[PATCH] KVM: Clean up AMD SVM debug registers load and unload

By letting gcc choose the temporary register for us, we lose arch dependency
and some ugliness.  Conceivably gcc will also generate marginally better code.

Signed-off-by: Avi Kivity <avi@qumranet.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Avi Kivity 2006-12-13 00:33:45 -08:00 committed by Linus Torvalds
parent fd24dc4af6
commit 5aff458e9c

View File

@ -1345,53 +1345,18 @@ static void kvm_reput_irq(struct kvm_vcpu *vcpu)
static void save_db_regs(unsigned long *db_regs)
{
#ifdef __x86_64__
asm ("mov %%dr0, %%rax \n\t"
"mov %%rax, %[dr0] \n\t"
"mov %%dr1, %%rax \n\t"
"mov %%rax, %[dr1] \n\t"
"mov %%dr2, %%rax \n\t"
"mov %%rax, %[dr2] \n\t"
"mov %%dr3, %%rax \n\t"
"mov %%rax, %[dr3] \n\t"
: [dr0] "=m"(db_regs[0]),
[dr1] "=m"(db_regs[1]),
[dr2] "=m"(db_regs[2]),
[dr3] "=m"(db_regs[3])
: : "rax");
#else
asm ("mov %%dr0, %%eax \n\t"
"mov %%eax, %[dr0] \n\t"
"mov %%dr1, %%eax \n\t"
"mov %%eax, %[dr1] \n\t"
"mov %%dr2, %%eax \n\t"
"mov %%eax, %[dr2] \n\t"
"mov %%dr3, %%eax \n\t"
"mov %%eax, %[dr3] \n\t"
: [dr0] "=m"(db_regs[0]),
[dr1] "=m"(db_regs[1]),
[dr2] "=m"(db_regs[2]),
[dr3] "=m"(db_regs[3])
: : "eax");
#endif
asm volatile ("mov %%dr0, %0" : "=r"(db_regs[0]));
asm volatile ("mov %%dr1, %0" : "=r"(db_regs[1]));
asm volatile ("mov %%dr2, %0" : "=r"(db_regs[2]));
asm volatile ("mov %%dr3, %0" : "=r"(db_regs[3]));
}
static void load_db_regs(unsigned long *db_regs)
{
asm volatile ("mov %[dr0], %%dr0 \n\t"
"mov %[dr1], %%dr1 \n\t"
"mov %[dr2], %%dr2 \n\t"
"mov %[dr3], %%dr3 \n\t"
:
: [dr0] "r"(db_regs[0]),
[dr1] "r"(db_regs[1]),
[dr2] "r"(db_regs[2]),
[dr3] "r"(db_regs[3])
#ifdef __x86_64__
: "rax");
#else
: "eax");
#endif
asm volatile ("mov %0, %%dr0" : : "r"(db_regs[0]));
asm volatile ("mov %0, %%dr1" : : "r"(db_regs[1]));
asm volatile ("mov %0, %%dr2" : : "r"(db_regs[2]));
asm volatile ("mov %0, %%dr3" : : "r"(db_regs[3]));
}
static int svm_vcpu_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)