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From: losemyheaven@qq.com (=?gb18030?B?wuS62w==?=)
To: kernelnewbies@lists.kernelnewbies.org
Subject: where is __percpu_seg initialized?
Date: Wed, 28 Mar 2018 11:06:55 +0800	[thread overview]
Message-ID: <tencent_C31BFF8CE6F949F85BFCB712D8FD641F4209@qq.com> (raw)
In-Reply-To: <181C899F-91C2-4A27-ACE6-E924B5444234@gmail.com>

setup_per_cpu_areas just prepare a per-cpu area for each
possible cpu, and it doesn't try to start up other possible cpu(s).


The address of  a per-cpu area corresponding to this cpu will be 
written to its per-cpu-area register , before starting up.


Starting up other non-boot cpu happens in start_secondary function.


Larry


------------------ Original ------------------
From:  "Dave Tian"<dave.jing.tian@gmail.com>;
Date:  Sat, Apr 23, 2016 10:02 PM
To:  "??"<losemyheaven@qq.com>;
Cc:  "kernelnewbies"<kernelnewbies@kernelnewbies.org>; 
Subject:  Re: where is __percpu_seg initialized?



load_percpu_segment, which is called by switch_to_new_gdt in setup_per_cpu_areas.

-daveti


> On Apr 23, 2016, at 3:24 AM, ?? <losemyheaven@qq.com> wrote:
> 
> Hi all:
> I knew the kernel implement the per-cpu variable via __percpu_seg. For example on x86 architecture, it's defined as:
> 
> #ifdef CONFIG_X86_64
> #define __percpu_seg		gs
> #define __percpu_mov_op		movq
> #else
> #define __percpu_seg		fs
> #define __percpu_mov_op		movl
> #endif 
>     
> But I'm curious where __percpu_seg is initialized?? I fail to find the relative code. Thanks.
> _______________________________________________
> Kernelnewbies mailing list
> Kernelnewbies at kernelnewbies.org
> http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
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      reply	other threads:[~2018-03-28  3:06 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2016-04-23  7:24 where is __percpu_seg initialized? =?gb18030?B?wuS62w==?=
2016-04-23 14:02 ` Dave Tian
2018-03-28  3:06   ` =?gb18030?B?wuS62w==?= [this message]

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