st/wgl: re-implement stw_device::ctx_mutex with CRITICAL_SECTION

This is Windows-only code so we can use the native Win32 functions for
critical sections.  This will also allow us to (cleanly) add some mutex
check/debug code in subsequent patches.

Reviewed-by: Sinclair Yeh <[email protected]>
Reviewed-by: Charmaine Lee <[email protected]>

3 files changed, 34 insertions, 19 deletions

diff --git a/src/gallium/state_trackers/wgl/stw_context.c b/src/gallium/state_trackers/wgl/stw_context.c
index 0f859649217..229fdfd1625 100644
--- a/src/gallium/state_trackers/wgl/stw_context.c
+++ b/src/gallium/state_trackers/wgl/stw_context.c
@@ -70,7 +70,7 @@ DrvCopyContext(DHGLRC dhrcSource, DHGLRC dhrcDest, UINT fuMask)
    if (!stw_dev)
       return FALSE;
 
-   pipe_mutex_lock( stw_dev->ctx_mutex );
+   stw_lock_contexts(stw_dev);
 
    src = stw_lookup_context_locked( dhrcSource );
    dst = stw_lookup_context_locked( dhrcDest );
@@ -83,7 +83,7 @@ DrvCopyContext(DHGLRC dhrcSource, DHGLRC dhrcDest, UINT fuMask)
       (void) fuMask;
    }
 
-   pipe_mutex_unlock( stw_dev->ctx_mutex );
+   stw_unlock_contexts(stw_dev);
 
    return ret;
 }
@@ -99,7 +99,7 @@ DrvShareLists(DHGLRC dhglrc1, DHGLRC dhglrc2)
    if (!stw_dev)
       return FALSE;
 
-   pipe_mutex_lock( stw_dev->ctx_mutex );
+   stw_lock_contexts(stw_dev);
 
    ctx1 = stw_lookup_context_locked( dhglrc1 );
    ctx2 = stw_lookup_context_locked( dhglrc2 );
@@ -107,7 +107,7 @@ DrvShareLists(DHGLRC dhglrc1, DHGLRC dhglrc2)
    if (ctx1 && ctx2 && ctx2->st->share)
       ret = ctx2->st->share(ctx2->st, ctx1->st);
 
-   pipe_mutex_unlock( stw_dev->ctx_mutex );
+   stw_unlock_contexts(stw_dev);
 
    return ret;
 }
@@ -173,9 +173,9 @@ stw_create_context_attribs(HDC hdc, INT iLayerPlane, DHGLRC hShareContext,
    pfi = stw_pixelformat_get_info( iPixelFormat );
 
    if (hShareContext != 0) {
-      pipe_mutex_lock( stw_dev->ctx_mutex );
+      stw_lock_contexts(stw_dev);
       shareCtx = stw_lookup_context_locked( hShareContext );
-      pipe_mutex_unlock( stw_dev->ctx_mutex );
+      stw_unlock_contexts(stw_dev);
    }
 
    ctx = CALLOC_STRUCT( stw_context );
@@ -250,7 +250,7 @@ stw_create_context_attribs(HDC hdc, INT iLayerPlane, DHGLRC hShareContext,
       ctx->hud = hud_create(ctx->st->pipe, ctx->st->cso_context);
    }
 
-   pipe_mutex_lock( stw_dev->ctx_mutex );
+   stw_lock_contexts(stw_dev);
    if (handle) {
       /* We're replacing the context data for this handle. See the
        * wglCreateContextAttribsARB() function.
@@ -276,7 +276,8 @@ stw_create_context_attribs(HDC hdc, INT iLayerPlane, DHGLRC hShareContext,
 
    ctx->dhglrc = handle;
 
-   pipe_mutex_unlock( stw_dev->ctx_mutex );
+   stw_unlock_contexts(stw_dev);
+
    if (!ctx->dhglrc)
       goto no_hglrc;
 
@@ -303,10 +304,10 @@ DrvDeleteContext(DHGLRC dhglrc)
    if (!stw_dev)
       return FALSE;
 
