Subject: linux-next: build failure after merge of the rcu tree

From: Stephen Rothwell <[email-masked]>
Date: Thu, 28 May 2020 19:05:01 +1000

Hi all,

After merging the rcu tree, today's linux-next build (powercp
allyesconfig) failed like this:

ld: kernel/rcu/refperf.o:(.discard+0x0): multiple definition of `__pcpu_unique_srcu_ctl_perf_srcu_data'; kernel/rcu/rcuperf.o:(.discard+0x0): first defined here

Caused by commit

  786a25497743 ("refperf: Add a test to measure performance of read-side synchronization")

From srcutree.h:

 * Note that although DEFINE_STATIC_SRCU() hides the name from other
 * files, the per-CPU variable rules nevertheless require that the
 * chosen name be globally unique.

I have applied the following patch for today.

From: Stephen Rothwell <[email-masked]>
Date: Thu, 28 May 2020 18:57:17 +1000
Subject: [PATCH] refperf: uniqify name

Signed-off-by: Stephen Rothwell <[email-masked]>
---
 kernel/rcu/refperf.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/kernel/rcu/refperf.c b/kernel/rcu/refperf.c
index 8c4a63257be9..47df72c492b3 100644
--- a/kernel/rcu/refperf.c
+++ b/kernel/rcu/refperf.c
@@ -133,8 +133,8 @@ static struct ref_perf_ops rcu_ops = {

 // Definitions for SRCU ref perf testing.
-DEFINE_STATIC_SRCU(srcu_ctl_perf);
-static struct srcu_struct *srcu_ctlp = &srcu_ctl_perf;
+DEFINE_STATIC_SRCU(ref_srcu_ctl_perf);
+static struct srcu_struct *srcu_ctlp = &ref_srcu_ctl_perf;
 
 static void srcu_ref_perf_read_section(int nloops)
 {
-- 
2.26.2

-- 
Cheers,
Stephen Rothwell