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| author | Ingo Molnar | 2015-04-23 12:49:20 +0200 |
|---|---|---|
| committer | Ingo Molnar | 2015-05-19 15:47:25 +0200 |
| commit | c5bedc6847c3be6efe0e671a6155c9a25fd468bf (patch) | |
| tree | f1eb66ea2807447c95e915f281d6815578b7e627 /arch/x86/kvm/x86.c | |
| parent | x86/fpu: Document fpu__unlazy_stopped() (diff) | |
| download | kernel-qcow2-linux-c5bedc6847c3be6efe0e671a6155c9a25fd468bf.tar.gz kernel-qcow2-linux-c5bedc6847c3be6efe0e671a6155c9a25fd468bf.tar.xz kernel-qcow2-linux-c5bedc6847c3be6efe0e671a6155c9a25fd468bf.zip | |
x86/fpu: Get rid of PF_USED_MATH usage, convert it to fpu->fpstate_active
Introduce a simple fpu->fpstate_active flag in the fpu context data structure
and use that instead of PF_USED_MATH in task->flags.
Testing for this flag byte should be slightly more efficient than
testing a bit in a bitmask, but the main advantage is that most
FPU functions can now be performed on a 'struct fpu' alone, they
don't need access to 'struct task_struct' anymore.
There's a slight linecount increase, mostly due to the 'fpu' local
variables and due to extra comments. The local variables will go away
once we move most of the FPU methods to pure 'struct fpu' parameters.
Reviewed-by: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/kvm/x86.c')
| -rw-r--r-- | arch/x86/kvm/x86.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 0635a1fd43ba..bab8afb61dc1 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -6597,10 +6597,11 @@ static int complete_emulated_mmio(struct kvm_vcpu *vcpu) int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run) { + struct fpu *fpu = ¤t->thread.fpu; int r; sigset_t sigsaved; - if (!(current->flags & PF_USED_MATH) && fpstate_alloc_init(current)) + if (!fpu->fpstate_active && fpstate_alloc_init(current)) return -ENOMEM; if (vcpu->sigset_active) |