Re: [PATCH 06/18] libmultipath: use shared_ptr for checker classes

On Tue, 2026-05-12 at 20:49 -0400, Benjamin Marzinski wrote:
> On Tue, May 05, 2026 at 05:43:20PM +0200, Martin Wilck wrote:
> > Utilize the share_ptr code for tracking the refcount of checker
> > classes.
> > 
> > Signed-off-by: Martin Wilck <[email protected]>
> > ---
> >  libmultipath/checkers.c | 98 +++++++++----------------------------
> > ----
> >  libmultipath/checkers.h |  2 -
> >  2 files changed, 20 insertions(+), 80 deletions(-)
> > 
> > diff --git a/libmultipath/checkers.c b/libmultipath/checkers.c
> > index 8f18ca6..a3b9cc8 100644
> > --- a/libmultipath/checkers.c
> > +++ b/libmultipath/checkers.c
> [...]
> > @@ -163,8 +143,7 @@ static struct checker_class
> > *add_checker_class(const char *name)
> >  		goto out;
> >  
> >  	c->mp_init = (int (*)(struct checker *)) dlsym(c->handle,
> > "libcheck_mp_init");
> > -	c->reset = (void (*)(void)) dlsym(c->handle,
> > "libcheck_reset");
> > -	c->thread = (void *(*)(void*)) dlsym(c->handle,
> > "libcheck_thread");
> > +	c->reset = (void (*)(void))dlsym(c->handle,
> > "libcheck_reset");
> 
> Nitpick. Dropped a space here.

I didn't do that. clang-format did, as it also reformats context lines
in patches. I think clang-format is correct. We usually don't use space
after cast, do we? (As usual, our code base is inconsistent in this
respect).

While I don't want to enforce formatting style throughout the entire
code base, I tend to keep the changes that clang-format applies to
context lines (be it only to avoid red lights from the GitHub CI).

Do you disagree with this policy?

Regards
Martin

> 
> >  	c->pending = (int (*)(struct checker *)) dlsym(c->handle,
> > "libcheck_pending");
> >  	c->need_wait = (bool (*)(struct checker *)) dlsym(c-
> > >handle, "libcheck_need_wait");
> >  	/* These 5 functions can be NULL. call dlerror() to clear
> > out any
> [...]
> > @@ -371,43 +350,6 @@ bad_id:
> >  	return generic_msg[CHECKER_MSGID_NONE];
> >  }
> 
> Removing the checker thread stuff is more of a cleanup from d1ebd977.
> It
> should probably either be it's own cleanup patch, or it should at
> least
> get mentioned in the commit message.
>   
> > -static void checker_cleanup_thread(void *arg)
> > -{
> > -	struct checker_class *cls = arg;
> > -
> > -	free_checker_class(cls);
> > -	rcu_unregister_thread();
> > -}
> > -
> > -static void *checker_thread_entry(void *arg)
> > -{
> > -	struct checker_context *ctx = arg;
> > -	void *rv;
> > -
> > -	rcu_register_thread();
> > -	pthread_cleanup_push(checker_cleanup_thread, ctx->cls);
> > -	rv = ctx->cls->thread(ctx);
> > -	pthread_cleanup_pop(1);
> > -	return rv;
> > -}
> > -
> 
> Also, start_checker_thread() is stil declared in
> libmultipath/checkers.h,
> along with a comment.
> 
> -Ben
> 
> > -int start_checker_thread(pthread_t *thread, const pthread_attr_t
> > *attr,
> > -			 struct checker_context *ctx)
> > -{
> > -	int rv;
> > -
> > -	assert(ctx && ctx->cls && ctx->cls->thread);
> > -	/* Take a ref here, lest the class be freed before the
> > thread starts */
> > -	(void)checker_class_ref(ctx->cls);
> > -	rv = pthread_create(thread, attr, checker_thread_entry,
> > ctx);
> > -	if (rv != 0) {
> > -		condlog(1, "failed to start checker thread for %s:
> > %m",
> > -			ctx->cls->name);
> > -		checker_class_unref(ctx->cls);
> > -	}
> > -	return rv;
> > -}
> > -
> >  void checker_clear_message (struct checker *c)
> >  {
> >  	if (!c)