mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-06 02:36:40 +07:00
847b19a39e
When specified timeout is zero for fence_wait_timeout, just check if the fence is signaled or not without wait. Signed-off-by: Jammy Zhou <Jammy.Zhou@amd.com> Reviewed-by: Christian König <christian.koenig@amd.com> Reviewed-By: Maarten Lankhorst <maarten.lankhorst@canonical.com> Signed-off-by: Sumit Semwal <sumit.semwal@linaro.org>
435 lines
12 KiB
C
435 lines
12 KiB
C
/*
|
|
* Fence mechanism for dma-buf and to allow for asynchronous dma access
|
|
*
|
|
* Copyright (C) 2012 Canonical Ltd
|
|
* Copyright (C) 2012 Texas Instruments
|
|
*
|
|
* Authors:
|
|
* Rob Clark <robdclark@gmail.com>
|
|
* Maarten Lankhorst <maarten.lankhorst@canonical.com>
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify it
|
|
* under the terms of the GNU General Public License version 2 as published by
|
|
* the Free Software Foundation.
|
|
*
|
|
* This program is distributed in the hope that it will be useful, but WITHOUT
|
|
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
|
|
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
|
|
* more details.
|
|
*/
|
|
|
|
#include <linux/slab.h>
|
|
#include <linux/export.h>
|
|
#include <linux/atomic.h>
|
|
#include <linux/fence.h>
|
|
|
|
#define CREATE_TRACE_POINTS
|
|
#include <trace/events/fence.h>
|
|
|
|
EXPORT_TRACEPOINT_SYMBOL(fence_annotate_wait_on);
|
|
EXPORT_TRACEPOINT_SYMBOL(fence_emit);
|
|
|
|
/*
|
|
* fence context counter: each execution context should have its own
|
|
* fence context, this allows checking if fences belong to the same
|
|
* context or not. One device can have multiple separate contexts,
|
|
* and they're used if some engine can run independently of another.
|
|
*/
|
|
static atomic_t fence_context_counter = ATOMIC_INIT(0);
|
|
|
|
/**
|
|
* fence_context_alloc - allocate an array of fence contexts
|
|
* @num: [in] amount of contexts to allocate
|
|
*
|
|
* This function will return the first index of the number of fences allocated.
|
|
* The fence context is used for setting fence->context to a unique number.
|
|
*/
|
|
unsigned fence_context_alloc(unsigned num)
|
|
{
|
|
BUG_ON(!num);
|
|
return atomic_add_return(num, &fence_context_counter) - num;
|
|
}
|
|
EXPORT_SYMBOL(fence_context_alloc);
|
|
|
|
/**
|
|
* fence_signal_locked - signal completion of a fence
|
|
* @fence: the fence to signal
|
|
*
|
|
* Signal completion for software callbacks on a fence, this will unblock
|
|
* fence_wait() calls and run all the callbacks added with
|
|
* fence_add_callback(). Can be called multiple times, but since a fence
|
|
* can only go from unsignaled to signaled state, it will only be effective
|
|
* the first time.
|
|
*
|
|
* Unlike fence_signal, this function must be called with fence->lock held.
|
|
*/
|
|
int fence_signal_locked(struct fence *fence)
|
|
{
|
|
struct fence_cb *cur, *tmp;
|
|
int ret = 0;
|
|
|
|
if (WARN_ON(!fence))
|
|
return -EINVAL;
|
|
|
|
if (!ktime_to_ns(fence->timestamp)) {
|
|
fence->timestamp = ktime_get();
|
|
smp_mb__before_atomic();
|
|
}
|
|
|
|
if (test_and_set_bit(FENCE_FLAG_SIGNALED_BIT, &fence->flags)) {
|
|
ret = -EINVAL;
|
|
|
|
/*
|
|
* we might have raced with the unlocked fence_signal,
|
|
* still run through all callbacks
|
|
*/
|
|
} else
|
|
trace_fence_signaled(fence);
|
|
|
|
list_for_each_entry_safe(cur, tmp, &fence->cb_list, node) {
|
|
list_del_init(&cur->node);
|
|
cur->func(fence, cur);
|
|
}
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL(fence_signal_locked);
|
|
|
|
/**
|
|
* fence_signal - signal completion of a fence
|
|
* @fence: the fence to signal
|
|
*
|
|
* Signal completion for software callbacks on a fence, this will unblock
|
|
* fence_wait() calls and run all the callbacks added with
|
|
* fence_add_callback(). Can be called multiple times, but since a fence
|
|
* can only go from unsignaled to signaled state, it will only be effective
|
|
* the first time.
