[src/trunk]: src/sys/kern pcq(9): Explain why store need not be atomic in pcq...

[riastradh <riastradh%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/bff767b7127c
branches:  trunk
changeset: 373657:bff767b7127c
user:      riastradh <riastradh%NetBSD.org@localhost>
date:      Thu Feb 23 03:01:35 2023 +0000

description:
pcq(9): Explain why store need not be atomic in pcq_get.

No functional change intended.

diffstat:

 sys/kern/subr_pcq.c |  8 ++++++--
 1 files changed, 6 insertions(+), 2 deletions(-)

diffs (29 lines):

diff -r 649eeac6ad6c -r bff767b7127c sys/kern/subr_pcq.c
--- a/sys/kern/subr_pcq.c       Thu Feb 23 03:01:22 2023 +0000
+++ b/sys/kern/subr_pcq.c       Thu Feb 23 03:01:35 2023 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: subr_pcq.c,v 1.15 2023/02/23 03:01:22 riastradh Exp $  */
+/*     $NetBSD: subr_pcq.c,v 1.16 2023/02/23 03:01:35 riastradh Exp $  */
 
 /*-
  * Copyright (c) 2009, 2019 The NetBSD Foundation, Inc.
@@ -34,7 +34,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: subr_pcq.c,v 1.15 2023/02/23 03:01:22 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: subr_pcq.c,v 1.16 2023/02/23 03:01:35 riastradh Exp $");
 
 #include <sys/param.h>
 #include <sys/types.h>
@@ -168,6 +168,10 @@
                 */
                return NULL;
        }
+       /*
+        * We have exclusive access to this slot, so no need for
+        * atomic_store_*.
+        */
        pcq->pcq_items[c] = NULL;
        c = pcq_advance(pcq, c);
        nv = pcq_combine(p, c);