From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755356Ab1K2Mnu (ORCPT ); Tue, 29 Nov 2011 07:43:50 -0500 Received: from ch1ehsobe002.messaging.microsoft.com ([216.32.181.182]:9532 "EHLO ch1outboundpool.messaging.microsoft.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753680Ab1K2Mmy (ORCPT ); Tue, 29 Nov 2011 07:42:54 -0500 X-SpamScore: 0 X-BigFish: VPS0(zzzz1202hzz8275bhz2dh668h839h) X-Forefront-Antispam-Report: CIP:163.181.249.108;KIP:(null);UIP:(null);IPV:NLI;H:ausb3twp01.amd.com;RD:none;EFVD:NLI X-WSS-ID: 0LVF9ZB-01-CSJ-02 X-M-MSG: From: Hans Rosenfeld To: CC: , , , , , , , , , Hans Rosenfeld Subject: [PATCH 6/9] x86, xsave: more cleanups Date: Tue, 29 Nov 2011 13:41:25 +0100 Message-ID: <1322570488-21798-7-git-send-email-hans.rosenfeld@amd.com> X-Mailer: git-send-email 1.7.5.4 In-Reply-To: <1322570488-21798-1-git-send-email-hans.rosenfeld@amd.com> References: <1322570488-21798-1-git-send-email-hans.rosenfeld@amd.com> MIME-Version: 1.0 Content-Type: text/plain X-OriginatorOrg: amd.com Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Removed some declarations from headers that weren't used. Retired TS_USEDFPU, it has been replaced by the XCNTXT_* bits in xstate_mask. There is no reason functions like fpu_fxsave() etc. need to know or handle anything else than a buffer to save/restore their stuff to/from. Sanitize_i387_state() is extra work that is only needed when xsaveopt is used. There is no point in hiding this in an inline function, adding extra code lines just to save a single if() in the five places it is used. Also, it is obscuring a fact that might well be interesting to whoever is reading the code, but it is not gaining anything. Signed-off-by: Hans Rosenfeld --- arch/x86/include/asm/i387.h | 66 ++++++++++++----------------------- arch/x86/include/asm/thread_info.h | 2 - arch/x86/include/asm/xsave.h | 14 +++---- arch/x86/kernel/i387.c | 12 ++++-- arch/x86/kernel/xsave.c | 35 ++++++++----------- arch/x86/kvm/vmx.c | 2 +- arch/x86/kvm/x86.c | 4 +- 7 files changed, 55 insertions(+), 80 deletions(-) diff --git a/arch/x86/include/asm/i387.h b/arch/x86/include/asm/i387.h index 687e550..3474267 100644 --- a/arch/x86/include/asm/i387.h +++ b/arch/x86/include/asm/i387.h @@ -59,15 +59,10 @@ extern user_regset_set_fn fpregs_set, xfpregs_set, fpregs_soft_set, */ #define xstateregs_active fpregs_active -extern struct _fpx_sw_bytes fx_sw_reserved; extern unsigned int mxcsr_feature_mask; + #ifdef CONFIG_IA32_EMULATION extern unsigned int sig_xstate_ia32_size; -extern struct _fpx_sw_bytes fx_sw_reserved_ia32; -struct _fpstate_ia32; -struct _xstate_ia32; -extern int save_i387_xstate_ia32(void __user *buf); -extern int restore_i387_xstate_ia32(void __user *buf); #endif #ifdef CONFIG_MATH_EMULATION @@ -75,7 +70,7 @@ extern int restore_i387_xstate_ia32(void __user *buf); extern void finit_soft_fpu(struct i387_soft_struct *soft); #else # define HAVE_HWFP 1 -static inline void finit_soft_fpu(struct i387_soft_struct *soft) {} +# define finit_soft_fpu(x) #endif #define X87_FSW_ES (1 << 7) /* Exception Summary */ @@ -95,15 +90,6 @@ static __always_inline __pure bool use_fxsr(void) return static_cpu_has(X86_FEATURE_FXSR); } -extern void __sanitize_i387_state(struct task_struct *); - -static inline void sanitize_i387_state(struct task_struct *tsk) -{ - if (!use_xsaveopt()) - return; - __sanitize_i387_state(tsk); -} - #ifdef CONFIG_X86_64 static inline void fxrstor(struct i387_fxsave_struct *fx) { @@ -117,7 +103,7 @@ static inline void fxrstor(struct i387_fxsave_struct *fx) #endif } -static inline void fpu_fxsave(struct fpu *fpu) +static inline void fpu_fxsave(struct i387_fxsave_struct *fx) { /* Using "rex64; fxsave %0" is broken because, if the memory operand uses any extended registers for addressing, a second REX prefix @@ -128,7 +114,7 @@ static inline void fpu_fxsave(struct fpu *fpu) /* Using "fxsaveq %0" would be the ideal choice, but is only supported starting with gas 2.16. */ __asm__ __volatile__("fxsaveq %0" - : "=m" (fpu->state->fxsave)); + : "=m" (*fx)); #else /* Using, as a workaround, the properly prefixed form below isn't accepted by any binutils version so far released, complaining that @@ -139,8 +125,8 @@ static inline void fpu_fxsave(struct fpu *fpu) This, however, we can work around by forcing the compiler to select an addressing mode that doesn't require extended registers. */ asm volatile("rex64/fxsave (%[fx])" - : "=m" (fpu->state->fxsave) - : [fx] "R" (&fpu->state->fxsave)); + : "=m" (*fx) + : [fx] "R" (fx)); #endif } @@ -160,10 +146,10 @@ static inline void fxrstor(struct i387_fxsave_struct *fx) "m" (*fx)); } -static inline void fpu_fxsave(struct fpu *fpu) +static inline void fpu_fxsave(struct i387_fxsave_struct *fx) { asm volatile("fxsave %[fx]" - : [fx] "=m" (fpu->state->fxsave)); + : [fx] "=m" (*fx)); } #endif /* CONFIG_X86_64 */ @@ -180,25 +166,25 @@ static inline void fpu_fxsave(struct fpu *fpu) /* * These must be called with preempt disabled */ -static inline void fpu_restore(struct fpu *fpu) +static inline void fpu_restore(struct i387_fxsave_struct *fx) { - fxrstor(&fpu->state->fxsave); + fxrstor(fx); } -static inline void fpu_save(struct fpu *fpu) +static inline void fpu_save(struct i387_fxsave_struct *fx) { if (use_fxsr()) { - fpu_fxsave(fpu); + fpu_fxsave(fx); } else { asm volatile("fsave %[fx]; fwait" - : [fx] "=m" (fpu->state->fsave)); + : [fx] "=m" (*fx)); } } -static inline void fpu_clean(struct fpu *fpu) +static inline void fpu_clean(struct i387_fxsave_struct *fx) { u32 swd = (use_fxsr() || use_xsave()) ? - fpu->state->fxsave.swd : fpu->state->fsave.swd; + fx->swd : ((struct i387_fsave_struct *)fx)->swd; if (unlikely(swd & X87_FSW_ES)) asm volatile("fnclex"); @@ -214,19 +200,6 @@ static inline void fpu_clean(struct fpu *fpu) [addr] "m" (safe_address)); } -static inline void __clear_fpu(struct task_struct *tsk) -{ - if (task_thread_info(tsk)->status & TS_USEDFPU) { - /* Ignore delayed exceptions from user space */ - asm volatile("1: fwait\n" - "2:\n" - _ASM_EXTABLE(1b, 2b)); - task_thread_info(tsk)->status &= ~TS_USEDFPU; - task_thread_info(tsk)->xstate_mask &= ~XCNTXT_LAZY; - stts(); - } -} - static inline void kernel_fpu_begin(void) { preempt_disable(); @@ -285,7 +258,14 @@ static inline void irq_ts_restore(int TS_state) static inline void clear_fpu(struct task_struct *tsk) { preempt_disable(); - __clear_fpu(tsk); + if (task_thread_info(tsk)->xstate_mask & XCNTXT_LAZY) { + /* Ignore delayed exceptions from user space */ + asm volatile("1: fwait\n" + "2:\n" + _ASM_EXTABLE(1b, 2b)); + task_thread_info(tsk)->xstate_mask &= ~XCNTXT_LAZY; + stts(); + } preempt_enable(); } diff --git a/arch/x86/include/asm/thread_info.h b/arch/x86/include/asm/thread_info.h index 6652c9b..02112a7 100644 --- a/arch/x86/include/asm/thread_info.h +++ b/arch/x86/include/asm/thread_info.h @@ -244,8 +244,6 @@ static inline struct thread_info *current_thread_info(void) * ever touches our thread-synchronous status, so we don't * have to worry about atomic accesses. */ -#define TS_USEDFPU 0x0001 /* FPU was used by this task - this quantum (SMP) */ #define TS_COMPAT 0x0002 /* 32bit syscall active (64BIT)*/ #define TS_POLLING 0x0004 /* idle task polling need_resched, skip sending interrupt */ diff --git a/arch/x86/include/asm/xsave.h b/arch/x86/include/asm/xsave.h