linux-kernel - Re: [PATCH] hugetlb: /proc/meminfo shows data for all sizes of hugepages

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20110307201314.GA5354@mgebm.net>
Date:	Mon, 7 Mar 2011 15:13:14 -0500
From:	Eric B Munson <emunson@...bm.net>
To:	Dave Hansen <dave@...ux.vnet.ibm.com>
Cc:	Petr Holasek <pholasek@...hat.com>, linux-kernel@...r.kernel.org,
	anton@...hat.com, Andi Kleen <ak@...ux.intel.com>,
	Naoya Horiguchi <n-horiguchi@...jp.nec.com>,
	Mel Gorman <mel@....ul.ie>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Wu Fengguang <fengguang.wu@...el.com>, linux-mm@...ck.org
Subject: Re: [PATCH] hugetlb: /proc/meminfo shows data for all sizes of
 hugepages

On Mon, 07 Mar 2011, Dave Hansen wrote:

> On Mon, 2011-03-07 at 14:05 +0100, Petr Holasek wrote:
> > +       for_each_hstate(h)
> > +               seq_printf(m,
> > +                               "HugePages_Total:   %5lu\n"
> > +                               "HugePages_Free:    %5lu\n"
> > +                               "HugePages_Rsvd:    %5lu\n"
> > +                               "HugePages_Surp:    %5lu\n"
> > +                               "Hugepagesize:   %8lu kB\n",
> > +                               h->nr_huge_pages,
> > +                               h->free_huge_pages,
> > +                               h->resv_huge_pages,
> > +                               h->surplus_huge_pages,
> > +                               1UL << (huge_page_order(h) + PAGE_SHIFT - 10));
> >  }
> 
> It sounds like now we'll get a meminfo that looks like:
> 
> ...
> AnonHugePages:    491520 kB
> HugePages_Total:       5
> HugePages_Free:        2
> HugePages_Rsvd:        3
> HugePages_Surp:        1
> Hugepagesize:       2048 kB
> HugePages_Total:       2
> HugePages_Free:        1
> HugePages_Rsvd:        1
> HugePages_Surp:        1
> Hugepagesize:    1048576 kB
> DirectMap4k:       12160 kB
> DirectMap2M:     2082816 kB
> DirectMap1G:     2097152 kB
> 
> At best, that's a bit confusing.  There aren't any other entries in
> meminfo that occur more than once.  Plus, this information is available
> in the sysfs interface.  Why isn't that sufficient?
> 
> Could we do something where we keep the default hpage_size looking like
> it does now, but append the size explicitly for the new entries?
> 
> HugePages_Total(1G):       2
> HugePages_Free(1G):        1
> HugePages_Rsvd(1G):        1
> HugePages_Surp(1G):        1
> 
> -- Dave

I second that, this will help minimize the change to userspace tools that currently read
meminfo for huge page information.

Eric

Download attachment "signature.asc" of type "application/pgp-signature" (491 bytes)