From: Peter Zijlstra Date: Fri, 22 Sep 2017 16:09:26 +0000 (+0200) Subject: sched/debug: Implement consistent task-state printing X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=1593baab910da72480d651ea7bf2ce6e3a25a484;p=openwrt%2Fstaging%2Fblogic.git sched/debug: Implement consistent task-state printing Currently get_task_state() and task_state_to_char() report different states, create a number of common helpers and unify the reported state space. Signed-off-by: Peter Zijlstra (Intel) Cc: Linus Torvalds Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar --- diff --git a/fs/proc/array.c b/fs/proc/array.c index 525157ca25cb..01196d3ad452 100644 --- a/fs/proc/array.c +++ b/fs/proc/array.c @@ -130,19 +130,8 @@ static const char * const task_state_array[] = { static inline const char *get_task_state(struct task_struct *tsk) { - unsigned int state = (tsk->state | tsk->exit_state) & TASK_REPORT; - - /* - * Parked tasks do not run; they sit in __kthread_parkme(). - * Without this check, we would report them as running, which is - * clearly wrong, so we report them as sleeping instead. - */ - if (tsk->state == TASK_PARKED) - state = TASK_INTERRUPTIBLE; - - BUILD_BUG_ON(1 + ilog2(TASK_REPORT) != ARRAY_SIZE(task_state_array)-1); - - return task_state_array[fls(state)]; + BUILD_BUG_ON(1 + ilog2(TASK_REPORT) != ARRAY_SIZE(task_state_array) - 1); + return task_state_array[__get_task_state(tsk)]; } static inline int get_task_umask(struct task_struct *tsk) diff --git a/include/linux/sched.h b/include/linux/sched.h index 92fb8dd5a9e4..163a0b738908 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1243,17 +1243,29 @@ static inline pid_t task_pgrp_nr(struct task_struct *tsk) return task_pgrp_nr_ns(tsk, &init_pid_ns); } -static inline char task_state_to_char(struct task_struct *task) +static inline unsigned int __get_task_state(struct task_struct *tsk) { - const char stat_nam[] = TASK_STATE_TO_CHAR_STR; - unsigned long state = task->state; + unsigned int tsk_state = READ_ONCE(tsk->state); + unsigned int state = (tsk_state | tsk->exit_state) & TASK_REPORT; - state = state ? __ffs(state) + 1 : 0; + if (tsk_state == TASK_PARKED) + state = TASK_INTERRUPTIBLE; - /* Make sure the string lines up properly with the number of task states: */ - BUILD_BUG_ON(sizeof(TASK_STATE_TO_CHAR_STR)-1 != ilog2(TASK_STATE_MAX)+1); + return fls(state); +} + +static inline char __task_state_to_char(unsigned int state) +{ + static const char state_char[] = "RSDTtXZ"; + + BUILD_BUG_ON(1 + ilog2(TASK_REPORT) != sizeof(state_char) - 2); - return state < sizeof(stat_nam) - 1 ? stat_nam[state] : '?'; + return state_char[state]; +} + +static inline char task_state_to_char(struct task_struct *tsk) +{ + return __task_state_to_char(__get_task_state(tsk)); } /**