x86/kvm: Use generic xfer to guest work function

Use the generic infrastructure to check for and handle pending work before
transitioning into guest mode.

This now handles TIF_NOTIFY_RESUME as well which was ignored so
far. Handling it is important as this covers task work and task work will
be used to offload the heavy lifting of POSIX CPU timers to thread context.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200722220520.979724969@linutronix.de

diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig
index b277a2db62676437aeb2140d30ffaf919aec81ac..fbd5bd7a945afdaf809508d0785e1dbd8af58050 100644 (file)
--- a/arch/x86/kvm/Kconfig
+++ b/arch/x86/kvm/Kconfig
@@ -42,6 +42,7 @@ config KVM
        select HAVE_KVM_MSI
        select HAVE_KVM_CPU_RELAX_INTERCEPT
        select HAVE_KVM_NO_POLL
+       select KVM_XFER_TO_GUEST_WORK
        select KVM_GENERIC_DIRTYLOG_READ_PROTECT
        select KVM_VFIO
        select SRCU

diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 13745f2a5ecdf53ebd72560ceac358cc87dd7bf5..9909375ee1fdfa03453562ccf85dbe5f3745240d 100644 (file)
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -27,6 +27,7 @@
 #include <linux/slab.h>
 #include <linux/tboot.h>
 #include <linux/trace_events.h>
+#include <linux/entry-kvm.h>
 
 #include <asm/apic.h>
 #include <asm/asm.h>
@@ -5373,14 +5374,12 @@ static int handle_invalid_guest_state(struct kvm_vcpu *vcpu)
                }
 
                /*
-                * Note, return 1 and not 0, vcpu_run() is responsible for
-                * morphing the pending signal into the proper return code.
+                * Note, return 1 and not 0, vcpu_run() will invoke
+                * xfer_to_guest_mode() which will create a proper return
+                * code.
                 */
-               if (signal_pending(current))
+               if (__xfer_to_guest_mode_work_pending())
                        return 1;
-
-               if (need_resched())
-                       schedule();
        }
 
        return 1;

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 88c593f83b28501a036310521eb14291eed59bed..82d4a9e889083c7671c697c4819b72d6ac41a5c9 100644 (file)
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -56,6 +56,7 @@
 #include <linux/sched/stat.h>
 #include <linux/sched/isolation.h>
 #include <linux/mem_encrypt.h>
+#include <linux/entry-kvm.h>
 
 #include <trace/events/kvm.h>
 
@@ -1587,7 +1588,7 @@ EXPORT_SYMBOL_GPL(kvm_emulate_wrmsr);
 bool kvm_vcpu_exit_request(struct kvm_vcpu *vcpu)
 {
        return vcpu->mode == EXITING_GUEST_MODE || kvm_request_pending(vcpu) ||
-               need_resched() || signal_pending(current);
+               xfer_to_guest_mode_work_pending();
 }
 EXPORT_SYMBOL_GPL(kvm_vcpu_exit_request);
 
@@ -8681,15 +8682,11 @@ static int vcpu_run(struct kvm_vcpu *vcpu)
                        break;
                }
 
-               if (signal_pending(current)) {
-                       r = -EINTR;
-                       vcpu->run->exit_reason = KVM_EXIT_INTR;
-                       ++vcpu->stat.signal_exits;
-                       break;
-               }
-               if (need_resched()) {
+               if (xfer_to_guest_mode_work_pending()) {
                        srcu_read_unlock(&kvm->srcu, vcpu->srcu_idx);
-                       cond_resched();
+                       r = xfer_to_guest_mode_handle_work(vcpu);
+                       if (r)
+                               return r;
                        vcpu->srcu_idx = srcu_read_lock(&kvm->srcu);
                }
        }