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Subject[PATCH] cpumask: make cpumask_size() return "unsigned int"
CPUmasks are never big enough to warrant 64-bit code.

Space savings:

add/remove: 0/0 grow/shrink: 1/4 up/down: 3/-17 (-14)
Function old new delta
sched_init_numa 1530 1533 +3
compat_sys_sched_setaffinity 160 159 -1
sys_sched_getaffinity 197 195 -2
sys_sched_setaffinity 183 176 -7
compat_sys_sched_getaffinity 179 172 -7

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
---

include/linux/cpumask.h | 2 +-
kernel/compat.c | 2 +-
kernel/sched/core.c | 2 +-
3 files changed, 3 insertions(+), 3 deletions(-)

--- a/include/linux/cpumask.h
+++ b/include/linux/cpumask.h
@@ -640,7 +640,7 @@ static inline int cpulist_parse(const char *buf, struct cpumask *dstp)
/**
* cpumask_size - size to allocate for a 'struct cpumask' in bytes
*/
-static inline size_t cpumask_size(void)
+static inline unsigned int cpumask_size(void)
{
return BITS_TO_LONGS(nr_cpumask_bits) * sizeof(long);
}
--- a/kernel/compat.c
+++ b/kernel/compat.c
@@ -355,7 +355,7 @@ COMPAT_SYSCALL_DEFINE3(sched_getaffinity, compat_pid_t, pid, unsigned int, len,

ret = sched_getaffinity(pid, mask);
if (ret == 0) {
- size_t retlen = min_t(size_t, len, cpumask_size());
+ unsigned int retlen = min(len, cpumask_size());

if (compat_put_bitmap(user_mask_ptr, cpumask_bits(mask), retlen * 8))
ret = -EFAULT;
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -4799,7 +4799,7 @@ SYSCALL_DEFINE3(sched_getaffinity, pid_t, pid, unsigned int, len,

ret = sched_getaffinity(pid, mask);
if (ret == 0) {
- size_t retlen = min_t(size_t, len, cpumask_size());
+ unsigned int retlen = min(len, cpumask_size());

if (copy_to_user(user_mask_ptr, mask, retlen))
ret = -EFAULT;
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