[RFC PATCH v1 25/41] powerpc/32: Set regs parameter in r3 in transfer_to_handler

From: Christophe Leroy
Date: Tue Feb 09 2021 - 05:12:39 EST


All exception handlers take regs as first parameter.

Instead of setting r3 just before each call to a handler, set
it in transfer_to_handler.

Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxxxxxx>
---
arch/powerpc/kernel/entry_32.S | 5 ++---
arch/powerpc/kernel/head_32.h | 2 --
arch/powerpc/kernel/head_40x.S | 7 -------
arch/powerpc/kernel/head_8xx.S | 3 ---
arch/powerpc/kernel/head_book3s_32.S | 9 ++-------
arch/powerpc/kernel/head_booke.h | 11 +----------
arch/powerpc/kernel/head_fsl_booke.S | 4 +---
7 files changed, 6 insertions(+), 35 deletions(-)

diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index 9a75ccb800e7..0b4fdc930aa5 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -87,6 +87,7 @@ _ASM_NOKPROBE_SYMBOL(transfer_to_handler_full)
.globl transfer_to_handler
transfer_to_handler:
SAVE_NVGPRS(r11)
+ addi r3,r1,STACK_FRAME_OVERHEAD
stw r2,GPR2(r11)
stw r12,_NIP(r11)
stw r9,_MSR(r11)
@@ -99,8 +100,7 @@ transfer_to_handler:
tovirt(r12, r12)
beq 2f /* if from user, fix up THREAD.regs */
addi r2, r12, -THREAD
- addi r11,r1,STACK_FRAME_OVERHEAD
- stw r11,PT_REGS(r12)
+ stw r3,PT_REGS(r12)
#ifdef CONFIG_PPC_BOOK3S_32
kuep_lock r11, r12
#endif
@@ -228,7 +228,6 @@ ret_from_kernel_thread:
*/
.globl handle_page_fault
handle_page_fault:
- addi r3,r1,STACK_FRAME_OVERHEAD
bl do_page_fault
cmpwi r3,0
beq+ ret_from_except
diff --git a/arch/powerpc/kernel/head_32.h b/arch/powerpc/kernel/head_32.h
index 087445e45489..4d638d760a96 100644
--- a/arch/powerpc/kernel/head_32.h
+++ b/arch/powerpc/kernel/head_32.h
@@ -183,7 +183,6 @@ _ASM_NOKPROBE_SYMBOL(\name\()_virt)
#define EXCEPTION(n, label, hdlr, xfer) \
START_EXCEPTION(n, label) \
EXCEPTION_PROLOG label; \
- addi r3,r1,STACK_FRAME_OVERHEAD; \
xfer(n, hdlr)

#define EXC_XFER_TEMPLATE(hdlr, trap, msr, tfer, ret) \
@@ -215,7 +214,6 @@ _ASM_NOKPROBE_SYMBOL(\name\()_virt)
lwz r1, emergency_ctx@l(r1)
addi r1, r1, THREAD_SIZE - INT_FRAME_SIZE
EXCEPTION_PROLOG_2 vmap_stack_overflow
- addi r3, r1, STACK_FRAME_OVERHEAD
EXC_XFER_STD(0, stack_overflow_exception)
.endm

diff --git a/arch/powerpc/kernel/head_40x.S b/arch/powerpc/kernel/head_40x.S
index 86883ccb3dc5..08563d4170c6 100644
--- a/arch/powerpc/kernel/head_40x.S
+++ b/arch/powerpc/kernel/head_40x.S
@@ -185,7 +185,6 @@ _ASM_NOKPROBE_SYMBOL(\name\()_virt)
#define CRITICAL_EXCEPTION(n, label, hdlr) \
START_EXCEPTION(n, label); \
CRITICAL_EXCEPTION_PROLOG label; \
- addi r3,r1,STACK_FRAME_OVERHEAD; \
EXC_XFER_TEMPLATE(hdlr, n+2, (MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)), \
crit_transfer_to_handler, ret_from_crit_exc)

