Commit 6ab0b9fe authored by Rik van Riel's avatar Rik van Riel Committed by Radim Krčmář
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x86,kvm: remove KVM emulator get_fpu / put_fpu 



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: default avatarRik van Riel <riel@redhat.com>
Suggested-by: default avatarDavid Hildenbrand <david@redhat.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent f775b13e

arch/x86/include/asm/kvm_emulate.h

+0 −2
Original line number Diff line number Diff line
@@ -214,8 +214,6 @@ struct x86_emulate_ops { 
	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);

arch/x86/kvm/emulate.c

+0 −24
Original line number Diff line number Diff line
@@ -1046,7 +1046,6 @@ static void fetch_register_operand(struct operand *op) 


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;
@@ -1068,13 +1067,11 @@ static void read_sse_reg(struct x86_emulate_ctxt *ctxt, sse128_t *data, int reg) 
#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;
@@ -1096,12 +1093,10 @@ static void write_sse_reg(struct x86_emulate_ctxt *ctxt, sse128_t *data, 
#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;
@@ -1113,12 +1108,10 @@ static void read_mmx_reg(struct x86_emulate_ctxt *ctxt, u64 *data, int reg) 
	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;
@@ -1130,7 +1123,6 @@ static void write_mmx_reg(struct x86_emulate_ctxt *ctxt, u64 *data, int reg) 
	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)
@@ -1138,9 +1130,7 @@ static int em_fninit(struct x86_emulate_ctxt *ctxt) 
	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;

}
@@ -1151,9 +1141,7 @@ static int em_fnstcw(struct x86_emulate_ctxt *ctxt) 
	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;
@@ -1167,9 +1155,7 @@ static int em_fnstsw(struct x86_emulate_ctxt *ctxt) 
	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;
@@ -4001,12 +3987,8 @@ static int em_fxsave(struct x86_emulate_ctxt *ctxt) 
	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;
@@ -4049,8 +4031,6 @@ static int em_fxrstor(struct x86_emulate_ctxt *ctxt) 
	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)
@@ -4066,8 +4046,6 @@ static int em_fxrstor(struct x86_emulate_ctxt *ctxt) 
		rc = asm_safe("fxrstor %[fx]", : [fx] "m"(fx_state));



out:

	ctxt->ops->put_fpu(ctxt);



	return rc;

}
@@ -5317,9 +5295,7 @@ static int flush_pending_x87_faults(struct x86_emulate_ctxt *ctxt) 
{

	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);

arch/x86/kvm/x86.c

+0 −10
Original line number Diff line number Diff line
@@ -5251,14 +5251,6 @@ static void emulator_halt(struct x86_emulate_ctxt *ctxt) 
	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 @@ static const struct x86_emulate_ops emulate_ops = { 
	.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,

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