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Message-Id: <20220925175356.681-5-jszhang@kernel.org>
Date: Mon, 26 Sep 2022 01:53:56 +0800
From: Jisheng Zhang <jszhang@...nel.org>
To: Paul Walmsley <paul.walmsley@...ive.com>,
Palmer Dabbelt <palmer@...belt.com>,
Albert Ou <aou@...s.berkeley.edu>, Guo Ren <guoren@...nel.org>,
Nathan Chancellor <nathan@...nel.org>,
Nick Desaulniers <ndesaulniers@...gle.com>
Cc: linux-riscv@...ts.infradead.org, linux-kernel@...r.kernel.org,
llvm@...ts.linux.dev
Subject: [PATCH 4/4] riscv: entry: consolidate general regs saving into save_gp
Consolidate the saving GPs(except sp and tp into save_gp macro.
No functional change.
Signed-off-by: Jisheng Zhang <jszhang@...nel.org>
---
arch/riscv/kernel/entry.S | 85 ++++++++++++++-------------------------
1 file changed, 31 insertions(+), 54 deletions(-)
diff --git a/arch/riscv/kernel/entry.S b/arch/riscv/kernel/entry.S
index 442d93beffcf..04e11d257ad6 100644
--- a/arch/riscv/kernel/entry.S
+++ b/arch/riscv/kernel/entry.S
@@ -14,31 +14,8 @@
#include <asm/asm-offsets.h>
#include <asm/errata_list.h>
-ENTRY(handle_exception)
- /*
- * If coming from userspace, preserve the user thread pointer and load
- * the kernel thread pointer. If we came from the kernel, the scratch
- * register will contain 0, and we should continue on the current TP.
- */
- csrrw tp, CSR_SCRATCH, tp
- bnez tp, _save_context
-
-_restore_kernel_tpsp:
- csrr tp, CSR_SCRATCH
- REG_S sp, TASK_TI_KERNEL_SP(tp)
-
-#ifdef CONFIG_VMAP_STACK
- addi sp, sp, -(PT_SIZE_ON_STACK)
- srli sp, sp, THREAD_SHIFT
- andi sp, sp, 0x1
- bnez sp, handle_kernel_stack_overflow
- REG_L sp, TASK_TI_KERNEL_SP(tp)
-#endif
-
-_save_context:
- REG_S sp, TASK_TI_USER_SP(tp)
- REG_L sp, TASK_TI_KERNEL_SP(tp)
- addi sp, sp, -(PT_SIZE_ON_STACK)
+ /* save all GPs except sp and tp */
+ .macro save_gp
REG_S x1, PT_RA(sp)
REG_S x3, PT_GP(sp)
REG_S x5, PT_T0(sp)
@@ -68,6 +45,34 @@ _save_context:
REG_S x29, PT_T4(sp)
REG_S x30, PT_T5(sp)
REG_S x31, PT_T6(sp)
+ .endm
+
+ENTRY(handle_exception)
+ /*
+ * If coming from userspace, preserve the user thread pointer and load
+ * the kernel thread pointer. If we came from the kernel, the scratch
+ * register will contain 0, and we should continue on the current TP.
+ */
+ csrrw tp, CSR_SCRATCH, tp
+ bnez tp, _save_context
+
+_restore_kernel_tpsp:
+ csrr tp, CSR_SCRATCH
+ REG_S sp, TASK_TI_KERNEL_SP(tp)
+
+#ifdef CONFIG_VMAP_STACK
+ addi sp, sp, -(PT_SIZE_ON_STACK)
+ srli sp, sp, THREAD_SHIFT
+ andi sp, sp, 0x1
+ bnez sp, handle_kernel_stack_overflow
+ REG_L sp, TASK_TI_KERNEL_SP(tp)
+#endif
+
+_save_context:
+ REG_S sp, TASK_TI_USER_SP(tp)
+ REG_L sp, TASK_TI_KERNEL_SP(tp)
+ addi sp, sp, -(PT_SIZE_ON_STACK)
+ save_gp
/*
* Disable user-mode memory access as it should only be set in the
@@ -234,35 +239,7 @@ ENTRY(handle_kernel_stack_overflow)
addi sp, sp, -(PT_SIZE_ON_STACK)
//save context to overflow stack
- REG_S x1, PT_RA(sp)
- REG_S x3, PT_GP(sp)
- REG_S x5, PT_T0(sp)
- REG_S x6, PT_T1(sp)
- REG_S x7, PT_T2(sp)
- REG_S x8, PT_S0(sp)
- REG_S x9, PT_S1(sp)
- REG_S x10, PT_A0(sp)
- REG_S x11, PT_A1(sp)
- REG_S x12, PT_A2(sp)
- REG_S x13, PT_A3(sp)
- REG_S x14, PT_A4(sp)
- REG_S x15, PT_A5(sp)
- REG_S x16, PT_A6(sp)
- REG_S x17, PT_A7(sp)
- REG_S x18, PT_S2(sp)
- REG_S x19, PT_S3(sp)
- REG_S x20, PT_S4(sp)
- REG_S x21, PT_S5(sp)
- REG_S x22, PT_S6(sp)
- REG_S x23, PT_S7(sp)
- REG_S x24, PT_S8(sp)
- REG_S x25, PT_S9(sp)
- REG_S x26, PT_S10(sp)
- REG_S x27, PT_S11(sp)
- REG_S x28, PT_T3(sp)
- REG_S x29, PT_T4(sp)
- REG_S x30, PT_T5(sp)
- REG_S x31, PT_T6(sp)
+ save_gp
REG_L s0, TASK_TI_KERNEL_SP(tp)
csrr s1, CSR_STATUS
--
2.34.1
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