Skip to content

Commit

Permalink
drm/xe: Drop xe_gt_tlb_invalidation_wait
Browse files Browse the repository at this point in the history 
Having two methods to wait on GT TLB invalidations is not ideal. Remove
xe_gt_tlb_invalidation_wait and only use GT TLB invalidation fences.

In addition to two methods being less than ideal, once GT TLB
invalidations are coalesced the seqno cannot be assigned during
xe_gt_tlb_invalidation_ggtt/range. Thus xe_gt_tlb_invalidation_wait
would not have a seqno to wait one. A fence however can be armed and
later signaled.

v3:
 - Add explaination about coalescing to commit message
v4:
 - Don't put dma fence if defined on stack (CI)
v5:
 - Initialize ret to zero (CI)
v6:
 - Use invalidation_fence_signal helper in tlb timeout (Matthew Auld)

Signed-off-by: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Nirmoy Das <nirmoy.das@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240719172905.1527927-3-matthew.brost@intel.com
  • Loading branch information
Matthew Brost committed Jul 20, 2024
1 parent a522b28 commit 61ac035
Show file tree
Hide file tree
Showing 4 changed files with 80 additions and 110 deletions.
148 changes: 55 additions & 93 deletions drivers/gpu/drm/xe/xe_gt_tlb_invalidation.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -17,6 +17,8 @@
#include "xe_trace.h"
#include "regs/xe_guc_regs.h"

#define FENCE_STACK_BIT DMA_FENCE_FLAG_USER_BITS

/*
* TLB inval depends on pending commands in the CT queue and then the real
* invalidation time. Double up the time to process full CT queue
Expand All @@ -33,6 +35,23 @@ static long tlb_timeout_jiffies(struct xe_gt *gt)
return hw_tlb_timeout + 2 * delay;
}

static void
__invalidation_fence_signal(struct xe_device *xe, struct xe_gt_tlb_invalidation_fence *fence)
{
bool stack = test_bit(FENCE_STACK_BIT, &fence->base.flags);

trace_xe_gt_tlb_invalidation_fence_signal(xe, fence);
dma_fence_signal(&fence->base);
if (!stack)
dma_fence_put(&fence->base);
}

static void
invalidation_fence_signal(struct xe_device *xe, struct xe_gt_tlb_invalidation_fence *fence)
{
list_del(&fence->link);
__invalidation_fence_signal(xe, fence);
}

static void xe_gt_tlb_fence_timeout(struct work_struct *work)
{
Expand All @@ -54,10 +73,8 @@ static void xe_gt_tlb_fence_timeout(struct work_struct *work)
xe_gt_err(gt, "TLB invalidation fence timeout, seqno=%d recv=%d",
fence->seqno, gt->tlb_invalidation.seqno_recv);

list_del(&fence->link);
fence->base.error = -ETIME;
dma_fence_signal(&fence->base);
dma_fence_put(&fence->base);
invalidation_fence_signal(xe, fence);
}
if (!list_empty(&gt->tlb_invalidation.pending_fences))
queue_delayed_work(system_wq,
Expand Down Expand Up @@ -87,21 +104,6 @@ int xe_gt_tlb_invalidation_init(struct xe_gt *gt)
return 0;
}

static void
__invalidation_fence_signal(struct xe_device *xe, struct xe_gt_tlb_invalidation_fence *fence)
{
trace_xe_gt_tlb_invalidation_fence_signal(xe, fence);
dma_fence_signal(&fence->base);
dma_fence_put(&fence->base);
}

static void
invalidation_fence_signal(struct xe_device *xe, struct xe_gt_tlb_invalidation_fence *fence)
{
list_del(&fence->link);
__invalidation_fence_signal(xe, fence);
}

/**
* xe_gt_tlb_invalidation_reset - Initialize GT TLB invalidation reset
* @gt: graphics tile
Expand All @@ -111,7 +113,6 @@ invalidation_fence_signal(struct xe_device *xe, struct xe_gt_tlb_invalidation_fe
void xe_gt_tlb_invalidation_reset(struct xe_gt *gt)
{
struct xe_gt_tlb_invalidation_fence *fence, *next;
struct xe_guc *guc = &gt->uc.guc;
int pending_seqno;

