From: Michal Hocko <[email protected]> Now that all the callers handle vm_brk failure we can change it wait for mmap_sem killable to help oom_reaper to not get blocked just because vm_brk gets blocked behind mmap_sem readers.
Cc: "Kirill A. Shutemov" <[email protected]> Cc: Oleg Nesterov <[email protected]> Cc: Andrea Arcangeli <[email protected]> Signed-off-by: Michal Hocko <[email protected]> --- include/linux/mm.h | 2 +- mm/mmap.c | 9 +++------ 2 files changed, 4 insertions(+), 7 deletions(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index 4ee6a3561540..dccaea8682f2 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -2077,7 +2077,7 @@ static inline void mm_populate(unsigned long addr, unsigned long len) {} #endif /* These take the mm semaphore themselves */ -extern unsigned long vm_brk(unsigned long, unsigned long); +extern unsigned long __must_check vm_brk(unsigned long, unsigned long); extern int vm_munmap(unsigned long, size_t); extern unsigned long __must_check vm_mmap(struct file *, unsigned long, unsigned long, unsigned long, diff --git a/mm/mmap.c b/mm/mmap.c index 5d33c841e3a2..3f264fb14118 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -2718,12 +2718,9 @@ unsigned long vm_brk(unsigned long addr, unsigned long len) unsigned long ret; bool populate; - /* - * XXX not all users are chcecking the return value, convert - * to down_write_killable after they are able to cope with - * error - */ - down_write(&mm->mmap_sem); + if (down_write_killable(&mm->mmap_sem)) + return -EINTR; + ret = do_brk(addr, len); populate = ((mm->def_flags & VM_LOCKED) != 0); up_write(&mm->mmap_sem); -- 2.7.0