|
|
*/
|
|
int fence_signal(struct fence *fence)
|
|
{
|
|
unsigned long flags;
|
|
|
|
if (!fence)
|
|
return -EINVAL;
|
|
|
|
if (!ktime_to_ns(fence->timestamp)) {
|
|
fence->timestamp = ktime_get();
|
|
smp_mb__before_atomic();
|
|
}
|
|
|
|
if (test_and_set_bit(FENCE_FLAG_SIGNALED_BIT, &fence->flags))
|
|
return -EINVAL;
|
|
|
|
trace_fence_signaled(fence);
|
|
|
|
if (test_bit(FENCE_FLAG_ENABLE_SIGNAL_BIT, &fence->flags)) {
|
|
struct fence_cb *cur, *tmp;
|
|
|
|
spin_lock_irqsave(fence->lock, flags);
|
|
list_for_each_entry_safe(cur, tmp, &fence->cb_list, node) {
|
|
list_del_init(&cur->node);
|
|
cur->func(fence, cur);
|
|
}
|
|
spin_unlock_irqrestore(fence->lock, flags);
|
|
}
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL(fence_signal);
|
|
|
|
/**
|
|
* fence_wait_timeout - sleep until the fence gets signaled
|
|
* or until timeout elapses
|
|
* @fence: [in] the fence to wait on
|
|
* @intr: [in] if true, do an interruptible wait
|
|
* @timeout: [in] timeout value in jiffies, or MAX_SCHEDULE_TIMEOUT
|
|
*
|
|
* Returns -ERESTARTSYS if interrupted, 0 if the wait timed out, or the
|
|
* remaining timeout in jiffies on success. Other error values may be
|
|
* returned on custom implementations.
|
|
*
|
|
* Performs a synchronous wait on this fence. It is assumed the caller
|
|
* directly or indirectly (buf-mgr between reservation and committing)
|
|
* holds a reference to the fence, otherwise the fence might be
|
|
* freed before return, resulting in undefined behavior.
|
|
*/
|
|
signed long
|
|
fence_wait_timeout(struct fence *fence, bool intr, signed long timeout)
|
|
{
|
|
signed long ret;
|
|
|
|
if (WARN_ON(timeout < 0))
|
|
return -EINVAL;
|
|
|
|
if (timeout == 0)
|
|
return fence_is_signaled(fence);
|
|
|
|
trace_fence_wait_start(fence);
|
|
ret = fence->ops->wait(fence, intr, timeout);
|
|
trace_fence_wait_end(fence);
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL(fence_wait_timeout);
|
|
|
|
void fence_release(struct kref *kref)
|
|
{
|
|
struct fence *fence =
|
|
container_of(kref, struct fence, refcount);
|
|
|
|
trace_fence_destroy(fence);
|
|
|
|
BUG_ON(!list_empty(&fence->cb_list));
|
|
|
|
if (fence->ops->release)
|
|
fence->ops->release(fence);
|
|
else
|
|
fence_free(fence);
|
|
}
|
|
EXPORT_SYMBOL(fence_release);
|
|
|
|
void fence_free(struct fence *fence)
|
|
{
|
|
kfree_rcu(fence, rcu);
|
|
}
|
|
EXPORT_SYMBOL(fence_free);
|
|
|
|
/**
|
|
* fence_enable_sw_signaling - enable signaling on fence
|
|
* @fence: [in] the fence to enable
|
|
*
|
|
* this will request for sw signaling to be enabled, to make the fence
|
|
* complete as soon as possible
|
|
*/
|
|
void fence_enable_sw_signaling(struct fence *fence)
|
|
{
|
|
unsigned long flags;
|
|
|
|
if (!test_and_set_bit(FENCE_FLAG_ENABLE_SIGNAL_BIT, &fence->flags) &&
|
|
!test_bit(FENCE_FLAG_SIGNALED_BIT, &fence->flags)) {
|
|
trace_fence_enable_signal(fence);
|
|
|
|
spin_lock_irqsave(fence->lock, flags);
|
|
|
|
if (!fence->ops->enable_signaling(fence))
|
|
fence_signal_locked(fence);
|
|
|
|
spin_unlock_irqrestore(fence->lock, flags);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(fence_enable_sw_signaling);
|
|
|
|
/**
|
|
* fence_add_callback - add a callback to be called when the fence
|
|
* is signaled
|
|
* @fence: [in] the fence to wait on
|
|
* @cb: [in] the callback to register
|
|
* @func: [in] the function to call
|
|
*
|
|
* cb will be initialized by fence_add_callback, no initialization
|
|
* by the caller is required. Any number of callbacks can be registered
|
|
* to a fence, but a callback can only be registered to one fence at a time.
