lkml.org 
[lkml]   [2009]   [Mar]   [24]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[tip:x86/apic] x86: Correct behaviour of irq affinity
Commit-ID:  85a328f27b927e3f42563c76e1a6992068100433
Gitweb: http://git.kernel.org/tip/85a328f27b927e3f42563c76e1a6992068100433
Author: Rusty Russell <rusty@rustcorp.com.au>
AuthorDate: Tue, 24 Mar 2009 14:17:19 -0700
Committer: Ingo Molnar <mingo@elte.hu>
CommitDate: Tue, 24 Mar 2009 22:28:39 +0100

x86: Correct behaviour of irq affinity

Impact: get correct smp_affinity as user requested

The effect of setting desc->affinity (ie. from userspace via sysfs) has
varied over time. In 2.6.27, the 32-bit code anded the value with
cpu_online_map, and both 32 and 64-bit did that anding whenever a cpu
was unplugged.

2.6.29 consolidated this into one routine (and fixed hotplug) but
introduced another variation: anding the affinity with cfg->domain.

We should just set it to what the user said - if possible.

(cpu_mask_to_apicid_and already takes cpu_online_mask into account)

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
LKML-Reference: <49C94DDF.2010703@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>


---
arch/x86/kernel/apic/io_apic.c | 5 +++--
1 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/apic/io_apic.c b/arch/x86/kernel/apic/io_apic.c
index 1ed6c06..91476aa 100644
--- a/arch/x86/kernel/apic/io_apic.c
+++ b/arch/x86/kernel/apic/io_apic.c
@@ -594,9 +594,10 @@ set_desc_affinity(struct irq_desc *desc, const struct cpumask *mask)

/* check that before desc->addinity get updated */
set_extra_move_desc(desc, mask);
- cpumask_and(desc->affinity, cfg->domain, mask);

- return apic->cpu_mask_to_apicid_and(desc->affinity, cpu_online_mask);
+ cpumask_copy(desc->affinity, mask);
+
+ return apic->cpu_mask_to_apicid_and(desc->affinity, cfg->cpu_domain);
}

static void

\
 
 \ /
  Last update: 2009-03-24 22:37    [W:0.043 / U:0.604 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site