-   pipe_mutex_lock( stw_dev->ctx_mutex );
+   stw_lock_contexts(stw_dev);
    ctx = stw_lookup_context_locked(dhglrc);
    handle_table_remove(stw_dev->ctx_table, dhglrc);
-   pipe_mutex_unlock( stw_dev->ctx_mutex );
+   stw_unlock_contexts(stw_dev);
 
    if (ctx) {
       struct stw_context *curctx = stw_current_context();
@@ -337,9 +338,9 @@ DrvReleaseContext(DHGLRC dhglrc)
    if (!stw_dev)
       return FALSE;
 
-   pipe_mutex_lock( stw_dev->ctx_mutex );
+   stw_lock_contexts(stw_dev);
    ctx = stw_lookup_context_locked( dhglrc );
-   pipe_mutex_unlock( stw_dev->ctx_mutex );
+   stw_unlock_contexts(stw_dev);
 
    if (!ctx)
       return FALSE;
@@ -408,9 +409,9 @@ stw_make_current(HDC hdc, DHGLRC dhglrc)
    }
 
    if (dhglrc) {
-      pipe_mutex_lock( stw_dev->ctx_mutex );
+      stw_lock_contexts(stw_dev);
       ctx = stw_lookup_context_locked( dhglrc );
-      pipe_mutex_unlock( stw_dev->ctx_mutex );
+      stw_unlock_contexts(stw_dev);
       if (!ctx) {
          goto fail;
       }
diff --git a/src/gallium/state_trackers/wgl/stw_device.c b/src/gallium/state_trackers/wgl/stw_device.c
index 25b6341ecad..2f51fdb1cbf 100644
--- a/src/gallium/state_trackers/wgl/stw_device.c
+++ b/src/gallium/state_trackers/wgl/stw_device.c
@@ -106,7 +106,7 @@ stw_init(const struct stw_winsys *stw_winsys)
          screen->get_param(screen, PIPE_CAP_MAX_TEXTURE_2D_LEVELS);
    stw_dev->max_2d_length = 1 << (stw_dev->max_2d_levels - 1);
 
-   pipe_mutex_init( stw_dev->ctx_mutex );
+   InitializeCriticalSection(&stw_dev->ctx_mutex);
    pipe_mutex_init( stw_dev->fb_mutex );
 
    stw_dev->ctx_table = handle_table_create();
@@ -156,9 +156,9 @@ stw_cleanup(void)
     * Abort cleanup if there are still active contexts. In some situations
     * this DLL may be unloaded before the DLL that is using GL contexts is.
     */
-   pipe_mutex_lock( stw_dev->ctx_mutex );
+   stw_lock_contexts(stw_dev);
    dhglrc = handle_table_get_first_handle(stw_dev->ctx_table);
-   pipe_mutex_unlock( stw_dev->ctx_mutex );
+   stw_unlock_contexts(stw_dev);
    if (dhglrc) {
       debug_printf("%s: contexts still active -- cleanup aborted\n", __FUNCTION__);
       stw_dev = NULL;
@@ -170,7 +170,7 @@ stw_cleanup(void)
    stw_framebuffer_cleanup();
    
    pipe_mutex_destroy( stw_dev->fb_mutex );
-   pipe_mutex_destroy( stw_dev->ctx_mutex );
+   DeleteCriticalSection(&stw_dev->ctx_mutex);
    
    FREE(stw_dev->smapi);
    stw_dev->stapi->destroy(stw_dev->stapi);
diff --git a/src/gallium/state_trackers/wgl/stw_device.h b/src/gallium/state_trackers/wgl/stw_device.h
index e35a4b94036..f271762f6b1 100644
--- a/src/gallium/state_trackers/wgl/stw_device.h
+++ b/src/gallium/state_trackers/wgl/stw_device.h
@@ -65,7 +65,7 @@ struct stw_device
 
    GLCALLBACKTABLE callbacks;
 
-   pipe_mutex ctx_mutex;
+   CRITICAL_SECTION ctx_mutex;
    struct handle_table *ctx_table;
    
    pipe_mutex fb_mutex;
@@ -89,4 +89,18 @@ stw_lookup_context_locked( DHGLRC dhglrc )
 }
 
 
+static inline void
+stw_lock_contexts(struct stw_device *stw_dev)
+{
+   EnterCriticalSection(&stw_dev->ctx_mutex);
+}
+
+
+static inline void
+stw_unlock_contexts(struct stw_device *stw_dev)
+{
+   LeaveCriticalSection(&stw_dev->ctx_mutex);
+}
+
+
 #endif /* STW_DEVICE_H_ */