|
|
*
|
|
* Note that the callback can be called from an atomic context. If
|
|
* fence is already signaled, this function will return -ENOENT (and
|
|
* *not* call the callback)
|
|
*
|
|
* Add a software callback to the fence. Same restrictions apply to
|
|
* refcount as it does to fence_wait, however the caller doesn't need to
|
|
* keep a refcount to fence afterwards: when software access is enabled,
|
|
* the creator of the fence is required to keep the fence alive until
|
|
* after it signals with fence_signal. The callback itself can be called
|
|
* from irq context.
|
|
*
|
|
*/
|
|
int fence_add_callback(struct fence *fence, struct fence_cb *cb,
|
|
fence_func_t func)
|
|
{
|
|
unsigned long flags;
|
|
int ret = 0;
|
|
bool was_set;
|
|
|
|
if (WARN_ON(!fence || !func))
|
|
return -EINVAL;
|
|
|
|
if (test_bit(FENCE_FLAG_SIGNALED_BIT, &fence->flags)) {
|
|
INIT_LIST_HEAD(&cb->node);
|
|
return -ENOENT;
|
|
}
|
|
|
|
spin_lock_irqsave(fence->lock, flags);
|
|
|
|
was_set = test_and_set_bit(FENCE_FLAG_ENABLE_SIGNAL_BIT, &fence->flags);
|
|
|
|
if (test_bit(FENCE_FLAG_SIGNALED_BIT, &fence->flags))
|
|
ret = -ENOENT;
|
|
else if (!was_set) {
|
|
trace_fence_enable_signal(fence);
|
|
|
|
if (!fence->ops->enable_signaling(fence)) {
|
|
fence_signal_locked(fence);
|
|
ret = -ENOENT;
|
|
}
|
|
}
|
|
|
|
if (!ret) {
|
|
cb->func = func;
|
|
list_add_tail(&cb->node, &fence->cb_list);
|
|
} else
|
|
INIT_LIST_HEAD(&cb->node);
|
|
spin_unlock_irqrestore(fence->lock, flags);
|
|
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL(fence_add_callback);
|
|
|
|
/**
|
|
* fence_remove_callback - remove a callback from the signaling list
|
|
* @fence: [in] the fence to wait on
|
|
* @cb: [in] the callback to remove
|
|
*
|
|
* Remove a previously queued callback from the fence. This function returns
|
|
* true if the callback is successfully removed, or false if the fence has
|
|
* already been signaled.
|
|
*
|
|
* *WARNING*:
|
|
* Cancelling a callback should only be done if you really know what you're
|
|
* doing, since deadlocks and race conditions could occur all too easily. For
|
|
* this reason, it should only ever be done on hardware lockup recovery,
|
|
* with a reference held to the fence.
|
|
*/
|
|
bool
|
|
fence_remove_callback(struct fence *fence, struct fence_cb *cb)
|
|
{
|
|
unsigned long flags;
|
|
bool ret;
|
|
|
|
spin_lock_irqsave(fence->lock, flags);
|
|
|
|
ret = !list_empty(&cb->node);
|
|
if (ret)
|
|
list_del_init(&cb->node);
|
|
|
|
spin_unlock_irqrestore(fence->lock, flags);
|
|
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL(fence_remove_callback);
|
|
|
|
struct default_wait_cb {
|
|
struct fence_cb base;
|
|
struct task_struct *task;
|
|
};
|
|
|
|
static void
|
|
fence_default_wait_cb(struct fence *fence, struct fence_cb *cb)
|
|
{
|
|
struct default_wait_cb *wait =
|
|
container_of(cb, struct default_wait_cb, base);
|
|
|
|
wake_up_state(wait->task, TASK_NORMAL);
|
|
}
|
|
|
|
/**
|
|
* fence_default_wait - default sleep until the fence gets signaled
|
|
* or until timeout elapses
|
|
* @fence: [in] the fence to wait on
|
|
* @intr: [in] if true, do an interruptible wait
|
|
* @timeout: [in] timeout value in jiffies, or MAX_SCHEDULE_TIMEOUT
|
|
*
|
|
* Returns -ERESTARTSYS if interrupted, 0 if the wait timed out, or the
|
|
* remaining timeout in jiffies on success.
