mirror of
https://github.com/torvalds/linux.git
synced 2024-12-06 19:11:31 +00:00
dma-buf: add reservation_object_fences helper
Add a new helper to get a consistent set of pointers from the reservation object. While at it group all access helpers together in the header file. v2: correctly return shared_count as well Signed-off-by: Christian König <christian.koenig@amd.com> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk> Link: https://patchwork.freedesktop.org/patch/322378/?series=64837&rev=1
This commit is contained in:
parent
0e2f733add
commit
67c97fb79a
@ -199,7 +199,7 @@ static __poll_t dma_buf_poll(struct file *file, poll_table *poll)
|
||||
struct reservation_object_list *fobj;
|
||||
struct dma_fence *fence_excl;
|
||||
__poll_t events;
|
||||
unsigned shared_count, seq;
|
||||
unsigned shared_count;
|
||||
|
||||
dmabuf = file->private_data;
|
||||
if (!dmabuf || !dmabuf->resv)
|
||||
@ -213,21 +213,8 @@ static __poll_t dma_buf_poll(struct file *file, poll_table *poll)
|
||||
if (!events)
|
||||
return 0;
|
||||
|
||||
retry:
|
||||
seq = read_seqcount_begin(&resv->seq);
|
||||
rcu_read_lock();
|
||||
|
||||
fobj = rcu_dereference(resv->fence);
|
||||
if (fobj)
|
||||
shared_count = fobj->shared_count;
|
||||
else
|
||||
shared_count = 0;
|
||||
fence_excl = rcu_dereference(resv->fence_excl);
|
||||
if (read_seqcount_retry(&resv->seq, seq)) {
|
||||
rcu_read_unlock();
|
||||
goto retry;
|
||||
}
|
||||
|
||||
reservation_object_fences(resv, &fence_excl, &fobj, &shared_count);
|
||||
if (fence_excl && (!(events & EPOLLOUT) || shared_count == 0)) {
|
||||
struct dma_buf_poll_cb_t *dcb = &dmabuf->cb_excl;
|
||||
__poll_t pevents = EPOLLIN;
|
||||
@ -1157,7 +1144,6 @@ static int dma_buf_debug_show(struct seq_file *s, void *unused)
|
||||
struct reservation_object *robj;
|
||||
struct reservation_object_list *fobj;
|
||||
struct dma_fence *fence;
|
||||
unsigned seq;
|
||||
int count = 0, attach_count, shared_count, i;
|
||||
size_t size = 0;
|
||||
|
||||
@ -1188,16 +1174,9 @@ static int dma_buf_debug_show(struct seq_file *s, void *unused)
|
||||
buf_obj->name ?: "");
|
||||
|
||||
robj = buf_obj->resv;
|
||||
while (true) {
|
||||
seq = read_seqcount_begin(&robj->seq);
|
||||
rcu_read_lock();
|
||||
fobj = rcu_dereference(robj->fence);
|
||||
shared_count = fobj ? fobj->shared_count : 0;
|
||||
fence = rcu_dereference(robj->fence_excl);
|
||||
if (!read_seqcount_retry(&robj->seq, seq))
|
||||
break;
|
||||
rcu_read_unlock();
|
||||
}
|
||||
rcu_read_lock();
|
||||
reservation_object_fences(robj, &fence, &fobj, &shared_count);
|
||||
rcu_read_unlock();
|
||||
|
||||
if (fence)
|
||||
seq_printf(s, "\tExclusive fence: %s %s %ssignalled\n",
|
||||
|
@ -317,17 +317,15 @@ int reservation_object_copy_fences(struct reservation_object *dst,
|
||||
{
|
||||
struct reservation_object_list *src_list, *dst_list;
|
||||
struct dma_fence *old, *new;
|
||||
unsigned i;
|
||||
unsigned int i, shared_count;
|
||||
|
||||
reservation_object_assert_held(dst);
|
||||
|
||||
rcu_read_lock();
|
||||
src_list = rcu_dereference(src->fence);
|
||||
|
||||
retry:
|
||||
if (src_list) {
|
||||
unsigned shared_count = src_list->shared_count;
|
||||
|
||||
reservation_object_fences(src, &new, &src_list, &shared_count);
|
||||
if (shared_count) {
|
||||
rcu_read_unlock();
|
||||
|
||||
dst_list = reservation_object_list_alloc(shared_count);
|
||||
@ -335,14 +333,14 @@ retry:
|
||||
return -ENOMEM;
|
||||
|
||||
