Skip site navigation (1)Skip section navigation (2)
Date:      Wed, 1 May 2002 13:47:32 -0400 (EDT)
From:      Andrew Gallatin <gallatin@cs.duke.edu>
To:        Terry Lambert <tlambert2@mindspring.com>
Cc:        freebsd-smp@freebsd.org
Subject:   Re: hlt when idle?
Message-ID:  <15568.10804.364425.409745@grasshopper.cs.duke.edu>
In-Reply-To: <3CD022A2.FACD21E9@mindspring.com>
References:  <15567.62317.677224.3470@grasshopper.cs.duke.edu> <3CD022A2.FACD21E9@mindspring.com>

next in thread | previous in thread | raw e-mail | index | archive | help

Terry Lambert writes:
 > Andrew Gallatin wrote:
 > > Can somebody remind me why we do not hlt in the idle loop on MP x86s?
 > 
 > Halting with "giant" and/or "the scheduler lock" held is bad.

Ug.  We hold locks in the idle loop??

 > > Do both CPUs get clock interrupts on x86?
 > 
 > The clock interrupts may or may not be routed via the APIC;
 > routing of the clock interrupt is one of the most common
 > bogosities that you have to handle on x86 SMP systems; there
 > is a special printf for complaining about having to work
 > around broken BIOS and/or motherboard circuitry.

Is this what you mean:

   APIC_IO: Testing 8254 interrupt delivery
   APIC_IO: Broken MP table detected: 8254 is not connected to IOAPIC #0 intpin 2
   APIC_IO: routing 8254 via 8259 and IOAPIC #0 intpin 0

This was taken from the machine which seems to work just fine with
halting in the idle loop... (Serverworks LE based SuperMicro 370DLE)

Drew


To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-smp" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?15568.10804.364425.409745>