[PATCH] [next] KVM: lapic: allow setting apic debug dynamically

From: Yi Wang
Date: Tue May 07 2019 - 02:36:41 EST


There are many functions invoke apic_debug(), which is defined
as a null function by default, and that's incovenient for debuging
lapic.

This patch allows setting apic debug according to add a apic_dbg
parameter of kvm.

Signed-off-by: Yi Wang <wang.yi59@xxxxxxxxxx>
---
arch/x86/kvm/lapic.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 9bf70cf..4d8f10f 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -54,8 +54,13 @@
#define PRIu64 "u"
#define PRIo64 "o"

+static int apic_dbg;
+module_param(apic_dbg, bool, 0644);
+
/* #define apic_debug(fmt,arg...) printk(KERN_WARNING fmt,##arg) */
-#define apic_debug(fmt, arg...) do {} while (0)
+#define apic_debug(fmt, arg...) do { if (apic_dbg) \
+ printk(KERN_DEBUG fmt, ##arg); \
+} while (0)

/* 14 is the version for Xeon and Pentium 8.4.8*/
#define APIC_VERSION (0x14UL | ((KVM_APIC_LVT_NUM - 1) << 16))
--
1.8.3.1