Commit 42d10511 authored by Chris Wilson's avatar Chris Wilson
Browse files

drm/i915: Lift i915_vma_pin() out of intel_renderstate_emit() 



Once inside a request, inside the timeline->mutex, pinning is verboten.

<4> [896.032829] ======================================================
<4> [896.032831] WARNING: possible circular locking dependency detected
<4> [896.032835] 5.4.0-rc8-CI-Patchwork_15533+ #1 Tainted: G     U
<4> [896.032838] ------------------------------------------------------
<4> [896.032841] gem_exec_parall/3720 is trying to acquire lock:
<4> [896.032844] ffff888401863270 (&kernel#2){+.+.}, at: i915_request_create+0x16/0x1c0 [i915]
<4> [896.032915]
but task is already holding lock:
<4> [896.032917] ffff8883ec1c93c0 (&vm->mutex){+.+.}, at: i915_vma_pin+0xf3/0x11c0 [i915]
<4> [896.032952]
which lock already depends on the new lock.

<4> [896.032954]
the existing dependency chain (in reverse order) is:
<4> [896.032956]
-> #1 (&vm->mutex){+.+.}:
<4> [896.032961]        __mutex_lock+0x9a/0x9d0
<4> [896.032995]        i915_vma_pin+0xf3/0x11c0 [i915]
<4> [896.033033]        intel_renderstate_emit+0xb9/0x9e0 [i915]
<4> [896.033081]        i915_gem_init+0x5a9/0xa50 [i915]
<4> [896.033112]        i915_driver_probe+0xb00/0x15f0 [i915]
<4> [896.033144]        i915_pci_probe+0x43/0x1c0 [i915]
<4> [896.033149]        pci_device_probe+0x9e/0x120
<4> [896.033154]        really_probe+0xea/0x420
<4> [896.033158]        driver_probe_device+0x10b/0x120
<4> [896.033161]        device_driver_attach+0x4a/0x50
<4> [896.033164]        __driver_attach+0x97/0x130
<4> [896.033168]        bus_for_each_dev+0x74/0xc0
<4> [896.033171]        bus_add_driver+0x142/0x220
<4> [896.033174]        driver_register+0x56/0xf0
<4> [896.033178]        do_one_initcall+0x58/0x2ff
<4> [896.033183]        do_init_module+0x56/0x1f8
<4> [896.033187]        load_module+0x243e/0x29f0
<4> [896.033190]        __do_sys_finit_module+0xe9/0x110
<4> [896.033194]        do_syscall_64+0x4f/0x210
<4> [896.033197]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
<4> [896.033200]
-> #0 (&kernel#2){+.+.}:
<4> [896.033206]        __lock_acquire+0x1328/0x15d0
<4> [896.033209]        lock_acquire+0xa7/0x1c0
<4> [896.033213]        __mutex_lock+0x9a/0x9d0
<4> [896.033255]        i915_request_create+0x16/0x1c0 [i915]
<4> [896.033287]        intel_engine_flush_barriers+0x4c/0x100 [i915]
<4> [896.033327]        ggtt_flush+0x37/0x60 [i915]
<4> [896.033366]        i915_gem_evict_something+0x46b/0x5a0 [i915]
<4> [896.033407]        i915_gem_gtt_insert+0x21d/0x6a0 [i915]
<4> [896.033449]        i915_vma_pin+0xb36/0x11c0 [i915]
<4> [896.033488]        gen6_ppgtt_pin+0xd5/0x170 [i915]
<4> [896.033523]        ring_context_pin+0x2e/0xc0 [i915]
<4> [896.033554]        __intel_context_do_pin+0x6b/0x190 [i915]
<4> [896.033591]        i915_gem_do_execbuffer+0x1814/0x26c0 [i915]
<4> [896.033627]        i915_gem_execbuffer2_ioctl+0x11b/0x460 [i915]
<4> [896.033632]        drm_ioctl_kernel+0xa7/0xf0
<4> [896.033635]        drm_ioctl+0x2e1/0x390
<4> [896.033638]        do_vfs_ioctl+0xa0/0x6f0
<4> [896.033641]        ksys_ioctl+0x35/0x60
<4> [896.033644]        __x64_sys_ioctl+0x11/0x20
<4> [896.033647]        do_syscall_64+0x4f/0x210
<4> [896.033650]        entry_SYSCALL_64_after_hwframe+0x49/0xbe

Lift the object allocation and pin prior to the request construction.

