From 23d4d31d1f477591d7830712a1e53764e875955f Mon Sep 17 00:00:00 2001
From: Yuxuan Shui <yshuiv7@gmail.com>
Date: Fri, 16 Feb 2024 19:49:28 +0000
Subject: [PATCH] vblank: set SCHED_RR for the SGI_video_sync thread

Signed-off-by: Yuxuan Shui <yshuiv7@gmail.com>
---
 src/picom.c  | 37 -------------------------------------
 src/utils.c  | 37 +++++++++++++++++++++++++++++++++++++
 src/utils.h  |  1 +
 src/vblank.c |  2 ++
 4 files changed, 40 insertions(+), 37 deletions(-)

diff --git a/src/picom.c b/src/picom.c
index a4d3e3e3..6bdfd1d9 100644
--- a/src/picom.c
+++ b/src/picom.c
@@ -19,7 +19,6 @@
 #include <fcntl.h>
 #include <inttypes.h>
 #include <math.h>
-#include <pthread.h>
 #include <sched.h>
 #include <stddef.h>
 #include <stdio.h>
@@ -68,7 +67,6 @@
 #include "file_watch.h"
 #include "list.h"
 #include "options.h"
-#include "rtkit.h"
 #include "statistics.h"
 #include "uthash_extra.h"
 #include "vblank.h"
@@ -2604,41 +2602,6 @@ err:
 	return NULL;
 }
 
-/// Switch to real-time scheduling policy (SCHED_RR) if possible
-///
-/// Make picom realtime to reduce latency, and make rendering times more predictable to
-/// help pacing.
-///
-/// This requires the user to set up permissions for the real-time scheduling. e.g. by
-/// setting `ulimit -r`, or giving us the CAP_SYS_NICE capability.
-void set_rr_scheduling(void) {
-	int priority = sched_get_priority_min(SCHED_RR);
-
-	if (rtkit_make_realtime(0, priority)) {
-		log_info("Set realtime priority to %d with rtkit.", priority);
-		return;
-	}
-
-	// Fallback to use pthread_setschedparam
-	struct sched_param param;
-	int old_policy;
-	int ret = pthread_getschedparam(pthread_self(), &old_policy, &param);
-	if (ret != 0) {
-		log_info("Couldn't get old scheduling priority.");
-		return;
-	}
-
-	param.sched_priority = priority;
-
-	ret = pthread_setschedparam(pthread_self(), SCHED_RR, &param);
-	if (ret != 0) {
-		log_info("Couldn't set real-time scheduling priority to %d.", priority);
-		return;
-	}
-
-	log_info("Set real-time scheduling priority to %d.", priority);
-}
-
 /**
  * Destroy a session.
  *
diff --git a/src/utils.c b/src/utils.c
index 53766d6d..68ec697e 100644
--- a/src/utils.c
+++ b/src/utils.c
@@ -1,8 +1,10 @@
+#include <pthread.h>
 #include <stdio.h>
 #include <string.h>
 #include <sys/uio.h>
 
 #include "compiler.h"
+#include "rtkit.h"
 #include "string_utils.h"
 #include "test.h"
 #include "utils.h"
@@ -272,4 +274,39 @@ void rolling_quantile_pop_front(struct rolling_quantile *rq, int x) {
 	}
 }
 
+/// Switch to real-time scheduling policy (SCHED_RR) if possible
+///
+/// Make picom realtime to reduce latency, and make rendering times more predictable to
+/// help pacing.
+///
+/// This requires the user to set up permissions for the real-time scheduling. e.g. by
+/// setting `ulimit -r`, or giving us the CAP_SYS_NICE capability.
+void set_rr_scheduling(void) {
+	int priority = sched_get_priority_min(SCHED_RR);
+
+	if (rtkit_make_realtime(0, priority)) {
+		log_info("Set realtime priority to %d with rtkit.", priority);
+		return;
+	}
+
+	// Fallback to use pthread_setschedparam
+	struct sched_param param;
+	int old_policy;
+	int ret = pthread_getschedparam(pthread_self(), &old_policy, &param);
+	if (ret != 0) {
+		log_info("Couldn't get old scheduling priority.");
+		return;
+	}
+
+	param.sched_priority = priority;
+
+	ret = pthread_setschedparam(pthread_self(), SCHED_RR, &param);
+	if (ret != 0) {
+		log_info("Couldn't set real-time scheduling priority to %d.", priority);
+		return;
+	}
+
+	log_info("Set real-time scheduling priority to %d.", priority);
+}
+
 // vim: set noet sw=8 ts=8 :
diff --git a/src/utils.h b/src/utils.h
index 22da6c29..962f160f 100644
--- a/src/utils.h
+++ b/src/utils.h
@@ -406,6 +406,7 @@ void rolling_quantile_destroy(struct rolling_quantile *rq);
 int rolling_quantile_estimate(struct rolling_quantile *rq, struct rolling_window *elements);
 void rolling_quantile_push_back(struct rolling_quantile *rq, int x);
 void rolling_quantile_pop_front(struct rolling_quantile *rq, int x);
+void set_rr_scheduling(void);
 
 // Some versions of the Android libc do not have timespec_get(), use
 // clock_gettime() instead.
diff --git a/src/vblank.c b/src/vblank.c
index 81a6cb9e..776d258b 100644
--- a/src/vblank.c
+++ b/src/vblank.c
@@ -183,6 +183,8 @@ static void *sgi_video_sync_thread(void *data) {
 		goto start_failed;
 	}
 
+	log_init_tls();
+	set_rr_scheduling();
 	pthread_mutex_lock(&args->start_mtx);
 	args->start_status = 0;
 	pthread_cond_signal(&args->start_cnd);