[PATCH v4 04/20] powerpc/8xx: Use patch_site for perf counters setup

From: Christophe Leroy
Date: Tue Sep 18 2018 - 12:57:16 EST


The 8xx TLB miss routines are patched when (de)activating
perf counters.

This patch uses the new patch_site functionality in order
to get a better code readability and avoid a label mess when
dumping the code with 'objdump -d'

Signed-off-by: Christophe Leroy <christophe.leroy@xxxxxx>
---
arch/powerpc/include/asm/mmu-8xx.h | 4 ++++
arch/powerpc/kernel/head_8xx.S | 33 +++++++++++++++++++--------------
arch/powerpc/perf/8xx-pmu.c | 27 ++++++++++++---------------
3 files changed, 35 insertions(+), 29 deletions(-)

diff --git a/arch/powerpc/include/asm/mmu-8xx.h b/arch/powerpc/include/asm/mmu-8xx.h
index 3a15d6647d47..fa05aa566ece 100644
--- a/arch/powerpc/include/asm/mmu-8xx.h
+++ b/arch/powerpc/include/asm/mmu-8xx.h
@@ -234,6 +234,10 @@ extern s32 patch__itlbmiss_linmem_top;
extern s32 patch__dtlbmiss_linmem_top, patch__dtlbmiss_immr_jmp;
extern s32 patch__fixupdar_linmem_top;

+extern s32 patch__itlbmiss_exit_1, patch__itlbmiss_exit_2;
+extern s32 patch__dtlbmiss_exit_1, patch__dtlbmiss_exit_2, patch__dtlbmiss_exit_3;
+extern s32 patch__itlbmiss_perf, patch__dtlbmiss_perf;
+
#endif /* !__ASSEMBLY__ */

#if defined(CONFIG_PPC_4K_PAGES)
diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S
index 0425571a533d..3b67b9533c82 100644
--- a/arch/powerpc/kernel/head_8xx.S
+++ b/arch/powerpc/kernel/head_8xx.S
@@ -374,16 +374,17 @@ InstructionTLBMiss:
mtspr SPRN_MI_RPN, r10 /* Update TLB entry */

/* Restore registers */
-_ENTRY(itlb_miss_exit_1)
- mfspr r10, SPRN_SPRG_SCRATCH0
+0: mfspr r10, SPRN_SPRG_SCRATCH0
mfspr r11, SPRN_SPRG_SCRATCH1
#if defined(ITLB_MISS_KERNEL) || defined(CONFIG_HUGETLB_PAGE)
mfspr r12, SPRN_SPRG_SCRATCH2
#endif
rfi
+ patch_site 0b, patch__itlbmiss_exit_1
+
#ifdef CONFIG_PERF_EVENTS
-_ENTRY(itlb_miss_perf)
- lis r10, (itlb_miss_counter - PAGE_OFFSET)@ha
+ patch_site 0f, patch__itlbmiss_perf
+0: lis r10, (itlb_miss_counter - PAGE_OFFSET)@ha
lwz r11, (itlb_miss_counter - PAGE_OFFSET)@l(r10)
addi r11, r11, 1
stw r11, (itlb_miss_counter - PAGE_OFFSET)@l(r10)
@@ -499,14 +500,16 @@ DataStoreTLBMiss:

/* Restore registers */
mtspr SPRN_DAR, r11 /* Tag DAR */
-_ENTRY(dtlb_miss_exit_1)
- mfspr r10, SPRN_SPRG_SCRATCH0
+
+0: mfspr r10, SPRN_SPRG_SCRATCH0
mfspr r11, SPRN_SPRG_SCRATCH1
mfspr r12, SPRN_SPRG_SCRATCH2
rfi
+ patch_site 0b, patch__dtlbmiss_exit_1
+
#ifdef CONFIG_PERF_EVENTS
-_ENTRY(dtlb_miss_perf)
- lis r10, (dtlb_miss_counter - PAGE_OFFSET)@ha
+ patch_site 0f, patch__dtlbmiss_perf
+0: lis r10, (dtlb_miss_counter - PAGE_OFFSET)@ha
lwz r11, (dtlb_miss_counter - PAGE_OFFSET)@l(r10)
addi r11, r11, 1
stw r11, (dtlb_miss_counter - PAGE_OFFSET)@l(r10)
@@ -658,11 +661,12 @@ DTLBMissIMMR:

li r11, RPN_PATTERN
mtspr SPRN_DAR, r11 /* Tag DAR */
-_ENTRY(dtlb_miss_exit_2)
- mfspr r10, SPRN_SPRG_SCRATCH0
+
+0: mfspr r10, SPRN_SPRG_SCRATCH0
mfspr r11, SPRN_SPRG_SCRATCH1
mfspr r12, SPRN_SPRG_SCRATCH2
rfi
+ patch_site 0b, patch__dtlbmiss_exit_2

