[PATCH 1/6] drm/i915: Update dma_fence_work

Thomas Hellström
2021-10-08T13:35:50Z

Move the release callback to after fence signaling to align with
what's done for upcoming VM_BIND user-fence signaling.

Finally call the work callback regardless of whether we have a fence
error or not and update the existing callbacks accordingly. We will
need this to intercept the error for failsafe migration.

Signed-off-by: Thomas Hellström <thomas.hellstrom@linux.intel.com>
---
drivers/gpu/drm/i915/gem/i915_gem_clflush.c | 5 +++
drivers/gpu/drm/i915/i915_sw_fence_work.c | 36 ++++++++++-----------
drivers/gpu/drm/i915/i915_sw_fence_work.h | 1 +
drivers/gpu/drm/i915/i915_vma.c | 12 +++++--
4 files changed, 33 insertions(+), 21 deletions(-)

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_clflush.c b/drivers/gpu/drm/i915/gem/i915_gem_clflush.c
index f0435c6feb68..2143ebaf5b6f 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_clflush.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_clflush.c
@@ -28,6 +28,11 @@ static void clflush_work(struct dma_fence_work *base)
{
struct clflush *clflush = container_of(base, typeof(*clflush), base);

+ if (base->error) {
+ dma_fence_set_error(&base->dma, base->error);
+ return;
+ }
+
__do_clflush(clflush->obj);
}

diff --git a/drivers/gpu/drm/i915/i915_sw_fence_work.c b/drivers/gpu/drm/i915/i915_sw_fence_work.c
index 5b33ef23d54c..5b55cddafc9b 100644
--- a/drivers/gpu/drm/i915/i915_sw_fence_work.c
+++ b/drivers/gpu/drm/i915/i915_sw_fence_work.c
@@ -6,21 +6,24 @@

#include "i915_sw_fence_work.h"

-static void fence_complete(struct dma_fence_work *f)
+static void dma_fence_work_complete(struct dma_fence_work *f)
{
+ dma_fence_signal(&f->dma);
+
if (f->ops->release)
f->ops->release(f);
- dma_fence_signal(&f->dma);
+
+ dma_fence_put(&f->dma);
}

-static void fence_work(struct work_struct *work)
+static void dma_fence_work_work(struct work_struct *work)
{
struct dma_fence_work *f = container_of(work, typeof(*f), work);

- f->ops->work(f);
+ if (f->ops->work)
+ f->ops->work(f);

- fence_complete(f);
- dma_fence_put(&f->dma);
+ dma_fence_work_complete(f);
}

static int __i915_sw_fence_call
@@ -31,17 +34,13 @@ fence_notify(struct i915_sw_fence *fence, enum i915_sw_fence_notify state)
switch (state) {
case FENCE_COMPLETE:
if (fence->error)
- dma_fence_set_error(&f->dma, fence->error);
-
- if (!f->dma.error) {
- dma_fence_get(&f->dma);
- if (test_bit(DMA_FENCE_WORK_IMM, &f->dma.flags))
- fence_work(&f->work);
- else
- queue_work(system_unbound_wq, &f->work);
- } else {
- fence_complete(f);
- }
+ cmpxchg(&f->error, 0, fence->error);
+
+ dma_fence_get(&f->dma);
+ if (test_bit(DMA_FENCE_WORK_IMM, &f->dma.flags))
+ dma_fence_work_work(&f->work);
+ else
+ queue_work(system_unbound_wq, &f->work);
break;

case FENCE_FREE:
@@ -84,10 +83,11 @@ void dma_fence_work_init(struct dma_fence_work *f,
const struct dma_fence_work_ops *ops)
{
f->ops = ops;
+ f->error = 0;
spin_lock_init(&f->lock);
dma_fence_init(&f->dma, &fence_ops, &f->lock, 0, 0);
i915_sw_fence_init(&f->chain, fence_notify);
- INIT_WORK(&f->work, fence_work);
+ INIT_WORK(&f->work, dma_fence_work_work);
}

int dma_fence_work_chain(struct dma_fence_work *f, struct dma_fence *signal)
diff --git a/drivers/gpu/drm/i915/i915_sw_fence_work.h b/drivers/gpu/drm/i915/i915_sw_fence_work.h
index d56806918d13..caa59fb5252b 100644
--- a/drivers/gpu/drm/i915/i915_sw_fence_work.h
+++ b/drivers/gpu/drm/i915/i915_sw_fence_work.h
@@ -24,6 +24,7 @@ struct dma_fence_work_ops {
struct dma_fence_work {
struct dma_fence dma;
spinlock_t lock;
+ int error;

struct i915_sw_fence chain;
struct i915_sw_dma_fence_cb cb;
diff --git a/drivers/gpu/drm/i915/i915_vma.c b/drivers/gpu/drm/i915/i915_vma.c
index 4b7fc4647e46..5123ac28ad9a 100644
--- a/drivers/gpu/drm/i915/i915_vma.c
+++ b/drivers/gpu/drm/i915/i915_vma.c
@@ -301,6 +301,11 @@ static void __vma_bind(struct dma_fence_work *work)
struct i915_vma_work *vw = container_of(work, typeof(*vw), base);
struct i915_vma *vma = vw->vma;

+ if (work->error) {
+ dma_fence_set_error(&work->dma, work->error);
+ return;
+ }
+
vma->ops->bind_vma(vw->vm, &vw->stash,
vma, vw->cache_level, vw->flags);
}
@@ -333,7 +338,7 @@ struct i915_vma_work *i915_vma_work(void)
return NULL;

dma_fence_work_init(&vw->base, &bind_ops);
- vw->base.dma.error = -EAGAIN; /* disable the worker by default */
+ vw->base.error = -EAGAIN; /* disable the worker by default */

return vw;
}
@@ -416,6 +421,9 @@ int i915_vma_bind(struct i915_vma *vma,
* part of the obj->resv->excl_fence as it only affects
* execution and not content or object's backing store lifetime.
*/
+
+ work->base.error = 0; /* enable the queue_work() */
+
prev = i915_active_set_exclusive(&vma->active, &work->base.dma);
if (prev) {
__i915_sw_fence_await_dma_fence(&work->base.chain,
@@ -424,8 +432,6 @@ int i915_vma_bind(struct i915_vma *vma,
dma_fence_put(prev);
}

- work->base.dma.error = 0; /* enable the queue_work() */
-
if (vma->obj) {
__i915_gem_object_pin_pages(vma->obj);
work->pinned = i915_gem_object_get(vma->obj);
--
2.31.1