On Thu, 26 Sep 2024, Rodrigo Vivi rodrigo.vivi@intel.com wrote:
On Wed, Sep 18, 2024 at 08:35:43PM +0300, Jani Nikula wrote:
CONFIG_DRM_I915_USERFAULT_AUTOSUSPEND is an int, defaulting to 250. When the wakeref is non-zero, it's either -1 or a dynamically allocated pointer, depending on CONFIG_DRM_I915_DEBUG_RUNTIME_PM. It's likely that the code works by coincidence with the bitwise AND, but with CONFIG_DRM_I915_DEBUG_RUNTIME_PM=y, there's the off chance that the condition evaluates to false, and intel_wakeref_auto() doesn't get called. Switch to the intended logical AND.
v2: Use != to avoid clang -Wconstant-logical-operand (Nathan)
oh, this is ugly!
Wouldn't it be better then to use IS_ENABLED() macro?
It's an int config option, not a bool. (Yes, the name is misleading.)
IS_ENABLED(CONFIG_DRM_I915_USERFAULT_AUTOSUSPEND) would be the same as CONFIG_DRM_I915_USERFAULT_AUTOSUSPEND == 1.
We're actually checking if the int value != 0, so IMO the patch at hand is fine.
BR, Jani.
Fixes: ad74457a6b5a ("drm/i915/dgfx: Release mmap on rpm suspend") Cc: Matthew Auld matthew.auld@intel.com Cc: Rodrigo Vivi rodrigo.vivi@intel.com Cc: Anshuman Gupta anshuman.gupta@intel.com Cc: Andi Shyti andi.shyti@linux.intel.com Cc: Nathan Chancellor nathan@kernel.org Cc: stable@vger.kernel.org # v6.1+ Reviewed-by: Matthew Auld matthew.auld@intel.com # v1 Reviewed-by: Andi Shyti andi.shyti@linux.intel.com # v1 Signed-off-by: Jani Nikula jani.nikula@intel.com
drivers/gpu/drm/i915/gem/i915_gem_ttm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c index 5c72462d1f57..b22e2019768f 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_ttm.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_ttm.c @@ -1131,7 +1131,7 @@ static vm_fault_t vm_fault_ttm(struct vm_fault *vmf) GEM_WARN_ON(!i915_ttm_cpu_maps_iomem(bo->resource)); }
- if (wakeref & CONFIG_DRM_I915_USERFAULT_AUTOSUSPEND)
- if (wakeref && CONFIG_DRM_I915_USERFAULT_AUTOSUSPEND != 0) intel_wakeref_auto(&to_i915(obj->base.dev)->runtime_pm.userfault_wakeref, msecs_to_jiffies_timeout(CONFIG_DRM_I915_USERFAULT_AUTOSUSPEND));
2.39.2