[LTP] [PATCH] getcpu01: Reinstate node_id test

Cyril Hrubis chrubis@suse.cz
Mon Dec 12 16:53:25 CET 2022


Hi!
> Presently the node_id is only checked on i386 and it is broken. The
> sched_getcpu call was substituted for getcpu when
> available. sched_getcpu does not have the node_id parameter and does
> not even call SYS_getcpu if it can be completed by vDSO.
> 
> Also we can at least check the node_id on x86_64 as well.

I suppose that the getcpu manual page is a bit confusing, the function
is implemented on most of the major achitectures and as VDSO on most of
them too. It was only added first to x86 architectures.

> Signed-off-by: Richard Palethorpe <rpalethorpe@suse.com>
> ---
>  testcases/kernel/syscalls/getcpu/getcpu01.c | 22 +++++++++------------
>  1 file changed, 9 insertions(+), 13 deletions(-)
> 
> diff --git a/testcases/kernel/syscalls/getcpu/getcpu01.c b/testcases/kernel/syscalls/getcpu/getcpu01.c
> index fcc273e29..21c67f412 100644
> --- a/testcases/kernel/syscalls/getcpu/getcpu01.c
> +++ b/testcases/kernel/syscalls/getcpu/getcpu01.c
> @@ -15,20 +15,16 @@
>  #include <stdio.h>
>  #include <stdlib.h>
>  #include <sys/types.h>
> +#include "tst_test.h"
>  #include "lapi/syscalls.h"
>  #include "lapi/cpuset.h"
> -#include "tst_test.h"
>  #include "config.h"
>  
>  static inline int get_cpu(unsigned *cpu_id,
> -			  unsigned *node_id LTP_ATTRIBUTE_UNUSED,
> -			  void *cache_struct LTP_ATTRIBUTE_UNUSED)
> +			  unsigned *node_id)
>  {
> -#ifndef HAVE_SCHED_GETCPU
> -	return tst_syscall(__NR_getcpu, cpu_id, node_id, cache_struct);
> -#else
> -	*cpu_id = sched_getcpu();
> -#endif
> +	return tst_syscall(__NR_getcpu, cpu_id, node_id, NULL);

The call is mostly implemneted as VDSO so it would make much more sense
to test the libc function instead and test the implementation that is
actually used in production.

>  	return 0;
>  }
>  
> @@ -78,7 +74,7 @@ realloc:
>  	return cpu_max;
>  }
>  
> -#ifdef __i386__
> +#if  defined(__i386__) || defined(__x86_64__)
>  static unsigned int get_nodeid(unsigned int cpu_id)
>  {
>  	DIR *directory_parent, *directory_node;
> @@ -125,22 +121,22 @@ static void run(void)
>  {
>  	unsigned int cpu_id, node_id = 0;
>  	unsigned int cpu_set;


The get_nodeid() just parses sysfs, that should be portable, can't we
just get rid of the ifdefs completely instead?

> -#ifdef __i386__
> +#if defined(__i386__) || defined(__x86_64__)
>  	unsigned int node_set;
>  #endif
>  
>  	cpu_set = set_cpu_affinity();
> -#ifdef __i386__
> +#if defined(__i386__) || defined(__x86_64__)
>  	node_set = get_nodeid(cpu_set);
>  #endif
>  
> -	TEST(get_cpu(&cpu_id, &node_id, NULL));
> +	TEST(get_cpu(&cpu_id, &node_id));
>  	if (TST_RET == 0) {
>  		if (cpu_id != cpu_set)
>  			tst_res(TFAIL, "getcpu() returned wrong value"
>  				" expected cpuid:%d, returned value cpuid: %d",
>  				cpu_set, cpu_id);
> -#ifdef __i386__
> +#if defined(__i386__) || defined(__x86_64__)
>  		else if (node_id != node_set)
>  			tst_res(TFAIL, "getcpu() returned wrong value"
>  				" expected  node id:%d returned  node id:%d",
> -- 
> 2.38.1
> 
> 
> -- 
> Mailing list info: https://lists.linux.it/listinfo/ltp

-- 
Cyril Hrubis
chrubis@suse.cz


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