rcu_read_lock();
|
||||
src_list = rcu_dereference(src->fence);
|
||||
if (!src_list || src_list->shared_count > shared_count) {
|
||||
reservation_object_fences(src, &new, &src_list, &shared_count);
|
||||
if (!src_list || shared_count > dst_list->shared_max) {
|
||||
kfree(dst_list);
|
||||
goto retry;
|
||||
}
|
||||
|
||||
dst_list->shared_count = 0;
|
||||
for (i = 0; i < src_list->shared_count; ++i) {
|
||||
for (i = 0; i < shared_count; ++i) {
|
||||
struct dma_fence *fence;
|
||||
|
||||
fence = rcu_dereference(src_list->shared[i]);
|
||||
@ -352,7 +350,6 @@ retry:
|
||||
|
||||
if (!dma_fence_get_rcu(fence)) {
|
||||
reservation_object_list_free(dst_list);
|
||||
src_list = rcu_dereference(src->fence);
|
||||
goto retry;
|
||||
}
|
||||
|
||||
@ -367,7 +364,10 @@ retry:
|
||||
dst_list = NULL;
|
||||
}
|
||||
|
||||
new = dma_fence_get_rcu_safe(&src->fence_excl);
|
||||
if (new && !dma_fence_get_rcu(new)) {
|
||||
reservation_object_list_free(dst_list);
|
||||
goto retry;
|
||||
}
|
||||
rcu_read_unlock();
|
||||
|
||||
src_list = reservation_object_get_list(dst);
|
||||
@ -413,19 +413,18 @@ int reservation_object_get_fences_rcu(struct reservation_object *obj,
|
||||
|
||||
do {
|
||||
struct reservation_object_list *fobj;
|
||||
unsigned int i, seq;
|
||||
unsigned int i;
|
||||
size_t sz = 0;
|
||||
|
||||
shared_count = i = 0;
|
||||
i = 0;
|
||||
|
||||
rcu_read_lock();
|
||||
seq = read_seqcount_begin(&obj->seq);
|
||||
reservation_object_fences(obj, &fence_excl, &fobj,
|
||||
&shared_count);
|
||||
|
||||
fence_excl = rcu_dereference(obj->fence_excl);
|
||||
if (fence_excl && !dma_fence_get_rcu(fence_excl))
|
||||
goto unlock;
|
||||
|
||||
fobj = rcu_dereference(obj->fence);
|
||||
if (fobj)
|
||||
sz += sizeof(*shared) * fobj->shared_max;
|
||||
|
||||
@ -453,7 +452,6 @@ int reservation_object_get_fences_rcu(struct reservation_object *obj,
|
||||
break;
|
||||
}
|
||||
shared = nshared;
|
||||
shared_count = fobj ? fobj->shared_count : 0;
|
||||
for (i = 0; i < shared_count; ++i) {
|
||||
shared[i] = rcu_dereference(fobj->shared[i]);
|
||||
if (!dma_fence_get_rcu(shared[i]))
|
||||
@ -461,7 +459,7 @@ int reservation_object_get_fences_rcu(struct reservation_object *obj,
|
||||
}
|
||||
}
|
||||
|
||||
if (i != shared_count || read_seqcount_retry(&obj->seq, seq)) {
|
||||
if (i != shared_count) {
|
||||
while (i--)
|
||||
dma_fence_put(shared[i]);
|
||||
dma_fence_put(fence_excl);
|
||||
@ -505,18 +503,17 @@ long reservation_object_wait_timeout_rcu(struct reservation_object *obj,
|
||||
bool wait_all, bool intr,
|
||||
unsigned long timeout)
|
||||
{
|
||||
struct reservation_object_list *fobj;
|
||||
struct dma_fence *fence;
|
||||
unsigned seq, shared_count;
|
||||
unsigned shared_count;
|
||||
long ret = timeout ? timeout : 1;
|
||||
int i;
|
||||
|
||||
retry:
|
||||
shared_count = 0;
|
||||
seq = read_seqcount_begin(&obj->seq);
|
||||
rcu_read_lock();
|
||||
i = -1;
|
||||
|
||||
fence = rcu_dereference(obj->fence_excl);
|
||||
reservation_object_fences(obj, &fence, &fobj, &shared_count);
|
||||
if (fence && !test_bit(DMA_FENCE_FLAG_SIGNALED_BIT, &fence->flags)) {
|
||||
if (!dma_fence_get_rcu(fence))
|
||||
goto unlock_retry;
|
||||
@ -531,12 +528,6 @@ retry:
|
||||
}
|
||||
|
||||
if (wait_all) {
|
||||
struct reservation_object_list *fobj =
|
||||
rcu_dereference(obj->fence);
|
||||
|
||||
if (fobj)
|
||||
shared_count = fobj->shared_count;
|
||||
|
||||
