LXR linux/drivers/gpu/drm/i915/i915_sw_fence

   1/* SPDX-License-Identifier: MIT */
   2
   3/*
   4 * Copyright © 2019 Intel Corporation
   5 */
   6
   7#ifndef I915_SW_FENCE_WORK_H
   8#define I915_SW_FENCE_WORK_H
   9
  10#include <linux/dma-fence.h>
  11#include <linux/spinlock.h>
  12#include <linux/workqueue.h>
  13
  14#include "i915_sw_fence.h"
  15
  16struct dma_fence_work;
  17
  18struct dma_fence_work_ops {
  19        const char *name;
  20        void (*work)(struct dma_fence_work *f);
  21        void (*release)(struct dma_fence_work *f);
  22};
  23
  24struct dma_fence_work {
  25        struct dma_fence dma;
  26        spinlock_t lock;
  27
  28        struct i915_sw_fence chain;
  29        struct i915_sw_dma_fence_cb cb;
  30
  31        struct work_struct work;
  32        const struct dma_fence_work_ops *ops;
  33};
  34
  35enum {
  36        DMA_FENCE_WORK_IMM = DMA_FENCE_FLAG_USER_BITS,
  37};
  38
  39void dma_fence_work_init(struct dma_fence_work *f,
  40                         const struct dma_fence_work_ops *ops);
  41int dma_fence_work_chain(struct dma_fence_work *f, struct dma_fence *signal);
  42
  43static inline void dma_fence_work_commit(struct dma_fence_work *f)
  44{
  45        i915_sw_fence_commit(&f->chain);
  46}
  47
  48/**
  49 * dma_fence_work_commit_imm: Commit the fence, and if possible execute locally.
  50 * @f: the fenced worker
  51 *
  52 * Instead of always scheduling a worker to execute the callback (see
  53 * dma_fence_work_commit()), we try to execute the callback immediately in
  54 * the local context. It is required that the fence be committed before it
  55 * is published, and that no other threads try to tamper with the number
  56 * of asynchronous waits on the fence (or else the callback will be
  57 * executed in the wrong context, i.e. not the callers).
  58 */
  59static inline void dma_fence_work_commit_imm(struct dma_fence_work *f)
  60{
  61        if (atomic_read(&f->chain.pending) <= 1)
  62                __set_bit(DMA_FENCE_WORK_IMM, &f->dma.flags);
  63
  64        dma_fence_work_commit(f);
  65}
  66
  67#endif /* I915_SW_FENCE_WORK_H */
  68