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authorKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>2011-07-06 09:43:16 -0400
committerKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>2011-07-07 12:19:08 -0400
commitee339fe63ac408e4604c1c88b1f9a428f2511b70 (patch)
treefc0ebf6e43de16750b07317f92d77cd350a2a709 /arch
parent155a16f21923bc2f04161ac92acca986371ef27b (diff)
xen/pci: Move check for acpi_sci_override_gsi to xen_setup_acpi_sci.
Previously we would check for acpi_sci_override_gsi == gsi every time a PCI device was enabled. That works during early bootup, but later on it could lead to triggering unnecessarily the acpi_gsi_to_irq(..) lookup. The reason is that acpi_sci_override_gsi was declared in __initdata and after early bootup could contain bogus values. This patch moves the check for acpi_sci_override_gsi to the site where the ACPI SCI is preset. CC: stable@kernel.org Reported-by: Raghavendra D Prabhu <rprabhu@wnohang.net> Tested-by: Raghavendra D Prabhu <rprabhu@wnohang.net> [http://lists.xensource.com/archives/html/xen-devel/2011-07/msg00154.html] Suggested-by: Ian Campbell <ijc@hellion.org.uk> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Diffstat (limited to 'arch')
-rw-r--r--arch/x86/pci/xen.c56
1 files changed, 28 insertions, 28 deletions
diff --git a/arch/x86/pci/xen.c b/arch/x86/pci/xen.c
index fe008309ffec..f567965c0620 100644
--- a/arch/x86/pci/xen.c
+++ b/arch/x86/pci/xen.c
@@ -327,13 +327,12 @@ int __init pci_xen_hvm_init(void)
}
#ifdef CONFIG_XEN_DOM0
-static int xen_register_pirq(u32 gsi, int triggering)
+static int xen_register_pirq(u32 gsi, int gsi_override, int triggering)
{
int rc, pirq, irq = -1;
struct physdev_map_pirq map_irq;
int shareable = 0;
char *name;
- bool gsi_override = false;
if (!xen_pv_domain())
return -1;
@@ -345,31 +344,12 @@ static int xen_register_pirq(u32 gsi, int triggering)
shareable = 1;
name = "ioapic-level";
}
-
pirq = xen_allocate_pirq_gsi(gsi);
if (pirq < 0)
goto out;
- /* Before we bind the GSI to a Linux IRQ, check whether
- * we need to override it with bus_irq (IRQ) value. Usually for
- * IRQs below IRQ_LEGACY_IRQ this holds IRQ == GSI, as so:
- * ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 9 low level)
- * but there are oddballs where the IRQ != GSI:
- * ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 20 low level)
- * which ends up being: gsi_to_irq[9] == 20
- * (which is what acpi_gsi_to_irq ends up calling when starting the
- * the ACPI interpreter and keels over since IRQ 9 has not been
- * setup as we had setup IRQ 20 for it).
- */
- if (gsi == acpi_sci_override_gsi) {
- /* Check whether the GSI != IRQ */
- acpi_gsi_to_irq(gsi, &irq);
- if (irq != gsi)
- /* Bugger, we MUST have that IRQ. */
- gsi_override = true;
- }
- if (gsi_override)
- irq = xen_bind_pirq_gsi_to_irq(irq, pirq, shareable, name);
+ if (gsi_override >= 0)
+ irq = xen_bind_pirq_gsi_to_irq(gsi_override, pirq, shareable, name);
else
irq = xen_bind_pirq_gsi_to_irq(gsi, pirq, shareable, name);
if (irq < 0)
@@ -392,7 +372,7 @@ out:
return irq;
}
-static int xen_register_gsi(u32 gsi, int triggering, int polarity)
+static int xen_register_gsi(u32 gsi, int gsi_override, int triggering, int polarity)
{
int rc, irq;
struct physdev_setup_gsi setup_gsi;
@@ -403,7 +383,7 @@ static int xen_register_gsi(u32 gsi, int triggering, int polarity)
printk(KERN_DEBUG "xen: registering gsi %u triggering %d polarity %d\n",
gsi, triggering, polarity);
- irq = xen_register_pirq(gsi, triggering);
+ irq = xen_register_pirq(gsi, gsi_override, triggering);
setup_gsi.gsi = gsi;
setup_gsi.triggering = (triggering == ACPI_EDGE_SENSITIVE ? 0 : 1);
@@ -425,6 +405,8 @@ static __init void xen_setup_acpi_sci(void)
int rc;
int trigger, polarity;
int gsi = acpi_sci_override_gsi;
+ int irq = -1;
+ int gsi_override = -1;
if (!gsi)
return;
@@ -441,7 +423,25 @@ static __init void xen_setup_acpi_sci(void)
printk(KERN_INFO "xen: sci override: global_irq=%d trigger=%d "
"polarity=%d\n", gsi, trigger, polarity);
- gsi = xen_register_gsi(gsi, trigger, polarity);
+ /* Before we bind the GSI to a Linux IRQ, check whether
+ * we need to override it with bus_irq (IRQ) value. Usually for
+ * IRQs below IRQ_LEGACY_IRQ this holds IRQ == GSI, as so:
+ * ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 9 low level)
+ * but there are oddballs where the IRQ != GSI:
+ * ACPI: INT_SRC_OVR (bus 0 bus_irq 9 global_irq 20 low level)
+ * which ends up being: gsi_to_irq[9] == 20
+ * (which is what acpi_gsi_to_irq ends up calling when starting the
+ * the ACPI interpreter and keels over since IRQ 9 has not been
+ * setup as we had setup IRQ 20 for it).
+ */
+ /* Check whether the GSI != IRQ */
+ if (acpi_gsi_to_irq(gsi, &irq) == 0) {
+ if (irq >= 0 && irq != gsi)
+ /* Bugger, we MUST have that IRQ. */
+ gsi_override = irq;
+ }
+
+ gsi = xen_register_gsi(gsi, gsi_override, trigger, polarity);
printk(KERN_INFO "xen: acpi sci %d\n", gsi);
return;
@@ -450,7 +450,7 @@ static __init void xen_setup_acpi_sci(void)
static int acpi_register_gsi_xen(struct device *dev, u32 gsi,
int trigger, int polarity)
{
- return xen_register_gsi(gsi, trigger, polarity);
+ return xen_register_gsi(gsi, -1 /* no GSI override */, trigger, polarity);
}
static int __init pci_xen_initial_domain(void)
@@ -489,7 +489,7 @@ void __init xen_setup_pirqs(void)
if (acpi_get_override_irq(irq, &trigger, &polarity) == -1)
continue;
- xen_register_pirq(irq,
+ xen_register_pirq(irq, -1 /* no GSI override */,
trigger ? ACPI_LEVEL_SENSITIVE : ACPI_EDGE_SENSITIVE);
}
}