for (i = 0; !fence && i < shared_count; ++i) {
|
||||
struct dma_fence *lfence = rcu_dereference(fobj->shared[i]);
|
||||
|
||||
@ -559,11 +550,6 @@ retry:
|
||||
|
||||
rcu_read_unlock();
|
||||
if (fence) {
|
||||
if (read_seqcount_retry(&obj->seq, seq)) {
|
||||
dma_fence_put(fence);
|
||||
goto retry;
|
||||
}
|
||||
|
||||
ret = dma_fence_wait_timeout(fence, intr, ret);
|
||||
dma_fence_put(fence);
|
||||
if (ret > 0 && wait_all && (i + 1 < shared_count))
|
||||
@ -608,24 +594,19 @@ reservation_object_test_signaled_single(struct dma_fence *passed_fence)
|
||||
bool reservation_object_test_signaled_rcu(struct reservation_object *obj,
|
||||
bool test_all)
|
||||
{
|
||||
unsigned seq, shared_count;
|
||||
struct reservation_object_list *fobj;
|
||||
struct dma_fence *fence_excl;
|
||||
unsigned shared_count;
|
||||
int ret;
|
||||
|
||||
rcu_read_lock();
|
||||
retry:
|
||||
ret = true;
|
||||
shared_count = 0;
|
||||
seq = read_seqcount_begin(&obj->seq);
|
||||
|
||||
reservation_object_fences(obj, &fence_excl, &fobj, &shared_count);
|
||||
if (test_all) {
|
||||
unsigned i;
|
||||
|
||||
struct reservation_object_list *fobj =
|
||||
rcu_dereference(obj->fence);
|
||||
|
||||
if (fobj)
|
||||
shared_count = fobj->shared_count;
|
||||
|
||||
for (i = 0; i < shared_count; ++i) {
|
||||
struct dma_fence *fence = rcu_dereference(fobj->shared[i]);
|
||||
|
||||
@ -635,23 +616,12 @@ retry:
|
||||
else if (!ret)
|
||||
break;
|
||||
}
|
||||
|
||||
if (read_seqcount_retry(&obj->seq, seq))
|
||||
goto retry;
|
||||
}
|
||||
|
||||
if (!shared_count) {
|
||||
struct dma_fence *fence_excl = rcu_dereference(obj->fence_excl);
|
||||
|
||||
if (fence_excl) {
|
||||
ret = reservation_object_test_signaled_single(
|
||||
fence_excl);
|
||||
if (ret < 0)
|
||||
goto retry;
|
||||
|
||||
if (read_seqcount_retry(&obj->seq, seq))
|
||||
goto retry;
|
||||
}
|
||||
if (!shared_count && fence_excl) {
|
||||
ret = reservation_object_test_signaled_single(fence_excl);
|
||||
if (ret < 0)
|
||||
goto retry;
|
||||
}
|
||||
|
||||
rcu_read_unlock();
|
||||
|
@ -81,6 +81,25 @@ struct reservation_object {
|
||||
#define reservation_object_assert_held(obj) \
|
||||
lockdep_assert_held(&(obj)->lock.base)
|
||||
|
||||
/**
|
||||
* reservation_object_get_excl - get the reservation object's
|
||||
* exclusive fence, with update-side lock held
|
||||
* @obj: the reservation object
|
||||
*
|
||||
* Returns the exclusive fence (if any). Does NOT take a
|
||||
* reference. Writers must hold obj->lock, readers may only
|
||||
* hold a RCU read side lock.
|
||||
*
|
||||
* RETURNS
|
||||
* The exclusive fence or NULL
|
||||
*/
|
||||
static inline struct dma_fence *
|
||||
reservation_object_get_excl(struct reservation_object *obj)
|
||||
{
|
||||
return rcu_dereference_protected(obj->fence_excl,
|
||||
reservation_object_held(obj));
|
||||
}
|
||||
|
||||
/**
|
||||
* reservation_object_get_list - get the reservation object's
|
||||
* shared fence list, with update-side lock held
|
||||
@ -96,6 +115,57 @@ reservation_object_get_list(struct reservation_object *obj)
|
||||
reservation_object_held(obj));
|
||||
}
|
||||
|
||||
/**
|
||||
* reservation_object_fences - read consistent fence pointers
|
||||
* @obj: reservation object where we get the fences from
|
||||
* @excl: pointer for the exclusive fence
|
||||
* @list: pointer for the shared fence list
|
||||
*
|
||||
* Make sure we have a consisten exclusive fence and shared fence list.
