Merge "msm: mdss: handle race condition in pingpong done counter" (9444b5e5) · Commits · e / devices / android_kernel_xiaomi_markw

drivers/video/msm/mdss/mdss_mdp_intf_cmd.c

+9 −1

Original line number	Diff line number	Diff line
		@@ -1019,6 +1019,7 @@ static void mdss_mdp_cmd_pingpong_done(void *arg)
		struct mdss_mdp_cmd_ctx *ctx = ctl->intf_ctx[MASTER_CTX];
		struct mdss_mdp_vsync_handler *tmp;
		ktime_t vsync_time;
		bool sync_ppdone;

		if (!ctx) {
		pr_err("%s: invalid ctx\n", __func__);
		@@ -1044,11 +1045,18 @@ static void mdss_mdp_cmd_pingpong_done(void *arg)

		MDSS_XLOG(ctl->num, atomic_read(&ctx->koff_cnt), ctx->current_pp_num);

		/*
		* check state of sync ctx before decrementing koff_cnt to avoid race
		* condition. That is, once both koff_cnt have been served and new koff
		* can be triggered (sctx->koff_cnt could change)
		*/
		sync_ppdone = mdss_mdp_cmd_do_notifier(ctx);

		if (atomic_add_unless(&ctx->koff_cnt, -1, 0)) {
		if (atomic_read(&ctx->koff_cnt))
		pr_err("%s: too many kickoffs=%d!\n", __func__,
		atomic_read(&ctx->koff_cnt));
		if (mdss_mdp_cmd_do_notifier(ctx)) {
		if (sync_ppdone) {
		atomic_inc(&ctx->pp_done_cnt);
		schedule_work(&ctx->pp_done_work);