MIPS: Tidy up FPU context switching
Rather than saving the scalar FP or vector context in the assembly
resume function, reuse the existing C code we have in fpu.h to do
exactly that. This reduces duplication, results in a much easier to read
resume function & should allow the compiler to optimise out more MSA
code due to is_msa_enabled()/cpu_has_msa being known-zero at compile
time for kernels without MSA support.
Signed-off-by: Paul Burton <paul.burton@imgtec.com>
Cc: linux-mips@linux-mips.org
Cc: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Cc: Maciej W. Rozycki <macro@linux-mips.org>
Cc: linux-kernel@vger.kernel.org
Cc: James Hogan <james.hogan@imgtec.com>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: Manuel Lauss <manuel.lauss@gmail.com>
Patchwork: https://patchwork.linux-mips.org/patch/10830/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/include/asm/fpu.h b/arch/mips/include/asm/fpu.h
index 1b06251..9cbf383 100644
--- a/arch/mips/include/asm/fpu.h
+++ b/arch/mips/include/asm/fpu.h
@@ -164,25 +164,30 @@
return ret;
}
-static inline void lose_fpu(int save)
+static inline void lose_fpu_inatomic(int save, struct task_struct *tsk)
{
- preempt_disable();
if (is_msa_enabled()) {
if (save) {
- save_msa(current);
- current->thread.fpu.fcr31 =
+ save_msa(tsk);
+ tsk->thread.fpu.fcr31 =
read_32bit_cp1_register(CP1_STATUS);
}
disable_msa();
- clear_thread_flag(TIF_USEDMSA);
+ clear_tsk_thread_flag(tsk, TIF_USEDMSA);
__disable_fpu();
} else if (is_fpu_owner()) {
if (save)
- _save_fp(current);
+ _save_fp(tsk);
__disable_fpu();
}
- KSTK_STATUS(current) &= ~ST0_CU1;
- clear_thread_flag(TIF_USEDFPU);
+ KSTK_STATUS(tsk) &= ~ST0_CU1;
+ clear_tsk_thread_flag(tsk, TIF_USEDFPU);
+}
+
+static inline void lose_fpu(int save)
+{
+ preempt_disable();
+ lose_fpu_inatomic(save, current);
preempt_enable();
}