 @@
-/* $NetBSD: namei.src,v 1.47.2.7 2020/03/04 20:21:05 ad Exp $ */
+/* $NetBSD: namei.src,v 1.47.2.8 2020/03/21 22:04:17 ad Exp $ */
/*
* Copyright (c) 1985, 1989, 1991, 1993
@@ -199,11 +199,12 @@ NAMEIFL PARAMASK 0x02ef800 /* mask of pa
#define NCHNAMLEN sizeof(((struct namecache *)NULL)->nc_name)
/*
- * Namecache entry.
+ * Namecache entry.
*
* This structure describes the elements in the cache of recent names looked
* up by namei. It's carefully sized to take up 128 bytes on _LP64, to make
- * good use of space and the CPU caches.
+ * good use of space and the CPU caches. Items used during RB tree lookup
+ * (nc_tree, nc_key) are clustered at the start of the structure.
*
* Field markings and their corresponding locks:
*
@@ -216,11 +217,11 @@ NAMEIFL PARAMASK 0x02ef800 /* mask of pa
struct nchnode;
struct namecache {
struct rb_node nc_tree; /* d red-black tree, must be first */
+ int64_t nc_key; /* - hash key */
TAILQ_ENTRY(namecache) nc_list; /* v vp's list of cache entries */
TAILQ_ENTRY(namecache) nc_lru; /* l pseudo-lru chain */
struct vnode *nc_dvp; /* - vnode of parent of name */
struct vnode *nc_vp; /* - vnode the name refers to */
- int64_t nc_key; /* - hash key */
int nc_lrulist; /* l which LRU list its on */
short nc_nlen; /* - length of the name */
char nc_whiteout; /* - true if a whiteout */
