linux/drivers/gpu/drm/i915/selftests/igt_spinner.c
Chris Wilson 16f2941ad3 drm/i915/gt: Replace direct submit with direct call to tasklet
Rather than having special case code for opportunistically calling
process_csb() and performing a direct submit while holding the engine
spinlock for submitting the request, simply call the tasklet directly.
This allows us to retain the direct submission path, including the CS
draining to allow fast/immediate submissions, without requiring any
duplicated code paths, and most importantly greatly simplifying the
control flow by removing reentrancy. This will enable us to close a few
races in the virtual engines in the next few patches.

The trickiest part here is to ensure that paired operations (such as
schedule_in/schedule_out) remain under consistent locking domains,
e.g. when pulled outside of the engine->active.lock

v2: Use bh kicking, see commit 3c53776e29 ("Mark HI and TASKLET
softirq synchronous").
v3: Update engine-reset to be tasklet aware

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201224135544.1713-1-chris@chris-wilson.co.uk
2020-12-24 15:02:35 +00:00

233 lines
5.2 KiB
C

/*
* SPDX-License-Identifier: MIT
*
* Copyright © 2018 Intel Corporation
*/
#include "gt/intel_gpu_commands.h"
#include "gt/intel_gt.h"
#include "gem/selftests/igt_gem_utils.h"
#include "igt_spinner.h"
int igt_spinner_init(struct igt_spinner *spin, struct intel_gt *gt)
{
unsigned int mode;
void *vaddr;
int err;
memset(spin, 0, sizeof(*spin));
spin->gt = gt;
spin->hws = i915_gem_object_create_internal(gt->i915, PAGE_SIZE);
if (IS_ERR(spin->hws)) {
err = PTR_ERR(spin->hws);
goto err;
}
spin->obj = i915_gem_object_create_internal(gt->i915, PAGE_SIZE);
if (IS_ERR(spin->obj)) {
err = PTR_ERR(spin->obj);
goto err_hws;
}
i915_gem_object_set_cache_coherency(spin->hws, I915_CACHE_LLC);
vaddr = i915_gem_object_pin_map(spin->hws, I915_MAP_WB);
if (IS_ERR(vaddr)) {
err = PTR_ERR(vaddr);
goto err_obj;
}
spin->seqno = memset(vaddr, 0xff, PAGE_SIZE);
mode = i915_coherent_map_type(gt->i915);
vaddr = i915_gem_object_pin_map(spin->obj, mode);
if (IS_ERR(vaddr)) {
err = PTR_ERR(vaddr);
goto err_unpin_hws;
}
spin->batch = vaddr;
return 0;
err_unpin_hws:
i915_gem_object_unpin_map(spin->hws);
err_obj:
i915_gem_object_put(spin->obj);
err_hws:
i915_gem_object_put(spin->hws);
err:
return err;
}
static unsigned int seqno_offset(u64 fence)
{
return offset_in_page(sizeof(u32) * fence);
}
static u64 hws_address(const struct i915_vma *hws,
const struct i915_request *rq)
{
return hws->node.start + seqno_offset(rq->fence.context);
}
static int move_to_active(struct i915_vma *vma,
struct i915_request *rq,
unsigned int flags)
{
int err;
i915_vma_lock(vma);
err = i915_request_await_object(rq, vma->obj,
flags & EXEC_OBJECT_WRITE);
if (err == 0)
err = i915_vma_move_to_active(vma, rq, flags);
i915_vma_unlock(vma);
return err;
}
struct i915_request *
igt_spinner_create_request(struct igt_spinner *spin,
struct intel_context *ce,
u32 arbitration_command)
{
struct intel_engine_cs *engine = ce->engine;
struct i915_request *rq = NULL;
