[PATCH v2] RDS: IB: Use DECLARE_PER_CPU_SHARED_ALIGNED for rds_ib_stats

[Nathan Chancellor]

Clang warns when two declarations' section attributes don't match.

net/rds/ib_stats.c:40:1: warning: section does not match previous
declaration [-Wsection]
DEFINE_PER_CPU_SHARED_ALIGNED(struct rds_ib_statistics, rds_ib_stats);
^
./include/linux/percpu-defs.h:142:2: note: expanded from macro
'DEFINE_PER_CPU_SHARED_ALIGNED'
        DEFINE_PER_CPU_SECTION(type, name,
PER_CPU_SHARED_ALIGNED_SECTION) \
        ^
./include/linux/percpu-defs.h:93:9: note: expanded from macro
'DEFINE_PER_CPU_SECTION'
        extern __PCPU_ATTRS(sec) __typeof__(type) name;
\
               ^
./include/linux/percpu-defs.h:49:26: note: expanded from macro
'__PCPU_ATTRS'
        __percpu __attribute__((section(PER_CPU_BASE_SECTION sec)))
\
                                ^
net/rds/ib.h:446:1: note: previous attribute is here
DECLARE_PER_CPU(struct rds_ib_statistics, rds_ib_stats);
^
./include/linux/percpu-defs.h:111:2: note: expanded from macro
'DECLARE_PER_CPU'
        DECLARE_PER_CPU_SECTION(type, name, "")
        ^
./include/linux/percpu-defs.h:87:9: note: expanded from macro
'DECLARE_PER_CPU_SECTION'
        extern __PCPU_ATTRS(sec) __typeof__(type) name
               ^
./include/linux/percpu-defs.h:49:26: note: expanded from macro
'__PCPU_ATTRS'
        __percpu __attribute__((section(PER_CPU_BASE_SECTION sec)))
\
                                ^
1 warning generated.

The initial definition was added in commit ec16227e1414 ("RDS/IB:
Infiniband transport") and the cache aligned definition was added in
commit e6babe4cc4ce ("RDS/IB: Stats and sysctls") right after. The
definition probably should have been updated in net/rds/ib.h, which is
what this patch does.

Link: https://github.com/ClangBuiltLinux/linux/issues/114
Signed-off-by: Nathan Chancellor <natechancellor@xxxxxxxxx>
---

v1 -> v2:

Fix reported build error by using DECLARE instead of DEFINE

 net/rds/ib.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/rds/ib.h b/net/rds/ib.h
index 73427ff439f9..71ff356ee702 100644
--- a/net/rds/ib.h
+++ b/net/rds/ib.h
@@ -443,7 +443,7 @@ int rds_ib_send_grab_credits(struct rds_ib_connection *ic, u32 wanted,
 int rds_ib_xmit_atomic(struct rds_connection *conn, struct rm_atomic_op *op);
 
 /* ib_stats.c */
-DECLARE_PER_CPU(struct rds_ib_statistics, rds_ib_stats);
+DECLARE_PER_CPU_SHARED_ALIGNED(struct rds_ib_statistics, rds_ib_stats);
 #define rds_ib_stats_inc(member) rds_stats_inc_which(rds_ib_stats, member)
 #define rds_ib_stats_add(member, count) \
 		rds_stats_add_which(rds_ib_stats, member, count)
-- 
2.19.0