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From: Venkatesh Srinivas <me@acm.jhu.edu>
To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net>
Subject: Re: [9fans] kenfs question?
Date: Sun,  7 Feb 2010 07:19:00 -0500	[thread overview]
Message-ID: <f75780241002070419l2bc366c7mbc07b6d18a7bb46f@mail.gmail.com> (raw)
In-Reply-To: <7d9191a1033cef725ecab7ffc88d1d01@terzarima.net>

On Sun, Feb 7, 2010 at 5:42 AM, Charles Forsyth <forsyth@terzarima.net> wrote:
>> I guess I wasn't clear; what I was asking was why it was safe to
>> attempt to take a lock when splhi() at all.
>
> because such a lock is always taken with splhi, using ilock.
> you might find in older code the use of lock in interrupt handlers,
> protected by the implicit splhi of interrupt handling, and in
> a few cases explicit splhi calls before lock.

Ah, okay. I didn't realize that.

Perhaps it'd be clearer if ilock/iunlock took a different type than lock/unlock?

Thanks!
-- vs



      reply	other threads:[~2010-02-07 12:19 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-02-06 16:12 Venkatesh Srinivas
2010-02-06 16:16 ` erik quanstrom
2010-02-11 13:31   ` Venkatesh Srinivas
2010-02-11 14:55     ` erik quanstrom
2010-02-07  0:12 ` Russ Cox
2010-02-07  3:02   ` Venkatesh Srinivas
2010-02-07  4:44     ` erik quanstrom
2010-02-07 10:42       ` Charles Forsyth
2010-02-07 12:19         ` Venkatesh Srinivas [this message]

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