x86/fpu: Decouple fpregs_activate()/fpregs_deactivate() from fpu->fpregs_active
authorIngo Molnar <mingo@kernel.org>
Sat, 23 Sep 2017 13:00:02 +0000 (15:00 +0200)
committerIngo Molnar <mingo@kernel.org>
Sun, 24 Sep 2017 11:04:34 +0000 (13:04 +0200)
commit6cf4edbe0526db311a28734609da888fdfcb3604
treeae414faeb5a0e91376697a3b54719cc74374dc43
parentf1c8cd0176078c7bcafdc89cac447cab672a0b5e
x86/fpu: Decouple fpregs_activate()/fpregs_deactivate() from fpu->fpregs_active

The fpregs_activate()/fpregs_deactivate() are currently called in such a pattern:

if (!fpu->fpregs_active)
fpregs_activate(fpu);

...

if (fpu->fpregs_active)
fpregs_deactivate(fpu);

But note that it's actually safe to call them without checking the flag first.

This further decouples the fpu->fpregs_active flag from actual FPU logic.

Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yu-cheng Yu <yu-cheng.yu@intel.com>
Link: http://lkml.kernel.org/r/20170923130016.21448-20-mingo@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
arch/x86/include/asm/fpu/internal.h
arch/x86/kernel/fpu/core.c