x86/cpufeature: Replace cpu_has_fpu with boot_cpu_has() usage

Use static_cpu_has() in the timing-sensitive paths in fpstate_init() and
fpu__copy().

While at it, simplify the use in init_cyrix() and get rid of the ternary
operator.

Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/1459801503-15600-6-git-send-email-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/arch/x86/include/asm/cpufeature.h b/arch/x86/include/asm/cpufeature.h
index 6463258..b23d557 100644 (file)
--- a/arch/x86/include/asm/cpufeature.h
+++ b/arch/x86/include/asm/cpufeature.h
@@ -118,7 +118,6 @@ extern const char * const x86_bug_flags[NBUGINTS*32];
        set_bit(bit, (unsigned long *)cpu_caps_set);    \
 } while (0)
 
-#define cpu_has_fpu            boot_cpu_has(X86_FEATURE_FPU)
 #define cpu_has_tsc            boot_cpu_has(X86_FEATURE_TSC)
 #define cpu_has_apic           boot_cpu_has(X86_FEATURE_APIC)
 #define cpu_has_fxsr           boot_cpu_has(X86_FEATURE_FXSR)

diff --git a/arch/x86/kernel/cpu/cyrix.c b/arch/x86/kernel/cpu/cyrix.c
index 6adef9c..bd9dcd6 100644 (file)
--- a/arch/x86/kernel/cpu/cyrix.c
+++ b/arch/x86/kernel/cpu/cyrix.c
@@ -333,7 +333,7 @@ static void init_cyrix(struct cpuinfo_x86 *c)
                switch (dir0_lsn) {
                case 0xd:  /* either a 486SLC or DLC w/o DEVID */
                        dir0_msn = 0;
-                       p = Cx486_name[(cpu_has_fpu ? 1 : 0)];
+                       p = Cx486_name[!!boot_cpu_has(X86_FEATURE_FPU)];
                        break;
 
                case 0xe:  /* a 486S A step */

diff --git a/arch/x86/kernel/fpu/bugs.c b/arch/x86/kernel/fpu/bugs.c
index dd9ca9b..224b5ec 100644 (file)
--- a/arch/x86/kernel/fpu/bugs.c
+++ b/arch/x86/kernel/fpu/bugs.c
@@ -66,6 +66,6 @@ void __init fpu__init_check_bugs(void)
         * kernel_fpu_begin/end() in check_fpu() relies on the patched
         * alternative instructions.
         */
-       if (cpu_has_fpu)
+       if (boot_cpu_has(X86_FEATURE_FPU))
                check_fpu();
 }

diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c
index b05aa68..0e7859f 100644 (file)
--- a/arch/x86/kernel/fpu/core.c
+++ b/arch/x86/kernel/fpu/core.c
@@ -217,7 +217,7 @@ static inline void fpstate_init_fstate(struct fregs_state *fp)
 
 void fpstate_init(union fpregs_state *state)
 {
-       if (!cpu_has_fpu) {
+       if (!static_cpu_has(X86_FEATURE_FPU)) {
                fpstate_init_soft(&state->soft);
                return;
        }
@@ -237,7 +237,7 @@ int fpu__copy(struct fpu *dst_fpu, struct fpu *src_fpu)
        dst_fpu->fpregs_active = 0;
        dst_fpu->last_cpu = -1;
 
-       if (!src_fpu->fpstate_active || !cpu_has_fpu)
+       if (!src_fpu->fpstate_active || !static_cpu_has(X86_FEATURE_FPU))
                return 0;
 
        WARN_ON_FPU(src_fpu != &current->thread.fpu);

diff --git a/arch/x86/kernel/fpu/init.c b/arch/x86/kernel/fpu/init.c
index 9bbb332..3a84275 100644 (file)
--- a/arch/x86/kernel/fpu/init.c
+++ b/arch/x86/kernel/fpu/init.c
@@ -38,13 +38,13 @@ static void fpu__init_cpu_generic(void)
 
        cr0 = read_cr0();
        cr0 &= ~(X86_CR0_TS|X86_CR0_EM); /* clear TS and EM */
-       if (!cpu_has_fpu)
+       if (!boot_cpu_has(X86_FEATURE_FPU))
                cr0 |= X86_CR0_EM;
        write_cr0(cr0);
 
        /* Flush out any pending x87 state: */
 #ifdef CONFIG_MATH_EMULATION
-       if (!cpu_has_fpu)
+       if (!boot_cpu_has(X86_FEATURE_FPU))
                fpstate_init_soft(&current->thread.fpu.state.soft);
        else
 #endif
@@ -89,7 +89,7 @@ static void fpu__init_system_early_generic(struct cpuinfo_x86 *c)
        }
 
 #ifndef CONFIG_MATH_EMULATION
-       if (!cpu_has_fpu) {
+       if (!boot_cpu_has(X86_FEATURE_FPU)) {
                pr_emerg("x86/fpu: Giving up, no FPU found and no math emulation present\n");
                for (;;)
                        asm volatile("hlt");
@@ -212,7 +212,7 @@ static void __init fpu__init_system_xstate_size_legacy(void)
         * fpu__init_system_xstate().
         */
 
-       if (!cpu_has_fpu) {
+       if (!boot_cpu_has(X86_FEATURE_FPU)) {
                /*
                 * Disable xsave as we do not support it if i387
                 * emulation is enabled.