I'm working on a VK_KHR_external_fence implementation based on this and have found some issues. :-) On Mon, Jul 17, 2017 at 11:44 PM, Dave Airlie wrote: > From: Dave Airlie > > 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. > v4: absolute zero = poll, > rewrite any/all code to have same operation for arrays > return -EINVAL for 0 fences. > v4.1: fixup fences allocation check, use u64_to_user_ptr > v5: move to sec/nsec, and use timespec64 for calcs. > v6: use -ETIME and drop the out status flag. (-ETIME > is suggested by ickle, I can feel a shed painting) > v7: talked to Daniel/Arnd, use ktime and ns everywhere. > > Signed-off-by: Dave Airlie > --- > drivers/gpu/drm/drm_internal.h | 2 + > drivers/gpu/drm/drm_ioctl.c | 2 + > drivers/gpu/drm/drm_syncobj.c | 135 ++++++++++++++++++++++++++++++ > +++++++++++ > include/uapi/drm/drm.h | 12 ++++ > 4 files changed, 151 insertions(+) > > diff --git a/drivers/gpu/drm/drm_internal.h b/drivers/gpu/drm/drm_internal > .h > index 5cecc97..d71b50d 100644 > --- a/drivers/gpu/drm/drm_internal.h > +++ b/drivers/gpu/drm/drm_internal.h > @@ -157,3 +157,5 @@ 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 89441bc..d23dcc6 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. > * > @@ -451,3 +456,133 @@ 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_sec: timeout sec component, 0 for poll > + * @timeout_nsec: timeout nsec component in ns, 0 for poll > + * both must be 0 for poll. > + * > + * Calculate the timeout in jiffies from an absolute time in sec/nsec. > + */ > +static unsigned long drm_timeout_abs_to_jiffies(int64_t timeout_nsec) > +{ > + ktime_t abs_timeout, timeout, max_jiffy_ktime; > + unsigned long timeout_jiffies; > + > + /* make 0 timeout means poll - absolute 0 doesn't seem valid */ > + if (timeout_nsec == 0) > + return 0; > + > + abs_timeout = ns_to_ktime(timeout_nsec); > + > + timeout = ktime_sub(abs_timeout, ktime_get()); > This can end you up with a negative timeout. dma_fence_wait_timeout will WARN_ON a negative timeout. > + > + max_jiffy_ktime = ns_to_ktime(jiffies_to_nsecs(MAX_JIFFY_OFFSET)); > + if (ktime_compare(timeout, max_jiffy_ktime)) > I think you want a > 0 here because otherwise this is a "!=" comparison which isn't what you want. Either that or use ktime_after(). > + return MAX_SCHEDULE_TIMEOUT - 1; > + > + timeout_jiffies = nsecs_to_jiffies(ktime_to_ns(timeout)); > + /* clamp timeout to avoid infinite timeout */ > + if (timeout_jiffies >= MAX_SCHEDULE_TIMEOUT) > + return MAX_SCHEDULE_TIMEOUT - 1; > + > + return timeout_jiffies + 1; > +} > + > +static int drm_syncobj_wait_fences(struct drm_device *dev, > + struct drm_file *file_private, > + struct drm_syncobj_wait *wait, > + struct dma_fence **fences) > +{ > + unsigned long timeout = drm_timeout_abs_to_jiffies(wai > t->timeout_nsec); > + int ret = 0; > + uint32_t first = ~0; > + > + if (wait->flags & DRM_SYNCOBJ_WAIT_FLAGS_WAIT_ALL) { > + int i; > + for (i = 0; i < wait->count_handles; i++) { > + ret = dma_fence_wait_timeout(fences[i], true, > timeout); > Various dma_fence callbacks (including, aparently, i915) return -ENOENT to indicate that the fence has already been signaled. We need to sanitize that to 0 or else we'll return early. > + > + if (ret < 0) > + return ret; > + if (ret == 0) > + break; > + timeout = ret; > + } > + first = 0; > + } else { > + ret = dma_fence_wait_any_timeout(fences, > + wait->count_handles, > + true, timeout, > + &first); > + } > + > + if (ret < 0) > + return ret; > + > + wait->first_signaled = first; > + if (ret == 0) > + return -ETIME; > + return 0; > +} > + > +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; > + struct dma_fence **fences; > + int ret = 0; > + int i; > + > + 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 -EINVAL; > + > + /* 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, > + u64_to_user_ptr(args->handles), > + sizeof(uint32_t) * args->count_handles)) { > + ret = -EFAULT; > + goto err_free_handles; > + } > + > + fences = kcalloc(args->count_handles, > + sizeof(struct dma_fence *), GFP_KERNEL); > + if (!fences) { > + ret = -ENOMEM; > + goto err_free_handles; > + } > + > + for (i = 0; i < args->count_handles; i++) { > + ret = drm_syncobj_fence_get(file_private, handles[i], > + &fences[i]); > + if (ret) > + goto err_free_fence_array; > + } > + > + ret = drm_syncobj_wait_fences(dev, file_private, > + args, fences); > + > +err_free_fence_array: > + for (i = 0; i < args->count_handles; i++) > + dma_fence_put(fences[i]); > + kfree(fences); > +err_free_handles: > + kfree(handles); > + > + return ret; > +} > diff --git a/include/uapi/drm/drm.h b/include/uapi/drm/drm.h > index 101593a..0757c1a 100644 > --- a/include/uapi/drm/drm.h > +++ b/include/uapi/drm/drm.h > @@ -718,6 +718,17 @@ struct drm_syncobj_handle { > __u32 pad; > }; > > +#define DRM_SYNCOBJ_WAIT_FLAGS_WAIT_ALL (1 << 0) > +struct drm_syncobj_wait { > + __u64 handles; > + /* absolute timeout */ > + __s64 timeout_nsec; > + __u32 count_handles; > + __u32 flags; > + __u32 first_signaled; /* only valid when not waiting all */ > + __u32 pad; > +}; > + > #if defined(__cplusplus) > } > #endif > @@ -840,6 +851,7 @@ extern "C" { > #define DRM_IOCTL_SYNCOBJ_DESTROY DRM_IOWR(0xC0, struct > drm_syncobj_destroy) > #define DRM_IOCTL_SYNCOBJ_HANDLE_TO_FD DRM_IOWR(0xC1, struct > drm_syncobj_handle) > #define DRM_IOCTL_SYNCOBJ_FD_TO_HANDLE DRM_IOWR(0xC2, struct > drm_syncobj_handle) > +#define DRM_IOCTL_SYNCOBJ_WAIT DRM_IOWR(0xC3, struct > drm_syncobj_wait) > > /** > * Device specific ioctls should only be in their respective headers > -- > 2.9.4 > > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/dri-devel >