Re: [PATCH v2 17/17] arch, x86: pmem api for ensuring durability of persistent memory updates

[Williams, Dan J]

On Tue, 2015-06-30 at 13:21 +0300, Dan Carpenter wrote:
> On Thu, Jun 25, 2015 at 05:37:49AM -0400, Dan Williams wrote:
> > diff --git a/include/linux/compiler.h b/include/linux/compiler.h
> > index 867722591be2..9a528d945498 100644
> > --- a/include/linux/compiler.h
> > +++ b/include/linux/compiler.h
> > @@ -21,6 +21,7 @@
> >  # define __rcu		__attribute__((noderef, address_space(4)))
> 
> On this side of the #ifdef CONFIG_SPARSE_RCU_POINTER statement then
> __pmem isn't defined so it leads to a build error running a CHECKER on
> today's linux-next.
> 
> I would define __pmem away, but I don't understand why __pmem and
> CONFIG_SPARSE_RCU_POINTER are related at all.  Maybe it should be
> outside the if statement?
> 

Yes it should be outside the if...

8<----
Subject: sparse: fix misplaced __pmem definition

From: Dan Williams <dan.j.williams@xxxxxxxxx>

Move the definition of __pmem outside of CONFIG_SPARSE_RCU_POINTER to fix:

drivers/nvdimm/pmem.c:198:17: sparse: too many arguments for function __builtin_expect
drivers/nvdimm/pmem.c:36:33: sparse: expected ; at end of declaration
drivers/nvdimm/pmem.c:48:21: sparse: void declaration

...due to __pmem failing to be defined in some configurations when
CONFIG_SPARSE_RCU_POINTER=y.

Reported-by: kbuild test robot <fengguang.wu@xxxxxxxxx>
Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx>
---
 include/linux/compiler.h |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/include/linux/compiler.h b/include/linux/compiler.h
index 26fc8bc77f85..d8fbd500330e 100644
--- a/include/linux/compiler.h
+++ b/include/linux/compiler.h
@@ -17,11 +17,11 @@
 # define __release(x)	__context__(x,-1)
 # define __cond_lock(x,c)	((c) ? ({ __acquire(x); 1; }) : 0)
 # define __percpu	__attribute__((noderef, address_space(3)))
+# define __pmem		__attribute__((noderef, address_space(5)))
 #ifdef CONFIG_SPARSE_RCU_POINTER
 # define __rcu		__attribute__((noderef, address_space(4)))
 #else
 # define __rcu
-# define __pmem		__attribute__((noderef, address_space(5)))
 #endif
 extern void __chk_user_ptr(const volatile void __user *);
 extern void __chk_io_ptr(const volatile void __iomem *);