diff options
| author | Arnd Bergmann <arnd@arndb.de> | 2012-10-04 22:57:00 +0200 |
|---|---|---|
| committer | Arnd Bergmann <arnd@arndb.de> | 2012-10-04 22:57:51 +0200 |
| commit | c37d6154c0b9163c27e53cc1d0be3867b4abd760 (patch) | |
| tree | 7a24522c56d1cb284dff1d3c225bbdaba0901bb5 /arch/x86/include/asm/i387.h | |
| parent | e7a570ff7dff9af6e54ff5e580a61ec7652137a0 (diff) | |
| parent | 8a1ab3155c2ac7fbe5f2038d6e26efeb607a1498 (diff) | |
Merge branch 'disintegrate-asm-generic' of git://git.infradead.org/users/dhowells/linux-headers into asm-generic
Patches from David Howells <dhowells@redhat.com>:
This is to complete part of the UAPI disintegration for which the
preparatory patches were pulled recently.
Note that there are some fixup patches which are at the base of the
branch aimed at you, plus all arches get the asm-generic branch merged in too.
* 'disintegrate-asm-generic' of git://git.infradead.org/users/dhowells/linux-headers:
UAPI: (Scripted) Disintegrate include/asm-generic
UAPI: Fix conditional header installation handling (notably kvm_para.h on m68k)
c6x: remove c6x signal.h
UAPI: Split compound conditionals containing __KERNEL__ in Arm64
UAPI: Fix the guards on various asm/unistd.h files
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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 257d9cca214..ed8089d6909 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 |