diff options
Diffstat (limited to 'include/linux/sched.h')
| -rw-r--r-- | include/linux/sched.h | 36 |
1 files changed, 27 insertions, 9 deletions
diff --git a/include/linux/sched.h b/include/linux/sched.h index bb343136ddd0..d380bffee2ef 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -1001,7 +1001,7 @@ struct task_struct { #ifdef CONFIG_ARCH_HAS_CPU_PASID unsigned pasid_activated:1; #endif -#ifdef CONFIG_CPU_SUP_INTEL +#ifdef CONFIG_X86_BUS_LOCK_DETECT unsigned reported_split_lock:1; #endif #ifdef CONFIG_TASK_DELAY_ACCT @@ -1121,9 +1121,12 @@ struct task_struct { /* * executable name, excluding path. * - * - normally initialized setup_new_exec() - * - access it with [gs]et_task_comm() - * - lock it with task_lock() + * - normally initialized begin_new_exec() + * - set it with set_task_comm() + * - strscpy_pad() to ensure it is always NUL-terminated and + * zero-padded + * - task_lock() to ensure the operation is atomic and the name is + * fully updated. */ char comm[TASK_COMM_LEN]; @@ -1441,6 +1444,7 @@ struct task_struct { /* Timestamp for last schedule: */ unsigned long long ftrace_timestamp; + unsigned long long ftrace_sleeptime; /* * Number of functions that haven't been traced @@ -1898,7 +1902,7 @@ extern unsigned long init_stack[THREAD_SIZE / sizeof(unsigned long)]; #ifdef CONFIG_THREAD_INFO_IN_TASK # define task_thread_info(task) (&(task)->thread_info) -#elif !defined(__HAVE_THREAD_FUNCTIONS) +#else # define task_thread_info(task) ((struct thread_info *)(task)->stack) #endif @@ -1938,10 +1942,23 @@ static inline void set_task_comm(struct task_struct *tsk, const char *from) __set_task_comm(tsk, from, false); } -extern char *__get_task_comm(char *to, size_t len, struct task_struct *tsk); +/* + * - Why not use task_lock()? + * User space can randomly change their names anyway, so locking for readers + * doesn't make sense. For writers, locking is probably necessary, as a race + * condition could lead to long-term mixed results. + * The strscpy_pad() in __set_task_comm() can ensure that the task comm is + * always NUL-terminated and zero-padded. Therefore the race condition between + * reader and writer is not an issue. + * + * - BUILD_BUG_ON() can help prevent the buf from being truncated. + * Since the callers don't perform any return value checks, this safeguard is + * necessary. + */ #define get_task_comm(buf, tsk) ({ \ - BUILD_BUG_ON(sizeof(buf) != TASK_COMM_LEN); \ - __get_task_comm(buf, sizeof(buf), tsk); \ + BUILD_BUG_ON(sizeof(buf) < TASK_COMM_LEN); \ + strscpy_pad(buf, (tsk)->comm); \ + buf; \ }) #ifdef CONFIG_SMP @@ -2002,7 +2019,8 @@ static inline void set_tsk_need_resched(struct task_struct *tsk) static inline void clear_tsk_need_resched(struct task_struct *tsk) { - clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED); + atomic_long_andnot(_TIF_NEED_RESCHED | _TIF_NEED_RESCHED_LAZY, + (atomic_long_t *)&task_thread_info(tsk)->flags); } static inline int test_tsk_need_resched(struct task_struct *tsk) |