From: Thomas Gleixner <tglx@linutronix.de>
To: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com>
Cc: peterz@infradead.org, paulmck@linux.vnet.ibm.com,
rusty@rustcorp.com.au, mingo@kernel.org, yong.zhang0@gmail.com,
akpm@linux-foundation.org, vatsa@linux.vnet.ibm.com, rjw@sisk.pl,
linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org,
"Nikunj A. Dadhania" <nikunj@linux.vnet.ibm.com>"Nikunj A.
Dadhania" <nikunj@linux.vnet.ibm.com>,
Ingo Molnar <mingo@redhat.com>, "H. Peter Anvin" <hpa@zytor.com>,
x86@kernel.org, Suresh Siddha <suresh.b.siddha@intel.com>,
Joerg Roedel <joerg.roedel@amd.com>,
Yinghai Lu <yinghai@kernel.org>,
Naga Chumbalkar <nagananda.chumbalkar@hp.com>,
Don Zickus <dzickus@redhat.com>,
Paul Gortmaker <paul.gortmaker@windriver.com>,
Peter Zijlstra <a.p.zijlstra@chello.nl>
Subject: Re: [PATCH 07/27] x86, smpboot: Use generic SMP booting infrastructure
Date: Mon, 4 Jun 2012 16:29:57 +0200 (CEST) [thread overview]
Message-ID: <alpine.LFD.2.02.1206041613380.3086@ionos> (raw)
In-Reply-To: <20120601091148.31979.53116.stgit@srivatsabhat.in.ibm.com>
On Fri, 1 Jun 2012, Srivatsa S. Bhat wrote:
> From: Nikunj A. Dadhania <nikunj@linux.vnet.ibm.com>
>
> Convert x86 to use the generic framework to boot secondary CPUs.
>
> Notes:
> 1. x86 manipulates the cpu_online_mask under vector_lock. So, while
> converting over to the generic smp booting code, override arch_vector_lock()
> and arch_vector_unlock() to lock_vector_lock() and unlock_vector_lock()
> respectively.
>
> 2. In smp_callin(), we allow the master to continue as soon as the physical
> booting of the secondary processor is done. That is, we don't wait till the
> CPU_STARTING notifications are sent.
>
> Implications:
> - This does not alter the order in which the notifications are sent (i.e.,
> still CPU_STARTING is followed by CPU_ONLINE) because the master waits till
> the new cpu is set in the cpu_online_mask before returning to generic code.
>
> - This approach is better because of 2 reasons:
> a. It makes more sense: the master has a timeout for waiting on the
> cpu_callin_map - which means we should report back as soon as possible.
> The whole idea of having a timeout is to estimate the maximum time that
> could be taken for physical booting. This approach separates out the
> physical booting vs running CPU hotplug callbacks and reports back to
> the master as soon as physical booting is done.
How do you deal with the problem that the master does not come back in
time? There is a timeout on the booting side as well. I haven't found
out why this timeout exists at all, but we need to take care of that
and there is a patch on LKML which removes the panic as this can
happen on virt. I really wonder whether the hardware for which this
timeout stuff was introduced still exists or whether we can simply get
rid of it completely.
Also the whole callin/callout mask business wants to be in the generic
code. It can be replaced completely by cpu_state, at least that's what
I was aiming for. There is no need for several variables tracking the
same thing in different ways.
