On Mon, Apr 28, 2014 at 07:21:27PM +0200, Richard Weinberger wrote:
> Am 28.04.2014 19:17, schrieb Randy Dunlap:
> >
> > uml defconfig on x86_64:
> >
> > CC arch/um/kernel/asm-offsets.s
> > In file included from include/linux/sem.h:5:0,
> > from include/linux/sched.h:35,
> > from arch/x86/um/shared/sysdep/kernel-offsets.h:2,
> > from arch/um/kernel/asm-offsets.c:1:
> > include/linux/rcupdate.h:257:20: error: static declaration of
> > 'rcu_sysrq_start' follows non-static declaration
> > include/linux/rcupdate.h:250:6: note: previous declaration of
> > 'rcu_sysrq_start' was here
> > include/linux/rcupdate.h:260:20: error: static declaration of
> > 'rcu_sysrq_end' follows non-static declaration
> > include/linux/rcupdate.h:251:6: note: previous declaration of
> > 'rcu_sysrq_end' was here
> > make[2]: *** [arch/um/kernel/asm-offsets.s] Error 1
> >
> >
> > Please test your patch(es).
Against exactly what? ;-)
> Just in case, to build an x86_64 UML please run:
>
> make defconfig ARCH=um SUBARCH=x86_64
> make linux ARCH=um SUBARCH=x86_64
Hmmm.... Builds without errors in my local tree.
Make a clone of linux-next...
OK, now I get a different build failure:
/home/paulmck/public_git/linux-next/drivers/tty/sysrq.c:514: undefined
reference to `rcu_sysrq_start'
/home/paulmck/public_git/linux-next/drivers/tty/sysrq.c:558: undefined
reference to `rcu_sysrq_end'
This is due to Rik's "#include <linux/rcupdate.h>" getting lost somehow.
This #include is needed in drivers/tty/sysrq.c.
But maybe I need to be using some other branch of linux-next. Am currently
on 5bd4e10b96ce20271688aa31d8bd739441249152, which is origin/master. And
is also next-20140428. If I should be somewhere else, please let me know.
OK, it also appears that my change to make TINY_RCU work is also missing,
possibly because Randy applied it by hand.
Please see below for a patch against next-20140428 that makes this build
for me. This is derived from Rik's patch, my patch, and is consistent with
Arnd's patch.
Thanx, Paul
------------------------------------------------------------------------
diff --git a/drivers/tty/sysrq.c b/drivers/tty/sysrq.c
index 6c3d11b..38d5f9a 100644
--- a/drivers/tty/sysrq.c
+++ b/drivers/tty/sysrq.c
@@ -46,6 +46,7 @@
#include <linux/jiffies.h>
#include <linux/syscalls.h>
#include <linux/of.h>
+#include <linux/rcupdate.h>
#include <asm/ptrace.h>
#include <asm/irq_regs.h>
diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h
index e9cc71c..7b0a669 100644
--- a/include/linux/rcupdate.h
+++ b/include/linux/rcupdate.h
@@ -247,8 +247,17 @@ void rcu_idle_enter(void);
void rcu_idle_exit(void);
void rcu_irq_enter(void);
void rcu_irq_exit(void);
+#ifdef CONFIG_RCU_STALL_COMMON
void rcu_sysrq_start(void);
void rcu_sysrq_end(void);
+#else /* #ifdef CONFIG_RCU_STALL_COMMON */
+static inline void rcu_sysrq_start(void)
+{
+}
+static inline void rcu_sysrq_end(void)
+{
+}
+#endif /* #else #ifdef CONFIG_RCU_STALL_COMMON */
#ifdef CONFIG_RCU_USER_QS
void rcu_user_enter(void);
diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c
index 20caaf0..a2aeb4d 100644
--- a/kernel/rcu/update.c
+++ b/kernel/rcu/update.c
@@ -322,7 +322,8 @@ int rcu_jiffies_till_stall_check(void)
void rcu_sysrq_start(void)
{
- rcu_cpu_stall_suppress = 2;
+ if (!rcu_cpu_stall_suppress)
+ rcu_cpu_stall_suppress = 2;
}
void rcu_sysrq_end(void)
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
