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

From: "Paul E. McKenney" <[email-masked]>
Date: Tue, 18 Aug 2020 07:08:24 -0700

On Tue, Aug 18, 2020 at 11:43:54AM +1000, Stephen Rothwell wrote:
> Hi all,
> 
> After merging the rcu tree, today's linux-next build (x86_64 allmodconfig)
> failed like this:
> 
> In file included from include/linux/kernel.h:15,
>                  from kernel/rcu/rcuscale.c:13:
> kernel/rcu/rcuscale.c: In function 'rcu_scale_writer':
> kernel/rcu/rcuscale.c:430:6: error: 'perf_type' undeclared (first use in this function); did you mean 'kernfs_type'?
>   430 |      perf_type, PERF_FLAG, me, MIN_MEAS);
>       |      ^~~~~~~~~
> include/linux/printk.h:319:35: note: in definition of macro 'pr_alert'
>   319 |  printk(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
>       |                                   ^~~~~~~~~~~
> kernel/rcu/rcuscale.c:430:6: note: each undeclared identifier is reported only once for each function it appears in
>   430 |      perf_type, PERF_FLAG, me, MIN_MEAS);
>       |      ^~~~~~~~~
> include/linux/printk.h:319:35: note: in definition of macro 'pr_alert'
>   319 |  printk(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
>       |                                   ^~~~~~~~~~~
> kernel/rcu/rcuscale.c:430:17: error: 'PERF_FLAG' undeclared (first use in this function)
>   430 |      perf_type, PERF_FLAG, me, MIN_MEAS);
>       |                 ^~~~~~~~~
> include/linux/printk.h:319:35: note: in definition of macro 'pr_alert'
>   319 |  printk(KERN_ALERT pr_fmt(fmt), ##__VA_ARGS__)
>       |                                   ^~~~~~~~~~~
> kernel/rcu/rcuscale.c:431:27: error: 'n_rcu_perf_writer_finished' undeclared (first use in this function); did you mean 'n_rcu_scale_writer_finished'?
>   431 |    if (atomic_inc_return(&n_rcu_perf_writer_finished) >=
>       |                           ^~~~~~~~~~~~~~~~~~~~~~~~~~
>       |                           n_rcu_scale_writer_finished
> 
> Caused by commit
> 
>   a20b5bd09813 ("rcuperf: Change rcuperf to rcuscale")
> 
> I have used the rcu tree from next-20200817 for today.

My test scripts clearly are not dealing gracefully with filename changes,
are they?  :-/

Thank you for catching this one!  I have queued a fix.

							Thanx, Paul