drm/vmwgfx: Stabilize the command buffer submission code

This commit addresses some stability problems with the command buffer
submission code recently introduced:

1) Make the vmw_cmdbuf_man_process() function handle reruns internally to
avoid losing interrupts if the caller forgets to rerun on -EAGAIN.
2) Handle default command buffer allocations using inline command buffers.
This avoids rare allocation deadlocks.
3) In case of command buffer errors we might lose fence submissions.
Therefore send a new fence after each command buffer error. This will help
avoid lengthy fence waits.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Sinclair Yeh <syeh@vmware.com>
This commit is contained in:
Thomas Hellstrom 2015-10-21 21:31:49 +02:00
parent ed7d78b2da
commit 09dc1387c9
1 changed files with 20 additions and 14 deletions

View File

@ -415,16 +415,16 @@ static void vmw_cmdbuf_ctx_process(struct vmw_cmdbuf_man *man,
*
* Calls vmw_cmdbuf_ctx_process() on all contexts. If any context has
* command buffers left that are not submitted to hardware, Make sure
* IRQ handling is turned on. Otherwise, make sure it's turned off. This
* function may return -EAGAIN to indicate it should be rerun due to
* possibly missed IRQs if IRQs has just been turned on.
* IRQ handling is turned on. Otherwise, make sure it's turned off.
*/
static int vmw_cmdbuf_man_process(struct vmw_cmdbuf_man *man)
static void vmw_cmdbuf_man_process(struct vmw_cmdbuf_man *man)
{
int notempty = 0;
int notempty;
struct vmw_cmdbuf_context *ctx;
int i;
retry:
notempty = 0;
for_each_cmdbuf_ctx(man, i, ctx)
vmw_cmdbuf_ctx_process(man, ctx, &notempty);
@ -440,10 +440,8 @@ static int vmw_cmdbuf_man_process(struct vmw_cmdbuf_man *man)
man->irq_on = true;
/* Rerun in case we just missed an irq. */
return -EAGAIN;
goto retry;
}
return 0;
}
/**
@ -468,8 +466,7 @@ static void vmw_cmdbuf_ctx_add(struct vmw_cmdbuf_man *man,
header->cb_context = cb_context;
list_add_tail(&header->list, &man->ctx[cb_context].submitted);
if (vmw_cmdbuf_man_process(man) == -EAGAIN)
vmw_cmdbuf_man_process(man);
vmw_cmdbuf_man_process(man);
}
/**
@ -488,8 +485,7 @@ static void vmw_cmdbuf_man_tasklet(unsigned long data)
struct vmw_cmdbuf_man *man = (struct vmw_cmdbuf_man *) data;
spin_lock(&man->lock);
if (vmw_cmdbuf_man_process(man) == -EAGAIN)
(void) vmw_cmdbuf_man_process(man);
vmw_cmdbuf_man_process(man);
spin_unlock(&man->lock);
}
@ -507,6 +503,7 @@ static void vmw_cmdbuf_work_func(struct work_struct *work)
struct vmw_cmdbuf_man *man =
container_of(work, struct vmw_cmdbuf_man, work);
struct vmw_cmdbuf_header *entry, *next;
uint32_t dummy;
bool restart = false;
spin_lock_bh(&man->lock);
@ -523,6 +520,8 @@ static void vmw_cmdbuf_work_func(struct work_struct *work)
if (restart && vmw_cmdbuf_startstop(man, true))
DRM_ERROR("Failed restarting command buffer context 0.\n");
/* Send a new fence in case one was removed */
vmw_fifo_send_fence(man->dev_priv, &dummy);
}
/**
@ -682,7 +681,7 @@ static bool vmw_cmdbuf_try_alloc(struct vmw_cmdbuf_man *man,
DRM_MM_SEARCH_DEFAULT,
DRM_MM_CREATE_DEFAULT);
if (ret) {
(void) vmw_cmdbuf_man_process(man);
vmw_cmdbuf_man_process(man);
ret = drm_mm_insert_node_generic(&man->mm, info->node,
info->page_size, 0, 0,
DRM_MM_SEARCH_DEFAULT,
@ -1168,7 +1167,14 @@ int vmw_cmdbuf_set_pool_size(struct vmw_cmdbuf_man *man,
drm_mm_init(&man->mm, 0, size >> PAGE_SHIFT);
man->has_pool = true;
man->default_size = default_size;
/*
* For now, set the default size to VMW_CMDBUF_INLINE_SIZE to
* prevent deadlocks from happening when vmw_cmdbuf_space_pool()
* needs to wait for space and we block on further command
* submissions to be able to free up space.
*/
man->default_size = VMW_CMDBUF_INLINE_SIZE;
DRM_INFO("Using command buffers with %s pool.\n",
(man->using_mob) ? "MOB" : "DMA");