diff options
author | Steven Rostedt (VMware) <rostedt@goodmis.org> | 2019-12-19 16:44:53 -0500 |
---|---|---|
committer | Peter Zijlstra <peterz@infradead.org> | 2020-06-25 13:45:44 +0200 |
commit | c3a340f7e7eadac7662ab104ceb16432e5a4c6b2 (patch) | |
tree | 806761b75cc761bc4ef6b48a5228fb384c90598d | |
parent | 590d69796346353878b275c5512c664e3f875f24 (diff) |
sched: Have sched_class_highest define by vmlinux.lds.h
Now that the sched_class descriptors are defined by the linker script, and
this needs to be aware of the existance of stop_sched_class when SMP is
enabled or not, as it is used as the "highest" priority when defined. Move
the declaration of sched_class_highest to the same location in the linker
script that inserts stop_sched_class, and this will also make it easier to
see what should be defined as the highest class, as this linker script
location defines the priorities as well.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20191219214558.682913590@goodmis.org
-rw-r--r-- | include/asm-generic/vmlinux.lds.h | 5 | ||||
-rw-r--r-- | kernel/sched/core.c | 8 | ||||
-rw-r--r-- | kernel/sched/sched.h | 17 |
3 files changed, 21 insertions, 9 deletions
diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index 2186d7b01af6..66fb84c3dc7e 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -114,11 +114,14 @@ * relation to each other. */ #define SCHED_DATA \ + STRUCT_ALIGN(); \ + __begin_sched_classes = .; \ *(__idle_sched_class) \ *(__fair_sched_class) \ *(__rt_sched_class) \ *(__dl_sched_class) \ - *(__stop_sched_class) + *(__stop_sched_class) \ + __end_sched_classes = .; /* * Align to a 32 byte boundary equal to the diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 0208b71bef80..81640fe0eae8 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -6646,6 +6646,14 @@ void __init sched_init(void) unsigned long ptr = 0; int i; + /* Make sure the linker didn't screw up */ + BUG_ON(&idle_sched_class + 1 != &fair_sched_class || + &fair_sched_class + 1 != &rt_sched_class || + &rt_sched_class + 1 != &dl_sched_class); +#ifdef CONFIG_SMP + BUG_ON(&dl_sched_class + 1 != &stop_sched_class); +#endif + wait_bit_init(); #ifdef CONFIG_FAIR_GROUP_SCHED diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index 336887607b3d..4165c06d1d7b 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -1811,7 +1811,7 @@ struct sched_class { #ifdef CONFIG_FAIR_GROUP_SCHED void (*task_change_group)(struct task_struct *p, int type); #endif -}; +} __aligned(32); /* STRUCT_ALIGN(), vmlinux.lds.h */ static inline void put_prev_task(struct rq *rq, struct task_struct *prev) { @@ -1825,17 +1825,18 @@ static inline void set_next_task(struct rq *rq, struct task_struct *next) next->sched_class->set_next_task(rq, next, false); } -#ifdef CONFIG_SMP -#define sched_class_highest (&stop_sched_class) -#else -#define sched_class_highest (&dl_sched_class) -#endif +/* Defined in include/asm-generic/vmlinux.lds.h */ +extern struct sched_class __begin_sched_classes[]; +extern struct sched_class __end_sched_classes[]; + +#define sched_class_highest (__end_sched_classes - 1) +#define sched_class_lowest (__begin_sched_classes - 1) #define for_class_range(class, _from, _to) \ - for (class = (_from); class != (_to); class = class->next) + for (class = (_from); class != (_to); class--) #define for_each_class(class) \ - for_class_range(class, sched_class_highest, NULL) + for_class_range(class, sched_class_highest, sched_class_lowest) extern const struct sched_class stop_sched_class; extern const struct sched_class dl_sched_class; |