From 276983f8085db4a5f4e2cdcda6bce29a1da97eb0 Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Thu, 23 Apr 2015 11:55:18 +0200 Subject: [PATCH] x86/fpu: Eliminate the __thread_has_fpu() wrapper Start migrating FPU methods towards using 'struct fpu *fpu' directly. __thread_has_fpu() is just a trivial wrapper around fpu->has_fpu, eliminate it. Reviewed-by: Borislav Petkov Cc: Andy Lutomirski Cc: Dave Hansen Cc: Fenghua Yu Cc: H. Peter Anvin Cc: Linus Torvalds Cc: Oleg Nesterov Cc: Peter Zijlstra Cc: Thomas Gleixner Signed-off-by: Ingo Molnar --- arch/x86/include/asm/fpu-internal.h | 16 ++++------------ arch/x86/kernel/fpu/core.c | 17 ++++++++++------- 2 files changed, 14 insertions(+), 19 deletions(-) diff --git a/arch/x86/include/asm/fpu-internal.h b/arch/x86/include/asm/fpu-internal.h index e180fb96dd0d..c005d1fc1247 100644 --- a/arch/x86/include/asm/fpu-internal.h +++ b/arch/x86/include/asm/fpu-internal.h @@ -323,16 +323,6 @@ static inline int restore_fpu_checking(struct task_struct *tsk) return fpu_restore_checking(&tsk->thread.fpu); } -/* - * Software FPU state helpers. Careful: these need to - * be preemption protection *and* they need to be - * properly paired with the CR0.TS changes! - */ -static inline int __thread_has_fpu(struct task_struct *tsk) -{ - return tsk->thread.fpu.has_fpu; -} - /* Must be paired with an 'stts' after! */ static inline void __thread_clear_has_fpu(struct task_struct *tsk) { @@ -370,13 +360,14 @@ static inline void __thread_fpu_begin(struct task_struct *tsk) static inline void drop_fpu(struct task_struct *tsk) { + struct fpu *fpu = &tsk->thread.fpu; /* * Forget coprocessor state.. */ preempt_disable(); tsk->thread.fpu.counter = 0; - if (__thread_has_fpu(tsk)) { + if (fpu->has_fpu) { /* Ignore delayed exceptions from user space */ asm volatile("1: fwait\n" "2:\n" @@ -424,6 +415,7 @@ typedef struct { int preload; } fpu_switch_t; static inline fpu_switch_t switch_fpu_prepare(struct task_struct *old, struct task_struct *new, int cpu) { + struct fpu *old_fpu = &old->thread.fpu; fpu_switch_t fpu; /* @@ -433,7 +425,7 @@ static inline fpu_switch_t switch_fpu_prepare(struct task_struct *old, struct ta fpu.preload = tsk_used_math(new) && (use_eager_fpu() || new->thread.fpu.counter > 5); - if (__thread_has_fpu(old)) { + if (old_fpu->has_fpu) { if (!fpu_save_init(&old->thread.fpu)) task_disable_lazy_fpu_restore(old); else diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c index 3aeab3f12835..29b837730a07 100644 --- a/arch/x86/kernel/fpu/core.c +++ b/arch/x86/kernel/fpu/core.c @@ -57,8 +57,7 @@ static bool interrupted_kernel_fpu_idle(void) if (use_eager_fpu()) return true; - return !__thread_has_fpu(current) && - (read_cr0() & X86_CR0_TS); + return !current->thread.fpu.has_fpu && (read_cr0() & X86_CR0_TS); } /* @@ -93,11 +92,12 @@ EXPORT_SYMBOL(irq_fpu_usable); void __kernel_fpu_begin(void) { struct task_struct *me = current; + struct fpu *fpu = &me->thread.fpu; kernel_fpu_disable(); - if (__thread_has_fpu(me)) { - fpu_save_init(&me->thread.fpu); + if (fpu->has_fpu) { + fpu_save_init(fpu); } else { this_cpu_write(fpu_owner_task, NULL); if (!use_eager_fpu()) @@ -109,8 +109,9 @@ EXPORT_SYMBOL(__kernel_fpu_begin); void __kernel_fpu_end(void) { struct task_struct *me = current; + struct fpu *fpu = &me->thread.fpu; - if (__thread_has_fpu(me)) { + if (fpu->has_fpu) { if (WARN_ON(restore_fpu_checking(me))) fpu_reset_state(me); } else if (!use_eager_fpu()) { @@ -128,14 +129,16 @@ EXPORT_SYMBOL(__kernel_fpu_end); */ void fpu__save(struct task_struct *tsk) { + struct fpu *fpu = &tsk->thread.fpu; + WARN_ON(tsk != current); preempt_disable(); - if (__thread_has_fpu(tsk)) { + if (fpu->has_fpu) { if (use_eager_fpu()) { __save_fpu(tsk); } else { - fpu_save_init(&tsk->thread.fpu); + fpu_save_init(fpu); __thread_fpu_end(tsk); } } -- 2.39.5