@@ -227,13 +226,11 @@ _ASM_NOKPROBE_SYMBOL(\name\()_virt)
/* 0x0600 - Alignment Exception */
START_EXCEPTION(0x0600, Alignment)
EXCEPTION_PROLOG Alignment handle_dar_dsisr=1
- addi r3,r1,STACK_FRAME_OVERHEAD
EXC_XFER_STD(0x600, alignment_exception)

/* 0x0700 - Program Exception */
START_EXCEPTION(0x0700, ProgramCheck)
EXCEPTION_PROLOG ProgramCheck handle_dar_dsisr=1
- addi r3,r1,STACK_FRAME_OVERHEAD
EXC_XFER_STD(0x700, program_check_exception)

EXCEPTION(0x0800, Trap_08, unknown_exception, EXC_XFER_STD)
@@ -494,7 +491,6 @@ _ASM_NOKPROBE_SYMBOL(\name\()_virt)
/* continue normal handling for a critical exception... */
2: mfspr r4,SPRN_DBSR
stw r4,_ESR(r11) /* DebugException takes DBSR in _ESR */
- addi r3,r1,STACK_FRAME_OVERHEAD
EXC_XFER_TEMPLATE(DebugException, 0x2002, \
(MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)), \
crit_transfer_to_handler, ret_from_crit_exc)
@@ -505,21 +501,18 @@ Decrementer:
EXCEPTION_PROLOG Decrementer
lis r0,TSR_PIS@h
mtspr SPRN_TSR,r0 /* Clear the PIT exception */
- addi r3,r1,STACK_FRAME_OVERHEAD
EXC_XFER_LITE(0x1000, timer_interrupt)

/* Fixed Interval Timer (FIT) Exception. (from 0x1010) */
__HEAD
FITException:
EXCEPTION_PROLOG FITException
- addi r3,r1,STACK_FRAME_OVERHEAD;
EXC_XFER_STD(0x1010, unknown_exception)

/* Watchdog Timer (WDT) Exception. (from 0x1020) */
__HEAD
WDTException:
CRITICAL_EXCEPTION_PROLOG WDTException
- addi r3,r1,STACK_FRAME_OVERHEAD;
EXC_XFER_TEMPLATE(WatchdogException, 0x1020+2,
(MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)),
crit_transfer_to_handler, ret_from_crit_exc)
diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index 932702a38234..eb1d40a8f2c4 100644
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S
@@ -123,7 +123,6 @@ instruction_counter:
/* Machine check */
START_EXCEPTION(0x200, MachineCheck)
EXCEPTION_PROLOG MachineCheck handle_dar_dsisr=1
- addi r3,r1,STACK_FRAME_OVERHEAD
EXC_XFER_STD(0x200, machine_check_exception)

/* External interrupt */
@@ -132,7 +131,6 @@ instruction_counter:
/* Alignment exception */
START_EXCEPTION(0x600, Alignment)
EXCEPTION_PROLOG Alignment handle_dar_dsisr=1
- addi r3,r1,STACK_FRAME_OVERHEAD
EXC_XFER_STD(0x600, alignment_exception)

/* Program check exception */
@@ -348,7 +346,6 @@ DARFixed:/* Return from dcbx instruction bug workaround */

1: EXCEPTION_PROLOG_1
EXCEPTION_PROLOG_2 DataBreakpoint handle_dar_dsisr=1
- addi r3,r1,STACK_FRAME_OVERHEAD
mfspr r4,SPRN_BAR
stw r4,_DAR(r11)
EXC_XFER_STD(0x1c00, do_break)
diff --git a/arch/powerpc/kernel/head_book3s_32.S b/arch/powerpc/kernel/head_book3s_32.S
index 24cb245e1c5b..626e9fbac2cc 100644
--- a/arch/powerpc/kernel/head_book3s_32.S
+++ b/arch/powerpc/kernel/head_book3s_32.S
@@ -267,7 +267,6 @@ __secondary_hold_acknowledge:
#endif /* CONFIG_PPC_CHRP */
EXCEPTION_PROLOG_1
7: EXCEPTION_PROLOG_2 MachineCheck
- addi r3,r1,STACK_FRAME_OVERHEAD
#ifdef CONFIG_PPC_CHRP
beq cr1, 1f
twi 31, 0, 0
@@ -337,7 +336,6 @@ END_MMU_FTR_SECTION_IFSET(MMU_FTR_HPTE_TABLE)
/* Alignment exception */
START_EXCEPTION(0x600, Alignment)
EXCEPTION_PROLOG Alignment handle_dar_dsisr=1
- addi r3,r1,STACK_FRAME_OVERHEAD
EXC_XFER_STD(0x600, alignment_exception)

