riscv: fpu: drop SR_SD bit checking

SR_SD summarizes the dirty status of FS/VS/XS. However, the current code
structure does not fully utilize it because each extension specific code
is divided into an individual segment. So remove the SR_SD check for
now.

Signed-off-by: Andy Chiu <andy.chiu@sifive.com>
Reviewed-by: Song Shuai <songshuaishuai@tinylab.org>
Reviewed-by: Guo Ren <guoren@kernel.org>
Tested-by: Björn Töpel <bjorn@rivosinc.com>
Tested-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@bp.renesas.com>
Link: https://lore.kernel.org/r/20240115055929.4736-7-andy.chiu@sifive.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>

diff --git a/arch/riscv/include/asm/switch_to.h b/arch/riscv/include/asm/switch_to.h
index f90d8e42f3c7911908ec1f5f19929ab5ba67ff3a..7efdb0584d47ac9887126a00dcfcc045619b27b5 100644 (file)
--- a/arch/riscv/include/asm/switch_to.h
+++ b/arch/riscv/include/asm/switch_to.h
@@ -53,8 +53,7 @@ static inline void __switch_to_fpu(struct task_struct *prev,
        struct pt_regs *regs;
 
        regs = task_pt_regs(prev);
-       if (unlikely(regs->status & SR_SD))
-               fstate_save(prev, regs);
+       fstate_save(prev, regs);
        fstate_restore(next, task_pt_regs(next));
 }