git: ac959cf54421 - main - xen: introduce xen_has_percpu_evtchn()

[Roger Pau Monné]

The branch main has been updated by royger:

URL: https://cgit.FreeBSD.org/src/commit/?id=ac959cf54421bc560c93748b227f05f9b6583678

commit ac959cf54421bc560c93748b227f05f9b6583678
Author:     Julien Grall <julien at xen.org>
AuthorDate: 2015-10-10 19:40:06 +0000
Commit:     Roger Pau Monné <royger at FreeBSD.org>
CommitDate: 2021-07-28 15:27:05 +0000

    xen: introduce xen_has_percpu_evtchn()
    
    xen_vector_callback_enabled is x86 specific and availability of
    per-cpu event channel delivery differs on other architectures.
    
    Introduce a new helper to check if there's support for per-cpu event
    channel injection.
    
    Submitted by: Elliott Mitchell <ehem+freebsd at m5p.com>
    Reviewed by: royger
    Differential Revision: https://reviews.freebsd.org/D29402
---
 sys/dev/xen/debug/debug.c    | 2 +-
 sys/x86/include/xen/xen-os.h | 7 +++++++
 sys/x86/xen/xen_intr.c       | 4 ++--
 3 files changed, 10 insertions(+), 3 deletions(-)

diff --git a/sys/dev/xen/debug/debug.c b/sys/dev/xen/debug/debug.c
index 269d46d46afa..ec4585e64c62 100644
--- a/sys/dev/xen/debug/debug.c
+++ b/sys/dev/xen/debug/debug.c
@@ -97,7 +97,7 @@ xendebug_identify(driver_t *driver, device_t parent)
 	KASSERT(xen_domain(),
 	    ("Trying to add Xen debug device to non-xen guest"));
 
-	if (xen_hvm_domain() && !xen_vector_callback_enabled)
+	if (!xen_has_percpu_evtchn())
 		return;
 
 	if (BUS_ADD_CHILD(parent, 0, "debug", 0) == NULL)
diff --git a/sys/x86/include/xen/xen-os.h b/sys/x86/include/xen/xen-os.h
index 5b3b912e0891..9d0964c6631d 100644
--- a/sys/x86/include/xen/xen-os.h
+++ b/sys/x86/include/xen/xen-os.h
@@ -49,6 +49,13 @@ extern int xen_disable_pv_disks;
 /* tunable for disabling PV nics */
 extern int xen_disable_pv_nics;
 
+static inline bool
+xen_has_percpu_evtchn(void)
+{
+
+	return (!xen_hvm_domain() || xen_vector_callback_enabled);
+}
+
 static inline bool
 xen_pv_shutdown_handler(void)
 {
diff --git a/sys/x86/xen/xen_intr.c b/sys/x86/xen/xen_intr.c
index bab86ccd295a..a3d84965f0f2 100644
--- a/sys/x86/xen/xen_intr.c
+++ b/sys/x86/xen/xen_intr.c
@@ -510,7 +510,7 @@ xen_intr_handle_upcall(struct trapframe *trap_frame)
 	s   = HYPERVISOR_shared_info;
 	v   = DPCPU_GET(vcpu_info);
 
-	if (xen_hvm_domain() && !xen_vector_callback_enabled) {
+	if (!xen_has_percpu_evtchn()) {
 		KASSERT((cpu == 0), ("Fired PCI event callback on wrong CPU"));
 	}
 
@@ -859,7 +859,7 @@ xen_intr_assign_cpu(struct intsrc *base_isrc, u_int apic_id)
 	u_int to_cpu, vcpu_id;
 	int error, masked;
 
-	if (xen_vector_callback_enabled == 0)
+	if (!xen_has_percpu_evtchn())
 		return (EOPNOTSUPP);
 
 	to_cpu = apic_cpuid(apic_id);