[Qemu-devel] [PATCH 13/35] hvf: access cpu->interrupt_request with atomics

[Emilio G. Cota]

I am not familiar with hvf, so I opted for the safe
(and slow) route of performing probably many unnecessary
atomic_reads.

Cc: Richard Henderson <address@hidden>
Cc: Eduardo Habkost <address@hidden>
Signed-off-by: Emilio G. Cota <address@hidden>
---
 target/i386/hvf/hvf.c    |  7 ++++---
 target/i386/hvf/x86hvf.c | 22 +++++++++++-----------
 2 files changed, 15 insertions(+), 14 deletions(-)

diff --git a/target/i386/hvf/hvf.c b/target/i386/hvf/hvf.c
index df69e6d0a7..9c49d3c318 100644
--- a/target/i386/hvf/hvf.c
+++ b/target/i386/hvf/hvf.c
@@ -251,7 +251,7 @@ void update_apic_tpr(CPUState *cpu)
 
 static void hvf_handle_interrupt(CPUState * cpu, int mask)
 {
-    cpu->interrupt_request |= mask;
+    atomic_or(&cpu->interrupt_request, mask);
     if (!qemu_cpu_is_self(cpu)) {
         qemu_cpu_kick(cpu);
     }
@@ -713,10 +713,11 @@ int hvf_vcpu_exec(CPUState *cpu)
         ret = 0;
         switch (exit_reason) {
         case EXIT_REASON_HLT: {
+            int interrupt_request = atomic_read(&cpu->interrupt_request);
             macvm_set_rip(cpu, rip + ins_len);
-            if (!((cpu->interrupt_request & CPU_INTERRUPT_HARD) &&
+            if (!((interrupt_request & CPU_INTERRUPT_HARD) &&
                 (EFLAGS(env) & IF_MASK))
-                && !(cpu->interrupt_request & CPU_INTERRUPT_NMI) &&
+                && !(interrupt_request & CPU_INTERRUPT_NMI) &&
                 !(idtvec_info & VMCS_IDT_VEC_VALID)) {
                 cpu->halted = 1;
                 ret = EXCP_HLT;
diff --git a/target/i386/hvf/x86hvf.c b/target/i386/hvf/x86hvf.c
index 3ac796b885..878714b99c 100644
--- a/target/i386/hvf/x86hvf.c
+++ b/target/i386/hvf/x86hvf.c
@@ -400,7 +400,7 @@ bool hvf_inject_interrupts(CPUState *cpu_state)
         };
     }
 
-    if (cpu_state->interrupt_request & CPU_INTERRUPT_NMI) {
+    if (atomic_read(&cpu_state->interrupt_request) & CPU_INTERRUPT_NMI) {
         if (!(env->hflags2 & HF2_NMI_MASK) && !(info & VMCS_INTR_VALID)) {
             cpu_reset_interrupt(cpu_state, CPU_INTERRUPT_NMI);
             info = VMCS_INTR_VALID | VMCS_INTR_T_NMI | NMI_VEC;
@@ -411,7 +411,7 @@ bool hvf_inject_interrupts(CPUState *cpu_state)
     }
 
     if (!(env->hflags & HF_INHIBIT_IRQ_MASK) &&
-        (cpu_state->interrupt_request & CPU_INTERRUPT_HARD) &&
+        (atomic_read(&cpu_state->interrupt_request) & CPU_INTERRUPT_HARD) &&
         (EFLAGS(env) & IF_MASK) && !(info & VMCS_INTR_VALID)) {
         int line = cpu_get_pic_interrupt(&x86cpu->env);
         cpu_reset_interrupt(cpu_state, CPU_INTERRUPT_HARD);
@@ -420,11 +420,11 @@ bool hvf_inject_interrupts(CPUState *cpu_state)
                   VMCS_INTR_VALID | VMCS_INTR_T_HWINTR);
         }
     }
-    if (cpu_state->interrupt_request & CPU_INTERRUPT_HARD) {
+    if (atomic_read(&cpu_state->interrupt_request) & CPU_INTERRUPT_HARD) {
         vmx_set_int_window_exiting(cpu_state);
     }
-    return (cpu_state->interrupt_request
-            & (CPU_INTERRUPT_INIT | CPU_INTERRUPT_TPR));
+    return atomic_read(&cpu_state->interrupt_request)
+           & (CPU_INTERRUPT_INIT | CPU_INTERRUPT_TPR);
 }
 
 int hvf_process_events(CPUState *cpu_state)
@@ -434,25 +434,25 @@ int hvf_process_events(CPUState *cpu_state)
 
     EFLAGS(env) = rreg(cpu_state->hvf_fd, HV_X86_RFLAGS);
 
-    if (cpu_state->interrupt_request & CPU_INTERRUPT_INIT) {
+    if (atomic_read(&cpu_state->interrupt_request) & CPU_INTERRUPT_INIT) {
         hvf_cpu_synchronize_state(cpu_state);
         do_cpu_init(cpu);
     }
 
-    if (cpu_state->interrupt_request & CPU_INTERRUPT_POLL) {
+    if (atomic_read(&cpu_state->interrupt_request) & CPU_INTERRUPT_POLL) {
         cpu_reset_interrupt(cpu_state, CPU_INTERRUPT_POLL);
         apic_poll_irq(cpu->apic_state);
     }
-    if (((cpu_state->interrupt_request & CPU_INTERRUPT_HARD) &&
+    if (((atomic_read(&cpu_state->interrupt_request) & CPU_INTERRUPT_HARD) &&
         (EFLAGS(env) & IF_MASK)) ||
-        (cpu_state->interrupt_request & CPU_INTERRUPT_NMI)) {
+        (atomic_read(&cpu_state->interrupt_request) & CPU_INTERRUPT_NMI)) {
         cpu_state->halted = 0;
     }
-    if (cpu_state->interrupt_request & CPU_INTERRUPT_SIPI) {
+    if (atomic_read(&cpu_state->interrupt_request) & CPU_INTERRUPT_SIPI) {
         hvf_cpu_synchronize_state(cpu_state);
         do_cpu_sipi(cpu);
     }
-    if (cpu_state->interrupt_request & CPU_INTERRUPT_TPR) {
+    if (atomic_read(&cpu_state->interrupt_request) & CPU_INTERRUPT_TPR) {
         cpu_reset_interrupt(cpu_state, CPU_INTERRUPT_TPR);
         hvf_cpu_synchronize_state(cpu_state);
         apic_handle_tpr_access_report(cpu->apic_state, env->eip,
-- 
2.17.1