Signed-off-by: default avatarChris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Reviewed-by: default avatarMika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191202204316.2665847-1-chris@chris-wilson.co.uk
parent 3e817471

drivers/gpu/drm/i915/gt/intel_renderstate.c

+55 −42
Original line number Diff line number Diff line
@@ -29,16 +29,6 @@ 
#include "intel_renderstate.h"

#include "intel_ring.h"



struct intel_renderstate {

	const struct intel_renderstate_rodata *rodata;

	struct drm_i915_gem_object *obj;

	struct i915_vma *vma;

	u32 batch_offset;

	u32 batch_size;

	u32 aux_offset;

	u32 aux_size;

};



static const struct intel_renderstate_rodata *

render_state_get_rodata(const struct intel_engine_cs *engine)

{
@@ -84,11 +74,11 @@ static int render_state_setup(struct intel_renderstate *so, 
	u32 *d;

	int ret;



	ret = i915_gem_object_prepare_write(so->obj, &needs_clflush);

	ret = i915_gem_object_prepare_write(so->vma->obj, &needs_clflush);

	if (ret)

		return ret;



	d = kmap_atomic(i915_gem_object_get_dirty_page(so->obj, 0));

	d = kmap_atomic(i915_gem_object_get_dirty_page(so->vma->obj, 0));



	while (i < rodata->batch_items) {

		u32 s = rodata->batch[i];
@@ -166,7 +156,7 @@ static int render_state_setup(struct intel_renderstate *so, 


	ret = 0;

out:

	i915_gem_object_finish_access(so->obj);

	i915_gem_object_finish_access(so->vma->obj);

	return ret;



err:
@@ -177,61 +167,84 @@ static int render_state_setup(struct intel_renderstate *so, 


#undef OUT_BATCH



int intel_renderstate_emit(struct i915_request *rq)

int intel_renderstate_init(struct intel_renderstate *so,

			   struct intel_engine_cs *engine)

{

	struct intel_engine_cs *engine = rq->engine;

	struct intel_renderstate so = {}; /* keep the compiler happy */

	struct drm_i915_gem_object *obj;

	int err;



	so.rodata = render_state_get_rodata(engine);

	if (!so.rodata)

	memset(so, 0, sizeof(*so));



	so->rodata = render_state_get_rodata(engine);

	if (!so->rodata)

		return 0;



	if (so.rodata->batch_items * 4 > PAGE_SIZE)

	if (so->rodata->batch_items * 4 > PAGE_SIZE)

		return -EINVAL;



	so.obj = i915_gem_object_create_internal(engine->i915, PAGE_SIZE);

	if (IS_ERR(so.obj))

		return PTR_ERR(so.obj);

	obj = i915_gem_object_create_internal(engine->i915, PAGE_SIZE);

	if (IS_ERR(obj))

		return PTR_ERR(obj);



	so.vma = i915_vma_instance(so.obj, &engine->gt->ggtt->vm, NULL);

	if (IS_ERR(so.vma)) {

		err = PTR_ERR(so.vma);

	so->vma = i915_vma_instance(obj, &engine->gt->ggtt->vm, NULL);

	if (IS_ERR(so->vma)) {

		err = PTR_ERR(so->vma);

		goto err_obj;

	}



	err = i915_vma_pin(so.vma, 0, 0, PIN_GLOBAL | PIN_HIGH);

	err = i915_vma_pin(so->vma, 0, 0, PIN_GLOBAL | PIN_HIGH);

	if (err)

		goto err_vma;



	err = render_state_setup(&so, rq->i915);

	err = render_state_setup(so, engine->i915);

	if (err)

		goto err_unpin;



	return 0;



err_unpin:

	i915_vma_unpin(so->vma);

err_vma:

	i915_vma_close(so->vma);

err_obj:

	i915_gem_object_put(obj);

	so->vma = NULL;

	return err;

