Am 10.04.2017 um 09:18 schrieb Monk Liu: > sequence is protected by spinlock so don't access sequence > in paramter seq when invoking this function. > > ~0 means to get the latest sequence number and 0 means none to > get. > > Change-Id: Ib7a03f3cf5594deeb4ad333cc59b47a6bddfd1ad > Signed-off-by: Monk Liu <Monk.Liu at amd.com> > --- > drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c > index 6d86eae..71d5f25 100644 > --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c > +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ctx.c > @@ -277,6 +277,13 @@ struct fence *amdgpu_ctx_get_fence(struct amdgpu_ctx *ctx, > > spin_lock(&ctx->ring_lock); > > + if (seq == ~0) { That must be ~0ull, otherwise you would be checking a 32bit value here. Additional to that please define something in amdgpu_drm.h for that value. > + seq = ctx->rings[ring->idx].sequence - 1; > + } else if(seq == 0) { > + spin_unlock(&ctx->ring_lock); > + return NULL; > + } > + That is unnecessary the "if (seq + amdgpu_sched_jobs < cring->sequence) {" will catch this case. Regards, Christian. > if (seq >= cring->sequence) { > spin_unlock(&ctx->ring_lock); > return ERR_PTR(-EINVAL);