xen: support pirq_eoi_map
The pirq_eoi_map is a bitmap offered by Xen to check which pirqs need to
be EOI'd without having to issue an hypercall every time.
We use PHYSDEVOP_pirq_eoi_gmfn_v2 to map the bitmap, then if we
succeed we use pirq_eoi_map to check whether pirqs need eoi.
Changes in v3:
- explicitly use PHYSDEVOP_pirq_eoi_gmfn_v2 rather than
PHYSDEVOP_pirq_eoi_gmfn;
- introduce pirq_check_eoi_map, a function to check if a pirq needs an
eoi using the map;
-rename pirq_needs_eoi into pirq_needs_eoi_flag;
- introduce a function pointer called pirq_needs_eoi that is going to be
set to the right implementation depending on the availability of
PHYSDEVOP_pirq_eoi_gmfn_v2.
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
diff --git a/drivers/xen/events.c b/drivers/xen/events.c
index e5e5812..4b33acd 100644
--- a/drivers/xen/events.c
+++ b/drivers/xen/events.c
@@ -37,6 +37,7 @@
#include <asm/idle.h>
#include <asm/io_apic.h>
#include <asm/sync_bitops.h>
+#include <asm/xen/page.h>
#include <asm/xen/pci.h>
#include <asm/xen/hypercall.h>
#include <asm/xen/hypervisor.h>
@@ -109,6 +110,8 @@
#define PIRQ_SHAREABLE (1 << 1)
static int *evtchn_to_irq;
+static unsigned long *pirq_eoi_map;
+static bool (*pirq_needs_eoi)(unsigned irq);
static DEFINE_PER_CPU(unsigned long [NR_EVENT_CHANNELS/BITS_PER_LONG],
cpu_evtchn_mask);
@@ -269,10 +272,14 @@
return ret;
}
-static bool pirq_needs_eoi(unsigned irq)
+static bool pirq_check_eoi_map(unsigned irq)
+{
+ return test_bit(irq, pirq_eoi_map);
+}
+
+static bool pirq_needs_eoi_flag(unsigned irq)
{
struct irq_info *info = info_for_irq(irq);
-
BUG_ON(info->type != IRQT_PIRQ);
return info->u.pirq.flags & PIRQ_NEEDS_EOI;
@@ -1768,7 +1775,7 @@
void __init xen_init_IRQ(void)
{
- int i;
+ int i, rc;
evtchn_to_irq = kcalloc(NR_EVENT_CHANNELS, sizeof(*evtchn_to_irq),
GFP_KERNEL);
@@ -1782,6 +1789,8 @@
for (i = 0; i < NR_EVENT_CHANNELS; i++)
mask_evtchn(i);
+ pirq_needs_eoi = pirq_needs_eoi_flag;
+
if (xen_hvm_domain()) {
xen_callback_vector();
native_init_IRQ();
@@ -1789,8 +1798,19 @@
* __acpi_register_gsi can point at the right function */
pci_xen_hvm_init();
} else {
+ struct physdev_pirq_eoi_gmfn eoi_gmfn;
+
irq_ctx_init(smp_processor_id());
if (xen_initial_domain())
pci_xen_initial_domain();
+
+ pirq_eoi_map = (void *)__get_free_page(GFP_KERNEL|__GFP_ZERO);
+ eoi_gmfn.gmfn = virt_to_mfn(pirq_eoi_map);
+ rc = HYPERVISOR_physdev_op(PHYSDEVOP_pirq_eoi_gmfn_v2, &eoi_gmfn);
+ if (rc != 0) {
+ free_page((unsigned long) pirq_eoi_map);
+ pirq_eoi_map = NULL;
+ } else
+ pirq_needs_eoi = pirq_check_eoi_map;
}
}