From c930b2c0de32f45ce8f67affe936ce7a05b07b00 Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Fri, 3 Feb 2017 12:22:54 +0100 Subject: [PATCH] sched/core: Convert ___assert_task_state() link time assert to BUILD_BUG_ON() The length of TASK_STATE_TO_CHAR_STR was still checked using the old link-time manual error method - convert it to BUILD_BUG_ON(). This has a couple of advantages: - it's more obvious what's going on - it reduces the size and complexity of - BUILD_BUG_ON() will fail during compilation, with a clearer error message than the link time assert. Acked-by: Linus Torvalds Cc: Mike Galbraith Cc: Peter Zijlstra Cc: Thomas Gleixner Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar --- include/linux/sched.h | 3 --- kernel/sched/core.c | 3 +++ 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/include/linux/sched.h b/include/linux/sched.h index 4a28deb5f210..c204613396cd 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -223,9 +223,6 @@ extern void proc_sched_set_task(struct task_struct *p); #define TASK_STATE_TO_CHAR_STR "RSDTtXZxKWPNn" -extern char ___assert_task_state[1 - 2*!!( - sizeof(TASK_STATE_TO_CHAR_STR)-1 != ilog2(TASK_STATE_MAX)+1)]; - /* Convenience macros for the sake of set_current_state */ #define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE) #define TASK_STOPPED (TASK_WAKEKILL | __TASK_STOPPED) diff --git a/kernel/sched/core.c b/kernel/sched/core.c index bbfb917a9b49..7d76ccb79e91 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -5233,6 +5233,9 @@ void sched_show_task(struct task_struct *p) int ppid; unsigned long state = p->state; + /* 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); + if (!try_get_task_stack(p)) return; if (state) -- 2.39.5