linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: Michal Hocko <mhocko@kernel.org>
To: Pavel Tatashin <pasha.tatashin@oracle.com>
Cc: steven.sistare@oracle.com, daniel.m.jordan@oracle.com,
	akpm@linux-foundation.org, linux-kernel@vger.kernel.org,
	tglx@linutronix.de, linux-mm@kvack.org,
	mgorman@techsingularity.net, mingo@kernel.org,
	peterz@infradead.org, rostedt@goodmis.org,
	fengguang.wu@intel.com, dennisszhou@gmail.com
Subject: Re: [PATCH v2] mm: allow deferred page init for vmemmap only
Date: Thu, 10 May 2018 14:30:39 +0200	[thread overview]
Message-ID: <20180510123039.GF5325@dhcp22.suse.cz> (raw)
In-Reply-To: <20180510115356.31164-1-pasha.tatashin@oracle.com>

On Thu 10-05-18 07:53:56, Pavel Tatashin wrote:
[...]
> Here is a sample path, where translation is required, that occurs before
> mm_init():
> 
> start_kernel()
>  trap_init()
>   setup_cpu_entry_areas()
>    setup_cpu_entry_area(cpu)
>     get_cpu_gdt_paddr(cpu)
>      per_cpu_ptr_to_phys(addr)
>       pcpu_addr_to_page(addr)
>        virt_to_page(addr)
>         pfn_to_page(__pa(addr) >> PAGE_SHIFT)

Thanks that helped me to see the problem. On the other hand isn't this a
bit of an overkill? AFAICS this affects only NEED_PER_CPU_KM which is !SMP
and DEFERRED_STRUCT_PAGE_INIT makes only very limited sense on UP,
right?

Or do we have more such places?
-- 
Michal Hocko
SUSE Labs

  reply	other threads:[~2018-05-10 12:30 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-05-10 11:53 [PATCH v2] mm: allow deferred page init for vmemmap only Pavel Tatashin
2018-05-10 12:30 ` Michal Hocko [this message]
2018-05-11 14:17   ` Pavel Tatashin
2018-05-15  9:10     ` Michal Hocko
2018-05-15 12:17       ` Pavel Tatashin
2018-05-15 12:55         ` Michal Hocko
2018-05-15 15:59           ` Pavel Tatashin
2018-05-15 20:38             ` 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=20180510123039.GF5325@dhcp22.suse.cz \
    --to=mhocko@kernel.org \
    --cc=akpm@linux-foundation.org \
    --cc=daniel.m.jordan@oracle.com \
    --cc=dennisszhou@gmail.com \
    --cc=fengguang.wu@intel.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-mm@kvack.org \
    --cc=mgorman@techsingularity.net \
    --cc=mingo@kernel.org \
    --cc=pasha.tatashin@oracle.com \
    --cc=peterz@infradead.org \
    --cc=rostedt@goodmis.org \
    --cc=steven.sistare@oracle.com \
    --cc=tglx@linutronix.de \
    /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).