diff options
| -rw-r--r-- | miscutils/taskset.c | 37 |
1 files changed, 18 insertions, 19 deletions
diff --git a/miscutils/taskset.c b/miscutils/taskset.c index 100b1d926..fb352ab8d 100644 --- a/miscutils/taskset.c +++ b/miscutils/taskset.c @@ -75,27 +75,26 @@ static char *from_cpuset(cpu_set_t *mask) #define TASKSET_PRINTF_MASK "%llx" static unsigned long long from_cpuset(cpu_set_t *mask) { - char *p = (void*)mask; + BUILD_BUG_ON(CPU_SETSIZE < 8*sizeof(int)); - BUILD_BUG_ON(CPU_SETSIZE < sizeof(int)); - - /* Take the least significant bits. Careful! - * Consider both CPU_SETSIZE=4 and CPU_SETSIZE=1024 cases + /* Take the least significant bits. Assume cpu_set_t is + * implemented as an array of unsigned long or unsigned + * int. */ -#if BB_BIG_ENDIAN - /* For big endian, it means LAST bits */ - if (CPU_SETSIZE < sizeof(long)) - p += CPU_SETSIZE - sizeof(int); - else if (CPU_SETSIZE < sizeof(long long)) - p += CPU_SETSIZE - sizeof(long); - else - p += CPU_SETSIZE - sizeof(long long); -#endif - if (CPU_SETSIZE < sizeof(long)) - return *(unsigned*)p; - if (CPU_SETSIZE < sizeof(long long)) - return *(unsigned long*)p; - return *(unsigned long long*)p; + if (CPU_SETSIZE < 8*sizeof(long)) + return *(unsigned*)mask; + if (CPU_SETSIZE < 8*sizeof(long long)) + return *(unsigned long*)mask; +# if BB_BIG_ENDIAN + if (sizeof(long long) > sizeof(long)) { + /* We can put two long in the long long, but they have to + * be swapped: the least significant word comes first in the + * array */ + unsigned long *p = (void*)mask; + return p[0] + ((unsigned long long)p[1] << (8*sizeof(long))); + } +# endif + return *(unsigned long long*)mask; } #endif |