[tracker/SCHED_IDLE: 1/2] libtracker-common: Added functionality for SCHED_IDLE scheduler priority

[Martyn James Russell <mr src gnome org>]

commit 98a7c47a61f79c85893e356096db44a0207eded0
Author: Martyn Russell <martyn lanedo com>
Date:   Fri Sep 23 10:20:51 2011 +0100

    libtracker-common: Added functionality for SCHED_IDLE scheduler priority
    
    Also added calls the tracker-miner-fs and tracker-extract

 src/libtracker-common/Makefile.am      |    2 +
 src/libtracker-common/tracker-common.h |    1 +
 src/libtracker-common/tracker-sched.c  |   77 ++++++++++++++++++++++++++++++++
 src/libtracker-common/tracker-sched.h  |   33 ++++++++++++++
 src/miners/fs/tracker-main.c           |   16 +++---
 src/tracker-extract/tracker-main.c     |   14 +++---
 6 files changed, 128 insertions(+), 15 deletions(-)
---
diff --git a/src/libtracker-common/Makefile.am b/src/libtracker-common/Makefile.am
index 5bcd345..406ca38 100644
--- a/src/libtracker-common/Makefile.am
+++ b/src/libtracker-common/Makefile.am
@@ -25,6 +25,7 @@ libtracker_common_la_SOURCES = \
 	tracker-ioprio.c \
 	tracker-keyfile-object.c \
 	tracker-log.c \
+	tracker-sched.c \
 	tracker-type-utils.c \
 	tracker-utils.c \
 	tracker-crc32.c \
@@ -43,6 +44,7 @@ noinst_HEADERS = \
 	tracker-file-utils.h \
 	tracker-keyfile-object.h \
 	tracker-ontologies.h \
+	tracker-sched.h \
 	tracker-type-utils.h \
 	tracker-utils.h \
 	tracker-crc32.h \
diff --git a/src/libtracker-common/tracker-common.h b/src/libtracker-common/tracker-common.h
index 1263efc..e5616b0 100644
--- a/src/libtracker-common/tracker-common.h
+++ b/src/libtracker-common/tracker-common.h
@@ -38,6 +38,7 @@
 #include "tracker-log.h"
 #include "tracker-ontologies.h"
 #include "tracker-os-dependant.h"
+#include "tracker-sched.h"
 #include "tracker-type-utils.h"
 #include "tracker-utils.h"
 #include "tracker-locale.h"
diff --git a/src/libtracker-common/tracker-sched.c b/src/libtracker-common/tracker-sched.c
new file mode 100644
index 0000000..acec7a3
--- /dev/null
+++ b/src/libtracker-common/tracker-sched.c
@@ -0,0 +1,77 @@
+/*
+ * Copyright (C) 2011, Nokia <ivan frade nokia com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ * Boston, MA  02110-1301, USA.
+ */
+
+#include "config.h"
+
+#ifdef __linux__
+
+#ifndef _GNU_SOURCE
+#define _GNU_SOURCE
+#endif
+
+#include <errno.h>
+#include <sched.h>
+
+#include <glib.h>
+
+#include "tracker-sched.h"
+
+gboolean
+tracker_sched_idle (void)
+{
+	struct sched_param sp;
+
+	/* Set process scheduling parameters:
+	 * This is used so we don't steal scheduling priority from
+	 * the most important applications - like the phone
+	 * application which has a real time requirement here. This
+	 * is detailed in Nokia bug #95573
+	 */
+	g_message ("Setting scheduler policy to SCHED_IDLE");
+
+	if (sched_getparam (0, &sp) == 0) {
+		if (sched_setscheduler (0, SCHED_IDLE, &sp) != 0) {
+			const gchar *str = g_strerror (errno);
+
+			g_warning ("Could not set scheduler policy, %s",
+			           str ? str : "no error given");
+
+			return FALSE;
+		}
+	} else {
+		const gchar *str = g_strerror (errno);
+
+		g_warning ("Could not get scheduler policy, %s",
+		           str ? str : "no error given");
+
+		return FALSE;
+	}
+
+	return TRUE;
+}
+
+#else /* __linux__ */
+
+gboolean
+tracker_sched_idle (gboolean enable)
+{
+	return TRUE;
+}
+
+#endif /* __linux__ */
diff --git a/src/libtracker-common/tracker-sched.h b/src/libtracker-common/tracker-sched.h
new file mode 100644
index 0000000..a9d8fe7
--- /dev/null
+++ b/src/libtracker-common/tracker-sched.h
@@ -0,0 +1,33 @@
+/*
+ * Copyright (C) 2011, Nokia <ivan frade nokia com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ * Boston, MA  02110-1301, USA.
+ */
+
+#ifndef __LIBTRACKER_COMMON_SCHED_H__
+#define __LIBTRACKER_COMMON_SCHED_H__
+
+G_BEGIN_DECLS
+
+#if !defined (__LIBTRACKER_COMMON_INSIDE__) && !defined (TRACKER_COMPILATION)
+#error "only <libtracker-common/tracker-common.h> must be included directly."
+#endif
+
+gboolean tracker_sched_idle (void);
+
+G_END_DECLS
+
+#endif /* __LIBTRACKER_COMMON_SCHED_H__ */
diff --git a/src/miners/fs/tracker-main.c b/src/miners/fs/tracker-main.c
index 251bf8a..775584e 100644
--- a/src/miners/fs/tracker-main.c
+++ b/src/miners/fs/tracker-main.c
@@ -26,10 +26,6 @@
 #include <errno.h>
 #include <sys/types.h>
 #include <unistd.h>
-#if defined(__linux__)
-#include <linux/sched.h>
-#endif
-#include <sched.h>
 
