xen/x86: cleanup unused NMI/MCE code

pv_raise_interrupt() is only called for NMIs these days, so the MCE
specific part can be removed. Rename pv_raise_interrupt() to
pv_raise_nmi() and NMI_MCE_SOFTIRQ to NMI_SOFTIRQ.

Additionally there is no need to pin the vcpu which the NMI is delivered
to; that is a leftover of (already removed) MCE handling. So remove the
pinning, too. Note that pinning was introduced by commit 355b0469a8
adding MCE support (with NMI support existing already). MCE using that
pinning was removed with commit 3a91769d6e again without cleaning up the
code.

Signed-off-by: Juergen Gross <jgross@suse.com>
Reviewed-and-tested-by: Andrew Cooper <andrew.cooper3@citrix.com>

diff --git a/xen/arch/x86/pv/traps.c b/xen/arch/x86/pv/traps.c
index 1740784ff21864af8fc421c63b443c1596cd6e0c..aa26e7171a43ce0faf7ac30d7e827de0f427fe51 100644 (file)
--- a/xen/arch/x86/pv/traps.c
+++ b/xen/arch/x86/pv/traps.c
@@ -136,47 +136,20 @@ bool set_guest_nmi_trapbounce(void)
     return !null_trap_bounce(curr, tb);
 }
 
-struct softirq_trap {
-    struct domain *domain;   /* domain to inject trap */
-    struct vcpu *vcpu;       /* vcpu to inject trap */
-    unsigned int processor;  /* physical cpu to inject trap */
-};
+static DEFINE_PER_CPU(struct vcpu *, softirq_nmi_vcpu);
 
-static DEFINE_PER_CPU(struct softirq_trap, softirq_trap);
-
-static void nmi_mce_softirq(void)
+static void nmi_softirq(void)
 {
-    unsigned int cpu = smp_processor_id();
-    struct softirq_trap *st = &per_cpu(softirq_trap, cpu);
+    struct vcpu **v_ptr = &this_cpu(softirq_nmi_vcpu);
 
-    BUG_ON(st->vcpu == NULL);
+    BUG_ON(*v_ptr == NULL);
 
     /*
-     * Set the tmp value unconditionally, so that the check in the iret
-     * hypercall works.
-     */
-    cpumask_copy(st->vcpu->cpu_hard_affinity_tmp,
-                 st->vcpu->cpu_hard_affinity);
-
-    if ( (cpu != st->processor) ||
-         (st->processor != st->vcpu->processor) )
-    {
-
-        /*
-         * We are on a different physical cpu.  Make sure to wakeup the vcpu on
-         * the specified processor.
-         */
-        vcpu_set_hard_affinity(st->vcpu, cpumask_of(st->processor));
-
-        /* Affinity is restored in the iret hypercall. */
-    }
-
-    /*
-     * Only used to defer wakeup of domain/vcpu to a safe (non-NMI/MCE)
+     * Only used to defer wakeup of domain/vcpu to a safe (non-NMI)
      * context.
      */
-    vcpu_kick(st->vcpu);
-    st->vcpu = NULL;
+    vcpu_kick(*v_ptr);
+    *v_ptr = NULL;
 }
 
 void __init pv_trap_init(void)
@@ -189,50 +162,26 @@ void __init pv_trap_init(void)
     _set_gate(idt_table + LEGACY_SYSCALL_VECTOR, SYS_DESC_trap_gate, 3,
               &int80_direct_trap);
 
-    open_softirq(NMI_MCE_SOFTIRQ, nmi_mce_softirq);
+    open_softirq(NMI_SOFTIRQ, nmi_softirq);
 }
 
-int pv_raise_interrupt(struct vcpu *v, uint8_t vector)
+/*
+ * Deliver NMI to PV guest. Return 0 on success.
+ * Called in NMI context, so no use of printk().
+ */
+int pv_raise_nmi(struct vcpu *v)
 {
-    struct softirq_trap *st = &per_cpu(softirq_trap, smp_processor_id());
+    struct vcpu **v_ptr = &per_cpu(softirq_nmi_vcpu, smp_processor_id());
 
