diff options
| author | Martin Schwidefsky | 2013-12-17 13:41:31 +0100 |
|---|---|---|
| committer | Martin Schwidefsky | 2013-12-18 17:36:38 +0100 |
| commit | 9efe4f2992025c3a4027c60bf36ae9d710ca3781 (patch) | |
| tree | 599ce2a4d390994a52df0edc122495b0db1359c8 /arch/s390 | |
| parent | 61aa4884b70cdf3b2d373e18ebbbada43789eade (diff) | |
s390/mm: optimize randomize_et_dyn for !PF_RANDOMIZE
Skip the call to brk_rnd() if the PF_RANDOMIZE flag is not set for
the process. This avoids the costly get_random_int() call. Modify
arch_randomize_brk() as well to make it look like randomize_et_dyn().
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'arch/s390')
| -rw-r--r-- | arch/s390/kernel/process.c | 14 |
1 files changed, 6 insertions, 8 deletions
diff --git a/arch/s390/kernel/process.c b/arch/s390/kernel/process.c index 7ed0d4e2a435..dd145321d215 100644 --- a/arch/s390/kernel/process.c +++ b/arch/s390/kernel/process.c @@ -261,20 +261,18 @@ static inline unsigned long brk_rnd(void) unsigned long arch_randomize_brk(struct mm_struct *mm) { - unsigned long ret = PAGE_ALIGN(mm->brk + brk_rnd()); + unsigned long ret; - if (ret < mm->brk) - return mm->brk; - return ret; + ret = PAGE_ALIGN(mm->brk + brk_rnd()); + return (ret > mm->brk) ? ret : mm->brk; } unsigned long randomize_et_dyn(unsigned long base) { - unsigned long ret = PAGE_ALIGN(base + brk_rnd()); + unsigned long ret; if (!(current->flags & PF_RANDOMIZE)) return base; - if (ret < base) - return base; - return ret; + ret = PAGE_ALIGN(base + brk_rnd()); + return (ret > base) ? ret : base; } |