venus: TLS ring

This change adds a new venus feature: TLS ring
- co-owned by TLS and VkInstance
- initialized in TLS upon requested
- teardown happens upon thread exit or instance destroy
- teardown is split into 2 stages:
  1. one owner locks and destroys the ring and mark destroyed
  2. the other owner locks and frees up the tls ring storage

TLS ring supercedes the prior secondary ring and enables multi-thread
shader compilation and reduces the loading time of ROTTR from ~110s to
~21s (native is ~19s).

TLS ring is in fact a synchronous ring by design, and can be used to
redirect all exisiting synchronous submissions trivially. e.g. upon any
vn_call_*, request a TLS ring, wait for deps and then submit.

Signed-off-by: Yiwei Zhang <zzyiwei@chromium.org>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/26838>

src/virtio/vulkan/vn_instance.c

@@ -118,6 +118,10 @@ vn_instance_fini_ring(struct vn_instance *instance)
 
    vn_watchdog_fini(&instance->ring.watchdog);
 
+   list_for_each_entry_safe(struct vn_tls_ring, tls_ring,
+                            &instance->ring.tls_rings, vk_head)
+      vn_tls_destroy_ring(tls_ring);
+
    vn_ring_destroy(instance->ring.ring);
 }
 
@@ -133,6 +137,8 @@ vn_instance_init_ring(struct vn_instance *instance)
    if (!instance->ring.ring)
       return VK_ERROR_OUT_OF_HOST_MEMORY;
 
+   list_inithead(&instance->ring.tls_rings);
+
    vn_watchdog_init(&instance->ring.watchdog);
 
    mtx_init(&instance->ring.roundtrip_mutex, mtx_plain);