[PATCH 6/6] drm/xe: Introduce the busted_mode debugfs

[Lucas De Marchi]

On Fri, Mar 15, 2024 at 10:01:08AM -0400, Rodrigo Vivi wrote:
>So, the busted mode can be selected at runtime with the device
>granularity, rather then a module policy.

did you mean to squash this in the previous commit?

for the entire series, it seems it's going the right direction. It would
be good to have some more testing with it before merging though. I asked
SV folks to give it a try. I also saw some typos I forgot to comment on
so I will have to go through the patches again.

Another question is about naming since some people didn't like "busted".
Options:

1) keep busted
2) zombie
3) back to wedged
4) dead
5) blocked
6) disabled
7) unusable
8) unreliable
9) misbehaving

Did I miss any suggestion?  Well.... the order above is just _my_
preference, but I'm totally fine if other people disagree and we decide
something else.

Cc'ing some people who may chime in with their preference.

Lucas De Marchi

>
>Cc: Lucas De Marchi <lucas.demarchi at intel.com>
>Cc: Alan Previn <alan.previn.teres.alexis at intel.com>
>Signed-off-by: Rodrigo Vivi <rodrigo.vivi at intel.com>
>---
> drivers/gpu/drm/xe/xe_debugfs.c | 12 +++++++++
> drivers/gpu/drm/xe/xe_guc_ads.c | 46 +++++++++++++++++++++++++++++++++
> drivers/gpu/drm/xe/xe_guc_ads.h |  1 +
> 3 files changed, 59 insertions(+)
>
>diff --git a/drivers/gpu/drm/xe/xe_debugfs.c b/drivers/gpu/drm/xe/xe_debugfs.c
>index 175ba306c3eb..0cd20862d32e 100644
>--- a/drivers/gpu/drm/xe/xe_debugfs.c
>+++ b/drivers/gpu/drm/xe/xe_debugfs.c
>@@ -12,6 +12,7 @@
> #include "xe_bo.h"
> #include "xe_device.h"
> #include "xe_gt_debugfs.h"
>+#include "xe_guc_ads.h"
> #include "xe_pm.h"
> #include "xe_step.h"
>
>@@ -124,8 +125,10 @@ static ssize_t busted_mode_set(struct file *f, const char __user *ubuf,
> 			       size_t size, loff_t *pos)
> {
> 	struct xe_device *xe = file_inode(f)->i_private;
>+	struct xe_gt *gt;
> 	u32 busted_mode;
> 	ssize_t ret;
>+	u8 id;
>
> 	ret = kstrtouint_from_user(ubuf, size, 0, &busted_mode);
> 	if (ret)
>@@ -136,6 +139,15 @@ static ssize_t busted_mode_set(struct file *f, const char __user *ubuf,
>
> 	mutex_lock(&xe->busted.lock);
> 	xe->busted.mode = busted_mode;
>+	if (busted_mode == 2) {
>+		for_each_gt(gt, xe, id) {
>+			ret = xe_guc_ads_scheduler_policy_disable_reset(&gt->uc.guc.ads);
>+			if (ret) {
>+				drm_err(&xe->drm, "Failed to update GuC ADS scheduler policy. GPU might still reset even on the busted_mode=2\n");
>+				break;
>+			}
>+		}
>+	}
> 	mutex_unlock(&xe->busted.lock);
>
> 	return size;
>diff --git a/drivers/gpu/drm/xe/xe_guc_ads.c b/drivers/gpu/drm/xe/xe_guc_ads.c
>index 43f0a88bbe8a..5dccdbe595bf 100644
>--- a/drivers/gpu/drm/xe/xe_guc_ads.c
>+++ b/drivers/gpu/drm/xe/xe_guc_ads.c
>@@ -7,6 +7,7 @@
>
> #include <drm/drm_managed.h>
>
>+#include "abi/guc_actions_abi.h"
> #include "regs/xe_engine_regs.h"
> #include "regs/xe_gt_regs.h"
> #include "regs/xe_guc_regs.h"
>@@ -14,6 +15,7 @@
> #include "xe_gt.h"
> #include "xe_gt_ccs_mode.h"
> #include "xe_guc.h"
>+#include "xe_guc_ct.h"
> #include "xe_hw_engine.h"
> #include "xe_lrc.h"
> #include "xe_map.h"
>@@ -679,3 +681,47 @@ void xe_guc_ads_populate_post_load(struct xe_guc_ads *ads)
> {
> 	guc_populate_golden_lrc(ads);
> }
>+
>+static int guc_ads_action_update_policies(struct xe_guc_ads *ads, u32 policy_offset)
>+{
>+	struct  xe_guc_ct *ct = &ads_to_guc(ads)->ct;
>+	u32 action[] = {
>+		XE_GUC_ACTION_GLOBAL_SCHED_POLICY_CHANGE,
>+		policy_offset
>+	};
>+
>+	return xe_guc_ct_send(ct, action, ARRAY_SIZE(action), 0, 0);
>+}
>+
>+int xe_guc_ads_scheduler_policy_disable_reset(struct xe_guc_ads *ads)
>+{
>+	struct xe_device *xe = ads_to_xe(ads);
>+	struct xe_gt *gt = ads_to_gt(ads);
>+	struct xe_tile *tile = gt_to_tile(gt);
>+	struct guc_policies *policies;
>+	struct xe_bo *bo;
>+	int ret = 0;
>+
>+	policies = kmalloc(sizeof(*policies), GFP_KERNEL);
>+	if (!policies)
>+		return -ENOMEM;
>+
>+	policies->dpc_promote_time = ads_blob_read(ads, policies.dpc_promote_time);
>+	policies->max_num_work_items = ads_blob_read(ads, policies.max_num_work_items);
>+	policies->is_valid = 1;
>+	if (xe->busted.mode == 2)
>+		policies->global_flags |= GLOBAL_POLICY_DISABLE_ENGINE_RESET;
>+
>+	bo = xe_managed_bo_create_from_data(xe, tile, policies, sizeof(struct guc_policies),
>+					    XE_BO_CREATE_VRAM_IF_DGFX(tile) |
>+					    XE_BO_CREATE_GGTT_BIT);
>+	if (IS_ERR(bo)) {
>+		ret = PTR_ERR(bo);
>+		goto out;
>+	}
>+
>+	ret = guc_ads_action_update_policies(ads, xe_bo_ggtt_addr(bo));
>+out:
>+	kfree(policies);
>+	return ret;
>+}
>diff --git a/drivers/gpu/drm/xe/xe_guc_ads.h b/drivers/gpu/drm/xe/xe_guc_ads.h
>index 138ef6267671..7c45c40fab34 100644
>--- a/drivers/gpu/drm/xe/xe_guc_ads.h
>+++ b/drivers/gpu/drm/xe/xe_guc_ads.h
>@@ -13,5 +13,6 @@ int xe_guc_ads_init_post_hwconfig(struct xe_guc_ads *ads);
> void xe_guc_ads_populate(struct xe_guc_ads *ads);
> void xe_guc_ads_populate_minimal(struct xe_guc_ads *ads);
> void xe_guc_ads_populate_post_load(struct xe_guc_ads *ads);
>+int xe_guc_ads_scheduler_policy_disable_reset(struct xe_guc_ads *ads);
>
> #endif
>-- 
>2.44.0
>