Dear Alexandre,


在 2021/3/24 17:29, Alexandre Belloni 写道:

On 24/03/2021 05:09:39-0400, He Ying wrote:

quoted

We found these warnings in arch/powerpc/kernel/time.c as follows:
warning: symbol 'decrementer_max' was not declared. Should it be static?
warning: symbol 'rtc_lock' was not declared. Should it be static?
warning: symbol 'dtl_consumer' was not declared. Should it be static?

Declare 'decrementer_max' in powerpc asm/time.h.
Include linux/mc146818rtc.h in powerpc kernel/time.c where 'rtc_lock'
is declared. And remove duplicated declaration of 'rtc_lock' in powerpc
platforms/chrp/time.c because it has included linux/mc146818rtc.h.
Move 'dtl_consumer' definition behind "include <asm/dtl.h>" because it
is declared there.

Reported-by: Hulk Robot <redacted>
Signed-off-by: He Ying <redacted>
---
V2:
- Instead of including linux/mc146818rtc.h in powerpc kernel/time.c, declare
   rtc_lock in powerpc asm/time.h.
V3:
- Recover to V1, that is including linux/mc146818rtc.h in powerpc
   kernel/time.c. And remove duplicated declaration of 'rtc_lock' in powerpc
   platforms/chrp/time.c because it has included linux/mc146818rtc.h.

  arch/powerpc/include/asm/time.h    | 1 +
  arch/powerpc/kernel/time.c         | 9 ++++-----
  arch/powerpc/platforms/chrp/time.c | 2 --
  3 files changed, 5 insertions(+), 7 deletions(-)

diff --git a/arch/powerpc/include/asm/time.h b/arch/powerpc/include/asm/time.h
index 8dd3cdb25338..2cd2b50bedda 100644
--- a/arch/powerpc/include/asm/time.h
+++ b/arch/powerpc/include/asm/time.h

@@ -22,6 +22,7 @@ extern unsigned long tb_ticks_per_jiffy;
  extern unsigned long tb_ticks_per_usec;
  extern unsigned long tb_ticks_per_sec;
  extern struct clock_event_device decrementer_clockevent;
+extern u64 decrementer_max;
  
  
  extern void generic_calibrate_decr(void);

diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c
index b67d93a609a2..ac81f043bf49 100644
--- a/arch/powerpc/kernel/time.c
+++ b/arch/powerpc/kernel/time.c

@@ -55,8 +55,9 @@
  #include <linux/sched/cputime.h>
  #include <linux/sched/clock.h>
  #include <linux/processor.h>
-#include <asm/trace.h>
+#include <linux/mc146818rtc.h>

I'm fine with that but I really think my suggestion to make the rtc_lock
local to the platforms was better because it is only used to synchronize
between concurrent invocations of chrp_set_rtc_time or
maple_set_rtc_time. The rtc core will never do that and the only case
would be concurrent calls to rtc_ops.set_time and
update_persistent_clock64 (which should also be removed at some point).

Many thanks for your suggestion. As you suggest, rtc_lock should be 
local to platforms.

Does it mean not only powerpc but also all other platforms should adapt 
this change?

It might be a big change. I have no idea if that's OK. What are other 
maintainers' opinions?


Thanks.