diff --git a/mm/vmalloc.c b/mm/vmalloc.c index 9bb6610f499b..33e245ebe70c 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -331,6 +331,7 @@ EXPORT_SYMBOL(vmalloc_to_pfn); static DEFINE_SPINLOCK(vmap_area_lock); +static DEFINE_SPINLOCK(free_vmap_area_lock); /* Export for kexec only */ LIST_HEAD(vmap_area_list); static LLIST_HEAD(vmap_purge_list); @@ -1114,7 +1115,7 @@ static struct vmap_area *alloc_vmap_area(unsigned long size, */ pva = kmem_cache_alloc_node(vmap_area_cachep, gfp_mask, node); - spin_lock(&vmap_area_lock); + spin_lock(&free_vmap_area_lock); if (pva && __this_cpu_cmpxchg(ne_fit_preload_node, NULL, pva)) kmem_cache_free(vmap_area_cachep, pva); @@ -1124,14 +1125,17 @@ static struct vmap_area *alloc_vmap_area(unsigned long size, * returned. Therefore trigger the overflow path. */ addr = __alloc_vmap_area(size, align, vstart, vend); + spin_unlock(&free_vmap_area_lock); + if (unlikely(addr == vend)) goto overflow; va->va_start = addr; va->va_end = addr + size; va->vm = NULL; - insert_vmap_area(va, &vmap_area_root, &vmap_area_list); + spin_lock(&vmap_area_lock); + insert_vmap_area(va, &vmap_area_root, &vmap_area_list); spin_unlock(&vmap_area_lock); BUG_ON(!IS_ALIGNED(va->va_start, align)); @@ -1141,7 +1145,6 @@ static struct vmap_area *alloc_vmap_area(unsigned long size, return va; overflow: - spin_unlock(&vmap_area_lock); if (!purged) { purge_vmap_area_lazy(); purged = 1; @@ -1177,28 +1180,25 @@ int unregister_vmap_purge_notifier(struct notifier_block *nb) } EXPORT_SYMBOL_GPL(unregister_vmap_purge_notifier); -static void __free_vmap_area(struct vmap_area *va) -{ - /* - * Remove from the busy tree/list. - */ - unlink_va(va, &vmap_area_root); - - /* - * Merge VA with its neighbors, otherwise just add it. - */ - merge_or_add_vmap_area(va, - &free_vmap_area_root, &free_vmap_area_list); -} - /* * Free a region of KVA allocated by alloc_vmap_area */ static void free_vmap_area(struct vmap_area *va) { + /* + * Remove from the busy tree/list. + */ spin_lock(&vmap_area_lock); - __free_vmap_area(va); + unlink_va(va, &vmap_area_root); spin_unlock(&vmap_area_lock); + + /* + * Insert/Merge it back to the free tree/list. + */ + spin_lock(&free_vmap_area_lock); + merge_or_add_vmap_area(va, + &free_vmap_area_root, &free_vmap_area_list); + spin_unlock(&free_vmap_area_lock); } /* @@ -1291,7 +1291,7 @@ static bool __purge_vmap_area_lazy(unsigned long start, unsigned long end) flush_tlb_kernel_range(start, end); resched_threshold = lazy_max_pages() << 1; - spin_lock(&vmap_area_lock); + spin_lock(&free_vmap_area_lock); llist_for_each_entry_safe(va, n_va, valist, purge_list) { unsigned long nr = (va->va_end - va->va_start) >> PAGE_SHIFT; @@ -1306,9 +1306,9 @@ static bool __purge_vmap_area_lazy(unsigned long start, unsigned long end) atomic_long_sub(nr, &vmap_lazy_nr); if (atomic_long_read(&vmap_lazy_nr) < resched_threshold) - cond_resched_lock(&vmap_area_lock); + cond_resched_lock(&free_vmap_area_lock); } - spin_unlock(&vmap_area_lock); + spin_unlock(&free_vmap_area_lock); return true; } @@ -2030,15 +2030,21 @@ int map_vm_area(struct vm_struct *area, pgprot_t prot, struct page **pages) } EXPORT_SYMBOL_GPL(map_vm_area); -static void setup_vmalloc_vm(struct vm_struct *vm, struct vmap_area *va, - unsigned long flags, const void *caller) +static inline void setup_vmalloc_vm_locked(struct vm_struct *vm, + struct vmap_area *va, unsigned long flags, const void *caller) { - spin_lock(&vmap_area_lock); vm->flags = flags; vm->addr = (void *)va->va_start; vm->size = va->va_end - va->va_start; vm->caller = caller; va->vm = vm; +} + +static void setup_vmalloc_vm(struct vm_struct *vm, struct vmap_area *va, + unsigned long flags, const void *caller) +{ + spin_lock(&vmap_area_lock); + setup_vmalloc_vm_locked(vm, va, flags, caller); spin_unlock(&vmap_area_lock); } @@ -3298,7 +3304,7 @@ struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets, goto err_free; } retry: - spin_lock(&vmap_area_lock); + spin_lock(&free_vmap_area_lock); /* start scanning - we scan from the top, begin with the last area */ area = term_area = last_area; @@ -3380,29 +3386,38 @@ struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets, va = vas[area]; va->va_start = start; va->va_end = start + size; - - insert_vmap_area(va, &vmap_area_root, &vmap_area_list); } - spin_unlock(&vmap_area_lock); + spin_unlock(&free_vmap_area_lock); /* insert all vm's */ - for (area = 0; area < nr_vms; area++) - setup_vmalloc_vm(vms[area], vas[area], VM_ALLOC, + spin_lock(&vmap_area_lock); + for (area = 0; area < nr_vms; area++) { + insert_vmap_area(vas[area], &vmap_area_root, &vmap_area_list); + + setup_vmalloc_vm_locked(vms[area], vas[area], VM_ALLOC, pcpu_get_vm_areas); + } + spin_unlock(&vmap_area_lock); kfree(vas); return vms; recovery: - /* Remove previously inserted areas. */ + /* + * Remove previously allocated areas. There is no + * need in removing these areas from the busy tree, + * because they are inserted only on the final step + * and when pcpu_get_vm_areas() is success. + */ while (area--) { - __free_vmap_area(vas[area]); + merge_or_add_vmap_area(vas[area], + &free_vmap_area_root, &free_vmap_area_list); vas[area] = NULL; } overflow: - spin_unlock(&vmap_area_lock); + spin_unlock(&free_vmap_area_lock); if (!purged) { purge_vmap_area_lazy(); purged = true; @@ -3453,9 +3468,12 @@ void pcpu_free_vm_areas(struct vm_struct **vms, int nr_vms) #ifdef CONFIG_PROC_FS static void *s_start(struct seq_file *m, loff_t *pos) + __acquires(&vmap_purge_lock) __acquires(&vmap_area_lock) { + mutex_lock(&vmap_purge_lock); spin_lock(&vmap_area_lock); + return seq_list_start(&vmap_area_list, *pos); } @@ -3465,8 +3483,10 @@ static void *s_next(struct seq_file *m, void *p, loff_t *pos) } static void s_stop(struct seq_file *m, void *p) + __releases(&vmap_purge_lock) __releases(&vmap_area_lock) { + mutex_unlock(&vmap_purge_lock); spin_unlock(&vmap_area_lock); }