linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Pasha Tatashin <pasha.tatashin@oracle.com>
To: David Miller <davem@davemloft.net>
Cc: mhocko@kernel.org, linux-kernel@vger.kernel.org,
	sparclinux@vger.kernel.org, linux-mm@kvack.org,
	linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org,
	borntraeger@de.ibm.com, heiko.carstens@de.ibm.com
Subject: Re: [v3 0/9] parallelized "struct page" zeroing
Date: Fri, 12 May 2017 13:24:52 -0400	[thread overview]
Message-ID: <6da8d4a6-3332-8331-c329-b05efd88a70d@oracle.com> (raw)
In-Reply-To: <20170512.125708.475573831936972365.davem@davemloft.net>



On 05/12/2017 12:57 PM, David Miller wrote:
> From: Pasha Tatashin <pasha.tatashin@oracle.com>
> Date: Thu, 11 May 2017 16:59:33 -0400
> 
>> We should either keep memset() only for deferred struct pages as what
>> I have in my patches.
>>
>> Another option is to add a new function struct_page_clear() which
>> would default to memset() and to something else on platforms that
>> decide to optimize it.
>>
>> On SPARC it would call STBIs, and we would do one membar call after
>> all "struct pages" are initialized.
> 
> No membars will be performed for single individual page struct clear,
> the cutoff to use the STBI is larger than that.
> 

Right now it is larger, but what I suggested is to add a new optimized 
routine just for this case, which would do STBI for 64-bytes but without 
membar (do membar at the end of memmap_init_zone() and 
deferred_init_memmap()

#define struct_page_clear(page)                                 \
         __asm__ __volatile__(                                   \
         "stxa   %%g0, [%0]%2\n"                                 \
         "stxa   %%xg0, [%0 + %1]%2\n"                           \
         : /* No output */                                       \
         : "r" (page), "r" (0x20), "i"(ASI_BLK_INIT_QUAD_LDD_P))

And insert it into __init_single_page() instead of memset()

The final result is 4.01s/T which is even faster compared to current 4.97s/T



Pasha

  reply	other threads:[~2017-05-12 17:26 UTC|newest]

Thread overview: 46+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-05-05 17:03 [v3 0/9] parallelized "struct page" zeroing Pavel Tatashin
2017-05-05 17:03 ` [v3 1/9] sparc64: simplify vmemmap_populate Pavel Tatashin
2017-05-05 17:03 ` [v3 2/9] mm: defining memblock_virt_alloc_try_nid_raw Pavel Tatashin
2017-05-05 17:03 ` [v3 3/9] mm: add "zero" argument to vmemmap allocators Pavel Tatashin
2017-05-13 19:17   ` kbuild test robot
2017-05-05 17:03 ` [v3 4/9] mm: do not zero vmemmap_buf Pavel Tatashin
2017-05-05 17:03 ` [v3 5/9] mm: zero struct pages during initialization Pavel Tatashin
2017-05-05 17:03 ` [v3 6/9] sparc64: teach sparc not to zero struct pages memory Pavel Tatashin
2017-05-05 17:03 ` [v3 7/9] x86: teach x86 " Pavel Tatashin
2017-05-05 17:03 ` [v3 8/9] powerpc: teach platforms " Pavel Tatashin
2017-05-05 17:03 ` [v3 9/9] s390: " Pavel Tatashin
2017-05-08 11:36   ` Heiko Carstens
2017-05-15 18:24     ` Pasha Tatashin
2017-05-15 23:17       ` Heiko Carstens
2017-05-16  0:33         ` Pasha Tatashin
2017-05-09 18:12 ` [v3 0/9] parallelized "struct page" zeroing Michal Hocko
2017-05-09 18:54   ` Pasha Tatashin
2017-05-10  7:24     ` Michal Hocko
2017-05-10 13:42       ` Pasha Tatashin
2017-05-10 14:57         ` Michal Hocko
2017-05-10 15:01           ` Pasha Tatashin
2017-05-10 15:20             ` David Miller
2017-05-11 20:47             ` Pasha Tatashin
2017-05-11 20:59               ` Pasha Tatashin
2017-05-12 16:57                 ` David Miller
2017-05-12 17:24                   ` Pasha Tatashin [this message]
2017-05-12 17:37                     ` David Miller
2017-05-16 23:50                       ` Benjamin Herrenschmidt
2017-05-12 16:56               ` David Miller
2017-05-10 15:19           ` David Miller
2017-05-10 17:17             ` Matthew Wilcox
2017-05-10 18:00               ` David Miller
2017-05-10 21:11                 ` Matthew Wilcox
2017-05-11  8:05             ` Michal Hocko
2017-05-11 14:35               ` David Miller
2017-05-15 18:12   ` Pasha Tatashin
2017-05-15 19:38     ` Michal Hocko
2017-05-15 20:44       ` Pasha Tatashin
2017-05-16  8:36         ` Michal Hocko
2017-05-26 16:45           ` Pasha Tatashin
2017-05-29 11:53             ` Michal Hocko
2017-05-30 17:16               ` Pasha Tatashin
2017-05-31 16:31                 ` Michal Hocko
2017-05-31 16:51                   ` David Miller
2017-06-01  3:35                   ` Pasha Tatashin
2017-06-01  8:46                     ` Michal Hocko

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=6da8d4a6-3332-8331-c329-b05efd88a70d@oracle.com \
    --to=pasha.tatashin@oracle.com \
    --cc=borntraeger@de.ibm.com \
    --cc=davem@davemloft.net \
    --cc=heiko.carstens@de.ibm.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=linux-s390@vger.kernel.org \
    --cc=linuxppc-dev@lists.ozlabs.org \
    --cc=mhocko@kernel.org \
    --cc=sparclinux@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body. 
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).