From: Rik van Riel <riel@redhat.com>
Date: Tue, 14 Nov 2017 16:54:24 -0500
Subject: x86,kvm: remove KVM emulator get_fpu / put_fpu
Patch-mainline: v4.15-rc3
Git-commit: 6ab0b9feb82a7ac09956e6761fec73cd47789df5
References: bsc#1077761
Now that get_fpu and put_fpu do nothing, because the scheduler will
automatically load and restore the guest FPU context for us while we
are in this code (deep inside the vcpu_run main loop), we can get rid
of the get_fpu and put_fpu hooks.
Signed-off-by: Rik van Riel <riel@redhat.com>
Suggested-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Acked-by: Alexander Graf <agraf@suse.de>
---
arch/x86/include/asm/kvm_emulate.h | 2 --
arch/x86/kvm/emulate.c | 24 ------------------------
arch/x86/kvm/x86.c | 10 ----------
3 files changed, 36 deletions(-)
--- a/arch/x86/include/asm/kvm_emulate.h
+++ b/arch/x86/include/asm/kvm_emulate.h
@@ -213,8 +213,6 @@
void (*halt)(struct x86_emulate_ctxt *ctxt);
void (*wbinvd)(struct x86_emulate_ctxt *ctxt);
int (*fix_hypercall)(struct x86_emulate_ctxt *ctxt);
- void (*get_fpu)(struct x86_emulate_ctxt *ctxt); /* disables preempt */
- void (*put_fpu)(struct x86_emulate_ctxt *ctxt); /* reenables preempt */
int (*intercept)(struct x86_emulate_ctxt *ctxt,
struct x86_instruction_info *info,
enum x86_intercept_stage stage);
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -1044,7 +1044,6 @@
static void read_sse_reg(struct x86_emulate_ctxt *ctxt, sse128_t *data, int reg)
{
- ctxt->ops->get_fpu(ctxt);
switch (reg) {
case 0: asm("movdqa %%xmm0, %0" : "=m"(*data)); break;
case 1: asm("movdqa %%xmm1, %0" : "=m"(*data)); break;
@@ -1066,13 +1065,11 @@
#endif
default: BUG();
}
- ctxt->ops->put_fpu(ctxt);
}
static void write_sse_reg(struct x86_emulate_ctxt *ctxt, sse128_t *data,
int reg)
{
- ctxt->ops->get_fpu(ctxt);
switch (reg) {
case 0: asm("movdqa %0, %%xmm0" : : "m"(*data)); break;
case 1: asm("movdqa %0, %%xmm1" : : "m"(*data)); break;
@@ -1094,12 +1091,10 @@
#endif
default: BUG();
}
- ctxt->ops->put_fpu(ctxt);
}
static void read_mmx_reg(struct x86_emulate_ctxt *ctxt, u64 *data, int reg)
{
- ctxt->ops->get_fpu(ctxt);
switch (reg) {
case 0: asm("movq %%mm0, %0" : "=m"(*data)); break;
case 1: asm("movq %%mm1, %0" : "=m"(*data)); break;
@@ -1111,12 +1106,10 @@
case 7: asm("movq %%mm7, %0" : "=m"(*data)); break;
default: BUG();
}
- ctxt->ops->put_fpu(ctxt);
}
static void write_mmx_reg(struct x86_emulate_ctxt *ctxt, u64 *data, int reg)
{
- ctxt->ops->get_fpu(ctxt);
switch (reg) {
case 0: asm("movq %0, %%mm0" : : "m"(*data)); break;
case 1: asm("movq %0, %%mm1" : : "m"(*data)); break;
@@ -1128,7 +1121,6 @@
case 7: asm("movq %0, %%mm7" : : "m"(*data)); break;
default: BUG();
}
- ctxt->ops->put_fpu(ctxt);
}
static int em_fninit(struct x86_emulate_ctxt *ctxt)
@@ -1136,9 +1128,7 @@
if (ctxt->ops->get_cr(ctxt, 0) & (X86_CR0_TS | X86_CR0_EM))
return emulate_nm(ctxt);
- ctxt->ops->get_fpu(ctxt);
asm volatile("fninit");
- ctxt->ops->put_fpu(ctxt);
return X86EMUL_CONTINUE;
}
@@ -1149,9 +1139,7 @@
if (ctxt->ops->get_cr(ctxt, 0) & (X86_CR0_TS | X86_CR0_EM))
return emulate_nm(ctxt);
- ctxt->ops->get_fpu(ctxt);
asm volatile("fnstcw %0": "+m"(fcw));
- ctxt->ops->put_fpu(ctxt);
ctxt->dst.val = fcw;
@@ -1165,9 +1153,7 @@
if (ctxt->ops->get_cr(ctxt, 0) & (X86_CR0_TS | X86_CR0_EM))
return emulate_nm(ctxt);
- ctxt->ops->get_fpu(ctxt);
asm volatile("fnstsw %0": "+m"(fsw));
- ctxt->ops->put_fpu(ctxt);
ctxt->dst.val = fsw;
@@ -3999,12 +3985,8 @@
if (rc != X86EMUL_CONTINUE)
return rc;
- ctxt->ops->get_fpu(ctxt);
-
rc = asm_safe("fxsave %[fx]", , [fx] "+m"(fx_state));
- ctxt->ops->put_fpu(ctxt);
-
if (rc != X86EMUL_CONTINUE)
return rc;
@@ -4047,8 +4029,6 @@
if (rc != X86EMUL_CONTINUE)
return rc;
- ctxt->ops->get_fpu(ctxt);
-
if (size < __fxstate_size(16)) {
rc = fxregs_fixup(&fx_state, size);
if (rc != X86EMUL_CONTINUE)
@@ -4064,8 +4044,6 @@
rc = asm_safe("fxrstor %[fx]", : [fx] "m"(fx_state));
out:
- ctxt->ops->put_fpu(ctxt);
-
return rc;
}
@@ -5315,9 +5293,7 @@
{
int rc;
- ctxt->ops->get_fpu(ctxt);
rc = asm_safe("fwait");
- ctxt->ops->put_fpu(ctxt);
if (unlikely(rc != X86EMUL_CONTINUE))
return emulate_exception(ctxt, MF_VECTOR, 0, false);
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -5251,14 +5251,6 @@
emul_to_vcpu(ctxt)->arch.halt_request = 1;
}
-static void emulator_get_fpu(struct x86_emulate_ctxt *ctxt)
-{
-}
-
-static void emulator_put_fpu(struct x86_emulate_ctxt *ctxt)
-{
-}
-
static int emulator_intercept(struct x86_emulate_ctxt *ctxt,
struct x86_instruction_info *info,
enum x86_intercept_stage stage)
@@ -5336,8 +5328,6 @@
.halt = emulator_halt,
.wbinvd = emulator_wbinvd,
.fix_hypercall = emulator_fix_hypercall,
- .get_fpu = emulator_get_fpu,
- .put_fpu = emulator_put_fpu,
.intercept = emulator_intercept,
.get_cpuid = emulator_get_cpuid,
.set_nmi_mask = emulator_set_nmi_mask,