/*
Expand All @@ -134,7 +135,6 @@ void xe_gt_tlb_invalidation_reset(struct xe_gt *gt)
else
pending_seqno = gt->tlb_invalidation.seqno - 1;
WRITE_ONCE(gt->tlb_invalidation.seqno_recv, pending_seqno);
wake_up_all(&guc->ct.wq);

list_for_each_entry_safe(fence, next,
&gt->tlb_invalidation.pending_fences, link)
Expand Down Expand Up @@ -165,6 +165,8 @@ static int send_tlb_invalidation(struct xe_guc *guc,
int seqno;
int ret;

xe_gt_assert(gt, fence);

/*
* XXX: The seqno algorithm relies on TLB invalidation being processed
* in order which they currently are, if that changes the algorithm will
Expand All @@ -173,10 +175,8 @@ static int send_tlb_invalidation(struct xe_guc *guc,

mutex_lock(&guc->ct.lock);
seqno = gt->tlb_invalidation.seqno;
if (fence) {
fence->seqno = seqno;
trace_xe_gt_tlb_invalidation_fence_send(xe, fence);
}
fence->seqno = seqno;
trace_xe_gt_tlb_invalidation_fence_send(xe, fence);
action[1] = seqno;
ret = xe_guc_ct_send_locked(&guc->ct, action, len,
G2H_LEN_DW_TLB_INVALIDATE, 1);
Expand Down Expand Up @@ -209,7 +209,6 @@ static int send_tlb_invalidation(struct xe_guc *guc,
TLB_INVALIDATION_SEQNO_MAX;
if (!gt->tlb_invalidation.seqno)
gt->tlb_invalidation.seqno = 1;
ret = seqno;
}
mutex_unlock(&guc->ct.lock);

Expand All @@ -223,22 +222,24 @@ static int send_tlb_invalidation(struct xe_guc *guc,
/**
* xe_gt_tlb_invalidation_guc - Issue a TLB invalidation on this GT for the GuC
* @gt: graphics tile
* @fence: invalidation fence which will be signal on TLB invalidation
* completion
*
* Issue a TLB invalidation for the GuC. Completion of TLB is asynchronous and
* caller can use seqno + xe_gt_tlb_invalidation_wait to wait for completion.
* caller can use the invalidation fence to wait for completion.
*
* Return: Seqno which can be passed to xe_gt_tlb_invalidation_wait on success,
* negative error code on error.
* Return: 0 on success, negative error code on error
*/
static int xe_gt_tlb_invalidation_guc(struct xe_gt *gt)
static int xe_gt_tlb_invalidation_guc(struct xe_gt *gt,
struct xe_gt_tlb_invalidation_fence *fence)
{
u32 action[] = {
XE_GUC_ACTION_TLB_INVALIDATION,
0, /* seqno, replaced in send_tlb_invalidation */
MAKE_INVAL_OP(XE_GUC_TLB_INVAL_GUC),
};

return send_tlb_invalidation(&gt->uc.guc, NULL, action,
return send_tlb_invalidation(&gt->uc.guc, fence, action,
ARRAY_SIZE(action));
}

Expand All @@ -257,13 +258,15 @@ int xe_gt_tlb_invalidation_ggtt(struct xe_gt *gt)

if (xe_guc_ct_enabled(&gt->uc.guc.ct) &&
gt->uc.guc.submission_state.enabled) {
int seqno;
struct xe_gt_tlb_invalidation_fence fence;
int ret;

seqno = xe_gt_tlb_invalidation_guc(gt);
if (seqno <= 0)
return seqno;
xe_gt_tlb_invalidation_fence_init(gt, &fence, true);
ret = xe_gt_tlb_invalidation_guc(gt, &fence);
if (ret < 0)
return ret;

