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From: jinjun gao <gjinjun@gmail.com>
Date: Mon, 26 Dec 2016 18:26:48 +0800
Message-ID: <CAORc1LBjzrADNr5_-zg1nt5qDRPVRyzUpRQxkuWCOMtb2QG9dQ@mail.gmail.com>
Subject: Why need not to PROC_UNLOCK() in kthread_suspend()/kproc_suspend()?
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Hi Guys,

In file sys/kern/kern_kthread.c (
https://github.com/freebsd/freebsd/blob/master/sys/kern/kern_kthread.c),
the PROC_LOCK() and PROC_UNLOCK() are used in pairs in one function except
function kthread_suspend()/kproc_suspend() (
https://github.com/freebsd/freebsd/blob/master/sys/kern/kern_kthread.c#L177).
In these two functions, there is only PROC_LOCK(). I checked may related
function(such as kproc_resume()) and can not find PROC_UNLOCK() to pair the
one resided in kproc_suspend().  Why need not PROC_UNLOCK() to pair
PROC_LOCK() in kproc_suspend()/kthread_suspend()? Thanks!


regards,
Jinjun