linux/drivers/gpu/drm/i915/i915_sw_fence.h
Chris Wilson 42fb60de31 drm/i915/gem: Don't leak non-persistent requests on changing engines
If we have a set of active engines marked as being non-persistent, we
lose track of those if the user replaces those engines with
I915_CONTEXT_PARAM_ENGINES. As part of our uABI contract is that
non-persistent requests are terminated if they are no longer being
tracked by the user's context (in order to prevent a lost request
causing an untracked and so unstoppable GPU hang), we need to apply the
same context cancellation upon changing engines.

v2: Track stale engines[] so we only reap at context closure.
v3: Tvrtko spotted races with closing contexts and set-engines, so add a
veneer of kill-everything paranoia to clean up after losing a race.

Fixes: a0e047156c ("drm/i915/gem: Make context persistence optional")
Testcase: igt/gem_ctx_peristence/replace
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200211144831.1011498-1-chris@chris-wilson.co.uk
2020-02-11 21:58:39 +00:00

120 lines
3.1 KiB
C

/*
* SPDX-License-Identifier: MIT
*
* i915_sw_fence.h - library routines for N:M synchronisation points
*
* Copyright (C) 2016 Intel Corporation
*/
#ifndef _I915_SW_FENCE_H_
#define _I915_SW_FENCE_H_
#include <linux/dma-fence.h>
#include <linux/gfp.h>
#include <linux/kref.h>
#include <linux/notifier.h> /* for NOTIFY_DONE */
#include <linux/wait.h>
struct completion;
struct dma_resv;
struct i915_sw_fence {
wait_queue_head_t wait;
unsigned long flags;
atomic_t pending;
int error;
};
#define I915_SW_FENCE_CHECKED_BIT 0 /* used internally for DAG checking */
#define I915_SW_FENCE_PRIVATE_BIT 1 /* available for use by owner */
#define I915_SW_FENCE_MASK (~3)
enum i915_sw_fence_notify {
FENCE_COMPLETE,
FENCE_FREE
};
typedef int (*i915_sw_fence_notify_t)(struct i915_sw_fence *,
enum i915_sw_fence_notify state);
#define __i915_sw_fence_call __aligned(4)
void __i915_sw_fence_init(struct i915_sw_fence *fence,
i915_sw_fence_notify_t fn,
const char *name,
struct lock_class_key *key);
#ifdef CONFIG_LOCKDEP
#define i915_sw_fence_init(fence, fn) \
do { \
static struct lock_class_key __key; \
\
__i915_sw_fence_init((fence), (fn), #fence, &__key); \
} while (0)
#else
#define i915_sw_fence_init(fence, fn) \
__i915_sw_fence_init((fence), (fn), NULL, NULL)
#endif
void i915_sw_fence_reinit(struct i915_sw_fence *fence);
#ifdef CONFIG_DRM_I915_SW_FENCE_DEBUG_OBJECTS
void i915_sw_fence_fini(struct i915_sw_fence *fence);
#else
static inline void i915_sw_fence_fini(struct i915_sw_fence *fence) {}
#endif
void i915_sw_fence_commit(struct i915_sw_fence *fence);
int i915_sw_fence_await_sw_fence(struct i915_sw_fence *fence,
struct i915_sw_fence *after,
wait_queue_entry_t *wq);
int i915_sw_fence_await_sw_fence_gfp(struct i915_sw_fence *fence,
struct i915_sw_fence *after,
gfp_t gfp);
struct i915_sw_dma_fence_cb {
struct dma_fence_cb base;
struct i915_sw_fence *fence;
};
int __i915_sw_fence_await_dma_fence(struct i915_sw_fence *fence,
struct dma_fence *dma,
struct i915_sw_dma_fence_cb *cb);
int i915_sw_fence_await_dma_fence(struct i915_sw_fence *fence,
struct dma_fence *dma,
unsigned long timeout,
gfp_t gfp);
int i915_sw_fence_await_reservation(struct i915_sw_fence *fence,
struct dma_resv *resv,
const struct dma_fence_ops *exclude,
bool write,
unsigned long timeout,
gfp_t gfp);
bool i915_sw_fence_await(struct i915_sw_fence *fence);
void i915_sw_fence_complete(struct i915_sw_fence *fence);
static inline bool i915_sw_fence_signaled(const struct i915_sw_fence *fence)
{
return atomic_read(&fence->pending) <= 0;
}
static inline bool i915_sw_fence_done(const struct i915_sw_fence *fence)
{
return atomic_read(&fence->pending) < 0;
}
static inline void i915_sw_fence_wait(struct i915_sw_fence *fence)
{
wait_event(fence->wait, i915_sw_fence_done(fence));
}
static inline void
i915_sw_fence_set_error_once(struct i915_sw_fence *fence, int error)
{
if (unlikely(error))
cmpxchg(&fence->error, 0, error);
}
#endif /* _I915_SW_FENCE_H_ */