[src/trunk]: src/sys/external/bsd/drm2/linux linux: Use pointer indirection f...

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

details:   https://anonhg.NetBSD.org/src/rev/4effd22626d0
branches:  trunk
changeset: 1028717:4effd22626d0
user:      riastradh <riastradh%NetBSD.org@localhost>
date:      Sun Dec 19 11:50:54 2021 +0000

description:
linux: Use pointer indirection for irq_work_cpu.

Can't store locks in percpu since it moves around.

diffstat:

 sys/external/bsd/drm2/linux/linux_irq_work.c |  21 +++++++++++++--------
 1 files changed, 13 insertions(+), 8 deletions(-)

diffs (80 lines):

diff -r 8a05cab8471a -r 4effd22626d0 sys/external/bsd/drm2/linux/linux_irq_work.c
--- a/sys/external/bsd/drm2/linux/linux_irq_work.c      Sun Dec 19 11:50:47 2021 +0000
+++ b/sys/external/bsd/drm2/linux/linux_irq_work.c      Sun Dec 19 11:50:54 2021 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: linux_irq_work.c,v 1.1 2021/12/19 11:49:57 riastradh Exp $     */
+/*     $NetBSD: linux_irq_work.c,v 1.2 2021/12/19 11:50:54 riastradh Exp $     */
 
 /*-
  * Copyright (c) 2021 The NetBSD Foundation, Inc.
@@ -30,12 +30,13 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: linux_irq_work.c,v 1.1 2021/12/19 11:49:57 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: linux_irq_work.c,v 1.2 2021/12/19 11:50:54 riastradh Exp $");
 
 #include <sys/param.h>
 
 #include <sys/atomic.h>
 #include <sys/intr.h>
+#include <sys/kmem.h>
 #include <sys/mutex.h>
 #include <sys/percpu.h>
 #include <sys/queue.h>
@@ -57,11 +58,12 @@
 static void
 irq_work_intr(void *cookie)
 {
-       struct irq_work_cpu *iwc;
+       struct irq_work_cpu *const *iwcp, *iwc;
        SIMPLEQ_HEAD(, irq_work) todo = SIMPLEQ_HEAD_INITIALIZER(todo);
        struct irq_work *iw, *next;
 
-       iwc = percpu_getref(irq_work_percpu);
+       iwcp = percpu_getref(irq_work_percpu);
+       iwc = *iwcp;
        mutex_spin_enter(&iwc->iwc_lock);
        SIMPLEQ_CONCAT(&todo, &iwc->iwc_todo);
        mutex_spin_exit(&iwc->iwc_lock);
@@ -76,8 +78,9 @@
 static void
 irq_work_cpu_init(void *ptr, void *cookie, struct cpu_info *ci)
 {
-       struct irq_work_cpu *iwc = ptr;
+       struct irq_work_cpu **iwcp = ptr, *iwc;
 
+       iwc = *iwcp = kmem_zalloc(sizeof(*iwc), KM_SLEEP);
        mutex_init(&iwc->iwc_lock, MUTEX_DEFAULT, IPL_HIGH);
        SIMPLEQ_INIT(&iwc->iwc_todo);
 }
@@ -85,10 +88,11 @@
 static void
 irq_work_cpu_fini(void *ptr, void *cookie, struct cpu_info *ci)
 {
-       struct irq_work_cpu *iwc __diagused = ptr;
+       struct irq_work_cpu **iwcp = ptr, *iwc = *iwcp;
 
        KASSERT(SIMPLEQ_EMPTY(&iwc->iwc_todo));
        mutex_destroy(&iwc->iwc_lock);
+       kmem_free(iwc, sizeof(*iwc));
 }
 
 void
@@ -120,13 +124,14 @@
 bool
 irq_work_queue(struct irq_work *iw)
 {
-       struct irq_work_cpu *iwc;
+       struct irq_work_cpu *const *iwcp, *iwc;
 
        if (atomic_swap_uint(&iw->iw_flags, IRQ_WORK_PENDING)
            & IRQ_WORK_PENDING)
                return false;
 
-       iwc = percpu_getref(irq_work_percpu);
+       iwcp = percpu_getref(irq_work_percpu);
+       iwc = *iwcp;
        mutex_spin_enter(&iwc->iwc_lock);
        SIMPLEQ_INSERT_TAIL(&iwc->iwc_todo, iw, iw_entry);
        mutex_spin_exit(&iwc->iwc_lock);