powerpc/32: Don't save thread.regs on interrupt entry
authorChristophe Leroy <christophe.leroy@csgroup.eu>
Fri, 12 Mar 2021 12:50:35 +0000 (12:50 +0000)
committerMichael Ellerman <mpe@ellerman.id.au>
Mon, 29 Mar 2021 02:22:08 +0000 (13:22 +1100)
Since commit 06d67d54741a ("powerpc: make process.c suitable for both
32-bit and 64-bit"), thread.regs is set on task creation, no need to
set it again and again at each interrupt entry as it never change.

Suggested-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20d52c627303d63e461797df13e6890fc04017d0.1615552867.git.christophe.leroy@csgroup.eu
arch/powerpc/kernel/entry_32.S

index 79311d0..1e201fc 100644 (file)
@@ -97,10 +97,8 @@ transfer_to_handler:
        stw     r2,_XER(r11)
        mfspr   r12,SPRN_SPRG_THREAD
        tovirt(r12, r12)
-       beq     2f                      /* if from user, fix up THREAD.regs */
+       beq     2f
        addi    r2, r12, -THREAD
-       addi    r11,r1,STACK_FRAME_OVERHEAD
-       stw     r11,PT_REGS(r12)
 #ifdef CONFIG_PPC_BOOK3S_32
        kuep_lock r11, r12
 #endif
@@ -147,7 +145,6 @@ transfer_to_syscall:
        /* Calling convention has r9 = orig r0, r10 = regs */
        addi    r10,r1,STACK_FRAME_OVERHEAD
        mr      r9,r0
-       stw     r10,THREAD+PT_REGS(r2)
        bl      system_call_exception
 
 ret_from_syscall: