diff options
| -rw-r--r-- | arch/powerpc/include/asm/cputhreads.h | 16 | ||||
| -rw-r--r-- | arch/powerpc/mm/mmu_context_nohash.c | 93 | ||||
| -rw-r--r-- | arch/powerpc/mm/tlb_nohash.c | 10 |
3 files changed, 86 insertions, 33 deletions
diff --git a/arch/powerpc/include/asm/cputhreads.h b/arch/powerpc/include/asm/cputhreads.h index fb11b0c459b..a8e18447c62 100644 --- a/arch/powerpc/include/asm/cputhreads.h +++ b/arch/powerpc/include/asm/cputhreads.h @@ -5,6 +5,15 @@ /* * Mapping of threads to cores + * + * Note: This implementation is limited to a power of 2 number of + * threads per core and the same number for each core in the system + * (though it would work if some processors had less threads as long + * as the CPU numbers are still allocated, just not brought offline). + * + * However, the API allows for a different implementation in the future + * if needed, as long as you only use the functions and not the variables + * directly. */ #ifdef CONFIG_SMP @@ -67,5 +76,12 @@ static inline int cpu_first_thread_in_core(int cpu) return cpu & ~(threads_per_core - 1); } +static inline int cpu_last_thread_in_core(int cpu) +{ + return cpu | (threads_per_core - 1); +} + + + #endif /* _ASM_POWERPC_CPUTHREADS_H */ diff --git a/arch/powerpc/mm/mmu_context_nohash.c b/arch/powerpc/mm/mmu_context_nohash.c index b1a727def15..834436d6d6b 100644 --- a/arch/powerpc/mm/mmu_context_nohash.c +++ b/arch/powerpc/mm/mmu_context_nohash.c @@ -25,10 +25,20 @@ * also clear mm->cpu_vm_mask bits when processes are migrated */ -#undef DEBUG -#define DEBUG_STEAL_ONLY -#undef DEBUG_MAP_CONSISTENCY -/*#define DEBUG_CLAMP_LAST_CONTEXT 15 */ +#define DEBUG_MAP_CONSISTENCY +#define DEBUG_CLAMP_LAST_CONTEXT 31 +//#define DEBUG_HARDER + +/* We don't use DEBUG because it tends to be compiled in always nowadays + * and this would generate way too much output + */ +#ifdef DEBUG_HARDER +#define pr_hard(args...) printk(KERN_DEBUG args) +#define pr_hardcont(args...) printk(KERN_CONT args) +#else +#define pr_hard(args...) do { } while(0) +#define pr_hardcont(args...) do { } while(0) +#endif #include <linux/kernel.h> #include <linux/mm.h> @@ -71,7 +81,7 @@ static DEFINE_SPINLOCK(context_lock); static unsigned int steal_context_smp(unsigned int id) { struct mm_struct *mm; - unsigned int cpu, max; + unsigned int cpu, max, i; max = last_context - first_context; @@ -89,15 +99,22 @@ static unsigned int steal_context_smp(unsigned int id) id = first_context; continue; } - pr_devel("[%d] steal context %d from mm @%p\n", - smp_processor_id(), id, mm); + pr_hardcont(" | steal %d from 0x%p", id, mm); /* Mark this mm has having no context anymore */ mm->context.id = MMU_NO_CONTEXT; - /* Mark it stale on all CPUs that used this mm */ - for_each_cpu(cpu, mm_cpumask(mm)) - __set_bit(id, stale_map[cpu]); + /* Mark it stale on all CPUs that used this mm. For threaded + * implementations, we set it on all threads on each core + * represented in the mask. A future implementation will use + * a core map instead but this will do for now. + */ + for_each_cpu(cpu, mm_cpumask(mm)) { + for (i = cpu_first_thread_in_core(cpu); + i <= cpu_last_thread_in_core(cpu); i++) + __set_bit(id, stale_map[i]); + cpu = i - 1; + } return id; } @@ -126,7 +143,7 @@ static unsigned int steal_context_up(unsigned int id) /* Pick up the victim mm */ mm = context_mm[id]; - pr_devel("[%d] steal context %d from mm @%p\n", cpu, id, mm); + pr_hardcont(" | steal %d from 0x%p", id, mm); /* Flush the TLB for that context */ local_flush_tlb_mm(mm); @@ -179,19 +196,14 @@ void switch_mmu_context(struct mm_struct *prev, struct mm_struct *next) /* No lockless fast path .. yet */ spin_lock(&context_lock); -#ifndef DEBUG_STEAL_ONLY - pr_devel("[%d] activating context for mm @%p, active=%d, id=%d\n", - cpu, next, next->context.active, next->context.id); -#endif + pr_hard("[%d] activating context for mm @%p, active=%d, id=%d", + cpu, next, next->context.active, next->context.id); #ifdef CONFIG_SMP /* Mark us active and the previous one not anymore */ next->context.active++; if (prev) { -#ifndef DEBUG_STEAL_ONLY - pr_devel(" old context %p active was: %d\n", - prev, prev->context.active); -#endif + pr_hardcont(" (old=0x%p a=%d)", prev, prev->context.active); WARN_ON(prev->context.active < 1); prev->context.active--; } @@ -201,8 +213,14 @@ void switch_mmu_context(struct mm_struct *prev, struct mm_struct *next) /* If we already have a valid assigned context, skip all that */ id = next->context.id; - if (likely(id != MMU_NO_CONTEXT)) + if (likely(id != MMU_NO_CONTEXT)) { +#ifdef DEBUG_MAP_CONSISTENCY + if (context_mm[id] != next) + pr_err("MMU: mm 0x%p has id %d but context_mm[%d] says 0x%p\n", + next, id, id, context_mm[id]); +#endif goto ctxt_ok; + } /* We really don't have a context, let's try to acquire one */ id = next_context; @@ -235,11 +253,7 @@ void switch_mmu_context(struct mm_struct *prev, struct mm_struct *next) next_context = id + 1; context_mm[id] = next; next->context.id = id; - -#ifndef DEBUG_STEAL_ONLY - pr_devel("[%d] picked up new id %d, nrf is now %d\n", - cpu, id, nr_free_contexts); -#endif + pr_hardcont(" | new id=%d,nrf=%d", id, nr_free_contexts); context_check_map(); ctxt_ok: @@ -248,15 +262,20 @@ void switch_mmu_context(struct mm_struct *prev, struct mm_struct *next) * local TLB for it and unmark it before we use it */ if (test_bit(id, stale_map[cpu])) { - pr_devel("[%d] flushing stale context %d for mm @%p !\n", - cpu, id, next); + pr_hardcont(" | stale flush %d [%d..%d]", + id, cpu_first_thread_in_core(cpu), + cpu_last_thread_in_core(cpu)); + local_flush_tlb_mm(next); /* XXX This clear should ultimately be part of local_flush_tlb_mm */ - __clear_bit(id, stale_map[cpu]); + for (cpu = cpu_first_thread_in_core(cpu); + cpu <= cpu_last_thread_in_core(cpu); cpu++) + __clear_bit(id, stale_map[cpu]); } /* Flick the MMU and release lock */ + pr_hardcont(" -> %d\n", id); set_context(id, next->pgd); spin_unlock(&context_lock); } @@ -266,6 +285,8 @@ void switch_mmu_context(struct mm_struct *prev, struct mm_struct *next) */ int init_new_context(struct task_struct *t, struct mm_struct *mm) { + pr_hard("initing context for mm @%p\n", mm); + mm->context.id = MMU_NO_CONTEXT; mm->context.active = 0; @@ -305,7 +326,9 @@ static int __cpuinit mmu_context_cpu_notify(struct notifier_block *self, unsigned long action, void *hcpu) { unsigned int cpu = (unsigned int)(long)hcpu; - +#ifdef CONFIG_HOTPLUG_CPU + struct task_struct *p; +#endif /* We don't touch CPU 0 map, it's allocated at aboot and kept * around forever */ @@ -324,8 +347,16 @@ static int __cpuinit mmu_context_cpu_notify(struct notifier_block *self, pr_devel("MMU: Freeing stale context map for CPU %d\n", cpu); kfree(stale_map[cpu]); stale_map[cpu] = NULL; - break; -#endif + + /* We also clear the cpu_vm_mask bits of CPUs going away */ + read_lock(&tasklist_lock); + for_each_process(p) { + if (p->mm) + cpu_mask_clear_cpu(cpu, mm_cpumask(p->mm)); + } + read_unlock(&tasklist_lock); + break; +#endif /* CONFIG_HOTPLUG_CPU */ } return NOTIFY_OK; } diff --git a/arch/powerpc/mm/tlb_nohash.c b/arch/powerpc/mm/tlb_nohash.c index ad2eb4d34dd..d908e75cc3b 100644 --- a/arch/powerpc/mm/tlb_nohash.c +++ b/arch/powerpc/mm/tlb_nohash.c @@ -87,6 +87,12 @@ EXPORT_SYMBOL(local_flush_tlb_page); static DEFINE_SPINLOCK(tlbivax_lock); +static int mm_is_core_local(struct mm_struct *mm) +{ + return cpumask_subset(mm_cpumask(mm), + topology_thread_cpumask(smp_processor_id())); +} + struct tlb_flush_param { unsigned long addr; unsigned int pid; @@ -131,7 +137,7 @@ void flush_tlb_mm(struct mm_struct *mm) pid = mm->context.id; if (unlikely(pid == MMU_NO_CONTEXT)) goto no_context; - if (!cpumask_equal(mm_cpumask(mm), cpumask_of(smp_processor_id()))) { + if (!mm_is_core_local(mm)) { struct tlb_flush_param p = { .pid = pid }; /* Ignores smp_processor_id() even if set. */ smp_call_function_many(mm_cpumask(mm), @@ -153,7 +159,7 @@ void flush_tlb_page(struct vm_area_struct *vma, unsigned long vmaddr) if (unlikely(pid == MMU_NO_CONTEXT)) goto bail; cpu_mask = mm_cpumask(vma->vm_mm); - if (!cpumask_equal(cpu_mask, cpumask_of(smp_processor_id()))) { + if (!mm_is_core_local(mm)) { /* If broadcast tlbivax is supported, use it */ if (mmu_has_feature(MMU_FTR_USE_TLBIVAX_BCAST)) { int lock = mmu_has_feature(MMU_FTR_LOCK_BCAST_INVAL); |