Date: Mon, 14 Feb 2005 15:57:06 +0200 From: Andrey Simonenko <simon@comsys.ntu-kpi.kiev.ua> To: Ashwin Chandra <ashcs@ucla.edu> Cc: freebsd-hackers@freebsd.org Subject: Re: Kernel Monitor? Message-ID: <20050214135706.GA581@pm514-9.comsys.ntu-kpi.kiev.ua> In-Reply-To: <000c01c5126f$354f81c0$58e243a4@ash> References: <000c01c5126f$354f81c0$58e243a4@ash>
next in thread | previous in thread | raw e-mail | index | archive | help
> FOREACH_PROC_IN_SYSTEM(p) {
> mtx_lock(&Giant);
> PROC_LOCK(p);
> printf("%d %d\n", (int)p->p_stats->p_ru.ru_isrss, (int)p->p_stats->p_ru.ru_idrss);
> PROC_UNLOCK(p);
> mtx_unlock(&Giant);
> }
This code is incorrect, because you should get sx_slock(&allproc_lock)
before FOREACH_PROC_IN_SYSTEM and release sx_sunlock(&allproc_lock)
after this loop. If you don't do this, then p in some iteration
will point to nothing. Locking Giant, as I understand, here is not
required (even vefore FOREACH_...).
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20050214135706.GA581>