-    switch ( vector )
+    if ( cmpxchgptr(v_ptr, NULL, v) )
+        return -EBUSY;
+    if ( !test_and_set_bool(v->nmi_pending) )
     {
-    case TRAP_nmi:
-        if ( cmpxchgptr(&st->vcpu, NULL, v) )
-            return -EBUSY;
-        if ( !test_and_set_bool(v->nmi_pending) )
-        {
-            st->domain = v->domain;
-            st->processor = v->processor;
-
-            /* Not safe to wake up a vcpu here */
-            raise_softirq(NMI_MCE_SOFTIRQ);
-            return 0;
-        }
-        st->vcpu = NULL;
-        break;
-
-    case TRAP_machine_check:
-        if ( cmpxchgptr(&st->vcpu, NULL, v) )
-            return -EBUSY;
-
-        /*
-         * We are called by the machine check (exception or polling) handlers
-         * on the physical CPU that reported a machine check error.
-         */
-        if ( !test_and_set_bool(v->mce_pending) )
-        {
-            st->domain = v->domain;
-            st->processor = v->processor;
-
-            /* not safe to wake up a vcpu here */
-            raise_softirq(NMI_MCE_SOFTIRQ);
-            return 0;
-        }
-        st->vcpu = NULL;
-        break;
+        /* Not safe to wake up a vcpu here */
+        raise_softirq(NMI_SOFTIRQ);
+        return 0;
     }
+    *v_ptr = NULL;
 
     /* Delivery failed */
     return -EIO;

diff --git a/xen/arch/x86/traps.c b/xen/arch/x86/traps.c
index 25b4b47e5e557f085cd104b48676281cd31ed4e6..08d7edc568ef80e887563a6959b4f367316388ef 100644 (file)
--- a/xen/arch/x86/traps.c
+++ b/xen/arch/x86/traps.c
@@ -1600,14 +1600,6 @@ void async_exception_cleanup(struct vcpu *curr)
     if ( !curr->async_exception_mask )
         return;
 
-    /* Restore affinity.  */
-    if ( !cpumask_empty(curr->cpu_hard_affinity_tmp) &&
-         !cpumask_equal(curr->cpu_hard_affinity_tmp, curr->cpu_hard_affinity) )
-    {
-        vcpu_set_hard_affinity(curr, curr->cpu_hard_affinity_tmp);
-        cpumask_clear(curr->cpu_hard_affinity_tmp);
-    }
-
     if ( !(curr->async_exception_mask & (curr->async_exception_mask - 1)) )
         trap = __scanbit(curr->async_exception_mask, VCPU_TRAP_NONE);
     else
@@ -1634,7 +1626,7 @@ static void nmi_hwdom_report(unsigned int reason_idx)
 
     set_bit(reason_idx, nmi_reason(d));
 
-    pv_raise_interrupt(d->vcpu[0], TRAP_nmi);
+    pv_raise_nmi(d->vcpu[0]);
 }
 
 static void pci_serr_error(const struct cpu_user_regs *regs)

diff --git a/xen/common/domain.c b/xen/common/domain.c
index 55aa759b7551c24feb64b7d3fc2f76684afd4749..bc56a51815a33f5c8ab5cd0176693b50d370e8ee 100644 (file)
--- a/xen/common/domain.c
+++ b/xen/common/domain.c
@@ -133,7 +133,6 @@ static void vcpu_info_reset(struct vcpu *v)
 static void vcpu_destroy(struct vcpu *v)
 {
     free_cpumask_var(v->cpu_hard_affinity);
-    free_cpumask_var(v->cpu_hard_affinity_tmp);
     free_cpumask_var(v->cpu_hard_affinity_saved);
     free_cpumask_var(v->cpu_soft_affinity);
 
