Re: [PATCH 1/2] hung_task: Show the blocker task if the task is hung on mutex

[Google]

On Wed, 19 Feb 2025 18:58:10 -0500
Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:

> On Thu, 20 Feb 2025 08:09:08 +0900
> Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx> wrote:
> 
> > So something like this?
> > 
> > unsigned int	block_flags;
> > union {
> > 	struct mutex	*mutex;
> > 	struct rwsem	+rwsem;
> > 	struct rtmutex	*rtmutex;
> > } blocked_on;
> > 
> > enum {
> > 	BLOCKED_ON_MUTEX;
> > 	BLOCKED_ON_RWSEM;
> > 	BLOCKED_ON_RTMUTEX;
> > 	BLOCKED_ON_IO;
> > } block_reason;
> > 
> > For the safety, we may anyway lock the task anyway, but that is the
> > same as stacktrace.
> 
> Why not make it into a single entity?
> 
> struct blocked_on {
> 	unsigned int	flags;
> 	union {
> 		struct mutex	*mutex;
> 		struct rwsem	*rwsem;
> 		struct rtmutex	*rtmutex;
> 	} blocked_on;
> };

Yes, and we also merge current mutex_waiter too.

Thank you,

> 
> -- Steve
> 


-- 
Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>