Quoting Tvrtko Ursulin (2019-07-08 13:10:34) > > On 08/07/2019 12:19, Chris Wilson wrote: > > Avoid a global idle barrier by reconfiguring each context by rewriting > > them with MI_STORE_DWORD from the kernel context. > > > > v2: We only need to determine the desired register values once, they are > > the same for all contexts. > > > > Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> > > Cc: Lionel Landwerlin <lionel.g.landwerlin@xxxxxxxxx> > > Cc: Tvrtko Ursulin <tvrtko.ursulin@xxxxxxxxx> > > Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@xxxxxxxxx> > > --- > > drivers/gpu/drm/i915/gem/i915_gem_context.c | 2 + > > drivers/gpu/drm/i915/gt/intel_lrc.c | 7 +- > > drivers/gpu/drm/i915/i915_perf.c | 248 +++++++++++++++----- > > 3 files changed, 195 insertions(+), 62 deletions(-) > > > > diff --git a/drivers/gpu/drm/i915/gem/i915_gem_context.c b/drivers/gpu/drm/i915/gem/i915_gem_context.c > > index e367dce2a696..1f0d10bb88c1 100644 > > --- a/drivers/gpu/drm/i915/gem/i915_gem_context.c > > +++ b/drivers/gpu/drm/i915/gem/i915_gem_context.c > > @@ -624,7 +624,9 @@ i915_gem_context_create_kernel(struct drm_i915_private *i915, int prio) > > ctx->sched.priority = I915_USER_PRIORITY(prio); > > ctx->ring_size = PAGE_SIZE; > > > > + /* Isolate the kernel context from prying eyes and sticky fingers */ > > GEM_BUG_ON(!i915_gem_context_is_kernel(ctx)); > > + list_del_init(&ctx->link); > > Why exactly? Otherwise we recursively try to modify the context. > Any repercussions for i915_sysfs/i915_l3_write? debugfs I gather you > won't care about? No, because what matters for those is user contexts. > Should adding to i915->contexts.list be done from gem_context_register? > What remains not a kernel context, but on a list? And I also plan to pull it under its own mutex. > Won't preempt context be missed in re-configuration? What preempt-context? :-p And I would skip kernel_context if I could, but for whatever reason oa events are being sent to userspace even while the GPU is idle and igt expects the regular tick. -Chris _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
