openkylin
/
linux
mirror of https://gitee.com/openkylin/linux.git
9
0
Fork 0
Code Issues Projects Releases Wiki Activity

powerpc/mm: Add a bunch of (un)likely annotations to do_page_fault 

Mostly for the failure cases

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Benjamin Herrenschmidt 2017-07-19 14:49:41 +10:00 committed by Michael Ellerman
parent 11ccdd33d6
commit b15021d994
1 changed files with 10 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

20
arch/powerpc/mm/fault.c
View File

@ -400,7 +400,7 @@ static int __do_page_fault(struct pt_regs *regs, unsigned long address,
* source. If this is invalid we can skip the address space check,
* thus avoiding the deadlock.
*/
if (!down_read_trylock(&mm->mmap_sem)) {
if (unlikely(!down_read_trylock(&mm->mmap_sem))) {
if (!is_user && !search_exception_tables(regs->nip))
return bad_area_nosemaphore(regs, address);
@ -416,11 +416,11 @@ static int __do_page_fault(struct pt_regs *regs, unsigned long address,
}
vma = find_vma(mm, address);
if (!vma)
if (unlikely(!vma))
return bad_area(regs, address);
if (vma->vm_start <= address)
if (likely(vma->vm_start <= address))
goto good_area;
if (!(vma->vm_flags & VM_GROWSDOWN))
if (unlikely(!(vma->vm_flags & VM_GROWSDOWN)))
return bad_area(regs, address);
/*
@ -453,7 +453,7 @@ static int __do_page_fault(struct pt_regs *regs, unsigned long address,
if (address + 2048 < uregs->gpr[1] && !store_update_sp)
return bad_area(regs, address);
}
if (expand_stack(vma, address))
if (unlikely(expand_stack(vma, address)))
return bad_area(regs, address);
good_area:
@ -468,18 +468,18 @@ static int __do_page_fault(struct pt_regs *regs, unsigned long address,
* below wouldn't be valid on those processors. This -may-
* break programs compiled with a really old ABI though.
*/
if (!(vma->vm_flags & VM_EXEC) &&
(cpu_has_feature(CPU_FTR_NOEXECUTE) ||
!(vma->vm_flags & (VM_READ | VM_WRITE))))
if (unlikely(!(vma->vm_flags & VM_EXEC) &&
(cpu_has_feature(CPU_FTR_NOEXECUTE) ||
!(vma->vm_flags & (VM_READ | VM_WRITE)))))
return bad_area(regs, address);
/* a write */
} else if (is_write) {
if (!(vma->vm_flags & VM_WRITE))
if (unlikely(!(vma->vm_flags & VM_WRITE)))
return bad_area(regs, address);
flags |= FAULT_FLAG_WRITE;
/* a read */
} else {
if (!(vma->vm_flags & (VM_READ | VM_EXEC | VM_WRITE)))
if (unlikely(!(vma->vm_flags & (VM_READ | VM_EXEC | VM_WRITE))))
return bad_area(regs, address);
}