[PATCH v1] LoongArch: Use SYM_CODE to annotate exception handlers

From: Tiezhu Yang
Date: Mon Oct 16 2023 - 05:38:07 EST


As described in include/linux/linkage.h,

FUNC -- C-like functions (proper stack frame etc.)
CODE -- non-C code (e.g. irq handlers with different, special stack etc.)

SYM_FUNC_START -- use for global functions
SYM_CODE_START -- use for non-C (special) functions

use SYM_CODE to annotate exception handlers.

Signed-off-by: Tiezhu Yang <yangtiezhu@xxxxxxxxxxx>
---
arch/loongarch/include/asm/linkage.h | 8 ++++++++
arch/loongarch/kernel/entry.S | 4 ++--
arch/loongarch/kernel/genex.S | 16 ++++++++--------
arch/loongarch/mm/tlbex.S | 36 ++++++++++++++++++------------------
4 files changed, 36 insertions(+), 28 deletions(-)

diff --git a/arch/loongarch/include/asm/linkage.h b/arch/loongarch/include/asm/linkage.h
index 81b0c4c..e2eca1a 100644
--- a/arch/loongarch/include/asm/linkage.h
+++ b/arch/loongarch/include/asm/linkage.h
@@ -33,4 +33,12 @@
.cfi_endproc; \
SYM_END(name, SYM_T_FUNC)

+#define SYM_CODE_START(name) \
+ SYM_START(name, SYM_L_GLOBAL, SYM_A_ALIGN) \
+ .cfi_startproc;
+
+#define SYM_CODE_END(name) \
+ .cfi_endproc; \
+ SYM_END(name, SYM_T_NONE)
+
#endif
diff --git a/arch/loongarch/kernel/entry.S b/arch/loongarch/kernel/entry.S
index 65518bb..1ec8e4c 100644
--- a/arch/loongarch/kernel/entry.S
+++ b/arch/loongarch/kernel/entry.S
@@ -18,7 +18,7 @@
.text
.cfi_sections .debug_frame
.align 5
-SYM_FUNC_START(handle_syscall)
+SYM_CODE_START(handle_syscall)
csrrd t0, PERCPU_BASE_KS
la.pcrel t1, kernelsp
add.d t1, t1, t0
@@ -71,7 +71,7 @@ SYM_FUNC_START(handle_syscall)
bl do_syscall

RESTORE_ALL_AND_RET
-SYM_FUNC_END(handle_syscall)
+SYM_CODE_END(handle_syscall)
_ASM_NOKPROBE(handle_syscall)

SYM_CODE_START(ret_from_fork)
diff --git a/arch/loongarch/kernel/genex.S b/arch/loongarch/kernel/genex.S
index 78f0663..2bb3aa2 100644
--- a/arch/loongarch/kernel/genex.S
+++ b/arch/loongarch/kernel/genex.S
@@ -31,7 +31,7 @@ SYM_FUNC_START(__arch_cpu_idle)
1: jr ra
SYM_FUNC_END(__arch_cpu_idle)

-SYM_FUNC_START(handle_vint)
+SYM_CODE_START(handle_vint)
BACKUP_T0T1
SAVE_ALL
la_abs t1, __arch_cpu_idle
@@ -46,11 +46,11 @@ SYM_FUNC_START(handle_vint)
la_abs t0, do_vint
jirl ra, t0, 0
RESTORE_ALL_AND_RET
-SYM_FUNC_END(handle_vint)
+SYM_CODE_END(handle_vint)

-SYM_FUNC_START(except_vec_cex)
+SYM_CODE_START(except_vec_cex)
b cache_parity_error
-SYM_FUNC_END(except_vec_cex)
+SYM_CODE_END(except_vec_cex)

.macro build_prep_badv
csrrd t0, LOONGARCH_CSR_BADV
@@ -66,7 +66,7 @@ SYM_FUNC_END(except_vec_cex)

.macro BUILD_HANDLER exception handler prep
.align 5
- SYM_FUNC_START(handle_\exception)
+ SYM_CODE_START(handle_\exception)
666:
BACKUP_T0T1
SAVE_ALL
@@ -76,7 +76,7 @@ SYM_FUNC_END(except_vec_cex)
jirl ra, t0, 0
668:
RESTORE_ALL_AND_RET
- SYM_FUNC_END(handle_\exception)
+ SYM_CODE_END(handle_\exception)
SYM_DATA(unwind_hint_\exception, .word 668b - 666b)
.endm

@@ -93,7 +93,7 @@ SYM_FUNC_END(except_vec_cex)
BUILD_HANDLER watch watch none
BUILD_HANDLER reserved reserved none /* others */