xe_gt_tlb_invalidation_wait(gt, seqno);
xe_gt_tlb_invalidation_fence_wait(&fence);
} else if (xe_device_uc_enabled(xe) && !xe_device_wedged(xe)) {
if (IS_SRIOV_VF(xe))
return 0;
Expand All @@ -290,18 +293,16 @@ int xe_gt_tlb_invalidation_ggtt(struct xe_gt *gt)
*
* @gt: graphics tile
* @fence: invalidation fence which will be signal on TLB invalidation
* completion, can be NULL
* completion
* @start: start address
* @end: end address
* @asid: address space id
*
* Issue a range based TLB invalidation if supported, if not fallback to a full
* TLB invalidation. Completion of TLB is asynchronous and caller can either use
* the invalidation fence or seqno + xe_gt_tlb_invalidation_wait to wait for
* completion.
* TLB invalidation. Completion of TLB is asynchronous and caller can use
* the invalidation fence to wait for completion.
*
* Return: Seqno which can be passed to xe_gt_tlb_invalidation_wait on success,
* negative error code on error.
* Return: Negative error code on error, 0 on success
*/
int xe_gt_tlb_invalidation_range(struct xe_gt *gt,
struct xe_gt_tlb_invalidation_fence *fence,
Expand All @@ -312,11 +313,11 @@ int xe_gt_tlb_invalidation_range(struct xe_gt *gt,
u32 action[MAX_TLB_INVALIDATION_LEN];
int len = 0;

xe_gt_assert(gt, fence);

/* Execlists not supported */
if (gt_to_xe(gt)->info.force_execlist) {
if (fence)
__invalidation_fence_signal(xe, fence);

__invalidation_fence_signal(xe, fence);
return 0;
}

Expand Down Expand Up @@ -382,12 +383,10 @@ int xe_gt_tlb_invalidation_range(struct xe_gt *gt,
* @vma: VMA to invalidate
*
* Issue a range based TLB invalidation if supported, if not fallback to a full
* TLB invalidation. Completion of TLB is asynchronous and caller can either use
* the invalidation fence or seqno + xe_gt_tlb_invalidation_wait to wait for
* completion.
* TLB invalidation. Completion of TLB is asynchronous and caller can use
* the invalidation fence to wait for completion.
*
* Return: Seqno which can be passed to xe_gt_tlb_invalidation_wait on success,
* negative error code on error.
* Return: Negative error code on error, 0 on success
*/
int xe_gt_tlb_invalidation_vma(struct xe_gt *gt,
struct xe_gt_tlb_invalidation_fence *fence,
Expand All @@ -400,43 +399,6 @@ int xe_gt_tlb_invalidation_vma(struct xe_gt *gt,
xe_vma_vm(vma)->usm.asid);
}

/**
* xe_gt_tlb_invalidation_wait - Wait for TLB to complete
* @gt: graphics tile
* @seqno: seqno to wait which was returned from xe_gt_tlb_invalidation
*
* Wait for tlb_timeout_jiffies() for a TLB invalidation to complete.
*
* Return: 0 on success, -ETIME on TLB invalidation timeout
*/
int xe_gt_tlb_invalidation_wait(struct xe_gt *gt, int seqno)
{
struct xe_guc *guc = &gt->uc.guc;
int ret;

/* Execlists not supported */
if (gt_to_xe(gt)->info.force_execlist)
return 0;

/*
* XXX: See above, this algorithm only works if seqno are always in
* order
*/
ret = wait_event_timeout(guc->ct.wq,
tlb_invalidation_seqno_past(gt, seqno),
tlb_timeout_jiffies(gt));
if (!ret) {
struct drm_printer p = xe_gt_err_printer(gt);

xe_gt_err(gt, "TLB invalidation time'd out, seqno=%d, recv=%d\n",
seqno, gt->tlb_invalidation.seqno_recv);
xe_guc_ct_print(&guc->ct, &p, true);
return -ETIME;
}

return 0;
}

/**
* xe_guc_tlb_invalidation_done_handler - TLB invalidation done handler
* @guc: guc
Expand Down Expand Up @@ -480,12 +442,7 @@ int xe_guc_tlb_invalidation_done_handler(struct xe_guc *guc, u32 *msg, u32 len)
return 0;
}

/*
* wake_up_all() and wait_event_timeout() already have the correct
* barriers.
*/
WRITE_ONCE(gt->tlb_invalidation.seqno_recv, msg[0]);
wake_up_all(&guc->ct.wq);

