From: Axel Davy <axel.davy@ens.fr>
Date: Wed, 15 Mar 2017 21:45:03 +0000 (+0100)
Subject: st/nine: Resolve deadlock in surface/volume dtors when using csmt
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=bd85bb51c717a1858157c73adcb689e3986b2134;p=mesa.git

st/nine: Resolve deadlock in surface/volume dtors when using csmt

Surfaces and Volumes can be freed in the worker thread.

Without this patch, pending_uploads_counter could be non-zero
in the Surfaces or Volumes dtor, leading to deadlock.
Instead decrease properly the counter before releasing the
item.

Also avoid another potential deadlock if the item is not
properly unlocked: Do not call UnlockRect which will cause deadlock,
but free directly using the deadlock safe
nine_context_get_pipe_multithread.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=99246

CC: "17.0" <mesa-stable@lists.freedesktop.org>
Signed-off-by: Axel Davy <axel.davy@ens.fr>
Tested-by: James Harvey <lothmordor@gmail.com>
---

diff --git a/src/gallium/state_trackers/nine/nine_csmt_helper.h b/src/gallium/state_trackers/nine/nine_csmt_helper.h
index b0bbc054fc3..dc46bbd3a28 100644
--- a/src/gallium/state_trackers/nine/nine_csmt_helper.h
+++ b/src/gallium/state_trackers/nine/nine_csmt_helper.h
@@ -233,8 +233,8 @@ name##_rx( struct NineDevice9 *device, struct csmt_instruction *instr ) \
     name##_priv( \
         device ARGS_FOR_CALL( __VA_ARGS__ ) \
     ); \
-    ARGS_FOR_UNBIND( __VA_ARGS__ ) \
     p_atomic_dec(args->counter); \
+    ARGS_FOR_UNBIND( __VA_ARGS__ ) \
     return 0; \
 } \
 \
diff --git a/src/gallium/state_trackers/nine/surface9.c b/src/gallium/state_trackers/nine/surface9.c
index 836369cafdb..d917fa1f868 100644
--- a/src/gallium/state_trackers/nine/surface9.c
+++ b/src/gallium/state_trackers/nine/surface9.c
@@ -204,9 +204,15 @@ NineSurface9_dtor( struct NineSurface9 *This )
 {
     DBG("This=%p\n", This);
 
-    if (This->transfer)
-        NineSurface9_UnlockRect(This);
+    if (This->transfer) {
+        struct pipe_context *pipe = nine_context_get_pipe_multithread(This->base.base.device);
+        pipe->transfer_unmap(pipe, This->transfer);
+        This->transfer = NULL;
+    }
 
+    /* Note: Following condition cannot happen currently, since we
+     * refcount the surface in the functions increasing
+     * pending_uploads_counter. */
     if (p_atomic_read(&This->pending_uploads_counter))
         nine_csmt_process(This->base.base.device);
 
diff --git a/src/gallium/state_trackers/nine/volume9.c b/src/gallium/state_trackers/nine/volume9.c
index 11236a02e75..62af3e62251 100644
--- a/src/gallium/state_trackers/nine/volume9.c
+++ b/src/gallium/state_trackers/nine/volume9.c
@@ -142,9 +142,15 @@ NineVolume9_dtor( struct NineVolume9 *This )
 {
     DBG("This=%p\n", This);
 
-    if (This->transfer)
-        NineVolume9_UnlockBox(This);
+    if (This->transfer) {
+        struct pipe_context *pipe = nine_context_get_pipe_multithread(This->base.device);
+        pipe->transfer_unmap(pipe, This->transfer);
+        This->transfer = NULL;
+    }
 
+    /* Note: Following condition cannot happen currently, since we
+     * refcount the volume in the functions increasing
+     * pending_uploads_counter. */
     if (p_atomic_read(&This->pending_uploads_counter))
         nine_csmt_process(This->base.device);