@@ -161,7 +160,6 @@ struct vcpu *vcpu_create(
     grant_table_init_vcpu(v);
 
     if ( !zalloc_cpumask_var(&v->cpu_hard_affinity) ||
-         !zalloc_cpumask_var(&v->cpu_hard_affinity_tmp) ||
          !zalloc_cpumask_var(&v->cpu_hard_affinity_saved) ||
          !zalloc_cpumask_var(&v->cpu_soft_affinity) )
         goto fail;
@@ -1269,7 +1267,6 @@ int vcpu_reset(struct vcpu *v)
     v->async_exception_mask = 0;
     memset(v->async_exception_state, 0, sizeof(v->async_exception_state));
 #endif
-    cpumask_clear(v->cpu_hard_affinity_tmp);
     clear_bit(_VPF_blocked, &v->pause_flags);
     clear_bit(_VPF_in_reset, &v->pause_flags);
 

diff --git a/xen/include/asm-x86/pv/traps.h b/xen/include/asm-x86/pv/traps.h
index fcc75f5e9af32ca6cd49618a17cdd07bc96e8401..855203c4e288bd7f1dd12d62dbfcb5379e5b69ca 100644 (file)
--- a/xen/include/asm-x86/pv/traps.h
+++ b/xen/include/asm-x86/pv/traps.h
@@ -27,8 +27,7 @@
 
 void pv_trap_init(void);
 
-/* Deliver interrupt to PV guest. Return 0 on success. */
-int pv_raise_interrupt(struct vcpu *v, uint8_t vector);
+int pv_raise_nmi(struct vcpu *v);
 
 int pv_emulate_privileged_op(struct cpu_user_regs *regs);
 void pv_emulate_gate_op(struct cpu_user_regs *regs);
@@ -46,8 +45,7 @@ static inline bool pv_trap_callback_registered(const struct vcpu *v,
 
 static inline void pv_trap_init(void) {}
 
-/* Deliver interrupt to PV guest. Return 0 on success. */
-static inline int pv_raise_interrupt(struct vcpu *v, uint8_t vector) { return -EOPNOTSUPP; }
+static inline int pv_raise_nmi(struct vcpu *v) { return -EOPNOTSUPP; }
 
 static inline int pv_emulate_privileged_op(struct cpu_user_regs *regs) { return 0; }
 static inline void pv_emulate_gate_op(struct cpu_user_regs *regs) {}

diff --git a/xen/include/asm-x86/softirq.h b/xen/include/asm-x86/softirq.h
index 5c1a7db566b567d4144947ce4912ad1b1d4a4212..0b7a77f11f69e256e7a9a1570b8b12f3a1112583 100644 (file)
--- a/xen/include/asm-x86/softirq.h
+++ b/xen/include/asm-x86/softirq.h
@@ -1,7 +1,7 @@
 #ifndef __ASM_SOFTIRQ_H__
 #define __ASM_SOFTIRQ_H__
 
-#define NMI_MCE_SOFTIRQ        (NR_COMMON_SOFTIRQS + 0)
+#define NMI_SOFTIRQ            (NR_COMMON_SOFTIRQS + 0)
 #define TIME_CALIBRATE_SOFTIRQ (NR_COMMON_SOFTIRQS + 1)
 #define VCPU_KICK_SOFTIRQ      (NR_COMMON_SOFTIRQS + 2)
 

diff --git a/xen/include/xen/sched.h b/xen/include/xen/sched.h
index b40c8fd138734d128d785cf9ddede9f15013afba..c197e93d735ec1fe3e0e0e3e590b6b546e40414e 100644 (file)
--- a/xen/include/xen/sched.h
+++ b/xen/include/xen/sched.h
@@ -245,8 +245,6 @@ struct vcpu
 
     /* Bitmask of CPUs on which this VCPU may run. */
     cpumask_var_t    cpu_hard_affinity;
-    /* Used to change affinity temporarily. */
-    cpumask_var_t    cpu_hard_affinity_tmp;
     /* Used to restore affinity across S3. */
     cpumask_var_t    cpu_hard_affinity_saved;