Thanks,
tglx
next prev parent reply other threads:[~2012-06-04 14:30 UTC|newest]
Thread overview: 125+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-06-01 9:10 [PATCH 00/27] Generic framework for SMP booting/CPU hotplug related code Srivatsa S. Bhat
2012-06-01 9:10 ` [PATCH 01/27] smpboot: Provide a generic method to boot secondary processors Srivatsa S. Bhat
2012-06-01 9:10 ` Srivatsa S. Bhat
2012-06-01 16:51 ` Sam Ravnborg
2012-06-01 22:29 ` Srivatsa S. Bhat
2012-06-04 10:32 ` Thomas Gleixner
2012-06-04 13:07 ` Srivatsa S. Bhat
2012-06-04 13:18 ` Thomas Gleixner
2012-06-04 13:18 ` Thomas Gleixner
2012-06-04 16:53 ` Srivatsa S. Bhat
2012-06-05 5:11 ` Yong Zhang
2012-06-05 6:07 ` Srivatsa S. Bhat
2012-06-01 16:53 ` Sam Ravnborg
2012-06-01 22:41 ` Srivatsa S. Bhat
2012-06-02 15:16 ` Sam Ravnborg
2012-06-02 15:34 ` Srivatsa S. Bhat
2012-06-01 9:10 ` [PATCH 02/27] smpboot: Add provisions for arch-specific locking around cpu_online_mask Srivatsa S. Bhat
2012-06-01 9:10 ` Srivatsa S. Bhat
2012-06-01 9:10 ` [PATCH 03/27] smpboot: Define and use cpu_state per-cpu variable in generic code Srivatsa S. Bhat
2012-06-01 16:59 ` David Daney
2012-06-01 9:11 ` [PATCH 04/27] smpboot, x86, xen: Determine smp booting implementations at run-time Srivatsa S. Bhat
2012-06-01 9:11 ` Srivatsa S. Bhat
2012-06-01 9:11 ` [PATCH 05/27] xen, cpu hotplug: Don't call cpu_bringup() in xen_play_dead() Srivatsa S. Bhat
2012-06-01 9:11 ` Srivatsa S. Bhat
2012-06-01 12:59 ` [Xen-devel] " Jan Beulich
2012-06-01 15:13 ` Srivatsa S. Bhat
2012-06-01 15:36 ` Jan Beulich
2012-06-02 18:06 ` Srivatsa S. Bhat
2012-06-02 18:06 ` Srivatsa S. Bhat
2012-06-05 16:49 ` Konrad Rzeszutek Wilk
2012-06-05 16:49 ` Konrad Rzeszutek Wilk
2012-06-05 17:36 ` Srivatsa S. Bhat
2012-06-05 17:40 ` Thomas Gleixner
2012-06-05 17:40 ` Thomas Gleixner
2012-06-05 17:48 ` Srivatsa S. Bhat
2012-06-05 17:48 ` Srivatsa S. Bhat
2012-06-01 9:11 ` [PATCH 06/27] xen, smpboot: Use generic SMP booting infrastructure Srivatsa S. Bhat
2012-06-01 9:11 ` Srivatsa S. Bhat
2012-06-01 9:11 ` [PATCH 07/27] x86, " Srivatsa S. Bhat
2012-06-01 9:11 ` Srivatsa S. Bhat
2012-06-04 14:29 ` Thomas Gleixner [this message]
2012-06-04 17:00 ` Srivatsa S. Bhat
2012-06-01 9:12 ` [PATCH 08/27] m32r: Fix horrible logic in smp_prepare_cpus() Srivatsa S. Bhat
2012-06-01 9:12 ` Srivatsa S. Bhat
2012-06-01 9:12 ` [PATCH 09/27] m32r, smpboot: Use generic SMP booting infrastructure Srivatsa S. Bhat
2012-06-01 9:12 ` Srivatsa S. Bhat
2012-06-01 9:12 ` [PATCH 10/27] mips, " Srivatsa S. Bhat
2012-06-01 9:12 ` Srivatsa S. Bhat
2012-06-03 8:25 ` Yong Zhang
2012-06-03 11:48 ` Srivatsa S. Bhat
2012-06-04 2:17 ` Yong Zhang
2012-06-01 9:12 ` [PATCH 11/27] sh, " Srivatsa S. Bhat
2012-06-01 9:12 ` Srivatsa S. Bhat
2012-06-01 9:12 ` [PATCH 12/27] tile, " Srivatsa S. Bhat
2012-06-01 9:12 ` Srivatsa S. Bhat
2012-06-01 18:07 ` Chris Metcalf
2012-06-01 9:13 ` [PATCH 13/27] hexagon, " Srivatsa S. Bhat
2012-06-01 9:13 ` Srivatsa S. Bhat