DTLBMissLinear:
mtcr r12
@@ -676,11 +680,12 @@ DTLBMissLinear:

li r11, RPN_PATTERN
mtspr SPRN_DAR, r11 /* Tag DAR */
-_ENTRY(dtlb_miss_exit_3)
- mfspr r10, SPRN_SPRG_SCRATCH0
+
+0: mfspr r10, SPRN_SPRG_SCRATCH0
mfspr r11, SPRN_SPRG_SCRATCH1
mfspr r12, SPRN_SPRG_SCRATCH2
rfi
+ patch_site 0b, patch__dtlbmiss_exit_3

#ifndef CONFIG_PIN_TLB_TEXT
ITLBMissLinear:
@@ -693,11 +698,11 @@ ITLBMissLinear:
_PAGE_PRESENT
mtspr SPRN_MI_RPN, r10 /* Update TLB entry */

-_ENTRY(itlb_miss_exit_2)
- mfspr r10, SPRN_SPRG_SCRATCH0
+0: mfspr r10, SPRN_SPRG_SCRATCH0
mfspr r11, SPRN_SPRG_SCRATCH1
mfspr r12, SPRN_SPRG_SCRATCH2
rfi
+ patch_site 0b, patch__itlbmiss_exit_2
#endif

/* This is the procedure to calculate the data EA for buggy dcbx,dcbi instructions
diff --git a/arch/powerpc/perf/8xx-pmu.c b/arch/powerpc/perf/8xx-pmu.c
index 6c0020d1c561..808f1873de61 100644
--- a/arch/powerpc/perf/8xx-pmu.c
+++ b/arch/powerpc/perf/8xx-pmu.c
@@ -31,9 +31,6 @@

extern unsigned long itlb_miss_counter, dtlb_miss_counter;
extern atomic_t instruction_counter;
-extern unsigned int itlb_miss_perf, dtlb_miss_perf;
-extern unsigned int itlb_miss_exit_1, itlb_miss_exit_2;
-extern unsigned int dtlb_miss_exit_1, dtlb_miss_exit_2, dtlb_miss_exit_3;

static atomic_t insn_ctr_ref;
static atomic_t itlb_miss_ref;
@@ -103,22 +100,22 @@ static int mpc8xx_pmu_add(struct perf_event *event, int flags)
break;
case PERF_8xx_ID_ITLB_LOAD_MISS:
if (atomic_inc_return(&itlb_miss_ref) == 1) {
- unsigned long target = (unsigned long)&itlb_miss_perf;
+ unsigned long target = site_addr(&patch__itlbmiss_perf);

- patch_branch(&itlb_miss_exit_1, target, 0);
+ patch_branch_site(&patch__itlbmiss_exit_1, target, 0);
#ifndef CONFIG_PIN_TLB_TEXT
- patch_branch(&itlb_miss_exit_2, target, 0);
+ patch_branch_site(&patch__itlbmiss_exit_2, target, 0);
#endif
}
val = itlb_miss_counter;
break;
case PERF_8xx_ID_DTLB_LOAD_MISS:
if (atomic_inc_return(&dtlb_miss_ref) == 1) {
- unsigned long target = (unsigned long)&dtlb_miss_perf;
+ unsigned long target = site_addr(&patch__dtlbmiss_perf);

- patch_branch(&dtlb_miss_exit_1, target, 0);
- patch_branch(&dtlb_miss_exit_2, target, 0);
- patch_branch(&dtlb_miss_exit_3, target, 0);
+ patch_branch_site(&patch__dtlbmiss_exit_1, target, 0);
+ patch_branch_site(&patch__dtlbmiss_exit_2, target, 0);
+ patch_branch_site(&patch__dtlbmiss_exit_3, target, 0);
}
val = dtlb_miss_counter;
break;
@@ -180,17 +177,17 @@ static void mpc8xx_pmu_del(struct perf_event *event, int flags)
break;
case PERF_8xx_ID_ITLB_LOAD_MISS:
if (atomic_dec_return(&itlb_miss_ref) == 0) {
- patch_instruction(&itlb_miss_exit_1, insn);
+ patch_instruction_site(&patch__itlbmiss_exit_1, insn);
#ifndef CONFIG_PIN_TLB_TEXT
- patch_instruction(&itlb_miss_exit_2, insn);
+ patch_instruction_site(&patch__itlbmiss_exit_2, insn);
#endif
}
break;
case PERF_8xx_ID_DTLB_LOAD_MISS:
if (atomic_dec_return(&dtlb_miss_ref) == 0) {
- patch_instruction(&dtlb_miss_exit_1, insn);
- patch_instruction(&dtlb_miss_exit_2, insn);
- patch_instruction(&dtlb_miss_exit_3, insn);
+ patch_instruction_site(&patch__dtlbmiss_exit_1, insn);
+ patch_instruction_site(&patch__dtlbmiss_exit_2, insn);
+ patch_instruction_site(&patch__dtlbmiss_exit_3, insn);
}
break;
}
--
2.13.3