context: Avoid doing excessive work if application re-sets the same context

[fips] / context.c

diff --git a/context.c b/context.c
index f4694c1ae8052152c9d36383e64170ccca2a0832..284e4ae8d8e7ce246e37246fc616ad77b6d3713f 100644 (file)
--- a/context.c
+++ b/context.c
@@ -20,23 +20,46 @@
  */
 
 #include "context.h"
-
 #include "metrics.h"
+#include "xmalloc.h"
 
-/* FIXME: Need a map from integers to context objects and track the
- * current context with glXMakeContextCurrent, eglMakeCurrent, etc. */
-
-context_t current_context;
+context_t *current_context;
 
-void
-context_enter (fips_api_t api, void *system_context_id unused)
+static context_t *
+context_create (fips_api_t api, void *system_context_id)
 {
-       context_t *ctx = &current_context;
+       context_t *ctx;
+
+       ctx = xcalloc (1, sizeof (*ctx));
+
+       ctx->system_id = system_context_id;
 
        fips_dispatch_init (api);
 
        metrics_info_init (&ctx->metrics_info);
 
+       return ctx;
+}
+
+static void
+context_destroy (context_t *ctx)
+{
+       metrics_info_fini (&ctx->metrics_info);
+}
+
+void
+context_enter (fips_api_t api, void *system_context_id)
+{
+       /* Do nothing if the application is setting the same context
+        * as is already current. */
+       if (current_context && current_context->system_id == system_context_id)
+               return;
+
+       if (current_context)
+               context_destroy (current_context);
+
+       current_context = context_create (api, system_context_id);
+
        metrics_set_current_op (METRICS_OP_SHADER + 0);
        metrics_counter_start ();
 }
@@ -44,10 +67,13 @@ context_enter (fips_api_t api, void *system_context_id unused)
 void
 context_leave (void)
 {
-       context_t *ctx = &current_context;
+       context_t *ctx = current_context;
        timer_query_t *timer, *timer_next;
        monitor_t *monitor, *monitor_next;
 
+       if (ctx == NULL)
+               return;
+
        metrics_collect_available ();
 
        if (ctx->timer_begun_id) {
@@ -84,13 +110,11 @@ context_leave (void)
        ctx->monitor_head = NULL;
        ctx->monitor_tail = NULL;
 
-       current_context.monitors_in_flight = 0;
-
-       metrics_info_fini (&ctx->metrics_info);
+       ctx->monitors_in_flight = 0;
 }
 
 context_t *
 context_get_current (void)
 {
-       return &current_context;
+       return current_context;
 }