Re: [PATCH 2/6] sched: Introduce task_is_running()

From: Peter Zijlstra <peterz@infradead.org>
To: Will Deacon <will@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>,
	Ingo Molnar <mingo@redhat.com>,
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Subject: Re: [PATCH 2/6] sched: Introduce task_is_running()
Date: Wed, 2 Jun 2021 18:46:16 +0200	[thread overview]
Message-ID: <YLe12Ba4CrvhMhFI@hirez.programming.kicks-ass.net> (raw)
In-Reply-To: <20210602145921.GB31179@willie-the-truck>

On Wed, Jun 02, 2021 at 03:59:21PM +0100, Will Deacon wrote:
> On Wed, Jun 02, 2021 at 03:12:27PM +0200, Peter Zijlstra wrote:
> > Replace a bunch of 'p->state == TASK_RUNNING' with a new helper:
> > task_is_running(p).
> > 
> > Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
> > ---
> >  arch/x86/kernel/process.c |    4 ++--
> >  block/blk-mq.c            |    2 +-
> >  include/linux/sched.h     |    2 ++
> >  kernel/locking/lockdep.c  |    2 +-
> >  kernel/rcu/tree_plugin.h  |    2 +-
> >  kernel/sched/core.c       |    6 +++---
> >  kernel/sched/stats.h      |    2 +-
> >  kernel/signal.c           |    2 +-
> >  kernel/softirq.c          |    3 +--
> >  mm/compaction.c           |    2 +-
> >  10 files changed, 14 insertions(+), 13 deletions(-)
> > 
> > --- a/arch/x86/kernel/process.c
> > +++ b/arch/x86/kernel/process.c
> > @@ -931,7 +931,7 @@ unsigned long get_wchan(struct task_stru
> >  	unsigned long start, bottom, top, sp, fp, ip, ret = 0;
> >  	int count = 0;
> >  
> > -	if (p == current || p->state == TASK_RUNNING)
> > +	if (p == current || task_is_running(p))
> 
> Looks like this one in get_wchan() has been cargo-culted across most of
> arch/ so they'll need fixing up before you rename the struct member.

Yeah, this was x86_64 allmodconfig driven, I've already got a bunch of
robot mail telling me other archs need help, I'll fix it iup.

> There's also a weird one in tools/bpf/runqslower/runqslower.bpf.c (!)

I'm tempted to let the bpf people sort their own gunk. This is not an
ABI. I so don't care breaking every script out there.