Merge "hung task: check specific tasks for long uninterruptible sleep state" (d0c491f1) · Commits · e / devices / android_kernel_fairphone_FP3

fs/proc/base.c

+54 −0

Original line number	Diff line number	Diff line
		@@ -2896,6 +2896,52 @@ static int proc_tgid_io_accounting(struct seq_file m, struct pid_namespace ns,
		}
		#endif /* CONFIG_TASK_IO_ACCOUNTING */

		#ifdef CONFIG_DETECT_HUNG_TASK
		static ssize_t proc_hung_task_detection_enabled_read(struct file *file,
		char __user buf, size_t count, loff_t ppos)
		{
		struct task_struct *task = get_proc_task(file_inode(file));
		char buffer[PROC_NUMBUF];
		size_t len;
		bool hang_detection_enabled;

		if (!task)
		return -ESRCH;
		hang_detection_enabled = task->hang_detection_enabled;
		put_task_struct(task);

		len = snprintf(buffer, sizeof(buffer), "%d\n", hang_detection_enabled);

		return simple_read_from_buffer(buf, sizeof(buffer), ppos, buffer, len);
		}

		static ssize_t proc_hung_task_detection_enabled_write(struct file *file,
		const char __user buf, size_t count, loff_t ppos)
		{
		struct task_struct *task;
		bool hang_detection_enabled;
		int rv;

		rv = kstrtobool_from_user(buf, count, &hang_detection_enabled);
		if (rv < 0)
		return rv;

		task = get_proc_task(file_inode(file));
		if (!task)
		return -ESRCH;
		task->hang_detection_enabled = hang_detection_enabled;
		put_task_struct(task);

		return count;
		}

		static const struct file_operations proc_hung_task_detection_enabled_operations = {
		.read = proc_hung_task_detection_enabled_read,
		.write = proc_hung_task_detection_enabled_write,
		.llseek = generic_file_llseek,
		};
		#endif

		#ifdef CONFIG_USER_NS
		static int proc_id_map_open(struct inode inode, struct file file,
		const struct seq_operations *seq_ops)
		@@ -3138,6 +3184,10 @@ static const struct pid_entry tgid_base_stuff[] = {
		#ifdef CONFIG_HARDWALL
		ONE("hardwall", S_IRUGO, proc_pid_hardwall),
		#endif
		#ifdef CONFIG_DETECT_HUNG_TASK
		REG("hang_detection_enabled", 0666,
		proc_hung_task_detection_enabled_operations),
		#endif
		#ifdef CONFIG_USER_NS
		REG("uid_map", S_IRUGO\|S_IWUSR, proc_uid_map_operations),
		REG("gid_map", S_IRUGO\|S_IWUSR, proc_gid_map_operations),
		@@ -3526,6 +3576,10 @@ static const struct pid_entry tid_base_stuff[] = {
		#ifdef CONFIG_HARDWALL
		ONE("hardwall", S_IRUGO, proc_pid_hardwall),
		#endif
		#ifdef CONFIG_DETECT_HUNG_TASK
		REG("hang_detection_enabled", 0666,
		proc_hung_task_detection_enabled_operations),
		#endif
		#ifdef CONFIG_USER_NS
		REG("uid_map", S_IRUGO\|S_IWUSR, proc_uid_map_operations),
		REG("gid_map", S_IRUGO\|S_IWUSR, proc_gid_map_operations),

include/linux/sched.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -1946,6 +1946,7 @@ struct task_struct {
		#ifdef CONFIG_DETECT_HUNG_TASK
		/* hung task detection */
		unsigned long last_switch_count;
		bool hang_detection_enabled;
		#endif
		/* filesystem information */
		struct fs_struct *fs;

include/linux/sched/sysctl.h

+1 −0

Original line number	Diff line number	Diff line
		@@ -6,6 +6,7 @@ extern int sysctl_hung_task_check_count;
		extern unsigned int sysctl_hung_task_panic;
		extern unsigned long sysctl_hung_task_timeout_secs;
		extern int sysctl_hung_task_warnings;
		extern int sysctl_hung_task_selective_monitoring;
		extern int proc_dohung_task_timeout_secs(struct ctl_table *table, int write,
		void __user *buffer,
		size_t lenp, loff_t ppos);

kernel/hung_task.c

+13 −1

Original line number	Diff line number	Diff line
		@@ -17,12 +17,21 @@
		#include <linux/sysctl.h>
		#include <linux/utsname.h>
		#include <trace/events/sched.h>
		#include <linux/sched/sysctl.h>

		/*
		* The number of tasks checked:
		*/
		int __read_mostly sysctl_hung_task_check_count = PID_MAX_LIMIT;

		/*
		* Selective monitoring of hung tasks.
		*
		* if set to 1, khungtaskd skips monitoring tasks, which has
		* task_struct->hang_detection_enabled value not set, else monitors all tasks.
		*/
		int sysctl_hung_task_selective_monitoring = 1;

		/*
		* Limit number of tasks checked in a batch.
		*
		@@ -179,6 +188,9 @@ static void check_hung_uninterruptible_tasks(unsigned long timeout)
		}
		/* use "==" to skip the TASK_KILLABLE tasks waiting on NFS */
		if (t->state == TASK_UNINTERRUPTIBLE)
		/* Check for selective monitoring */
		if (!sysctl_hung_task_selective_monitoring \|\|
		t->hang_detection_enabled)
		check_hung_task(t, timeout);
		}
		unlock:

kernel/sysctl.c

+10 −0

Original line number	Diff line number	Diff line
		@@ -1186,6 +1186,16 @@ static struct ctl_table kern_table[] = {
		.proc_handler = proc_dointvec_minmax,
		.extra1 = &neg_one,
		},
		{
		.procname = "hung_task_selective_monitoring",
		.data = &sysctl_hung_task_selective_monitoring,
		.maxlen = sizeof(int),
		.mode = 0644,
		.proc_handler = proc_dointvec_minmax,
		.extra1 = &zero,
		.extra2 = &one,
		},

		#endif
		#ifdef CONFIG_RT_MUTEXES
		{