|
||||
* Must be called with rcu read side lock held.
|
||||
*/
|
||||
static inline void
|
||||
reservation_object_fences(struct reservation_object *obj,
|
||||
struct dma_fence **excl,
|
||||
struct reservation_object_list **list,
|
||||
u32 *shared_count)
|
||||
{
|
||||
unsigned int seq;
|
||||
|
||||
do {
|
||||
seq = read_seqcount_begin(&obj->seq);
|
||||
*excl = rcu_dereference(obj->fence_excl);
|
||||
*list = rcu_dereference(obj->fence);
|
||||
*shared_count = *list ? (*list)->shared_count : 0;
|
||||
} while (read_seqcount_retry(&obj->seq, seq));
|
||||
}
|
||||
|
||||
/**
|
||||
* reservation_object_get_excl_rcu - get the reservation object's
|
||||
* exclusive fence, without lock held.
|
||||
* @obj: the reservation object
|
||||
*
|
||||
* If there is an exclusive fence, this atomically increments it's
|
||||
* reference count and returns it.
|
||||
*
|
||||
* RETURNS
|
||||
* The exclusive fence or NULL if none
|
||||
*/
|
||||
static inline struct dma_fence *
|
||||
reservation_object_get_excl_rcu(struct reservation_object *obj)
|
||||
{
|
||||
struct dma_fence *fence;
|
||||
|
||||
if (!rcu_access_pointer(obj->fence_excl))
|
||||
return NULL;
|
||||
|
||||
rcu_read_lock();
|
||||
fence = dma_fence_get_rcu_safe(&obj->fence_excl);
|
||||
rcu_read_unlock();
|
||||
|
||||
return fence;
|
||||
}
|
||||
|
||||
/**
|
||||
* reservation_object_lock - lock the reservation object
|
||||
* @obj: the reservation object
|
||||
@ -239,51 +309,6 @@ reservation_object_unlock(struct reservation_object *obj)
|
||||
ww_mutex_unlock(&obj->lock);
|
||||
}
|
||||
|
||||
/**
|
||||
* reservation_object_get_excl - get the reservation object's
|
||||
* exclusive fence, with update-side lock held
|
||||
* @obj: the reservation object
|
||||
*
|
||||
* Returns the exclusive fence (if any). Does NOT take a
|
||||
* reference. Writers must hold obj->lock, readers may only
|
||||
* hold a RCU read side lock.
|
||||
*
|
||||
* RETURNS
|
||||
* The exclusive fence or NULL
|
||||
*/
|
||||
static inline struct dma_fence *
|
||||
reservation_object_get_excl(struct reservation_object *obj)
|
||||
{
|
||||
return rcu_dereference_protected(obj->fence_excl,
|
||||
reservation_object_held(obj));
|
||||
}
|
||||
|
||||
/**
|
||||
* reservation_object_get_excl_rcu - get the reservation object's
|
||||
* exclusive fence, without lock held.
|
||||
* @obj: the reservation object
|
||||
*
|
||||
* If there is an exclusive fence, this atomically increments it's
|
||||
* reference count and returns it.
|
||||
*
|
||||
* RETURNS
|
||||
* The exclusive fence or NULL if none
|
||||
*/
|
||||
static inline struct dma_fence *
|
||||
reservation_object_get_excl_rcu(struct reservation_object *obj)
|
||||
{
|
||||
struct dma_fence *fence;
|
||||
|
||||
if (!rcu_access_pointer(obj->fence_excl))
|
||||
return NULL;
|
||||
|
||||
rcu_read_lock();
|
||||
fence = dma_fence_get_rcu_safe(&obj->fence_excl);
|
||||
rcu_read_unlock();
|
||||
|
||||
return fence;
|
||||
}
|
||||
|
||||
void reservation_object_init(struct reservation_object *obj);
|
||||
void reservation_object_fini(struct reservation_object *obj);
|
||||
int reservation_object_reserve_shared(struct reservation_object *obj,
|
||||
|
Loading…
Reference in New Issue
Block a user