overlay: Monitor per-ring context switch rate

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

1 files changed, 40 insertions, 3 deletions

diff --git a/overlay/overlay.c b/overlay/overlay.c
index 65137864..3fddde94 100644
--- a/overlay/overlay.c
+++ b/overlay/overlay.c
@@ -102,6 +102,7 @@ struct overlay_gpu_top {
 
 struct overlay_gpu_perf {
 	struct gpu_perf gpu_perf;
+	time_t show_ctx;
 };
 
 struct overlay_gpu_freq {
@@ -127,6 +128,8 @@ struct overlay_context {
 	cairo_t *cr;
 	int width, height;
 
+	time_t time;
+
 	struct overlay_gpu_top gpu_top;
 	struct overlay_gpu_perf gpu_perf;
 	struct overlay_gpu_freq gpu_freq;
@@ -270,6 +273,8 @@ static void init_gpu_perf(struct overlay_context *ctx,
 			  struct overlay_gpu_perf *gp)
 {
 	gpu_perf_init(&gp->gpu_perf, 0);
+
+	gp->show_ctx = 0;
 }
 
 static char *get_comm(pid_t pid, char *comm, int len)
@@ -310,6 +315,16 @@ static void show_gpu_perf(struct overlay_context *ctx, struct overlay_gpu_perf *
 	char buf[1024];
 	cairo_pattern_t *linear;
 	int x, y, y1, y2, n;
+	int has_ctx = 0;
+
+	gpu_perf_update(&gp->gpu_perf);
+
+	for (n = 4; n > 0; n--) {
+		if (gp->gpu_perf.ctx_switch[n-1]) {
+			has_ctx = n;
+			break;
+		}
+	}
 
 	cairo_rectangle(ctx->cr, ctx->width/2+HALF_PAD-.5, PAD-.5, ctx->width/2-SIZE_PAD+1, ctx->height/2-SIZE_PAD+1);
 	cairo_set_source_rgb(ctx->cr, .15, .15, .15);
@@ -326,12 +341,9 @@ static void show_gpu_perf(struct overlay_context *ctx, struct overlay_gpu_perf *
 		return;
 	}
 
-	gpu_perf_update(&gp->gpu_perf);
-
 	y = PAD + 12 - 2;
 	x = ctx->width/2 + HALF_PAD;
 
-
 	for (comm = gp->gpu_perf.comm; comm; comm = comm->next) {
 		int total;
 
@@ -369,6 +381,8 @@ static void show_gpu_perf(struct overlay_context *ctx, struct overlay_gpu_perf *
 		chart_draw(comm->user_data, ctx->cr);
 		y2 += 14;
 	}
+	if (has_ctx || gp->show_ctx)
+		y2 += 14;
 	y1 += -12 - 2;
 	y2 += 14 - 14 + 4;
 
@@ -465,6 +479,27 @@ skip_comm:
 	cairo_move_to(ctx->cr, x, y);
 	cairo_show_text(ctx->cr, buf);
 	y += 14;
+
+	cairo_set_source_rgba(ctx->cr, 1, 1, 1, 1);
+	cairo_move_to(ctx->cr, x, y);
+	if (has_ctx) {
+		int len = sprintf(buf, "Contexts:");
+		for (n = 0; n < has_ctx; n++)
+			len += sprintf(buf + len, "%s %d",
+				       n ? "," : "",
+				       gp->gpu_perf.ctx_switch[n]);
+
+		memset(gp->gpu_perf.ctx_switch, 0, sizeof(gp->gpu_perf.ctx_switch));
+		gp->show_ctx = ctx->time;
+
+		cairo_show_text(ctx->cr, buf);
+		y += 14;
+	} else if (gp->show_ctx) {
+		cairo_show_text(ctx->cr, "Contexts: 0");
+		y += 14;
+		if (ctx->time - gp->show_ctx > 10)
+			gp->show_ctx = 0;
+	}
 }
 
 static void init_gpu_freq(struct overlay_context *ctx,
@@ -841,6 +876,8 @@ int main(int argc, char **argv)
 
 	i = 0;
 	while (1) {
+		ctx.time = time(NULL);
+
 		ctx.cr = cairo_create(ctx.surface);
 		cairo_set_operator(ctx.cr, CAIRO_OPERATOR_CLEAR);
 		cairo_paint(ctx.cr);