/* Program check exception */
@@ -357,8 +355,7 @@ END_FTR_SECTION_IFSET(CPU_FTR_FPU_UNAVAILABLE)
beq 1f
bl load_up_fpu /* if from user, just load it up */
b fast_exception_return
-1: addi r3,r1,STACK_FRAME_OVERHEAD
- EXC_XFER_LITE(0x800, kernel_fp_unavailable_exception)
+1: EXC_XFER_LITE(0x800, kernel_fp_unavailable_exception)
#else
b ProgramCheck
#endif
@@ -719,13 +716,11 @@ AltiVecUnavailable:
bl load_up_altivec /* if from user, just load it up */
b fast_exception_return
#endif /* CONFIG_ALTIVEC */
-1: addi r3,r1,STACK_FRAME_OVERHEAD
- EXC_XFER_LITE(0xf20, altivec_unavailable_exception)
+1: EXC_XFER_LITE(0xf20, altivec_unavailable_exception)

__HEAD
PerformanceMonitor:
EXCEPTION_PROLOG PerformanceMonitor
- addi r3,r1,STACK_FRAME_OVERHEAD
EXC_XFER_STD(0xf00, performance_monitor_exception)


diff --git a/arch/powerpc/kernel/head_booke.h b/arch/powerpc/kernel/head_booke.h
index c88c1c474381..740ddf506efc 100644
--- a/arch/powerpc/kernel/head_booke.h
+++ b/arch/powerpc/kernel/head_booke.h
@@ -294,13 +294,11 @@ ALT_FTR_SECTION_END_IFSET(CPU_FTR_EMB_HV)
#define EXCEPTION(n, intno, label, hdlr, xfer) \
START_EXCEPTION(label); \
NORMAL_EXCEPTION_PROLOG(intno); \
- addi r3,r1,STACK_FRAME_OVERHEAD; \
xfer(n, hdlr)

#define CRITICAL_EXCEPTION(n, intno, label, hdlr) \
START_EXCEPTION(label); \
CRITICAL_EXCEPTION_PROLOG(intno); \
- addi r3,r1,STACK_FRAME_OVERHEAD; \
SAVE_MMU_REGS; \
SAVE_xSRR SRR; \
EXC_XFER_TEMPLATE(hdlr, n+2, (MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)), \
@@ -311,7 +309,6 @@ ALT_FTR_SECTION_END_IFSET(CPU_FTR_EMB_HV)
MCHECK_EXCEPTION_PROLOG; \
mfspr r5,SPRN_ESR; \
stw r5,_ESR(r11); \
- addi r3,r1,STACK_FRAME_OVERHEAD; \
SAVE_xSRR DSRR; \
SAVE_xSRR CSRR; \
SAVE_MMU_REGS; \
@@ -398,7 +395,6 @@ ALT_FTR_SECTION_END_IFSET(CPU_FTR_EMB_HV)
/* continue normal handling for a debug exception... */ \
2: mfspr r4,SPRN_DBSR; \
stw r4,_ESR(r11); /* DebugException takes DBSR in _ESR */\
- addi r3,r1,STACK_FRAME_OVERHEAD; \
SAVE_xSRR CSRR; \
SAVE_MMU_REGS; \
SAVE_xSRR SRR; \
@@ -455,7 +451,6 @@ ALT_FTR_SECTION_END_IFSET(CPU_FTR_EMB_HV)
/* continue normal handling for a critical exception... */ \
2: mfspr r4,SPRN_DBSR; \
stw r4,_ESR(r11); /* DebugException takes DBSR in _ESR */\
- addi r3,r1,STACK_FRAME_OVERHEAD; \
SAVE_MMU_REGS; \
SAVE_xSRR SRR; \
EXC_XFER_TEMPLATE(DebugException, 0x2002, (MSR_KERNEL & ~(MSR_ME|MSR_DE|MSR_CE)), crit_transfer_to_handler, ret_from_crit_exc)
@@ -482,7 +477,6 @@ ALT_FTR_SECTION_END_IFSET(CPU_FTR_EMB_HV)
NORMAL_EXCEPTION_PROLOG(ALIGNMENT); \
mfspr r4,SPRN_DEAR; /* Grab the DEAR and save it */ \
stw r4,_DEAR(r11); \
- addi r3,r1,STACK_FRAME_OVERHEAD; \
EXC_XFER_STD(0x0600, alignment_exception)

