[PATCH v2 10/12] viridian: log initial invocation of each type of hypercall

[Paul Durrant <paul@xen.org>]

From: Paul Durrant <pdurrant@amazon.com>

To make is simpler to observe which viridian hypercalls are issued by a
particular Windows guest, this patch adds a per-domain mask to track them.
Each type of hypercall causes a different bit to be set in the mask and
when the bit transitions from clear to set, a log line is emitted showing
the name of the hypercall and the domain that issued it.

Signed-off-by: Paul Durrant <pdurrant@amazon.com>
---
Cc: Wei Liu <wl@xen.org>
Cc: Jan Beulich <jbeulich@suse.com>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>
Cc: "Roger Pau Monné" <roger.pau@citrix.com>

v2:
 - Use DECLARE_BITMAP() for 'hypercall_flags'
 - Use an enum for _HCALL_* values
---
 xen/arch/x86/hvm/viridian/viridian.c | 21 +++++++++++++++++++++
 xen/include/asm-x86/hvm/viridian.h   | 10 ++++++++++
 2 files changed, 31 insertions(+)

diff --git a/xen/arch/x86/hvm/viridian/viridian.c b/xen/arch/x86/hvm/viridian/viridian.c
index 74227fecbcd4..de3f5f86777c 100644
--- a/xen/arch/x86/hvm/viridian/viridian.c
+++ b/xen/arch/x86/hvm/viridian/viridian.c
@@ -933,6 +933,7 @@ int viridian_hypercall(struct cpu_user_regs *regs)
 {
     struct vcpu *curr = current;
     struct domain *currd = curr->domain;
+    struct viridian_domain *vd = currd->arch.hvm.viridian;
     int mode = hvm_guest_x86_mode(curr);
     unsigned long input_params_gpa, output_params_gpa;
     int rc = 0;
@@ -962,6 +963,10 @@ int viridian_hypercall(struct cpu_user_regs *regs)
     switch ( input.call_code )
     {
     case HVCALL_NOTIFY_LONG_SPIN_WAIT:
+        if ( !test_and_set_bit(_HCALL_spin_wait, vd->hypercall_flags) )
+            printk(XENLOG_G_INFO "d%d: VIRIDIAN HVCALL_NOTIFY_LONG_SPIN_WAIT\n",
+                   currd->domain_id);
+
         /*
          * See section 14.5.1 of the specification.
          */
@@ -970,22 +975,38 @@ int viridian_hypercall(struct cpu_user_regs *regs)
 
     case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE:
     case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST:
+        if ( !test_and_set_bit(_HCALL_flush, vd->hypercall_flags) )
+            printk(XENLOG_G_INFO "%pd: VIRIDIAN HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE/LIST\n",
+                   currd);
+
         rc = hvcall_flush(&input, &output, input_params_gpa,
                           output_params_gpa);
         break;
 
     case HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE_EX:
     case HVCALL_FLUSH_VIRTUAL_ADDRESS_LIST_EX:
+        if ( !test_and_set_bit(_HCALL_flush_ex, vd->hypercall_flags) )
+            printk(XENLOG_G_INFO "%pd: VIRIDIAN HVCALL_FLUSH_VIRTUAL_ADDRESS_SPACE/LIST_EX\n",
+                   currd);
+
         rc = hvcall_flush_ex(&input, &output, input_params_gpa,
                              output_params_gpa);
         break;
 
     case HVCALL_SEND_IPI:
+        if ( !test_and_set_bit(_HCALL_ipi, vd->hypercall_flags) )
+            printk(XENLOG_G_INFO "%pd: VIRIDIAN HVCALL_SEND_IPI\n",
+                   currd);
+
         rc = hvcall_ipi(&input, &output, input_params_gpa,
                         output_params_gpa);
         break;
 
     case HVCALL_SEND_IPI_EX:
+        if ( !test_and_set_bit(_HCALL_ipi_ex, vd->hypercall_flags) )
+            printk(XENLOG_G_INFO "%pd: VIRIDIAN HVCALL_SEND_IPI_EX\n",
+                   currd);
+
         rc = hvcall_ipi_ex(&input, &output, input_params_gpa,
                            output_params_gpa);
         break;
diff --git a/xen/include/asm-x86/hvm/viridian.h b/xen/include/asm-x86/hvm/viridian.h
index cbf77d9c760b..4c8ff6e80b6f 100644
--- a/xen/include/asm-x86/hvm/viridian.h
+++ b/xen/include/asm-x86/hvm/viridian.h
@@ -55,10 +55,20 @@ struct viridian_time_ref_count
     int64_t off;
 };
 
+enum {
+    _HCALL_spin_wait,
+    _HCALL_flush,
+    _HCALL_flush_ex,
+    _HCALL_ipi,
+    _HCALL_ipi_ex,
+    _HCALL_nr /* must be last */
+};
+
 struct viridian_domain
 {
     union hv_guest_os_id guest_os_id;
     union hv_vp_assist_page_msr hypercall_gpa;
+    DECLARE_BITMAP(hypercall_flags, _HCALL_nr);
     struct viridian_time_ref_count time_ref_count;
     struct viridian_page reference_tsc;
 };
-- 
2.20.1