From 0b74b508f78cea96d0d1b47e72cc0ec7959cdc68 Mon Sep 17 00:00:00 2001 From: Xiong Zhang Date: Fri, 19 Jul 2013 13:51:24 +0800 Subject: [PATCH] drm/i915: add prefault_disable module option 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 [danvet: Make checkpatch happy and bikeshed the module option help text a bit.] Signed-off-by: Daniel Vetter --- 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 b178a7ca1294..c34086ad8181 100644 --- a/drivers/gpu/drm/i915/i915_drv.c +++ b/drivers/gpu/drm/i915/i915_drv.c @@ -141,6 +141,11 @@ 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; +module_param_named(prefault_disable, i915_prefault_disable, bool, 0600); +MODULE_PARM_DESC(prefault_disable, + "Disable page prefaulting for pread/pwrite/reloc (default:false). For developers only."); + 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 36d1c806e092..fc32d2034f38 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -1627,6 +1627,7 @@ 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 ce043f14eab9..acc99d458143 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 1b58694d7be7..1734825bef34 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;