-SYM_FUNC_START(handle_sys)
+SYM_CODE_START(handle_sys)
la_abs t0, handle_syscall
jr t0
-SYM_FUNC_END(handle_sys)
+SYM_CODE_END(handle_sys)
diff --git a/arch/loongarch/mm/tlbex.S b/arch/loongarch/mm/tlbex.S
index ca17dd3..d5d682f 100644
--- a/arch/loongarch/mm/tlbex.S
+++ b/arch/loongarch/mm/tlbex.S
@@ -17,7 +17,7 @@
#define PTRS_PER_PTE_BITS (PAGE_SHIFT - 3)

.macro tlb_do_page_fault, write
- SYM_FUNC_START(tlb_do_page_fault_\write)
+ SYM_CODE_START(tlb_do_page_fault_\write)
SAVE_ALL
csrrd a2, LOONGARCH_CSR_BADV
move a0, sp
@@ -25,13 +25,13 @@
li.w a1, \write
bl do_page_fault
RESTORE_ALL_AND_RET
- SYM_FUNC_END(tlb_do_page_fault_\write)
+ SYM_CODE_END(tlb_do_page_fault_\write)
.endm

tlb_do_page_fault 0
tlb_do_page_fault 1

-SYM_FUNC_START(handle_tlb_protect)
+SYM_CODE_START(handle_tlb_protect)
BACKUP_T0T1
SAVE_ALL
move a0, sp
@@ -41,9 +41,9 @@ SYM_FUNC_START(handle_tlb_protect)
la_abs t0, do_page_fault
jirl ra, t0, 0
RESTORE_ALL_AND_RET
-SYM_FUNC_END(handle_tlb_protect)
+SYM_CODE_END(handle_tlb_protect)

-SYM_FUNC_START(handle_tlb_load)
+SYM_CODE_START(handle_tlb_load)
csrwr t0, EXCEPTION_KS0
csrwr t1, EXCEPTION_KS1
csrwr ra, EXCEPTION_KS2
@@ -187,16 +187,16 @@ nopage_tlb_load:
csrrd ra, EXCEPTION_KS2
la_abs t0, tlb_do_page_fault_0
jr t0
-SYM_FUNC_END(handle_tlb_load)
+SYM_CODE_END(handle_tlb_load)

-SYM_FUNC_START(handle_tlb_load_ptw)
+SYM_CODE_START(handle_tlb_load_ptw)
csrwr t0, LOONGARCH_CSR_KS0
csrwr t1, LOONGARCH_CSR_KS1
la_abs t0, tlb_do_page_fault_0
jr t0
-SYM_FUNC_END(handle_tlb_load_ptw)
+SYM_CODE_END(handle_tlb_load_ptw)

-SYM_FUNC_START(handle_tlb_store)
+SYM_CODE_START(handle_tlb_store)
csrwr t0, EXCEPTION_KS0
csrwr t1, EXCEPTION_KS1
csrwr ra, EXCEPTION_KS2
@@ -343,16 +343,16 @@ nopage_tlb_store:
csrrd ra, EXCEPTION_KS2
la_abs t0, tlb_do_page_fault_1
jr t0
-SYM_FUNC_END(handle_tlb_store)
+SYM_CODE_END(handle_tlb_store)

-SYM_FUNC_START(handle_tlb_store_ptw)
+SYM_CODE_START(handle_tlb_store_ptw)
csrwr t0, LOONGARCH_CSR_KS0
csrwr t1, LOONGARCH_CSR_KS1
la_abs t0, tlb_do_page_fault_1
jr t0
-SYM_FUNC_END(handle_tlb_store_ptw)
+SYM_CODE_END(handle_tlb_store_ptw)

-SYM_FUNC_START(handle_tlb_modify)
+SYM_CODE_START(handle_tlb_modify)
csrwr t0, EXCEPTION_KS0
csrwr t1, EXCEPTION_KS1
csrwr ra, EXCEPTION_KS2
@@ -497,16 +497,16 @@ nopage_tlb_modify:
csrrd ra, EXCEPTION_KS2
la_abs t0, tlb_do_page_fault_1
jr t0
-SYM_FUNC_END(handle_tlb_modify)
+SYM_CODE_END(handle_tlb_modify)

-SYM_FUNC_START(handle_tlb_modify_ptw)
+SYM_CODE_START(handle_tlb_modify_ptw)
csrwr t0, LOONGARCH_CSR_KS0
csrwr t1, LOONGARCH_CSR_KS1
la_abs t0, tlb_do_page_fault_1
jr t0
-SYM_FUNC_END(handle_tlb_modify_ptw)
+SYM_CODE_END(handle_tlb_modify_ptw)

-SYM_FUNC_START(handle_tlb_refill)
+SYM_CODE_START(handle_tlb_refill)
csrwr t0, LOONGARCH_CSR_TLBRSAVE
csrrd t0, LOONGARCH_CSR_PGD
lddir t0, t0, 3
@@ -521,4 +521,4 @@ SYM_FUNC_START(handle_tlb_refill)
tlbfill
csrrd t0, LOONGARCH_CSR_TLBRSAVE
ertn
-SYM_FUNC_END(handle_tlb_refill)
+SYM_CODE_END(handle_tlb_refill)
--
2.1.0