Use the tracing infrastructure helper __print_flags() for printing flag
bitfields, to enhance the trace output by displaying a string describing
each of the inhibit reasons set.
The kvm_apicv_inhibit_changed tracepoint currently shows the raw bitmap
value, requiring the user to consult the source file where the inhibit
reasons are defined to decode the trace output.
Co-developed-by: Sean Christopherson <seanjc@xxxxxxxxxx>
Signed-off-by: Alejandro Jimenez <alejandro.j.jimenez@xxxxxxxxxx>
---
arch/x86/include/asm/kvm_host.h | 19 +++++++++++++++++++
arch/x86/kvm/trace.h | 9 +++++++--
arch/x86/kvm/x86.c | 4 ++++
3 files changed, 30 insertions(+), 2 deletions(-)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 1d13e3cd1dc5..08f83efd12ff 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1273,8 +1273,27 @@ enum kvm_apicv_inhibit {
* mapping between logical ID and vCPU.
*/
APICV_INHIBIT_REASON_LOGICAL_ID_ALIASED,
+
+ NR_APICV_INHIBIT_REASONS,
};
+#define __APICV_INHIBIT_REASON(reason) \
+ { BIT(APICV_INHIBIT_REASON_##reason), #reason }
+
+#define APICV_INHIBIT_REASONS \
+ __APICV_INHIBIT_REASON(DISABLE), \
+ __APICV_INHIBIT_REASON(HYPERV), \
+ __APICV_INHIBIT_REASON(ABSENT), \
+ __APICV_INHIBIT_REASON(BLOCKIRQ), \
+ __APICV_INHIBIT_REASON(PHYSICAL_ID_ALIASED), \
+ __APICV_INHIBIT_REASON(APIC_ID_MODIFIED), \
+ __APICV_INHIBIT_REASON(APIC_BASE_MODIFIED), \
+ __APICV_INHIBIT_REASON(NESTED), \
+ __APICV_INHIBIT_REASON(IRQWIN), \
+ __APICV_INHIBIT_REASON(PIT_REINJ), \
+ __APICV_INHIBIT_REASON(SEV), \
+ __APICV_INHIBIT_REASON(LOGICAL_ID_ALIASED)
+
struct kvm_arch {
unsigned long n_used_mmu_pages;
unsigned long n_requested_mmu_pages;
diff --git a/arch/x86/kvm/trace.h b/arch/x86/kvm/trace.h
index 9d0b02ef307e..f23fb9a6776e 100644
--- a/arch/x86/kvm/trace.h
+++ b/arch/x86/kvm/trace.h
@@ -1375,6 +1375,10 @@ TRACE_EVENT(kvm_hv_stimer_cleanup,
__entry->vcpu_id, __entry->timer_index)
);
+#define kvm_print_apicv_inhibit_reasons(inhibits) \
+ (inhibits), (inhibits) ? " " : "", \
+ (inhibits) ? __print_flags(inhibits, "|", APICV_INHIBIT_REASONS) : ""
+
TRACE_EVENT(kvm_apicv_inhibit_changed,
TP_PROTO(int reason, bool set, unsigned long inhibits),
TP_ARGS(reason, set, inhibits),
@@ -1391,9 +1395,10 @@ TRACE_EVENT(kvm_apicv_inhibit_changed,
__entry->inhibits = inhibits;
),
- TP_printk("%s reason=%u, inhibits=0x%lx",
+ TP_printk("%s reason=%u, inhibits=0x%lx%s%s",
__entry->set ? "set" : "cleared",
- __entry->reason, __entry->inhibits)
+ __entry->reason,
+ kvm_print_apicv_inhibit_reasons(__entry->inhibits))
);
TRACE_EVENT(kvm_apicv_accept_irq,
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index b389129d59a9..597ff748f955 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -10011,6 +10011,10 @@ EXPORT_SYMBOL_GPL(kvm_vcpu_apicv_activated);
static void set_or_clear_apicv_inhibit(unsigned long *inhibits,
enum kvm_apicv_inhibit reason, bool set)
{
+ const struct trace_print_flags apicv_inhibits[] = { APICV_INHIBIT_REASONS };
+
+ BUILD_BUG_ON(ARRAY_SIZE(apicv_inhibits) != NR_APICV_INHIBIT_REASONS);
+
if (set)
__set_bit(reason, inhibits);
else
--
2.39.3