 #include <glib.h>
 #include <glib-object.h>
@@ -39,6 +35,7 @@
 #include <libtracker-common/tracker-log.h>
 #include <libtracker-common/tracker-ontologies.h>
 #include <libtracker-common/tracker-file-utils.h>
+#include <libtracker-common/tracker-sched.h>
 
 #include <libtracker-miner/tracker-miner.h>
 
@@ -172,8 +169,11 @@ initialize_signal_handler (void)
 }
 
 static void
-initialize_priority (void)
+initialize_priority_and_scheduling (void)
 {
+	/* Set CPU priority */
+	tracker_sched_idle ();
+
 	/* Set disk IO priority and scheduling */
 	tracker_ioprio_init ();
 
@@ -714,9 +714,6 @@ main (gint argc, gchar *argv[])
 
 	initialize_signal_handler ();
 
-	/* This makes sure we don't steal all the system's resources */
-	initialize_priority ();
-
 	/* Initialize logging */
 	config = tracker_config_new ();
 
@@ -735,6 +732,9 @@ main (gint argc, gchar *argv[])
 
 	sanity_check_option_values (config);
 
+	/* This makes sure we don't steal all the system's resources */
+	initialize_priority_and_scheduling ();
+
 	main_loop = g_main_loop_new (NULL, FALSE);
 
 	g_message ("Checking if we're running as a daemon:");
diff --git a/src/tracker-extract/tracker-main.c b/src/tracker-extract/tracker-main.c
index e115975..dc94675 100644
--- a/src/tracker-extract/tracker-main.c
+++ b/src/tracker-extract/tracker-main.c
@@ -28,10 +28,6 @@
 #include <errno.h>
 #include <sys/types.h>
 #include <unistd.h>
-#if defined(__linux__)
-#include <linux/sched.h>
-#endif
-#include <sched.h>
 
 #include <glib.h>
 #include <glib-object.h>
@@ -47,6 +43,7 @@
 #include <libtracker-common/tracker-os-dependant.h>
 #include <libtracker-common/tracker-ioprio.h>
 #include <libtracker-common/tracker-locale.h>
+#include <libtracker-common/tracker-sched.h>
 
 #include "tracker-albumart.h"
 #include "tracker-config.h"
@@ -118,8 +115,11 @@ static GOptionEntry entries[] = {
 };
 
 static void
-initialize_priority (void)
+initialize_priority_and_scheduling (void)
 {
+	/* Set CPU priority */
+	tracker_sched_idle ();
+
 	/* Set disk IO priority and scheduling */
 	tracker_ioprio_init ();
 
@@ -273,7 +273,7 @@ run_standalone (void)
 	tracker_albumart_init ();
 
 	/* This makes sure we don't steal all the system's resources */
-	initialize_priority ();
+	initialize_priority_and_scheduling ();
 
 	file = g_file_new_for_commandline_arg (filename);
 	uri = g_file_get_uri (file);
@@ -398,7 +398,7 @@ main (int argc, char *argv[])
 	sanity_check_option_values (config);
 
 	/* This makes sure we don't steal all the system's resources */
-	initialize_priority ();
+	initialize_priority_and_scheduling ();
 	tracker_memory_setrlimits ();
 
 	if (disable_shutdown) {