Markus reported that kthreads that idle using TASK_IDLE instead of
TASK_INTERRUPTIBLE are reported in as TASK_UNINTERRUPTIBLE and things
like htop mark those red.
This is undesirable, so add an explicit state for TASK_IDLE.
Reported-by: Markus Trippelsdorf <mar...@trippelsdorf.de>
Signed-off-by: Peter Zijlstra (Intel) <pet...@infradead.org>
---
fs/proc/array.c | 21 +++++++++++++--------
include/linux/sched.h | 12 ++++++++++--
include/trace/events/sched.h | 7 ++++---
3 files changed, 27 insertions(+), 13 deletions(-)
--- a/fs/proc/array.c
+++ b/fs/proc/array.c
@@ -118,18 +118,23 @@ static inline void task_name(struct seq_
* simple bit tests.
*/
static const char * const task_state_array[] = {
- "R (running)", /* 0 */
- "S (sleeping)", /* 1 */
- "D (disk sleep)", /* 2 */
- "T (stopped)", /* 4 */
- "t (tracing stop)", /* 8 */
- "X (dead)", /* 16 */
- "Z (zombie)", /* 32 */
+
+ /* states in TASK_REPORT: */
+ "R (running)", /* 0x00 */
+ "S (sleeping)", /* 0x01 */
+ "D (disk sleep)", /* 0x02 */
+ "T (stopped)", /* 0x04 */
+ "t (tracing stop)", /* 0x08 */
+ "X (dead)", /* 0x10 */
+ "Z (zombie)", /* 0x20 */
+
+ /* states beyond TASK_REPORT: */
+ "I (idle)", /* 0x40 */
};
static inline const char *get_task_state(struct task_struct *tsk)
{
- BUILD_BUG_ON(1 + ilog2(TASK_REPORT) != ARRAY_SIZE(task_state_array) -
1);
+ BUILD_BUG_ON(1 + ilog2(TASK_REPORT_MAX) !=
ARRAY_SIZE(task_state_array));
return task_state_array[__get_task_state(tsk)];
}
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1242,22 +1242,30 @@ static inline pid_t task_pgrp_nr(struct
return task_pgrp_nr_ns(tsk, &init_pid_ns);
}
+#define TASK_REPORT_IDLE (TASK_REPORT + 1)
+#define TASK_REPORT_MAX (TASK_REPORT_IDLE << 1)
+
static inline unsigned int __get_task_state(struct task_struct *tsk)
{
unsigned int tsk_state = READ_ONCE(tsk->state);
unsigned int state = (tsk_state | tsk->exit_state) & TASK_REPORT;
+ BUILD_BUG_ON_NOT_POWER_OF_2(TASK_REPORT_MAX);
+
if (tsk_state == TASK_PARKED)
state = TASK_INTERRUPTIBLE;
+ if (tsk_state == TASK_IDLE)
+ state = TASK_REPORT_IDLE;
+
return fls(state);
}
static inline char __task_state_to_char(unsigned int state)
{
- static const char state_char[] = "RSDTtXZ";
+ static const char state_char[] = "RSDTtXZI";
- BUILD_BUG_ON(1 + ilog2(TASK_REPORT) != sizeof(state_char) - 2);
+ BUILD_BUG_ON(1 + ilog2(TASK_REPORT_MAX) != sizeof(state_char) - 1);
return state_char[state];
}
--- a/include/trace/events/sched.h
+++ b/include/trace/events/sched.h
@@ -156,10 +156,11 @@ TRACE_EVENT(sched_switch,
TP_printk("prev_comm=%s prev_pid=%d prev_prio=%d prev_state=%s%s ==>
next_comm=%s next_pid=%d next_prio=%d",
__entry->prev_comm, __entry->prev_pid, __entry->prev_prio,
- (__entry->prev_state & TASK_REPORT) ?
- __print_flags(__entry->prev_state & TASK_REPORT, "|",
+ (__entry->prev_state & (TASK_REPORT_MAX - 1)) ?
+ __print_flags(__entry->prev_state & (TASK_REPORT_MAX - 1),
"|",
{ 0x01, "S" }, { 0x02, "D" }, { 0x04, "T" },
- { 0x08, "t" }, { 0x10, "X" }, { 0x20, "Z" }) :
+ { 0x08, "t" }, { 0x10, "X" }, { 0x20, "Z" },
+ { 0x40, "I" }) :
"R",
__entry->prev_state & TASK_STATE_MAX ? "+" : "",
