prefault is stll enabled by default which prevent most of pwrite/pread/reloc
from running slow path, in order to verify these slow pathes, prefault need
to be disabled.
Signed-off-by: Xiong Zhang <xiong.y.zh...@intel.com>
---
drivers/gpu/drm/i915/i915_drv.c | 5 +++++
drivers/gpu/drm/i915/i915_drv.h | 1 +
drivers/gpu/drm/i915/i915_gem.c | 12 +++++++-----
drivers/gpu/drm/i915/i915_gem_execbuffer.c | 6 ++++--
4 files changed, 17 insertions(+), 7 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
index b07362f..dac6bd3 100644
--- a/drivers/gpu/drm/i915/i915_drv.c
+++ b/drivers/gpu/drm/i915/i915_drv.c
@@ -137,6 +137,11 @@ module_param_named(fastboot, i915_fastboot, bool, 0600);
MODULE_PARM_DESC(fastboot, "Try to skip unnecessary mode sets at boot time "
"(default: false)");
+bool i915_prefault_disable __read_mostly = false;
+module_param_named(prefault_disable, i915_prefault_disable, bool, 0600);
+MODULE_PARM_DESC(prefault_disable,
+ "Try to disable pre page fault for pread/pwrite/reloc
(default:false)");
+
static struct drm_driver driver;
extern int intel_agp_enabled;
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 7fdc8e3..9516e19 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -1587,6 +1587,7 @@ extern unsigned int i915_preliminary_hw_support
__read_mostly;
extern int i915_disable_power_well __read_mostly;
extern int i915_enable_ips __read_mostly;
extern bool i915_fastboot __read_mostly;
+extern bool i915_prefault_disable __read_mostly;
extern int i915_suspend(struct drm_device *dev, pm_message_t state);
extern int i915_resume(struct drm_device *dev);
diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index c9d9d20..de59154 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -465,7 +465,7 @@ i915_gem_shmem_pread(struct drm_device *dev,
mutex_unlock(&dev->struct_mutex);
- if (!prefaulted) {
+ if (likely(!i915_prefault_disable) && !prefaulted) {
ret = fault_in_multipages_writeable(user_data, remain);
/* Userspace is tricking us, but we've already clobbered
* its pages with the prefault and promised to write the
@@ -860,10 +860,12 @@ i915_gem_pwrite_ioctl(struct drm_device *dev, void *data,
args->size))
return -EFAULT;
- ret = fault_in_multipages_readable(to_user_ptr(args->data_ptr),
- args->size);
- if (ret)
- return -EFAULT;
+ if (likely(!i915_prefault_disable)) {
+ ret = fault_in_multipages_readable(to_user_ptr(args->data_ptr),
+ args->size);
+ if (ret)
+ return -EFAULT;
+ }
ret = i915_mutex_lock_interruptible(dev);
if (ret)
diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c
b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
index 1b58694..1734825 100644
--- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c
+++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
@@ -759,8 +759,10 @@ validate_exec_list(struct drm_i915_gem_exec_object2 *exec,
if (!access_ok(VERIFY_WRITE, ptr, length))
return -EFAULT;
- if (fault_in_multipages_readable(ptr, length))
- return -EFAULT;
+ if (likely(!i915_prefault_disable)) {
+ if (fault_in_multipages_readable(ptr, length))
+ return -EFAULT;
+ }
}
return 0;
--
1.8.3.2
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
http://lists.freedesktop.org/mailman/listinfo/intel-gfx
