Instead of open-coded in_kernel_fpu access, Use kernel_fpu_disabled() in interrupted_kernel_fpu_idle(), matching the other kernel_fpu_*() methods.
Also add some documentation for in_kernel_fpu. Reviewed-by: Borislav Petkov <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Fenghua Yu <[email protected]> Cc: H. Peter Anvin <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Oleg Nesterov <[email protected]> Cc: Thomas Gleixner <[email protected]> Signed-off-by: Ingo Molnar <[email protected]> --- arch/x86/kernel/fpu/core.c | 18 +++++++++++++++++- 1 file changed, 17 insertions(+), 1 deletion(-) diff --git a/arch/x86/kernel/fpu/core.c b/arch/x86/kernel/fpu/core.c index bcf705751d02..87f10b49da47 100644 --- a/arch/x86/kernel/fpu/core.c +++ b/arch/x86/kernel/fpu/core.c @@ -7,6 +7,17 @@ */ #include <asm/fpu-internal.h> +/* + * Track whether the kernel is using the FPU state + * currently. + * + * This flag is used: + * + * - by IRQ context code to potentially use the FPU + * if it's unused. + * + * - to debug kernel_fpu_begin()/end() correctness + */ static DEFINE_PER_CPU(bool, in_kernel_fpu); static void kernel_fpu_disable(void) @@ -21,6 +32,11 @@ static void kernel_fpu_enable(void) this_cpu_write(in_kernel_fpu, false); } +static bool kernel_fpu_disabled(void) +{ + return this_cpu_read(in_kernel_fpu); +} + /* * Were we in an interrupt that interrupted kernel mode? * @@ -35,7 +51,7 @@ static void kernel_fpu_enable(void) */ static bool interrupted_kernel_fpu_idle(void) { - if (this_cpu_read(in_kernel_fpu)) + if (kernel_fpu_disabled()) return false; if (use_eager_fpu()) -- 2.1.0 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
