[Xen-changelog] [xen stable-4.1] AMD/IOMMU: Process softirqs while building dom0 iommu mappings

[patchbot@xxxxxxx]

commit dafb4bd5885ca66040094b5d79e053e245d587df
Author:     Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
AuthorDate: Tue Apr 2 12:27:20 2013 +0200
Commit:     Jan Beulich <jbeulich@xxxxxxxx>
CommitDate: Tue Apr 2 12:27:20 2013 +0200

    AMD/IOMMU: Process softirqs while building dom0 iommu mappings
    
    Recent changes which have made their way into xen-4.2 stable have pushed the
    runtime of construct_dom0() over 5 seconds, which has caused regressions in
    XenServer testing because of our 5 second watchdog.
    
    The root cause is that amd_iommu_dom0_init() does not process softirqs and 
in
    particular the nmi_timer which causes the watchdog to decide that no useful
    progress is being made.
    
    This patch adds periodic calls to process_pending_softirqs() at the same
    interval as the Intel variant of this function.  The server which was 
failing
    with the watchdog test now boots reliably with a timeout of 1 second.
    
    Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
    master changeset: 0f7b6f91ac1bbfd33b23c291b14874b9561909d2
    master date: 2013-03-20 10:00:01 +0100
---
 xen/drivers/passthrough/amd/pci_amd_iommu.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)

diff --git a/xen/drivers/passthrough/amd/pci_amd_iommu.c 
b/xen/drivers/passthrough/amd/pci_amd_iommu.c
index 21b7460..43175cd 100644
--- a/xen/drivers/passthrough/amd/pci_amd_iommu.c
+++ b/xen/drivers/passthrough/amd/pci_amd_iommu.c
@@ -21,6 +21,7 @@
 #include <xen/sched.h>
 #include <xen/pci.h>
 #include <xen/pci_regs.h>
+#include <xen/softirq.h>
 #include <asm/hvm/iommu.h>
 #include <asm/amd-iommu.h>
 #include <asm/hvm/svm/amd-iommu-proto.h>
@@ -271,6 +272,9 @@ static void __init amd_iommu_dom0_init(struct domain *d)
              * a pfn_valid() check would seem desirable here.
              */
             amd_iommu_map_page(d, pfn, pfn, IOMMUF_readable|IOMMUF_writable);
+
+            if ( !(i & 0xfffff) )
+                process_pending_softirqs();
         }
     }
 
--
generated by git-patchbot for /home/xen/git/xen.git#stable-4.1

_______________________________________________
Xen-changelog mailing list
Xen-changelog@xxxxxxxxxxxxx
http://lists.xensource.com/xen-changelog