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 Signed-off-by: Peter Zijlstra (Intel) --- 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 ? "+" : "",