list_for_each_entry_safe(fence, next,
&gt->tlb_invalidation.pending_fences, link) {
Expand Down Expand Up @@ -530,17 +487,22 @@ static const struct dma_fence_ops invalidation_fence_ops = {
* xe_gt_tlb_invalidation_fence_init - Initialize TLB invalidation fence
* @gt: GT
* @fence: TLB invalidation fence to initialize
* @stack: fence is stack variable
*
* Initialize TLB invalidation fence for use
*/
void xe_gt_tlb_invalidation_fence_init(struct xe_gt *gt,
struct xe_gt_tlb_invalidation_fence *fence)
struct xe_gt_tlb_invalidation_fence *fence,
bool stack)
{
spin_lock_irq(&gt->tlb_invalidation.lock);
dma_fence_init(&fence->base, &invalidation_fence_ops,
&gt->tlb_invalidation.lock,
dma_fence_context_alloc(1), 1);
spin_unlock_irq(&gt->tlb_invalidation.lock);
INIT_LIST_HEAD(&fence->link);
dma_fence_get(&fence->base);
if (stack)
set_bit(FENCE_STACK_BIT, &fence->base.flags);
else
dma_fence_get(&fence->base);
}
10 changes: 8 additions & 2 deletions drivers/gpu/drm/xe/xe_gt_tlb_invalidation.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -23,10 +23,16 @@ int xe_gt_tlb_invalidation_vma(struct xe_gt *gt,
int xe_gt_tlb_invalidation_range(struct xe_gt *gt,
struct xe_gt_tlb_invalidation_fence *fence,
u64 start, u64 end, u32 asid);
int xe_gt_tlb_invalidation_wait(struct xe_gt *gt, int seqno);
int xe_guc_tlb_invalidation_done_handler(struct xe_guc *guc, u32 *msg, u32 len);

void xe_gt_tlb_invalidation_fence_init(struct xe_gt *gt,
struct xe_gt_tlb_invalidation_fence *fence);
struct xe_gt_tlb_invalidation_fence *fence,
bool stack);

static inline void
xe_gt_tlb_invalidation_fence_wait(struct xe_gt_tlb_invalidation_fence *fence)
{
dma_fence_wait(&fence->base, false);
}

#endif /* _XE_GT_TLB_INVALIDATION_ */
2 changes: 1 addition & 1 deletion drivers/gpu/drm/xe/xe_pt.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -1355,7 +1355,7 @@ static void invalidation_fence_init(struct xe_gt *gt,

trace_xe_gt_tlb_invalidation_fence_create(gt_to_xe(gt), &ifence->base);

xe_gt_tlb_invalidation_fence_init(gt, &ifence->base);
xe_gt_tlb_invalidation_fence_init(gt, &ifence->base, false);

ifence->fence = fence;
ifence->gt = gt;
Expand Down
30 changes: 16 additions & 14 deletions drivers/gpu/drm/xe/xe_vm.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -3180,10 +3180,10 @@ int xe_vm_invalidate_vma(struct xe_vma *vma)
{
struct xe_device *xe = xe_vma_vm(vma)->xe;
struct xe_tile *tile;
struct xe_gt_tlb_invalidation_fence fence[XE_MAX_TILES_PER_DEVICE];
u32 tile_needs_invalidate = 0;
int seqno[XE_MAX_TILES_PER_DEVICE];
u8 id;
int ret;
int ret = 0;

xe_assert(xe, !xe_vma_is_null(vma));
trace_xe_vma_invalidate(vma);
Expand All @@ -3208,29 +3208,31 @@ int xe_vm_invalidate_vma(struct xe_vma *vma)

for_each_tile(tile, xe, id) {
if (xe_pt_zap_ptes(tile, vma)) {
tile_needs_invalidate |= BIT(id);
xe_device_wmb(xe);
xe_gt_tlb_invalidation_fence_init(tile->primary_gt,
&fence[id], true);

/*
* FIXME: We potentially need to invalidate multiple
* GTs within the tile
*/
seqno[id] = xe_gt_tlb_invalidation_vma(tile->primary_gt, NULL, vma);
if (seqno[id] < 0)
return seqno[id];
}
}

for_each_tile(tile, xe, id) {
if (tile_needs_invalidate & BIT(id)) {
ret = xe_gt_tlb_invalidation_wait(tile->primary_gt, seqno[id]);
ret = xe_gt_tlb_invalidation_vma(tile->primary_gt,
&fence[id], vma);
if (ret < 0)
return ret;
goto wait;

tile_needs_invalidate |= BIT(id);
}
}

wait:
for_each_tile(tile, xe, id)
if (tile_needs_invalidate & BIT(id))
xe_gt_tlb_invalidation_fence_wait(&fence[id]);

vma->tile_invalidated = vma->tile_mask;

return 0;
return ret;
}

struct xe_vm_snapshot {
Expand Down

0 comments on commit 61ac035

Please sign in to comment.