int drm_intel_gem_bo_wait(drm_intel_bo *bo, uint64_t timeout_ns)
This should bump the libdrm version. We're waiting for context support so we can do both features in one bump.
v2: don't return remaining timeout amount use get param and fallback for older kernels
v3: only doing getparam at init prototypes now have a signed input value
v4: update comments fall back to correct polling behavior with new userspace and old kernel
v5: since the drmIoctl patch was not well received, return appropriate values in this function instead. As Daniel pointed out, the polling case (timeout == 0) should also return -ETIME.
Cc: Eric Anholt eric@anholt.net Cc: Daniel Vetter daniel.vetter@ffwll.ch Signed-off-by: Ben Widawsky ben@bwidawsk.net --- intel/intel_bufmgr.h | 1 + intel/intel_bufmgr_gem.c | 57 ++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 58 insertions(+)
diff --git a/intel/intel_bufmgr.h b/intel/intel_bufmgr.h index c197abc..fa6c4dd 100644 --- a/intel/intel_bufmgr.h +++ b/intel/intel_bufmgr.h @@ -184,6 +184,7 @@ int drm_intel_get_pipe_from_crtc_id(drm_intel_bufmgr *bufmgr, int crtc_id);
int drm_intel_get_aperture_sizes(int fd, size_t *mappable, size_t *total); int drm_intel_bufmgr_gem_get_devid(drm_intel_bufmgr *bufmgr); +int drm_intel_gem_bo_wait(drm_intel_bo *bo, int64_t timeout_ns);
/* drm_intel_bufmgr_fake.c */ drm_intel_bufmgr *drm_intel_bufmgr_fake_init(int fd, diff --git a/intel/intel_bufmgr_gem.c b/intel/intel_bufmgr_gem.c index b776d2f..e90f8bd 100644 --- a/intel/intel_bufmgr_gem.c +++ b/intel/intel_bufmgr_gem.c @@ -119,6 +119,7 @@ typedef struct _drm_intel_bufmgr_gem { unsigned int has_blt : 1; unsigned int has_relaxed_fencing : 1; unsigned int has_llc : 1; + unsigned int has_wait_timeout : 1; unsigned int bo_reuse : 1; unsigned int no_exec : 1; bool fenced_relocs; @@ -1479,6 +1480,58 @@ drm_intel_gem_bo_wait_rendering(drm_intel_bo *bo) }
/** + * Waits on a BO for the given amount of time. + * + * @bo: buffer object to wait for + * @timeout_ns: amount of time to wait in nanoseconds. + * If value is less than 0, an infinite wait will occur. + * + * Returns 0 if the wait was successful ie. the last batch referencing the + * object has completed within the allotted time. Otherwise some negative return + * value describes the error. Of particular interest is -ETIME when the wait has + * failed to yield the desired result. + * + * Similar to drm_intel_gem_bo_wait_rendering except a timeout parameter allows + * the operation to give up after a certain amount of time. Another subtle + * difference is the internal locking semantics are different (this variant does + * not hold the lock for the duration of the wait). This makes the wait subject + * to a larger userspace race window. + * + * The implementation shall wait until the object is no longer actively + * referenced within a batch buffer at the time of the call. The wait will + * not guarantee that the buffer is re-issued via another thread, or an flinked + * handle. Userspace must make sure this race does not occur if such precision + * is important. + */ +int drm_intel_gem_bo_wait(drm_intel_bo *bo, int64_t timeout_ns) +{ + drm_intel_bufmgr_gem *bufmgr_gem = (drm_intel_bufmgr_gem *) bo->bufmgr; + drm_intel_bo_gem *bo_gem = (drm_intel_bo_gem *) bo; + struct drm_i915_gem_wait wait; + int ret; + + if (!bufmgr_gem->has_wait_timeout) { + DBG("%s:%d: Timed wait is not supported. Falling back to " + "infinite wait\n", __FILE__, __LINE__); + if (timeout_ns) { + drm_intel_gem_bo_wait_rendering(bo); + return 0; + } else { + return drm_intel_gem_bo_busy(bo) ? -ETIME : 0; + } + } + + wait.bo_handle = bo_gem->gem_handle; + wait.timeout_ns = timeout_ns; + wait.flags = 0; + ret = drmIoctl(bufmgr_gem->fd, DRM_IOCTL_I915_GEM_WAIT, &wait); + if (ret == -1) + return -errno; + + return ret; +} + +/** * Sets the object to the GTT read and possibly write domain, used by the X * 2D driver in the absence of kernel support to do drm_intel_gem_bo_map_gtt(). * @@ -2898,6 +2951,10 @@ drm_intel_bufmgr_gem_init(int fd, int batch_size) ret = drmIoctl(bufmgr_gem->fd, DRM_IOCTL_I915_GETPARAM, &gp); bufmgr_gem->has_relaxed_fencing = ret == 0;
+ gp.param = I915_PARAM_HAS_WAIT_TIMEOUT; + ret = drmIoctl(bufmgr_gem->fd, DRM_IOCTL_I915_GETPARAM, &gp); + bufmgr_gem->has_wait_timeout = ret == 0; + gp.param = I915_PARAM_HAS_LLC; ret = drmIoctl(bufmgr_gem->fd, DRM_IOCTL_I915_GETPARAM, &gp); if (ret != 0) {