sched/idle: Reported an error when an illegal negative value is passed

hulk inclusion
category: bugfix
bugzilla: 180842 https://gitee.com/openeuler/kernel/issues/I4DDEL

Reported an error when an illegal negative value is passed. The allowed value is
0 to INT_MAX.
Signed-off-by: NLi Hua <hucool.lihua@huawei.com>
Reviewed-by: NChen Hui <judy.chenhui@huawei.com>
Signed-off-by: NChen Jun <chenjun102@huawei.com>
Signed-off-by: NZheng Zengkai <zhengzengkai@huawei.com>

include/linux/kernel.h

@@ -556,7 +556,7 @@ extern int sysctl_panic_on_stackoverflow;
 
 extern bool crash_kexec_post_notifiers;
 #ifdef CONFIG_IAS_SMART_IDLE
-extern unsigned long poll_threshold_ns;
+extern int poll_threshold_ns;
 #endif
 
 

kernel/sched/idle.c

@@ -18,7 +18,7 @@ extern char __cpuidle_text_start[], __cpuidle_text_end[];
  * Poll_threshold_ns indicates the maximum polling time before
  * entering real idle.
  */
-unsigned long poll_threshold_ns;
+int poll_threshold_ns;
 #endif
 
 /**
@@ -63,9 +63,9 @@ __setup("hlt", cpu_idle_nopoll_setup);
 #ifdef CONFIG_IAS_SMART_IDLE
 /* looping 2000 times is probably microsecond level for 2GHZ CPU*/
 #define MICRO_LEVEL_COUNT 2000
-static inline void delay_relax(unsigned long delay_max)
+static inline void delay_relax(int delay_max)
 {
-	unsigned long delay_count = 0;
+	int delay_count = 0;
 
 	delay_max = (delay_max < MICRO_LEVEL_COUNT) ? delay_max : MICRO_LEVEL_COUNT;
 	while (unlikely(!tif_need_resched()) && delay_count < delay_max) {
@@ -77,7 +77,7 @@ static inline void delay_relax(unsigned long delay_max)
 
 static inline void smart_idle_poll(void)
 {
-	unsigned long poll_duration = poll_threshold_ns;
+	int poll_duration = poll_threshold_ns;
 	ktime_t cur, stop;
 
 	if (likely(!poll_duration))
@@ -309,7 +309,7 @@ static void do_idle(void)
 {
 	int cpu = smp_processor_id();
 #ifdef CONFIG_IAS_SMART_IDLE
-	unsigned long idle_poll_flag = poll_threshold_ns;
+	int idle_poll_flag = poll_threshold_ns;
 #endif
 	/*
 	 * If the arch has a polling bit, we maintain an invariant:

kernel/sysctl.c

@@ -1655,9 +1655,10 @@ static struct ctl_table ias_table[] = {
 	{
 		.procname	= "smart_idle_threshold",
 		.data		= &poll_threshold_ns,
-		.maxlen		= sizeof(unsigned long),
+		.maxlen		= sizeof(int),
 		.mode		= 0644,
-		.proc_handler	= proc_doulongvec_minmax,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= SYSCTL_ZERO,
 	},
 #endif
 
@@ -1862,7 +1863,6 @@ static struct ctl_table kern_table[] = {
 		.proc_handler	= sysctl_sched_uclamp_handler,
 	},
 #endif
-
 #ifdef CONFIG_SCHED_AUTOGROUP
 	{
 		.procname	= "sched_autogroup_enabled",