[Intel-gfx] [PATCH v2] drm/i915: Mark i915.inject_load_failure as being hit

[Chris Wilson]

When we reach the magic value and do inject a fault into our module load,
mark the module option as being hit. Since we fail from inside pci
probe, the module load isn't actually aborted and the module (and
paramters) are left lingering. igt can then inspect the parameter on its
synchronous completion of modprobe to see if the fault injection was
successful, and will keeping on injecting new faults until the module
succeeds in loading having surpassed the number of fault points.

v2: Reset to 0 after being hit;

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
Cc: Michał Winiarski <michal.winiarski at intel.com>
Cc: Imre Deak <imre.deak at intel.com>
---
 drivers/gpu/drm/i915/i915_drv.c | 19 ++++++-------------
 1 file changed, 6 insertions(+), 13 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index 6b599b1837dc..f7653e738e46 100644
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -58,6 +58,7 @@ static struct drm_driver driver;
 
 #if IS_ENABLED(CONFIG_DRM_I915_DEBUG)
 static unsigned int i915_load_fail_count;
+static int i915_load_error_level = KERN_ERR;
 
 bool __i915_inject_load_failure(const char *func, int line)
 {
@@ -67,11 +68,15 @@ bool __i915_inject_load_failure(const char *func, int line)
 	if (++i915_load_fail_count == i915_modparams.inject_load_failure) {
 		DRM_INFO("Injecting failure at checkpoint %u [%s:%d]\n",
 			 i915_modparams.inject_load_failure, func, line);
+		i915_modparams.inject_load_failure = 0;
+		i915_load_error_level = KERN_DEBUG;
 		return true;
 	}
 
 	return false;
 }
+#else
+#define i915_load_error_level KERN_ERR
 #endif
 
 #define FDO_BUG_URL "https://bugs.freedesktop.org/enter_bug.cgi?product=DRI"
@@ -114,20 +119,8 @@ __i915_printk(struct drm_i915_private *dev_priv, const char *level,
 	va_end(args);
 }
 
-static bool i915_error_injected(struct drm_i915_private *dev_priv)
-{
-#if IS_ENABLED(CONFIG_DRM_I915_DEBUG)
-	return i915_modparams.inject_load_failure &&
-	       i915_load_fail_count == i915_modparams.inject_load_failure;
-#else
-	return false;
-#endif
-}
-
 #define i915_load_error(dev_priv, fmt, ...)				     \
-	__i915_printk(dev_priv,						     \
-		      i915_error_injected(dev_priv) ? KERN_DEBUG : KERN_ERR, \
-		      fmt, ##__VA_ARGS__)
+	__i915_printk(dev_priv, i915_load_error_level, fmt, ##__VA_ARGS__)
 
 /* Map PCH device id to PCH type, or PCH_NONE if unknown. */
 static enum intel_pch
-- 
2.17.1