Currently, clear_page()/copy_page() are generated by Micro-assembler
dynamically. But they are unavailable until uasm_resolve_relocs() has
finished because jump labels are illegal before that. Since these
functions are shared by every CPU, we only call build_clear_page()/
build_copy_page() only once at boot time. Without this patch, programs
will get random memory corruption (segmentation fault, bus error, etc.)
while CPU Hotplug (e.g. one CPU is using clear_page() while another is
generating it in cpu_cache_init()).
For similar reasons we modify build_tlb_refill_handler()'s invocation.
V2:
1, Rework the code to make CPU#0 can be online/offline.
2, Introduce cpu_has_local_ebase feature since some types of MIPS CPU
need a per-CPU tlb_refill_handler().
Signed-off-by: Huacai Chen <chenhc@xxxxxxxxxx>
Signed-off-by: Hongbing Hu <huhb@xxxxxxxxxx>
---
arch/mips/include/asm/cpu-features.h | 3 +++
.../asm/mach-loongson/cpu-feature-overrides.h | 1 +
arch/mips/mm/page.c | 10 ++++++++++
arch/mips/mm/tlbex.c | 10 ++++++++--
4 files changed, 22 insertions(+), 2 deletions(-)
diff --git a/arch/mips/include/asm/cpu-features.h b/arch/mips/include/asm/cpu-features.h
index c507b93..1204408 100644
--- a/arch/mips/include/asm/cpu-features.h
+++ b/arch/mips/include/asm/cpu-features.h
@@ -110,6 +110,9 @@
#ifndef cpu_has_pindexed_dcache
#define cpu_has_pindexed_dcache (cpu_data[0].dcache.flags & MIPS_CACHE_PINDEX)
#endif
+#ifndef cpu_has_local_ebase
+#define cpu_has_local_ebase 1
+#endif
/*
* I-Cache snoops remote store. This only matters on SMP. Some multiprocessors
diff --git a/arch/mips/include/asm/mach-loongson/cpu-feature-overrides.h b/arch/mips/include/asm/mach-loongson/cpu-feature-overrides.h
index 1a05d85..8eec8e2 100644
--- a/arch/mips/include/asm/mach-loongson/cpu-feature-overrides.h
+++ b/arch/mips/include/asm/mach-loongson/cpu-feature-overrides.h
@@ -57,5 +57,6 @@
#define cpu_has_vint 0
#define cpu_has_vtag_icache 0
#define cpu_has_watch 1
+#define cpu_has_local_ebase 0
#endif /* __ASM_MACH_LOONGSON_CPU_FEATURE_OVERRIDES_H */
diff --git a/arch/mips/mm/page.c b/arch/mips/mm/page.c
index 8e666c5..6a39c01 100644
--- a/arch/mips/mm/page.c
+++ b/arch/mips/mm/page.c
@@ -247,6 +247,11 @@ void __cpuinit build_clear_page(void)
struct uasm_label *l = labels;
struct uasm_reloc *r = relocs;
int i;
+ static atomic_t run_once = ATOMIC_INIT(0);
+
+ if (atomic_xchg(&run_once, 1)) {
+ return;
+ }
memset(labels, 0, sizeof(labels));
memset(relocs, 0, sizeof(relocs));
@@ -389,6 +394,11 @@ void __cpuinit build_copy_page(void)
struct uasm_label *l = labels;
struct uasm_reloc *r = relocs;
int i;
+ static atomic_t run_once = ATOMIC_INIT(0);
+
+ if (atomic_xchg(&run_once, 1)) {
+ return;
+ }
memset(labels, 0, sizeof(labels));
memset(relocs, 0, sizeof(relocs));
diff --git a/arch/mips/mm/tlbex.c b/arch/mips/mm/tlbex.c
index 1c8ac49..4a8b294 100644
--- a/arch/mips/mm/tlbex.c
+++ b/arch/mips/mm/tlbex.c
@@ -2161,8 +2161,11 @@ void __cpuinit build_tlb_refill_handler(void)
case CPU_TX3922:
case CPU_TX3927:
#ifndef CONFIG_MIPS_PGD_C0_CONTEXT
- build_r3000_tlb_refill_handler();
+ if (cpu_has_local_ebase)
+ build_r3000_tlb_refill_handler();
if (!run_once) {
+ if (!cpu_has_local_ebase)
+ build_r3000_tlb_refill_handler();
build_r3000_tlb_load_handler();
build_r3000_tlb_store_handler();
build_r3000_tlb_modify_handler();
@@ -2191,9 +2194,12 @@ void __cpuinit build_tlb_refill_handler(void)
build_r4000_tlb_load_handler();
build_r4000_tlb_store_handler();
build_r4000_tlb_modify_handler();
+ if (!cpu_has_local_ebase)
+ build_r4000_tlb_refill_handler();
run_once++;
}
- build_r4000_tlb_refill_handler();
+ if (cpu_has_local_ebase)
+ build_r4000_tlb_refill_handler();
}
}
--
1.7.7.3
