x86, fpu: lazy allocation of FPU area - v5
Only allocate the FPU area when the application actually uses FPU, i.e., in the
first lazy FPU trap. This could save memory for non-fpu using apps.
for example: on my system after boot, there are around 300 processes, with
only 17 using FPU.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/include/asm-x86/i387.h b/include/asm-x86/i387.h
index 382a5fa..4be7b58 100644
--- a/include/asm-x86/i387.h
+++ b/include/asm-x86/i387.h
@@ -21,7 +21,7 @@
extern void fpu_init(void);
extern void mxcsr_feature_mask_init(void);
-extern void init_fpu(struct task_struct *child);
+extern int init_fpu(struct task_struct *child);
extern asmlinkage void math_state_restore(void);
extern void init_thread_xstate(void);