2012-06-01 9:13 ` [PATCH 14/27] ia64: Move holding of vector_lock to __setup_vector_irq() Srivatsa S. Bhat
2012-06-01 9:13 ` Srivatsa S. Bhat
2012-06-01 9:13 ` [PATCH 15/27] ia64, smpboot: Use generic SMP booting infrastructure Srivatsa S. Bhat
2012-06-01 9:13 ` Srivatsa S. Bhat
2012-06-01 9:13 ` [PATCH 16/27] mn10300: Fix horrible logic in smp_prepare_cpus() Srivatsa S. Bhat
2012-06-01 9:13 ` Srivatsa S. Bhat
2012-06-01 9:14 ` [PATCH 17/27] mn10300, smpboot: Use generic SMP booting infrastructure Srivatsa S. Bhat
2012-06-01 9:14 ` Srivatsa S. Bhat
2012-06-03 8:33 ` Yong Zhang
2012-06-03 8:33 ` Yong Zhang
2012-06-03 11:50 ` Srivatsa S. Bhat
2012-06-01 9:14 ` [PATCH 18/27] powerpc, " Srivatsa S. Bhat
2012-06-01 9:14 ` Srivatsa S. Bhat
2012-06-02 6:14 ` Paul Mackerras
2012-06-02 6:14 ` Paul Mackerras
2012-06-01 9:14 ` [PATCH 19/27] blackfin, " Srivatsa S. Bhat
2012-06-01 9:14 ` Srivatsa S. Bhat
2012-06-01 9:14 ` [PATCH 20/27] sparc64, " Srivatsa S. Bhat
2012-06-01 9:14 ` Srivatsa S. Bhat
2012-06-01 17:55 ` David Miller
2012-06-01 22:44 ` [UPDATED PATCH " Srivatsa S. Bhat
2012-06-01 22:44 ` Srivatsa S. Bhat
2012-06-01 22:52 ` David Miller
2012-06-01 22:52 ` David Miller
2012-06-01 9:15 ` [PATCH 21/27] sparc32, " Srivatsa S. Bhat
2012-06-01 9:15 ` Srivatsa S. Bhat
2012-06-01 17:56 ` David Miller
2012-06-01 17:56 ` David Miller
2012-06-01 18:54 ` Sam Ravnborg
2012-06-01 18:54 ` Sam Ravnborg
2012-06-01 22:47 ` [UPDATED PATCH " Srivatsa S. Bhat
2012-06-01 22:53 ` David Miller
2012-06-01 22:53 ` David Miller
2012-06-01 23:17 ` Srivatsa S. Bhat
2012-06-01 23:17 ` Srivatsa S. Bhat
2012-06-02 6:52 ` Sam Ravnborg
2012-06-02 7:44 ` Sam Ravnborg
2012-06-02 8:01 ` Srivatsa S. Bhat
2012-06-02 8:01 ` Srivatsa S. Bhat
2012-06-02 8:14 ` Srivatsa S. Bhat
2012-06-02 15:13 ` Sam Ravnborg
2012-06-02 15:13 ` Sam Ravnborg
2012-06-02 15:58 ` Srivatsa S. Bhat
2012-06-02 16:23 ` Sam Ravnborg
2012-06-02 16:34 ` Srivatsa S. Bhat
2012-06-03 21:17 ` [PATCH] sparc32: refactor smp boot Sam Ravnborg
2012-06-03 21:17 ` Sam Ravnborg
2012-06-04 1:04 ` David Miller
2012-06-04 1:04 ` David Miller
2012-06-04 6:48 ` Srivatsa S. Bhat
2012-06-01 9:15 ` [PATCH 22/27] um, smpboot: Use generic SMP booting infrastructure Srivatsa S. Bhat
2012-06-01 9:15 ` Srivatsa S. Bhat
2012-06-01 9:15 ` [PATCH 23/27] cris, " Srivatsa S. Bhat
2012-06-01 9:15 ` Srivatsa S. Bhat
2012-06-03 8:41 ` Yong Zhang
2012-06-03 8:41 ` Yong Zhang
2012-06-03 11:52 ` Srivatsa S. Bhat
2012-06-01 9:15 ` [PATCH 24/27] parisc, " Srivatsa S. Bhat
2012-06-01 9:15 ` Srivatsa S. Bhat
2012-06-01 9:16 ` [PATCH 25/27] s390, " Srivatsa S. Bhat
2012-06-01 9:16 ` Srivatsa S. Bhat
2012-06-01 10:45 ` Heiko Carstens
2012-06-01 9:16 ` [PATCH 26/27] arm, " Srivatsa S. Bhat
2012-06-01 9:16 ` Srivatsa S. Bhat
2012-06-01 11:04 ` Russell King - ARM Linux
2012-06-01 9:16 ` [PATCH 27/27] alpha, " Srivatsa S. Bhat
2012-06-01 9:16 ` Srivatsa S. Bhat
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