}



int intel_renderstate_emit(struct intel_renderstate *so,

			   struct i915_request *rq)

{

	struct intel_engine_cs *engine = rq->engine;

	int err;



	if (!so->vma)

		return 0;



	err = engine->emit_bb_start(rq,

				    so.batch_offset, so.batch_size,

				    so->batch_offset, so->batch_size,

				    I915_DISPATCH_SECURE);

	if (err)

		goto err_unpin;

		return err;



	if (so.aux_size > 8) {

	if (so->aux_size > 8) {

		err = engine->emit_bb_start(rq,

					    so.aux_offset, so.aux_size,

					    so->aux_offset, so->aux_size,

					    I915_DISPATCH_SECURE);

		if (err)

			goto err_unpin;

			return err;

	}



	i915_vma_lock(so.vma);

	err = i915_request_await_object(rq, so.vma->obj, false);

	i915_vma_lock(so->vma);

	err = i915_request_await_object(rq, so->vma->obj, false);

	if (err == 0)

		err = i915_vma_move_to_active(so.vma, rq, 0);

	i915_vma_unlock(so.vma);

err_unpin:

	i915_vma_unpin(so.vma);

err_vma:

	i915_vma_close(so.vma);

err_obj:

	i915_gem_object_put(so.obj);

		err = i915_vma_move_to_active(so->vma, rq, 0);

	i915_vma_unlock(so->vma);



	return err;

}



void intel_renderstate_fini(struct intel_renderstate *so)

{

	i915_vma_unpin_and_release(&so->vma, 0);

}

drivers/gpu/drm/i915/gt/intel_renderstate.h

+16 −1
Original line number Diff line number Diff line
@@ -27,6 +27,8 @@ 
#include <linux/types.h>



struct i915_request;

struct intel_engine_cs;

struct i915_vma;



struct intel_renderstate_rodata {

	const u32 *reloc;
@@ -46,6 +48,19 @@ extern const struct intel_renderstate_rodata gen7_null_state; 
extern const struct intel_renderstate_rodata gen8_null_state;

extern const struct intel_renderstate_rodata gen9_null_state;



int intel_renderstate_emit(struct i915_request *rq);

struct intel_renderstate {

	const struct intel_renderstate_rodata *rodata;

	struct i915_vma *vma;

	u32 batch_offset;

	u32 batch_size;

	u32 aux_offset;

	u32 aux_size;

};



int intel_renderstate_init(struct intel_renderstate *so,

			   struct intel_engine_cs *engine);

int intel_renderstate_emit(struct intel_renderstate *so,

			   struct i915_request *rq);

void intel_renderstate_fini(struct intel_renderstate *so);



#endif /* _INTEL_RENDERSTATE_H_ */

drivers/gpu/drm/i915/i915_gem.c

+7 −1
Original line number Diff line number Diff line
@@ -1086,9 +1086,14 @@ static int __intel_engines_record_defaults(struct intel_gt *gt) 
	 */



	for_each_engine(engine, gt, id) {

		struct intel_renderstate so;

		struct intel_context *ce;

		struct i915_request *rq;



		err = intel_renderstate_init(&so, engine);

		if (err)

			goto out;



		/* We must be able to switch to something! */

		GEM_BUG_ON(!engine->kernel_context);

		engine->serial++; /* force the kernel context switch */
@@ -1111,13 +1116,14 @@ static int __intel_engines_record_defaults(struct intel_gt *gt) 
		if (err)

			goto err_rq;



		err = intel_renderstate_emit(rq);

		err = intel_renderstate_emit(&so, rq);

		if (err)

			goto err_rq;



err_rq:

		requests[id] = i915_request_get(rq);

		i915_request_add(rq);

		intel_renderstate_fini(&so);

		if (err)

			goto out;

	}