From mboxrd@z Thu Jan 1 00:00:00 1970 From: Oleg Nesterov Subject: Re: [PATCH, RESEND] getrusage: fill ru_maxrss value Date: Tue, 16 Dec 2008 16:20:54 +0100 Message-ID: <20081216152054.GA17012@redhat.com> References: <20081216155641.1411f8a7@psychotron.englab.brq.redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <20081216155641.1411f8a7-YzwxZg+R7evSU73v1vjTzyO4YDw3rz4rAInAS/Ez/D0@public.gmane.org> Sender: linux-api-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Jiri Pirko Cc: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Andrew Morton , Michael Kerrisk , linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Hugh Dickins , jlim-sJ/iWh9BUns@public.gmane.org, kosaki.motohiro-+CUm20s59erQFUHtdCDX3A@public.gmane.org List-Id: linux-api@vger.kernel.org On 12/16, Jiri Pirko wrote: > > This patch makes ->ru_maxrss value in struct rusage filled accordingly to > rss hiwater mark. This struct is filled as a parameter to > getrusage syscall. ->ru_maxrss value is set to pages which might be correct > as "time" application converts it to KBs. > > To make this happen we extend struct signal_struct by two fields. The > first one is ->maxrss which we use to store rss hiwater of the task. The > second one is ->cmaxrss which we use to store highest rss hiwater of all > task childs. These values are used in k_getrusage() to actually fill > ->ru_maxrss. k_getrusage() uses current rss hiwater value directly > if mm struct exists. > > We clear the ->maxrss as a part of flush_old_exec() to be consistent > because bprm_mm_init() does not copy ->hiwater_rss. Imho the patch is fine, but > @@ -1598,6 +1601,15 @@ static void k_getrusage(struct task_struct *p, int who, struct rusage *r) > out: > cputime_to_timeval(utime, &r->ru_utime); > cputime_to_timeval(stime, &r->ru_stime); > + > + task_lock(p); > + if (p->mm) { > + unsigned long maxrss = get_mm_hiwater_rss(p->mm); > + > + if (r->ru_maxrss < maxrss) > + r->ru_maxrss = maxrss; > + } > + task_unlock(p); I think the code above should check "if (who != RUSAGE_CHILDREN) ? Oleg. -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html