#define PROGRAM_EXCEPTION \
@@ -490,7 +484,6 @@ ALT_FTR_SECTION_END_IFSET(CPU_FTR_EMB_HV)
NORMAL_EXCEPTION_PROLOG(PROGRAM); \
mfspr r4,SPRN_ESR; /* Grab the ESR and save it */ \
stw r4,_ESR(r11); \
- addi r3,r1,STACK_FRAME_OVERHEAD; \
EXC_XFER_STD(0x0700, program_check_exception)

#define DECREMENTER_EXCEPTION \
@@ -498,7 +491,6 @@ ALT_FTR_SECTION_END_IFSET(CPU_FTR_EMB_HV)
NORMAL_EXCEPTION_PROLOG(DECREMENTER); \
lis r0,TSR_DIS@h; /* Setup the DEC interrupt mask */ \
mtspr SPRN_TSR,r0; /* Clear the DEC interrupt */ \
- addi r3,r1,STACK_FRAME_OVERHEAD; \
EXC_XFER_LITE(0x0900, timer_interrupt)

#define FP_UNAVAILABLE_EXCEPTION \
@@ -507,8 +499,7 @@ ALT_FTR_SECTION_END_IFSET(CPU_FTR_EMB_HV)
beq 1f; \
bl load_up_fpu; /* if from user, just load it up */ \
b fast_exception_return; \
-1: addi r3,r1,STACK_FRAME_OVERHEAD; \
- EXC_XFER_STD(0x800, kernel_fp_unavailable_exception)
+1: EXC_XFER_STD(0x800, kernel_fp_unavailable_exception)

#else /* __ASSEMBLY__ */
struct exception_regs {
diff --git a/arch/powerpc/kernel/head_fsl_booke.S b/arch/powerpc/kernel/head_fsl_booke.S
index 3f4a40cccef5..f51c66f747ad 100644
--- a/arch/powerpc/kernel/head_fsl_booke.S
+++ b/arch/powerpc/kernel/head_fsl_booke.S
@@ -372,7 +372,6 @@ interrupt_base:
bne 1f
EXC_XFER_LITE(0x0300, handle_page_fault)
1:
- addi r3,r1,STACK_FRAME_OVERHEAD
EXC_XFER_LITE(0x0300, CacheLockingException)

/* Instruction Storage Interrupt */
@@ -618,8 +617,7 @@ END_BTB_FLUSH_SECTION
beq 1f
bl load_up_spe
b fast_exception_return
-1: addi r3,r1,STACK_FRAME_OVERHEAD
- EXC_XFER_LITE(0x2010, KernelSPE)
+1: EXC_XFER_LITE(0x2010, KernelSPE)
#elif defined(CONFIG_SPE_POSSIBLE)
EXCEPTION(0x2020, SPE_UNAVAIL, SPEUnavailable, \
unknown_exception, EXC_XFER_STD)
--
2.25.0