On 25 May 2017 at 03:25, Jason Ekstrand <jason at jlekstrand.net> wrote: > On Wed, May 24, 2017 at 12:06 AM, Dave Airlie <airlied at gmail.com> wrote: >> >> From: Dave Airlie <airlied at redhat.com> >> >> This interface will allow sync object to be used to back >> Vulkan fences. This API is pretty much the vulkan fence waiting >> API, and I've ported the code from amdgpu. >> >> v2: accept relative timeout, pass remaining time back >> to userspace. >> v3: return to absolute timeouts. >> >> Signed-off-by: Dave Airlie <airlied at redhat.com> >> --- >> drivers/gpu/drm/drm_internal.h | 2 + >> drivers/gpu/drm/drm_ioctl.c | 2 + >> drivers/gpu/drm/drm_syncobj.c | 164 >> +++++++++++++++++++++++++++++++++++++++++ >> include/uapi/drm/drm.h | 14 ++++ >> 4 files changed, 182 insertions(+) >> >> diff --git a/drivers/gpu/drm/drm_internal.h >> b/drivers/gpu/drm/drm_internal.h >> index 3fdef2c..53e3f6b 100644 >> --- a/drivers/gpu/drm/drm_internal.h >> +++ b/drivers/gpu/drm/drm_internal.h >> @@ -156,3 +156,5 @@ int drm_syncobj_handle_to_fd_ioctl(struct drm_device >> *dev, void *data, >> struct drm_file *file_private); >> int drm_syncobj_fd_to_handle_ioctl(struct drm_device *dev, void *data, >> struct drm_file *file_private); >> +int drm_syncobj_wait_ioctl(struct drm_device *dev, void *data, >> + struct drm_file *file_private); >> diff --git a/drivers/gpu/drm/drm_ioctl.c b/drivers/gpu/drm/drm_ioctl.c >> index f1e5681..385ce74 100644 >> --- a/drivers/gpu/drm/drm_ioctl.c >> +++ b/drivers/gpu/drm/drm_ioctl.c >> @@ -657,6 +657,8 @@ static const struct drm_ioctl_desc drm_ioctls[] = { >> DRM_UNLOCKED|DRM_RENDER_ALLOW), >> DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_FD_TO_HANDLE, >> drm_syncobj_fd_to_handle_ioctl, >> DRM_UNLOCKED|DRM_RENDER_ALLOW), >> + DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_WAIT, drm_syncobj_wait_ioctl, >> + DRM_UNLOCKED|DRM_RENDER_ALLOW), >> }; >> >> #define DRM_CORE_IOCTL_COUNT ARRAY_SIZE( drm_ioctls ) >> diff --git a/drivers/gpu/drm/drm_syncobj.c b/drivers/gpu/drm/drm_syncobj.c >> index b611480..8b87594 100644 >> --- a/drivers/gpu/drm/drm_syncobj.c >> +++ b/drivers/gpu/drm/drm_syncobj.c >> @@ -1,5 +1,7 @@ >> /* >> * Copyright 2017 Red Hat >> + * Parts ported from amdgpu (fence wait code). >> + * Copyright 2016 Advanced Micro Devices, Inc. >> * >> * Permission is hereby granted, free of charge, to any person obtaining >> a >> * copy of this software and associated documentation files (the >> "Software"), >> @@ -31,6 +33,9 @@ >> * that contain an optional fence. The fence can be updated with a new >> * fence, or be NULL. >> * >> + * syncobj's can be waited upon, where it will wait for the underlying >> + * fence. >> + * >> * syncobj's can be export to fd's and back, these fd's are opaque and >> * have no other use case, except passing the syncobj between processes. >> * >> @@ -375,3 +380,162 @@ drm_syncobj_fd_to_handle_ioctl(struct drm_device >> *dev, void *data, >> return drm_syncobj_fd_to_handle(file_private, args->fd, >> &args->handle); >> } >> + >> + >> +/** >> + * drm_timeout_abs_to_jiffies - calculate jiffies timeout from absolute >> value >> + * >> + * @timeout_ns: timeout in ns >> + * >> + * Calculate the timeout in jiffies from an absolute timeout in ns. >> + */ >> +unsigned long drm_timeout_abs_to_jiffies(uint64_t timeout_ns) >> +{ >> + unsigned long timeout_jiffies; >> + ktime_t timeout; >> + >> + /* clamp timeout if it's to large */ >> + if (((int64_t)timeout_ns) < 0) >> + return MAX_SCHEDULE_TIMEOUT; >> + >> + timeout = ktime_sub(ns_to_ktime(timeout_ns), ktime_get()); >> + if (ktime_to_ns(timeout) < 0) >> + return 0; >> + >> + timeout_jiffies = nsecs_to_jiffies(ktime_to_ns(timeout)); >> + /* clamp timeout to avoid unsigned-> signed overflow */ >> + if (timeout_jiffies > MAX_SCHEDULE_TIMEOUT ) >> + return MAX_SCHEDULE_TIMEOUT - 1; >> + >> + return timeout_jiffies; >> +} >> + >> +static int drm_syncobj_wait_all_fences(struct drm_device *dev, >> + struct drm_file *file_private, >> + struct