[src/trunk]: src/sys/arch/mips/rmi mips/rmixl: Insert appropriate membars aro...

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

details:   https://anonhg.NetBSD.org/src/rev/8723dfea1c9f
branches:  trunk
changeset: 365147:8723dfea1c9f
user:      riastradh <riastradh%NetBSD.org@localhost>
date:      Sat Apr 09 23:34:50 2022 +0000

description:
mips/rmixl: Insert appropriate membars around IPIs.

diffstat:

 sys/arch/mips/rmi/rmixl_intr.c |  8 +++++---
 1 files changed, 5 insertions(+), 3 deletions(-)

diffs (37 lines):

diff -r ef89f164c616 -r 8723dfea1c9f sys/arch/mips/rmi/rmixl_intr.c
--- a/sys/arch/mips/rmi/rmixl_intr.c    Sat Apr 09 23:34:40 2022 +0000
+++ b/sys/arch/mips/rmi/rmixl_intr.c    Sat Apr 09 23:34:50 2022 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: rmixl_intr.c,v 1.12 2016/08/26 15:45:48 skrll Exp $    */
+/*     $NetBSD: rmixl_intr.c,v 1.13 2022/04/09 23:34:50 riastradh Exp $        */
 
 /*-
  * Copyright (c) 2007 Ruslan Ermilov and Vsevolod Lobko.
@@ -64,7 +64,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: rmixl_intr.c,v 1.12 2016/08/26 15:45:48 skrll Exp $");
+__KERNEL_RCSID(0, "$NetBSD: rmixl_intr.c,v 1.13 2022/04/09 23:34:50 riastradh Exp $");
 
 #include "opt_ddb.h"
 #include "opt_multiprocessor.h"
@@ -967,6 +967,7 @@
          | (RMIXL_INTRVEC_IPI + tag);
 
        mutex_enter(&rmixl_ipi_lock);
+       membar_release();
        atomic_or_64(&ci->ci_request_ipis, req);
        RMIXL_PICREG_WRITE(RMIXL_PIC_IPIBASE, r);
        mutex_exit(&rmixl_ipi_lock);
@@ -984,8 +985,9 @@
        KASSERT((uintptr_t)arg < NIPIS);
 
        /* if the request is clear, it was previously processed */
-       if ((ci->ci_request_ipis & ipi_mask) == 0)
+       if ((atomic_load_relaxed(&ci->ci_request_ipis) & ipi_mask) == 0)
                return 0;
+       membar_acquire();
 
        atomic_or_64(&ci->ci_active_ipis, ipi_mask);
        atomic_and_64(&ci->ci_request_ipis, ~ipi_mask);