On a modern Linux distro, compiling the following program fails: #include<stdlib.h> #include<stdint.h> #include<pthread.h> #include<linux/sched/types.h>

void main() { struct sched_attr sa;

return; }

with: /usr/include/linux/sched/types.h:8:8: \ error: redefinition of ‘struct sched_param’ 8 | struct sched_param { | ^~~~~~~~~~~ In file included from /usr/include/x86_64-linux-gnu/bits/sched.h:74, from /usr/include/sched.h:43, from /usr/include/pthread.h:23, from /tmp/s.c:4: /usr/include/x86_64-linux-gnu/bits/types/struct_sched_param.h:23:8: note: originally defined here 23 | struct sched_param | ^~~~~~~~~~~

This is also causing a problem with using sched_attr in Chrome. The issue is struct sched_param is already provided by glibc and is in POSIX.

Guard the kernel's UAPI definition of sched_param with __KERNEL__ so that userspace and the kernel can both compile.

Signed-off-by: Joel Fernandes (Google) joel@joelfernandes.org --- v1->v2: With the chance that libc needs resolving something, I'm resending with libc-alpha added as suggested by Christian, and minor commit message fixes.

include/uapi/linux/sched/types.h | 2 ++ 1 file changed, 2 insertions(+)

diff --git a/include/uapi/linux/sched/types.h b/include/uapi/linux/sched/types.h index c852153ddb0d3..1f10d935a63fe 100644 --- a/include/uapi/linux/sched/types.h +++ b/include/uapi/linux/sched/types.h @@ -4,9 +4,11 @@

#include <linux/types.h>

+#if defined(__KERNEL__) struct sched_param { int sched_priority; }; +#endif

#define SCHED_ATTR_SIZE_VER0 48 /* sizeof first published struct */ #define SCHED_ATTR_SIZE_VER1 56 /* add: util_{min,max} */