From: Ming Lei <ming.lei@canonical.com>
To: Prarit Bhargava <prarit@redhat.com>
Cc: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
x86@kernel.org, herrmann.der.user@googlemail.com,
tigran@aivazian.fsnet.co.uk
Subject: Re: [PATCH 2/2] intel_microcode, Fix long microcode load time when firmware file is missing
Date: Mon, 21 Oct 2013 20:20:50 +0800 [thread overview]
Message-ID: <CACVXFVMjEnkk8zYycsk6t4WiWOJ_NT1AKFoK7p5mQnFkw9KE-g@mail.gmail.com> (raw)
In-Reply-To: <1382304926-1641-3-git-send-email-prarit@redhat.com>
On Mon, Oct 21, 2013 at 5:35 AM, Prarit Bhargava <prarit@redhat.com> wrote:
> If no firmware is found on the system that matches the processor, the
> microcode module can take hours to load. For example on recent kernels
> when loading the microcode module on an Intel system:
>
> [ 239.532116] microcode: CPU0 sig=0x306e4, pf=0x1, revision=0x413
> [ 299.693447] microcode: CPU1 sig=0x306e4, pf=0x1, revision=0x413
> [ 359.821972] microcode: CPU2 sig=0x306e4, pf=0x1, revision=0x413
> [ 419.960263] microcode: CPU3 sig=0x306e4, pf=0x1, revision=0x413
> [ 480.090024] microcode: CPU4 sig=0x306e4, pf=0x1, revision=0x413
> ...
> [ 2825.151364] microcode: CPU43 sig=0x306e4, pf=0x1, revision=0x413
> [ 2885.280863] microcode: CPU44 sig=0x306e4, pf=0x1, revision=0x413
> [ 2945.410719] microcode: CPU45 sig=0x306e4, pf=0x1, revision=0x413
> [ 3005.540541] microcode: CPU46 sig=0x306e4, pf=0x1, revision=0x413
> [ 3065.670405] microcode: CPU47 sig=0x306e4, pf=0x1, revision=0x413
> ...
> etc.
>
> Similarly there is a 60 second "hang" when loading the AMD module, which
> isn't as bad as the Intel situation, but it is a noticeable delay in the
> system boot and can be improved upon.
>
> Using request_firmware_nowait() seems more appropriate here and then we
> can avoid these delays, resulting in very quick load times for the
> microcode.
request_firmware_nowait() should be a good idea for the problem, but
why do you pass FW_ACTION_NOHOTPLUG as uevent? It is used now
by drivers which requires their own user-space applications to handle
the request by polling the firmware device under sysfs.
So I am wondering if your microcode case belongs to the above case
of FW_ACTION_NOHOTPLUG?
And why don't you pass FW_ACTION_HOTPLUG? and you are sure
that udev isn't required to handle your microcode update request?
Thanks,
--
Ming Lei
next prev parent reply other threads:[~2013-10-21 12:20 UTC|newest]
Thread overview: 22+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-10-20 21:35 [PATCH 0/2] Improve firmware loading times on AMD and Intel Prarit Bhargava
2013-10-20 21:35 ` [PATCH 1/2] firmware, fix request_firmware_nowait() freeze with no uevent Prarit Bhargava
2013-10-21 12:24 ` Ming Lei
2013-10-21 22:24 ` Prarit Bhargava
2013-10-22 2:35 ` Ming Lei
2013-10-22 23:15 ` Prarit Bhargava
2013-10-23 4:16 ` Ming Lei
2013-10-23 10:36 ` Prarit Bhargava
2013-10-23 12:02 ` Prarit Bhargava
2013-10-23 13:21 ` Ming Lei
2013-10-23 14:08 ` Prarit Bhargava
2013-10-24 1:54 ` Ming Lei
2013-10-24 11:17 ` Henrique de Moraes Holschuh
2013-10-24 12:05 ` Prarit Bhargava
2013-10-20 21:35 ` [PATCH 2/2] intel_microcode, Fix long microcode load time when firmware file is missing Prarit Bhargava
2013-10-21 12:20 ` Ming Lei [this message]
2013-10-21 12:26 ` Prarit Bhargava
2013-10-21 12:32 ` Ming Lei
2013-10-21 14:25 ` Prarit Bhargava
2013-10-22 2:43 ` Ming Lei
2013-10-22 23:16 ` Prarit Bhargava
2013-10-20 22:58 ` [PATCH 0/2] Improve firmware loading times on AMD and Intel Andi Kleen
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