diff options
| author | David Woodhouse <David.Woodhouse@intel.com> | 2012-10-09 15:03:21 +0100 |
|---|---|---|
| committer | David Woodhouse <David.Woodhouse@intel.com> | 2012-10-09 15:04:25 +0100 |
| commit | ffe315012510165ce82e4dd4767f0a5dba9edbf7 (patch) | |
| tree | f601cd980af9d0ced5ca9aedecef4fa0d2ca0e15 /arch/x86/include/asm/i387.h | |
| parent | e2d3a35ee427aaba99b6c68a56609ce276c51270 (diff) | |
| parent | 4a8e43feeac7996b8de2d5b2823e316917493df4 (diff) | |
Merge tag 'disintegrate-mtd-20121009' of git://git.infradead.org/users/dhowells/linux-headers
UAPI Disintegration 2012-10-09
Conflicts:
MAINTAINERS
arch/arm/configs/bcmring_defconfig
arch/arm/mach-imx/clk-imx51-imx53.c
drivers/mtd/nand/Kconfig
drivers/mtd/nand/bcm_umi_nand.c
drivers/mtd/nand/nand_bcm_umi.h
drivers/mtd/nand/orion_nand.c
Diffstat (limited to 'arch/x86/include/asm/i387.h')
| -rw-r--r-- | arch/x86/include/asm/i387.h | 29 |
1 files changed, 27 insertions, 2 deletions
diff --git a/arch/x86/include/asm/i387.h b/arch/x86/include/asm/i387.h index 257d9cca214f..ed8089d69094 100644 --- a/arch/x86/include/asm/i387.h +++ b/arch/x86/include/asm/i387.h @@ -19,12 +19,37 @@ struct pt_regs; struct user_i387_struct; extern int init_fpu(struct task_struct *child); +extern void fpu_finit(struct fpu *fpu); extern int dump_fpu(struct pt_regs *, struct user_i387_struct *); extern void math_state_restore(void); extern bool irq_fpu_usable(void); -extern void kernel_fpu_begin(void); -extern void kernel_fpu_end(void); + +/* + * Careful: __kernel_fpu_begin/end() must be called with preempt disabled + * and they don't touch the preempt state on their own. + * If you enable preemption after __kernel_fpu_begin(), preempt notifier + * should call the __kernel_fpu_end() to prevent the kernel/user FPU + * state from getting corrupted. KVM for example uses this model. + * + * All other cases use kernel_fpu_begin/end() which disable preemption + * during kernel FPU usage. + */ +extern void __kernel_fpu_begin(void); +extern void __kernel_fpu_end(void); + +static inline void kernel_fpu_begin(void) +{ + WARN_ON_ONCE(!irq_fpu_usable()); + preempt_disable(); + __kernel_fpu_begin(); +} + +static inline void kernel_fpu_end(void) +{ + __kernel_fpu_end(); + preempt_enable(); +} /* * Some instructions like VIA's padlock instructions generate a spurious |