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

On 9/22/18 8:29 PM, Nathan Chancellor wrote:

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 <redacted>
---

v1 -> v2:

Fix reported build error by using DECLARE instead of DEFINE

Thanks for update !!
Acked-by: Santosh shilimkar <redacted>