index 8d5bb0e..12793b6 100644 --- a/arch/x86/include/asm/xsave.h +++ b/arch/x86/include/asm/xsave.h @@ -37,8 +37,8 @@ extern unsigned int xstate_size; extern u64 pcntxt_mask; extern u64 xstate_fx_sw_bytes[USER_XSTATE_FX_SW_WORDS]; -extern void xsave(struct fpu *, u64); -extern void xrstor(struct fpu *, u64); +extern void xsave(struct xsave_struct *, u64); +extern void xrstor(struct xsave_struct *, u64); extern void __save_xstates(struct task_struct *); extern void __restore_xstates(struct task_struct *, u64); extern int save_xstates_sigframe(void __user *, unsigned int); @@ -46,10 +46,7 @@ extern int restore_xstates_sigframe(void __user *, unsigned int); extern void xsave_init(void); extern void update_regset_xstate_info(unsigned int size, u64 xstate_mask); -extern int init_fpu(struct task_struct *child); -extern int check_for_xstate(struct i387_fxsave_struct __user *buf, - unsigned int size, - struct _fpx_sw_bytes *sw); +extern void sanitize_i387_state(struct task_struct *); static inline void save_xstates(struct task_struct *tsk) { @@ -85,7 +82,7 @@ static inline void xsave_state(struct xsave_struct *fx, u64 mask) : "memory"); } -static inline void fpu_xsave(struct xsave_struct *fx, u64 mask) +static inline void xsaveopt_state(struct xsave_struct *fx, u64 mask) { u32 lmask = mask; u32 hmask = mask >> 32; @@ -96,7 +93,8 @@ static inline void fpu_xsave(struct xsave_struct *fx, u64 mask) ".byte " REX_PREFIX "0x0f,0xae,0x27", ".byte " REX_PREFIX "0x0f,0xae,0x37", X86_FEATURE_XSAVEOPT, - [fx] "D" (fx), "a" (lmask), "d" (hmask) : + "D" (fx), "a" (lmask), "d" (hmask) : "memory"); } + #endif diff --git a/arch/x86/kernel/i387.c b/arch/x86/kernel/i387.c index 49d23a5..a1f4bc0 100644 --- a/arch/x86/kernel/i387.c +++ b/arch/x86/kernel/i387.c @@ -179,7 +179,8 @@ int xfpregs_get(struct task_struct *target, const struct user_regset *regset, if (ret) return ret; - sanitize_i387_state(target); + if (use_xsaveopt()) + sanitize_i387_state(target); return user_regset_copyout(&pos, &count, &kbuf, &ubuf, &target->thread.fpu.state->fxsave, 0, -1); @@ -198,7 +199,8 @@ int xfpregs_set(struct task_struct *target, const struct user_regset *regset, if (ret) return ret; - sanitize_i387_state(target); + if (use_xsaveopt()) + sanitize_i387_state(target); ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &target->thread.fpu.state->fxsave, 0, -1); @@ -437,7 +439,8 @@ int fpregs_get(struct task_struct *target, const struct user_regset *regset, -1); } - sanitize_i387_state(target); + if (use_xsaveopt()) + sanitize_i387_state(target); if (kbuf && pos == 0 && count == sizeof(env)) { convert_from_fxsr(kbuf, target); @@ -460,7 +463,8 @@ int fpregs_set(struct task_struct *target, const struct user_regset *regset, if (ret) return ret; - sanitize_i387_state(target); + if (use_xsaveopt()) + sanitize_i387_state(target); if (!HAVE_HWFP) return fpregs_soft_set(target, regset, pos, count, kbuf, ubuf); diff --git a/arch/x86/kernel/xsave.c b/arch/x86/kernel/xsave.c index ca5812c..9d95d2f 100644 --- a/arch/x86/kernel/xsave.c +++ b/arch/x86/kernel/xsave.c @@ -39,7 +39,7 @@ static unsigned int *xstate_offsets, *xstate_sizes, xstate_features; * that the user doesn't see some stale state in the memory layout during * signal handling, debugging etc. */ -void __sanitize_i387_state(struct task_struct *tsk) +void sanitize_i387_state(struct task_struct *tsk) { u64 xstate_bv; int feature_bit = 0x2; @@ -49,7 +49,6 @@ void __sanitize_i387_state(struct task_struct *tsk) return; BUG_ON(task_thread_info(tsk)->xstate_mask & XCNTXT_LAZY); - BUG_ON(task_thread_info(tsk)->status & TS_USEDFPU); xstate_bv = tsk->thread.fpu.state->xsave.xsave_hdr.xstate_bv; @@ -104,8 +103,8 @@ void __sanitize_i387_state(struct task_struct *tsk) * Check for the presence of extended state information in the * user fpstate pointer in the sigcontext. */ -int check_for_xstate(struct i387_fxsave_struct __user *buf, unsigned int size, - struct _fpx_sw_bytes *fx_sw_user) +static int check_for_xstate(struct i387_fxsave_struct __user *buf, unsigned int size, + struct _fpx_sw_bytes *fx_sw_user) { int min_xstate_size = sizeof(struct i387_fxsave_struct) + sizeof(struct xsave_hdr_struct); @@ -178,7 +177,8 @@ int save_xstates_sigframe(void __user *buf, unsigned int size) tsk->fpu_counter = 0; save_xstates(tsk); - sanitize_i387_state(tsk); + if (use_xsaveopt()) + sanitize_i387_state(tsk); #if defined(CONFIG_X86_32) || defined(CONFIG_IA32_EMULATION) if (ia32) { @@ -299,7 +299,6 @@ int restore_xstates_sigframe(void __user *buf, unsigned int size) preempt_disable(); stts(); - task_thread_info(tsk)->status &= ~TS_USEDFPU; task_thread_info(tsk)->xstate_mask = 0; preempt_enable(); @@ -505,17 +504,17 @@ void __cpuinit xsave_init(void) this_func(); } -void xsave(struct fpu *fpu, u64 mask) +void xsave(struct xsave_struct *x, u64 mask) { clts(); if (use_xsave()) - fpu_xsave(&fpu->state->xsave, mask); + xsaveopt_state(x, mask); else if (mask & XCNTXT_LAZY) - fpu_save(fpu); + fpu_save(&x->i387); if (mask & XCNTXT_LAZY) - fpu_clean(fpu); + fpu_clean(&x->i387); stts(); } @@ -528,7 +527,7 @@ void __save_xstates(struct task_struct *tsk) if (!fpu_allocated(&tsk->thread.fpu)) return; - xsave(&tsk->thread.fpu, ti->xstate_mask); + xsave(&tsk->thread.fpu.state->xsave, ti->xstate_mask); if (!(ti->xstate_mask & XCNTXT_LAZY)) tsk->fpu_counter = 0; @@ -540,19 +539,17 @@ void __save_xstates(struct task_struct *tsk) */ if (tsk->fpu_counter < 5) ti->xstate_mask &= ~XCNTXT_LAZY; - - ti->status &= ~TS_USEDFPU; } EXPORT_SYMBOL(save_xstates); -void xrstor(struct fpu *fpu, u64 mask) +void xrstor(struct xsave_struct *x, u64 mask) { clts(); if (use_xsave()) - xrstor_state(&fpu->state->xsave, mask); + xrstor_state(x, mask); else if (mask & XCNTXT_LAZY) - fpu_restore(fpu); + fpu_restore(&x->i387); if (!(mask & XCNTXT_LAZY)) stts(); @@ -566,12 +563,10 @@ void __restore_xstates(struct task_struct *tsk, u64 mask) if (!fpu_allocated(&tsk->thread.fpu)) return; - xrstor(&tsk->thread.fpu, mask); + xrstor(&tsk->thread.fpu.state->xsave, mask); ti->xstate_mask |= mask; - if (mask & XCNTXT_LAZY) { - ti->status |= TS_USEDFPU; + if (mask & XCNTXT_LAZY) tsk->fpu_counter++; - } } EXPORT_SYMBOL(__restore_xstates); diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index e65a158..e41385f 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -1402,7 +1402,7 @@ static void __vmx_load_host_state(struct vcpu_vmx *vmx) #ifdef CONFIG_X86_64 wrmsrl(MSR_KERNEL_GS_BASE, vmx->msr_host_kernel_gs_base); #endif - if (current_thread_info()->status & TS_USEDFPU) + if (current_thread_info()->xstate_mask & XCNTXT_LAZY) clts(); load_gdt(&__get_cpu_var(host_gdt)); } diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index d14fd8c..36bc63d 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -6259,7 +6259,7 @@ void kvm_load_guest_fpu(struct kvm_vcpu *vcpu) kvm_put_guest_xcr0(vcpu); vcpu->guest_fpu_loaded = 1; save_xstates(current); - xrstor(&vcpu->arch.guest_fpu, -1); + xrstor(&vcpu->arch.guest_fpu.state->xsave, -1); trace_kvm_fpu(1); } @@ -6271,7 +6271,7 @@ void kvm_put_guest_fpu(struct kvm_vcpu *vcpu) return; vcpu->guest_fpu_loaded = 0; - xsave(&vcpu->arch.guest_fpu, -1); + xsave(&vcpu->arch.guest_fpu.state->xsave, -1); ++vcpu->stat.fpu_reload; kvm_make_request(KVM_REQ_DEACTIVATE_FPU, vcpu); trace_kvm_fpu(0); -- 1.7.5.4