[PATCH] sched: fix an unused function "node_cpu" warning

[PATCH] sched: fix an unused function "node_cpu" warning

[Qian Cai]

Clang reports a warning,

kernel/locking/osq_lock.c:25:19: warning: unused function 'node_cpu'
[-Wunused-function]

due to osq_lock() calls vcpu_is_preempted(node_cpu(node->prev))), but
vcpu_is_preempted() is compiled away. Fix it by converting the dummy
vcpu_is_preempted() from a macro to a proper static inline function.

Signed-off-by: Qian Cai <cai@lca.pw>
---
 include/linux/sched.h | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/include/linux/sched.h b/include/linux/sched.h
index f0edee94834a..e2e91960d79f 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1856,7 +1856,10 @@ static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
  * running or not.
  */
 #ifndef vcpu_is_preempted
-# define vcpu_is_preempted(cpu)	false
+static inline bool vcpu_is_preempted(int cpu)
+{
+	return false;
+}
 #endif
 
 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);
-- 
1.8.3.1

Re: [PATCH] sched: fix an unused function "node_cpu" warning

[Mel Gorman]

On Tue, Sep 17, 2019 at 10:34:54AM -0400, Qian Cai wrote:
> Clang reports a warning,
> 
> kernel/locking/osq_lock.c:25:19: warning: unused function 'node_cpu'
> [-Wunused-function]
> 
> due to osq_lock() calls vcpu_is_preempted(node_cpu(node->prev))), but
> vcpu_is_preempted() is compiled away. Fix it by converting the dummy
> vcpu_is_preempted() from a macro to a proper static inline function.
> 
> Signed-off-by: Qian Cai <cai@lca.pw>

Acked-by: Mel Gorman <mgorman@suse.de>

-- 
Mel Gorman
SUSE Labs

[tip: sched/urgent] sched/core: Convert vcpu_is_preempted() from macro to an inline function

[tip-bot2 for Qian Cai]

The following commit has been merged into the sched/urgent branch of tip:

Commit-ID:     42fd8baab31f53bed2952485fcf0e92f244c5e55
Gitweb:        https://git.kernel.org/tip/42fd8baab31f53bed2952485fcf0e92f244c5e55
Author:        Qian Cai <cai@lca.pw>
AuthorDate:    Tue, 17 Sep 2019 10:34:54 -04:00
Committer:     Ingo Molnar <mingo@kernel.org>
CommitterDate: Wed, 18 Sep 2019 12:38:17 +02:00

sched/core: Convert vcpu_is_preempted() from macro to an inline function

Clang reports this warning:

  kernel/locking/osq_lock.c:25:19: warning: unused function 'node_cpu' [-Wunused-function]

due to osq_lock() calling vcpu_is_preempted(node_cpu(node->prev))), but
vcpu_is_preempted() is compiled away. Fix it by converting the dummy
vcpu_is_preempted() from a macro to a proper static inline function.

Signed-off-by: Qian Cai <cai@lca.pw>
Acked-by: Mel Gorman <mgorman@suse.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bsegall@google.com
Cc: dietmar.eggemann@arm.com
Cc: juri.lelli@redhat.com
Cc: rostedt@goodmis.org
Cc: vincent.guittot@linaro.org
Link: https://lkml.kernel.org/r/1568730894-10483-1-git-send-email-cai@lca.pw
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
 include/linux/sched.h | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/include/linux/sched.h b/include/linux/sched.h
index f0edee9..e2e9196 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -1856,7 +1856,10 @@ static inline void set_task_cpu(struct task_struct *p, unsigned int cpu)
  * running or not.
  */
 #ifndef vcpu_is_preempted
-# define vcpu_is_preempted(cpu)	false
+static inline bool vcpu_is_preempted(int cpu)
+{
+	return false;
+}
 #endif
 
 extern long sched_setaffinity(pid_t pid, const struct cpumask *new_mask);