diff options
Diffstat (limited to 'arch/x86/kernel/fpu/core.c')
-rw-r--r-- | arch/x86/kernel/fpu/core.c | 39 |
1 files changed, 4 insertions, 35 deletions
diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c index 430c095cfa0e..fc965118d2e6 100644 --- a/arch/x86/kernel/fpu/core.c +++ b/arch/x86/kernel/fpu/core.c @@ -59,27 +59,9 @@ static bool kernel_fpu_disabled(void) return this_cpu_read(in_kernel_fpu); } -/* - * Were we in an interrupt that interrupted kernel mode? - * - * On others, we can do a kernel_fpu_begin/end() pair *ONLY* if that - * pair does nothing at all: the thread must not have fpu (so - * that we don't try to save the FPU state), and TS must - * be set (so that the clts/stts pair does nothing that is - * visible in the interrupted kernel thread). - * - * Except for the eagerfpu case when we return true; in the likely case - * the thread has FPU but we are not going to set/clear TS. - */ static bool interrupted_kernel_fpu_idle(void) { - if (kernel_fpu_disabled()) - return false; - - if (use_eager_fpu()) - return true; - - return !current->thread.fpu.fpregs_active && (read_cr0() & X86_CR0_TS); + return !kernel_fpu_disabled(); } /* @@ -127,7 +109,6 @@ void __kernel_fpu_begin(void) copy_fpregs_to_fpstate(fpu); } else { this_cpu_write(fpu_fpregs_owner_ctx, NULL); - __fpregs_activate_hw(); } } EXPORT_SYMBOL(__kernel_fpu_begin); @@ -138,8 +119,6 @@ void __kernel_fpu_end(void) if (fpu->fpregs_active) copy_kernel_to_fpregs(&fpu->state); - else - __fpregs_deactivate_hw(); kernel_fpu_enable(); } @@ -201,10 +180,7 @@ void fpu__save(struct fpu *fpu) trace_x86_fpu_before_save(fpu); if (fpu->fpregs_active) { if (!copy_fpregs_to_fpstate(fpu)) { - if (use_eager_fpu()) - copy_kernel_to_fpregs(&fpu->state); - else - fpregs_deactivate(fpu); + copy_kernel_to_fpregs(&fpu->state); } } trace_x86_fpu_after_save(fpu); @@ -249,7 +225,6 @@ EXPORT_SYMBOL_GPL(fpstate_init); int fpu__copy(struct fpu *dst_fpu, struct fpu *src_fpu) { - dst_fpu->counter = 0; dst_fpu->fpregs_active = 0; dst_fpu->last_cpu = -1; @@ -262,8 +237,7 @@ int fpu__copy(struct fpu *dst_fpu, struct fpu *src_fpu) * Don't let 'init optimized' areas of the XSAVE area * leak into the child task: */ - if (use_eager_fpu()) - memset(&dst_fpu->state.xsave, 0, fpu_kernel_xstate_size); + memset(&dst_fpu->state.xsave, 0, fpu_kernel_xstate_size); /* * Save current FPU registers directly into the child @@ -285,10 +259,7 @@ int fpu__copy(struct fpu *dst_fpu, struct fpu *src_fpu) memcpy(&src_fpu->state, &dst_fpu->state, fpu_kernel_xstate_size); - if (use_eager_fpu()) - copy_kernel_to_fpregs(&src_fpu->state); - else - fpregs_deactivate(src_fpu); + copy_kernel_to_fpregs(&src_fpu->state); } preempt_enable(); @@ -461,7 +432,6 @@ void fpu__restore(struct fpu *fpu) trace_x86_fpu_before_restore(fpu); fpregs_activate(fpu); copy_kernel_to_fpregs(&fpu->state); - fpu->counter++; trace_x86_fpu_after_restore(fpu); kernel_fpu_enable(); } @@ -479,7 +449,6 @@ EXPORT_SYMBOL_GPL(fpu__restore); void fpu__drop(struct fpu *fpu) { preempt_disable(); - fpu->counter = 0; if (fpu->fpregs_active) { /* Ignore delayed exceptions from user space */ |