Commit-ID: 9ad93fe35aff616fca4e2b9581fdeed498605f9e Gitweb: http://git.kernel.org/tip/9ad93fe35aff616fca4e2b9581fdeed498605f9e Author: Rik van Riel <r...@redhat.com> AuthorDate: Tue, 4 Oct 2016 20:34:38 -0400 Committer: Ingo Molnar <mi...@kernel.org> CommitDate: Fri, 7 Oct 2016 11:14:43 +0200
x86/fpu: Split old & new FPU code paths Now that CR0.TS is no longer being manipulated, we can simplify switch_fpu_prepare() by no longer nesting the handling of new_fpu inside the two branches for the old_fpu. Signed-off-by: Rik van Riel <r...@redhat.com> Cc: Andy Lutomirski <l...@kernel.org> Cc: Borislav Petkov <b...@alien8.de> Cc: Brian Gerst <brge...@gmail.com> Cc: Dave Hansen <dave.han...@linux.intel.com> Cc: Denys Vlasenko <dvlas...@redhat.com> Cc: Fenghua Yu <fenghua...@intel.com> Cc: H. Peter Anvin <h...@zytor.com> Cc: Josh Poimboeuf <jpoim...@redhat.com> Cc: Linus Torvalds <torva...@linux-foundation.org> Cc: Oleg Nesterov <o...@redhat.com> Cc: Peter Zijlstra <pet...@infradead.org> Cc: Quentin Casasnovas <quentin.casasno...@oracle.com> Cc: Thomas Gleixner <t...@linutronix.de> Cc: pbonz...@redhat.com Link: http://lkml.kernel.org/r/1475627678-20788-10-git-send-email-r...@redhat.com Signed-off-by: Ingo Molnar <mi...@kernel.org> --- arch/x86/include/asm/fpu/internal.h | 22 ++++++++-------------- 1 file changed, 8 insertions(+), 14 deletions(-) diff --git a/arch/x86/include/asm/fpu/internal.h b/arch/x86/include/asm/fpu/internal.h index d0324bc..1dcb29e 100644 --- a/arch/x86/include/asm/fpu/internal.h +++ b/arch/x86/include/asm/fpu/internal.h @@ -581,23 +581,17 @@ switch_fpu_prepare(struct fpu *old_fpu, struct fpu *new_fpu, int cpu) /* But leave fpu_fpregs_owner_ctx! */ old_fpu->fpregs_active = 0; trace_x86_fpu_regs_deactivated(old_fpu); + } else + old_fpu->last_cpu = -1; - /* Don't change CR0.TS if we just switch! */ - if (fpu.preload) { - fpregs_activate(new_fpu); - trace_x86_fpu_regs_activated(new_fpu); + if (fpu.preload) { + if (fpregs_state_valid(new_fpu, cpu)) + fpu.preload = 0; + else prefetch(&new_fpu->state); - } - } else { - old_fpu->last_cpu = -1; - if (fpu.preload) { - if (fpregs_state_valid(new_fpu, cpu)) - fpu.preload = 0; - else - prefetch(&new_fpu->state); - fpregs_activate(new_fpu); - } + fpregs_activate(new_fpu); } + return fpu; }