struct i915_vma *hws, *vma;
unsigned int flags;
u32 *batch;
int err;
GEM_BUG_ON(spin->gt != ce->vm->gt);
if (!intel_engine_can_store_dword(ce->engine))
return ERR_PTR(-ENODEV);
vma = i915_vma_instance(spin->obj, ce->vm, NULL);
if (IS_ERR(vma))
return ERR_CAST(vma);
hws = i915_vma_instance(spin->hws, ce->vm, NULL);
if (IS_ERR(hws))
return ERR_CAST(hws);
err = i915_vma_pin(vma, 0, 0, PIN_USER);
if (err)
return ERR_PTR(err);
err = i915_vma_pin(hws, 0, 0, PIN_USER);
if (err)
goto unpin_vma;
rq = intel_context_create_request(ce);
if (IS_ERR(rq)) {
err = PTR_ERR(rq);
goto unpin_hws;
}
err = move_to_active(vma, rq, 0);
if (err)
goto cancel_rq;
err = move_to_active(hws, rq, 0);
if (err)
goto cancel_rq;
batch = spin->batch;
if (INTEL_GEN(rq->engine->i915) >= 8) {
*batch++ = MI_STORE_DWORD_IMM_GEN4;
*batch++ = lower_32_bits(hws_address(hws, rq));
*batch++ = upper_32_bits(hws_address(hws, rq));
} else if (INTEL_GEN(rq->engine->i915) >= 6) {
*batch++ = MI_STORE_DWORD_IMM_GEN4;
*batch++ = 0;
*batch++ = hws_address(hws, rq);
} else if (INTEL_GEN(rq->engine->i915) >= 4) {
*batch++ = MI_STORE_DWORD_IMM_GEN4 | MI_USE_GGTT;
*batch++ = 0;
*batch++ = hws_address(hws, rq);
} else {
*batch++ = MI_STORE_DWORD_IMM | MI_MEM_VIRTUAL;
*batch++ = hws_address(hws, rq);
}
*batch++ = rq->fence.seqno;
*batch++ = arbitration_command;
if (INTEL_GEN(rq->engine->i915) >= 8)
*batch++ = MI_BATCH_BUFFER_START | BIT(8) | 1;
else if (IS_HASWELL(rq->engine->i915))
*batch++ = MI_BATCH_BUFFER_START | MI_BATCH_PPGTT_HSW;
else if (INTEL_GEN(rq->engine->i915) >= 6)
*batch++ = MI_BATCH_BUFFER_START;
else
*batch++ = MI_BATCH_BUFFER_START | MI_BATCH_GTT;
*batch++ = lower_32_bits(vma->node.start);
*batch++ = upper_32_bits(vma->node.start);
*batch++ = MI_BATCH_BUFFER_END; /* not reached */
intel_gt_chipset_flush(engine->gt);
if (engine->emit_init_breadcrumb) {
err = engine->emit_init_breadcrumb(rq);
if (err)
goto cancel_rq;
}
flags = 0;
if (INTEL_GEN(rq->engine->i915) <= 5)
flags |= I915_DISPATCH_SECURE;
err = engine->emit_bb_start(rq, vma->node.start, PAGE_SIZE, flags);
cancel_rq:
if (err) {
i915_request_set_error_once(rq, err);
i915_request_add(rq);
}
unpin_hws:
i915_vma_unpin(hws);
unpin_vma:
i915_vma_unpin(vma);
return err ? ERR_PTR(err) : rq;
}
static u32
hws_seqno(const struct igt_spinner *spin, const struct i915_request *rq)
{
u32 *seqno = spin->seqno + seqno_offset(rq->fence.context);
return READ_ONCE(*seqno);
}
void igt_spinner_end(struct igt_spinner *spin)
{
*spin->batch = MI_BATCH_BUFFER_END;
intel_gt_chipset_flush(spin->gt);
}
void igt_spinner_fini(struct igt_spinner *spin)
{
igt_spinner_end(spin);
i915_gem_object_unpin_map(spin->obj);
i915_gem_object_put(spin->obj);
i915_gem_object_unpin_map(spin->hws);
i915_gem_object_put(spin->hws);
}
bool igt_wait_for_spinner(struct igt_spinner *spin, struct i915_request *rq)
{
if (i915_request_is_ready(rq))
intel_engine_flush_submission(rq->engine);
return !(wait_for_us(i915_seqno_passed(hws_seqno(spin, rq),
rq->fence.seqno),
100) &&
wait_for(i915_seqno_passed(hws_seqno(spin, rq),
rq->fence.seqno),
50));
}