|
|
*/
|
|
signed long
|
|
fence_default_wait(struct fence *fence, bool intr, signed long timeout)
|
|
{
|
|
struct default_wait_cb cb;
|
|
unsigned long flags;
|
|
signed long ret = timeout;
|
|
bool was_set;
|
|
|
|
if (test_bit(FENCE_FLAG_SIGNALED_BIT, &fence->flags))
|
|
return timeout;
|
|
|
|
spin_lock_irqsave(fence->lock, flags);
|
|
|
|
if (intr && signal_pending(current)) {
|
|
ret = -ERESTARTSYS;
|
|
goto out;
|
|
}
|
|
|
|
was_set = test_and_set_bit(FENCE_FLAG_ENABLE_SIGNAL_BIT, &fence->flags);
|
|
|
|
if (test_bit(FENCE_FLAG_SIGNALED_BIT, &fence->flags))
|
|
goto out;
|
|
|
|
if (!was_set) {
|
|
trace_fence_enable_signal(fence);
|
|
|
|
if (!fence->ops->enable_signaling(fence)) {
|
|
fence_signal_locked(fence);
|
|
goto out;
|
|
}
|
|
}
|
|
|
|
cb.base.func = fence_default_wait_cb;
|
|
cb.task = current;
|
|
list_add(&cb.base.node, &fence->cb_list);
|
|
|
|
while (!test_bit(FENCE_FLAG_SIGNALED_BIT, &fence->flags) && ret > 0) {
|
|
if (intr)
|
|
__set_current_state(TASK_INTERRUPTIBLE);
|
|
else
|
|
__set_current_state(TASK_UNINTERRUPTIBLE);
|
|
spin_unlock_irqrestore(fence->lock, flags);
|
|
|
|
ret = schedule_timeout(ret);
|
|
|
|
spin_lock_irqsave(fence->lock, flags);
|
|
if (ret > 0 && intr && signal_pending(current))
|
|
ret = -ERESTARTSYS;
|
|
}
|
|
|
|
if (!list_empty(&cb.base.node))
|
|
list_del(&cb.base.node);
|
|
__set_current_state(TASK_RUNNING);
|
|
|
|
out:
|
|
spin_unlock_irqrestore(fence->lock, flags);
|
|
return ret;
|
|
}
|
|
EXPORT_SYMBOL(fence_default_wait);
|
|
|
|
/**
|
|
* fence_init - Initialize a custom fence.
|
|
* @fence: [in] the fence to initialize
|
|
* @ops: [in] the fence_ops for operations on this fence
|
|
* @lock: [in] the irqsafe spinlock to use for locking this fence
|
|
* @context: [in] the execution context this fence is run on
|
|
* @seqno: [in] a linear increasing sequence number for this context
|
|
*
|
|
* Initializes an allocated fence, the caller doesn't have to keep its
|
|
* refcount after committing with this fence, but it will need to hold a
|
|
* refcount again if fence_ops.enable_signaling gets called. This can
|
|
* be used for other implementing other types of fence.
|
|
*
|
|
* context and seqno are used for easy comparison between fences, allowing
|
|
* to check which fence is later by simply using fence_later.
|
|
*/
|
|
void
|
|
fence_init(struct fence *fence, const struct fence_ops *ops,
|
|
spinlock_t *lock, unsigned context, unsigned seqno)
|
|
{
|
|
BUG_ON(!lock);
|
|
BUG_ON(!ops || !ops->wait || !ops->enable_signaling ||
|
|
!ops->get_driver_name || !ops->get_timeline_name);
|
|
|
|
kref_init(&fence->refcount);
|
|
fence->ops = ops;
|
|
INIT_LIST_HEAD(&fence->cb_list);
|
|
fence->lock = lock;
|
|
fence->context = context;
|
|
fence->seqno = seqno;
|
|
fence->flags = 0UL;
|
|
|
|
trace_fence_init(fence);
|
|
}
|
|
EXPORT_SYMBOL(fence_init);
|