drm_syncobj_wait *wait, >> + uint32_t *handles) >> +{ >> + uint32_t i; >> + int ret; >> + unsigned long timeout = >> drm_timeout_abs_to_jiffies(wait->timeout_ns); >> + >> + for (i = 0; i < wait->count_handles; i++) { >> + struct dma_fence *fence; >> + >> + ret = drm_syncobj_fence_get(file_private, handles[i], >> + &fence); >> + if (ret) >> + return ret; >> + >> + if (!fence) >> + continue; >> + >> + ret = dma_fence_wait_timeout(fence, true, timeout); >> + >> + dma_fence_put(fence); >> + if (ret < 0) >> + return ret; >> + if (ret == 0) >> + break; >> + timeout = ret; >> + } >> + >> + wait->out_timeout_ns = jiffies_to_nsecs(ret); >> + wait->out_status = (ret > 0); >> + wait->first_signaled = 0; >> + return 0; >> +} >> + >> +static int drm_syncobj_wait_any_fence(struct drm_device *dev, >> + struct drm_file *file_private, >> + struct drm_syncobj_wait *wait, >> + uint32_t *handles) >> +{ >> + unsigned long timeout = >> drm_timeout_abs_to_jiffies(wait->timeout_ns); >> + struct dma_fence **array; >> + uint32_t i; >> + int ret; >> + uint32_t first = ~0; >> + >> + /* Prepare the fence array */ >> + array = kcalloc(wait->count_handles, >> + sizeof(struct dma_fence *), GFP_KERNEL); >> + >> + if (array == NULL) >> + return -ENOMEM; >> + >> + for (i = 0; i < wait->count_handles; i++) { >> + struct dma_fence *fence; >> + >> + ret = drm_syncobj_fence_get(file_private, handles[i], >> + &fence); >> + if (ret) >> + goto err_free_fence_array; >> + else if (fence) >> + array[i] = fence; >> + else { /* NULL, the fence has been already signaled */ >> + ret = 1; >> + goto out; >> + } >> + } >> + >> + ret = dma_fence_wait_any_timeout(array, wait->count_handles, true, >> timeout, >> + &first); >> + if (ret < 0) >> + goto err_free_fence_array; >> +out: >> + wait->out_timeout_ns = jiffies_to_nsecs(ret); >> + wait->out_status = (ret > 0); >> + wait->first_signaled = first; >> + /* set return value 0 to indicate success */ >> + ret = 0; >> + >> +err_free_fence_array: >> + for (i = 0; i < wait->count_handles; i++) >> + dma_fence_put(array[i]); >> + kfree(array); >> + >> + return ret; >> +} >> + >> +int >> +drm_syncobj_wait_ioctl(struct drm_device *dev, void *data, >> + struct drm_file *file_private) >> +{ >> + struct drm_syncobj_wait *args = data; >> + uint32_t *handles; >> + int ret = 0; >> + >> + if (!drm_core_check_feature(dev, DRIVER_SYNCOBJ)) >> + return -ENODEV; >> + >> + if (args->flags != 0 && args->flags != >> DRM_SYNCOBJ_WAIT_FLAGS_WAIT_ALL) >> + return -EINVAL; >> + >> + if (args->count_handles == 0) >> + return 0; >> + >> + /* Get the handles from userspace */ >> + handles = kmalloc_array(args->count_handles, sizeof(uint32_t), >> + GFP_KERNEL); >> + if (handles == NULL) >> + return -ENOMEM; >> + >> + if (copy_from_user(handles, >> + (void __user *)(unsigned long)(args->handles), >> + sizeof(uint32_t) * args->count_handles)) { >> + ret = -EFAULT; >> + goto err_free_handles; >> + } >> + >> + if (args->flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_ALL) >> + ret = drm_syncobj_wait_all_fences(dev, file_private, >> + args, handles); >> + else >> + ret = drm_syncobj_wait_any_fence(dev, file_private, >> + args, handles); >> +err_free_handles: >> + kfree(handles); >> + >> + return ret; >> +} >> diff --git a/include/uapi/drm/drm.h b/include/uapi/drm/drm.h >> index 96c5c78..d6e2f62 100644 >> --- a/include/uapi/drm/drm.h >> +++ b/include/uapi/drm/drm.h >> @@ -716,6 +716,19 @@ struct drm_syncobj_handle { >> __u32 pad; >> }; >> >> +#define DRM_SYNCOBJ_WAIT_FLAGS_WAIT_ALL (1 << 0) >> +struct drm_syncobj_wait { >> + __u64 handles; >> + /* absolute timeout */ >> + __u64 timeout_ns; >> + /* remaining timeout */ >> + __u64 out_timeout_ns; > > > Any particular reason why we don't just make timeout_ns an in/out? I don't > really care and haven't given it much thought; mostly just curious. Timeout's are absolute, so if you replace the in timeout with a new value, and get -ERESTARTSYS, then you'd restart the ioctl with the wrong value. Dave.