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From: Marcelo Tosatti <mtosatti@redhat.com>
To: kvm@vger.kernel.org
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Subject: [patch 3/8] test: protect fwcfg accesses with lock
Date: Wed, 24 Mar 2010 18:24:11 -0300	[thread overview]
Message-ID: <20100324212725.912860027@amt.cnet> (raw)
In-Reply-To: 20100324212408.790319364@amt.cnet

[-- Attachment #1: fwcfg-lock --]
[-- Type: text/plain, Size: 849 bytes --]

So multiple CPU's can access fwcfg safely.

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

Index: qemu-kvm/kvm/user/test/lib/x86/fwcfg.c
===================================================================
--- qemu-kvm.orig/kvm/user/test/lib/x86/fwcfg.c
+++ qemu-kvm/kvm/user/test/lib/x86/fwcfg.c
@@ -1,4 +1,7 @@
 #include "fwcfg.h"
+#include "smp.h"
+
+static struct spinlock lock;
 
 uint64_t fwcfg_get_u(uint16_t index, int bytes)
 {
@@ -6,11 +9,13 @@ uint64_t fwcfg_get_u(uint16_t index, int
     uint8_t b;
     int i;
 
+    spin_lock(&lock);
     asm volatile ("out %0, %1" : : "a"(index), "d"((uint16_t)BIOS_CFG_IOPORT));
     for (i = 0; i < bytes; ++i) {
         asm volatile ("in %1, %0" : "=a"(b) : "d"((uint16_t)(BIOS_CFG_IOPORT + 1)));
         r |= (uint64_t)b << (i * 8);
     }
+    spin_unlock(&lock);
     return r;
 }
 



  parent reply	other threads:[~2010-03-24 21:29 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-03-24 21:24 [patch 0/8] add slot deletion, rmap chain tests Marcelo Tosatti
2010-03-24 21:24 ` [patch 1/8] test: allow functions to execute on non-irq context remotely Marcelo Tosatti
2010-03-25 16:25   ` Avi Kivity
2010-03-25 18:07     ` Marcelo Tosatti
2010-03-28  6:32       ` Avi Kivity
2010-03-24 21:24 ` [patch 2/8] test: add pagefault exception handler Marcelo Tosatti
2010-03-24 21:24 ` Marcelo Tosatti [this message]
2010-03-24 21:24 ` [patch 4/8] test: export vm helpers Marcelo Tosatti
2010-03-24 21:24 ` [patch 5/8] testdev: add port to create/delete memslots Marcelo Tosatti
2010-03-25 16:27   ` Avi Kivity
2010-03-24 21:24 ` [patch 6/8] test: parallel faults vs slot deletion Marcelo Tosatti
2010-03-24 21:24 ` [patch 7/8] test: bump max vcpus to 64 Marcelo Tosatti
2010-03-24 21:24 ` [patch 8/8] test: long rmap chains Marcelo Tosatti

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