Module Name: src
Committed By: riastradh
Date: Mon Aug 27 14:13:16 UTC 2018
Modified Files:
src/sys/external/bsd/drm2/linux: linux_fence.c
Log Message:
Lotsa kasserts about referencedness of frences.
To generate a diff of this commit:
cvs rdiff -u -r1.5 -r1.6 src/sys/external/bsd/drm2/linux/linux_fence.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/external/bsd/drm2/linux/linux_fence.c
diff -u src/sys/external/bsd/drm2/linux/linux_fence.c:1.5 src/sys/external/bsd/drm2/linux/linux_fence.c:1.6
--- src/sys/external/bsd/drm2/linux/linux_fence.c:1.5 Mon Aug 27 14:01:01 2018
+++ src/sys/external/bsd/drm2/linux/linux_fence.c Mon Aug 27 14:13:16 2018
@@ -1,4 +1,4 @@
-/* $NetBSD: linux_fence.c,v 1.5 2018/08/27 14:01:01 riastradh Exp $ */
+/* $NetBSD: linux_fence.c,v 1.6 2018/08/27 14:13:16 riastradh Exp $ */
/*-
* Copyright (c) 2018 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: linux_fence.c,v 1.5 2018/08/27 14:01:01 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: linux_fence.c,v 1.6 2018/08/27 14:13:16 riastradh Exp $");
#include <sys/atomic.h>
#include <sys/condvar.h>
@@ -44,6 +44,19 @@ __KERNEL_RCSID(0, "$NetBSD: linux_fence.
#include <linux/spinlock.h>
/*
+ * fence_referenced_p(fence)
+ *
+ * True if fence has a positive reference count. True after
+ * fence_init; after the last fence_put, this becomes false.
+ */
+static inline bool
+fence_referenced_p(struct fence *fence)
+{
+
+ return kref_referenced_p(&fence->refcount);
+}
+
+/*
* fence_init(fence, ops, lock, context, seqno)
*
* Initialize fence. Caller should call fence_destroy when done,
@@ -74,6 +87,8 @@ void
fence_destroy(struct fence *fence)
{
+ KASSERT(!fence_referenced_p(fence));
+
KASSERT(TAILQ_EMPTY(&fence->f_callbacks));
cv_destroy(&fence->f_cv);
}
@@ -83,6 +98,8 @@ fence_free_cb(struct rcu_head *rcu)
{
struct fence *fence = container_of(rcu, struct fence, f_rcu);
+ KASSERT(!fence_referenced_p(fence));
+
fence_destroy(fence);
kfree(fence);
}
@@ -103,6 +120,8 @@ void
fence_free(struct fence *fence)
{
+ KASSERT(!fence_referenced_p(fence));
+
call_rcu(&fence->f_rcu, &fence_free_cb);
}
@@ -176,6 +195,8 @@ fence_release(struct kref *refcount)
{
struct fence *fence = container_of(refcount, struct fence, refcount);
+ KASSERT(!fence_referenced_p(fence));
+
if (fence->ops->release)
(*fence->ops->release)(fence);
else
@@ -192,6 +213,7 @@ void
fence_put(struct fence *fence)
{
+ KASSERT(fence_referenced_p(fence));
kref_put(&fence->refcount, &fence_release);
}
@@ -210,6 +232,7 @@ static int
fence_ensure_signal_enabled(struct fence *fence)
{
+ KASSERT(fence_referenced_p(fence));
KASSERT(spin_is_locked(fence->lock));
/* If the fence was already signalled, fail with -ENOENT. */
@@ -251,6 +274,8 @@ fence_add_callback(struct fence *fence,
{
int ret;
+ KASSERT(fence_referenced_p(fence));
+
/* Optimistically try to skip the lock if it's already signalled. */
if (fence->flags & (1u << FENCE_FLAG_SIGNALED_BIT)) {
ret = -ENOENT;
@@ -288,6 +313,8 @@ fence_remove_callback(struct fence *fenc
{
bool onqueue;
+ KASSERT(fence_referenced_p(fence));
+
spin_lock(fence->lock);
onqueue = fcb->fcb_onqueue;
if (onqueue) {
@@ -311,6 +338,8 @@ void
fence_enable_sw_signaling(struct fence *fence)
{
+ KASSERT(fence_referenced_p(fence));
+
spin_lock(fence->lock);
(void)fence_ensure_signal_enabled(fence);
spin_unlock(fence->lock);
@@ -330,6 +359,8 @@ fence_is_signaled(struct fence *fence)
{
bool signaled;
+ KASSERT(fence_referenced_p(fence));
+
spin_lock(fence->lock);
signaled = fence_is_signaled_locked(fence);
spin_unlock(fence->lock);
@@ -347,6 +378,7 @@ bool
fence_is_signaled_locked(struct fence *fence)
{
+ KASSERT(fence_referenced_p(fence));
KASSERT(spin_is_locked(fence->lock));
/* Check whether we already set the signalled bit. */
@@ -383,6 +415,8 @@ fence_signal(struct fence *fence)
{
int ret;
+ KASSERT(fence_referenced_p(fence));
+
spin_lock(fence->lock);
ret = fence_signal_locked(fence);
spin_unlock(fence->lock);
@@ -401,6 +435,7 @@ fence_signal_locked(struct fence *fence)
{
struct fence_cb *fcb, *next;
+ KASSERT(fence_referenced_p(fence));
KASSERT(spin_is_locked(fence->lock));
/* If it's been signalled, fail; otherwise set the signalled bit. */
@@ -435,6 +470,8 @@ wait_any_cb(struct fence *fence, struct
{
struct wait_any *cb = container_of(fcb, struct wait_any, fcb);
+ KASSERT(fence_referenced_p(fence));
+
mutex_enter(&cb->common->lock);
cb->common->done = true;
cv_broadcast(&cb->common->cv);
@@ -472,6 +509,7 @@ fence_wait_any_timeout(struct fence **fe
/* Add a callback to each of the fences, or stop here if we can't. */
for (i = 0; i < nfences; i++) {
cb[i].common = &common;
+ KASSERT(fence_referenced_p(fences[i]));
ret = fence_add_callback(fences[i], &cb[i].fcb, &wait_any_cb);
if (ret)
goto out1;
@@ -559,8 +597,10 @@ long
fence_wait_timeout(struct fence *fence, bool intr, long timeout)
{
+ KASSERT(fence_referenced_p(fence));
KASSERT(timeout >= 0);
KASSERT(timeout < MAX_SCHEDULE_TIMEOUT);
+
return (*fence->ops->wait)(fence, intr, timeout);
}
@@ -577,6 +617,8 @@ fence_wait(struct fence *fence, bool int
{
long ret;
+ KASSERT(fence_referenced_p(fence));
+
ret = (*fence->ops->wait)(fence, intr, MAX_SCHEDULE_TIMEOUT);
KASSERT(ret != 0);
@@ -600,6 +642,7 @@ fence_default_wait(struct fence *fence,
kmutex_t *lock = &fence->lock->sl_lock;
long ret = 0;
+ KASSERT(fence_referenced_p(fence));
KASSERT(timeout >= 0);
KASSERT(timeout <= MAX_SCHEDULE_TIMEOUT);
