mm: make vm_brk killable

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.

Signed-off-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Michal Hocko 2016-05-23 16:25:42 -07:00 committed by Linus Torvalds
parent ecc2bc8ac0
commit 2d6c928241
2 changed files with 4 additions and 7 deletions

View File

@ -2011,7 +2011,7 @@ 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,

View File

@ -2712,12 +2712,9 @@ 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);