[PATCH 1/3] mm, vmalloc: Only call setup_vmalloc_vm only in __get_vm_area_node

Zhang Yanfei
2013-06-03T15:31:50Z

Now for insert_vmalloc_vm, it only calls the two functions:
- setup_vmalloc_vm: fill vm_struct and vmap_area instances
- clear_vm_unlist: clear VM_UNLIST bit in vm_struct->flags

So in function __get_vm_area_node, if VM_UNLIST bit unset
in flags, that is the else branch here, we don't need to
clear VM_UNLIST bit for vm->flags since this bit is obviously
not set. That is to say, we could only call setup_vmalloc_vm
instead of insert_vmalloc_vm here. And then we could even
remove the if test here.

Signed-off-by: Zhang Yanfei <zhangyanfei@cn.fujitsu.com>
---
mm/vmalloc.c | 11 +----------
1 files changed, 1 insertions(+), 10 deletions(-)

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index d365724..6580c76 100644
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -1367,16 +1367,7 @@ static struct vm_struct *__get_vm_area_node(unsigned long size,
return NULL;
}

- /*
- * When this function is called from __vmalloc_node_range,
- * we add VM_UNLIST flag to avoid accessing uninitialized
- * members of vm_struct such as pages and nr_pages fields.
- * They will be set later.
- */
- if (flags & VM_UNLIST)
- setup_vmalloc_vm(area, va, flags, caller);
- else
- insert_vmalloc_vm(area, va, flags, caller);
+ setup_vmalloc_vm(area, va, flags, caller);

return area;
}
--
1.7.1