#include <linux/mm.h> #include <linux/mmzone.h> #include <linux/bootmem.h> #include <linux/bit_spinlock.h> #include <linux/page_cgroup.h> #include <linux/hash.h> #include <linux/slab.h> #include <linux/memory.h> #include <linux/vmalloc.h> #include <linux/cgroup.h> #include <linux/swapops.h> #include <linux/kmemleak.h> static void __meminit init_page_cgroup(struct page_cgroup *pc, unsigned long id) { pc->flags = 0; set_page_cgroup_array_id(pc, id); pc->mem_cgroup = NULL; INIT_LIST_HEAD(&pc->lru); } static unsigned long total_usage; #if !defined(CONFIG_SPARSEMEM) void __meminit pgdat_page_cgroup_init(struct pglist_data *pgdat) { pgdat->node_page_cgroup = NULL; } struct page_cgroup *lookup_page_cgroup(struct page *page) { unsigned long pfn = page_to_pfn(page); unsigned long offset; struct page_cgroup *base; base = NODE_DATA(page_to_nid(page))->node_page_cgroup; if (unlikely(!base)) return NULL; offset = pfn - NODE_DATA(page_to_nid(page))->node_start_pfn; return base + offset; } struct page *lookup_cgroup_page(struct page_cgroup *pc) { unsigned long pfn; struct page *page; pg_data_t *pgdat; pgdat = NODE_DATA(page_cgroup_array_id(pc)); pfn = pc - pgdat->node_page_cgroup + pgdat->node_start_pfn; page = pfn_to_page(pfn); VM_BUG_ON(pc != lookup_page_cgroup(page)); return page; } static int __init alloc_node_page_cgroup(int nid) { struct page_cgroup *base, *pc; unsigned long table_size; unsigned long start_pfn, nr_pages, index; start_pfn = NODE_DATA(nid)->node_start_pfn; nr_pages = NODE_DATA(nid)->node_spanned_pages; if (!nr_pages) return 0; table_size = sizeof(struct page_cgroup) * nr_pages; base = __alloc_bootmem_node_nopanic(NODE_DATA(nid), table_size, PAGE_SIZE, __pa(MAX_DMA_ADDRESS)); if (!base) return -ENOMEM; for (index = 0; index < nr_pages; index++) { pc = base + index; init_page_cgroup(pc, nid); } NODE_DATA(nid)->node_page_cgroup = base; total_usage += table_size; return 0; } void __init page_cgroup_init_flatmem(void) { int nid, fail; if (mem_cgroup_disabled()) return; for_each_online_node(nid) { fail = alloc_node_page_cgroup(nid); if (fail) goto fail; } printk(KERN_INFO "allocated %ld bytes of page_cgroup\n", total_usage); printk(KERN_INFO "please try 'cgroup_disable=memory' option if you" " don't want memory cgroups\n"); return; fail: printk(KERN_CRIT "allocation of page_cgroup failed.\n"); printk(KERN_CRIT "please try 'cgroup_disable=memory' boot option\n"); panic("Out of memory"); } #else /* CONFIG_FLAT_NODE_MEM_MAP */ struct page_cgroup *lookup_page_cgroup(struct page *page) { unsigned long pfn = page_to_pfn(page); struct mem_section *section = __pfn_to_section(pfn); if (!section->page_cgroup) return NULL; return section->page_cgroup + pfn; } struct page *lookup_cgroup_page(struct page_cgroup *pc) { struct mem_section *section; struct page *page; unsigned long nr; nr = page_cgroup_array_id(pc); section = __nr_to_section(nr); page = pfn_to_page(pc - section->page_cgroup); VM_BUG_ON(pc != lookup_page_cgroup(page)); return page; } static void *__init_refok alloc_page_cgroup(size_t size, int nid) { void *addr = NULL; addr = alloc_pages_exact(size, GFP_KERNEL | __GFP_NOWARN); if (addr) return addr; if (node_state(nid, N_HIGH_MEMORY)) addr = vmalloc_node(size, nid); else addr = vmalloc(size); return addr; } #ifdef CONFIG_MEMORY_HOTPLUG static void free_page_cgroup(void *addr) { if (is_vmalloc_addr(addr)) { vfree(addr); } else { struct page *page = virt_to_page(addr); size_t table_size = sizeof(struct page_cgroup) * PAGES_PER_SECTION; BUG_ON(PageReserved(page)); free_pages_exact(addr, table_size); } } #endif static int __init_refok init_section_page_cgroup(unsigned long pfn) { struct page_cgroup *base, *pc; struct mem_section *section; unsigned long table_size; unsigned long nr; int nid, index; nr = pfn_to_section_nr(pfn); section = __nr_to_section(nr); if (section->page_cgroup) return 0; nid = page_to_nid(pfn_to_page(pfn)); table_size = sizeof(struct page_cgroup) * PAGES_PER_SECTION; base = alloc_page_cgroup(table_size, nid); /* * The value stored in section->page_cgroup is (base - pfn) * and it does not point to the memory block allocated above, * causing kmemleak false positives. */ kmemleak_not_leak(base); if (!base) { printk(KERN_ERR "page cgroup allocation failure\n"); return -ENOMEM; } for (index = 0; index < PAGES_PER_SECTION; index++) { pc = base + index; init_page_cgroup(pc, nr); } section->page_cgroup = base - pfn; total_usage += table_size; return 0; } #ifdef CONFIG_MEMORY_HOTPLUG void __free_page_cgroup(unsigned long pfn) { struct mem_section *ms; struct page_cgroup *base; ms = __pfn_to_section(pfn); if (!ms || !ms->page_cgroup) return; base = ms->page_cgroup + pfn; free_page_cgroup(base); ms->page_cgroup = NULL; } int __meminit online_page_cgroup(unsigned long start_pfn, unsigned long nr_pages, int nid) { unsigned long start, end, pfn; int fail = 0; start = start_pfn & ~(PAGES_PER_SECTION - 1); end = ALIGN(start_pfn + nr_pages, PAGES_PER_SECTION); for (pfn = start; !fail && pfn < end; pfn += PAGES_PER_SECTION) { if (!pfn_present(pfn)) continue; fail = init_section_page_cgroup(pfn); } if (!fail) return 0; /* rollback */ for (pfn = start; pfn < end; pfn += PAGES_PER_SECTION) __free_page_cgroup(pfn); return -ENOMEM; } int __meminit offline_page_cgroup(unsigned long start_pfn, unsigned long nr_pages, int nid) { unsigned long start, end, pfn; start = start_pfn & ~(PAGES_PER_SECTION - 1); end = ALIGN(start_pfn + nr_pages, PAGES_PER_SECTION); for (pfn = start; pfn < end; pfn += PAGES_PER_SECTION) __free_page_cgroup(pfn); return 0; } static int __meminit page_cgroup_callback(struct notifier_block *self, unsigned long action, void *arg) { struct memory_notify *mn = arg; int ret = 0; switch (action) { case MEM_GOING_ONLINE: ret = online_page_cgroup(mn->start_pfn, mn->nr_pages, mn->status_change_nid); break; case MEM_OFFLINE: offline_page_cgroup(mn->start_pfn, mn->nr_pages, mn->status_change_nid); break; case MEM_CANCEL_ONLINE: case MEM_GOING_OFFLINE: break; case MEM_ONLINE: case MEM_CANCEL_OFFLINE: break; } return notifier_from_errno(ret); } #endif void __init page_cgroup_init(void) { unsigned long pfn; int fail = 0; if (mem_cgroup_disabled()) return; for (pfn = 0; !fail && pfn < max_pfn; pfn += PAGES_PER_SECTION) { if (!pfn_present(pfn)) continue; fail = init_section_page_cgroup(pfn); } if (fail) { printk(KERN_CRIT "try 'cgroup_disable=memory' boot option\n"); panic("Out of memory"); } else { hotplug_memory_notifier(page_cgroup_callback, 0); } printk(KERN_INFO "allocated %ld bytes of page_cgroup\n", total_usage); printk(KERN_INFO "please try 'cgroup_disable=memory' option if you don't" " want memory cgroups\n"); } void __meminit pgdat_page_cgroup_init(struct pglist_data *pgdat) { return; } #endif #ifdef CONFIG_CGROUP_MEM_RES_CTLR_SWAP static DEFINE_MUTEX(swap_cgroup_mutex); struct swap_cgroup_ctrl { struct page **map; unsigned long length; spinlock_t lock; }; struct swap_cgroup_ctrl swap_cgroup_ctrl[MAX_SWAPFILES]; struct swap_cgroup { unsigned short id; }; #define SC_PER_PAGE (PAGE_SIZE/sizeof(struct swap_cgroup)) #define SC_POS_MASK (SC_PER_PAGE - 1) /* * SwapCgroup implements "lookup" and "exchange" operations. * In typical usage, this swap_cgroup is accessed via memcg's charge/uncharge * against SwapCache. At swap_free(), this is accessed directly from swap. * * This means, * - we have no race in "exchange" when we're accessed via SwapCache because * SwapCache(and its swp_entry) is under lock. * - When called via swap_free(), there is no user of this entry and no race. * Then, we don't need lock around "exchange". * * TODO: we can push these buffers out to HIGHMEM. */ /* * allocate buffer for swap_cgroup. */ static int swap_cgroup_prepare(int type) { struct page *page; struct swap_cgroup_ctrl *ctrl; unsigned long idx, max; ctrl = &swap_cgroup_ctrl[type]; for (idx = 0; idx < ctrl->length; idx++) { page = alloc_page(GFP_KERNEL | __GFP_ZERO); if (!page) goto not_enough_page; ctrl->map[idx] = page; } return 0; not_enough_page: max = idx; for (idx = 0; idx < max; idx++) __free_page(ctrl->map[idx]); return -ENOMEM; } /** * swap_cgroup_cmpxchg - cmpxchg mem_cgroup's id for this swp_entry. * @end: swap entry to be cmpxchged * @old: old id * @new: new id * * Returns old id at success, 0 at failure. * (There is no mem_cgroup using 0 as its id) */ unsigned short swap_cgroup_cmpxchg(swp_entry_t ent, unsigned short old, unsigned short new) { int type = swp_type(ent); unsigned long offset = swp_offset(ent); unsigned long idx = offset / SC_PER_PAGE; unsigned long pos = offset & SC_POS_MASK; struct swap_cgroup_ctrl *ctrl; struct page *mappage; struct swap_cgroup *sc; unsigned long flags; unsigned short retval; ctrl = &swap_cgroup_ctrl[type]; mappage = ctrl->map[idx]; sc = page_address(mappage); sc += pos; spin_lock_irqsave(&ctrl->lock, flags); retval = sc->id; if (retval == old) sc->id = new; else retval = 0; spin_unlock_irqrestore(&ctrl->lock, flags); return retval; } /** * swap_cgroup_record - record mem_cgroup for this swp_entry. * @ent: swap entry to be recorded into * @mem: mem_cgroup to be recorded * * Returns old value at success, 0 at failure. * (Of course, old value can be 0.) */ unsigned short swap_cgroup_record(swp_entry_t ent, unsigned short id) { int type = swp_type(ent); unsigned long offset = swp_offset(ent); unsigned long idx = offset / SC_PER_PAGE; unsigned long pos = offset & SC_POS_MASK; struct swap_cgroup_ctrl *ctrl; struct page *mappage; struct swap_cgroup *sc; unsigned short old; unsigned long flags; ctrl = &swap_cgroup_ctrl[type]; mappage = ctrl->map[idx]; sc = page_address(mappage); sc += pos; spin_lock_irqsave(&ctrl->lock, flags); old = sc->id; sc->id = id; spin_unlock_irqrestore(&ctrl->lock, flags); return old; } /** * lookup_swap_cgroup - lookup mem_cgroup tied to swap entry * @ent: swap entry to be looked up. * * Returns CSS ID of mem_cgroup at success. 0 at failure. (0 is invalid ID) */ unsigned short lookup_swap_cgroup(swp_entry_t ent) { int type = swp_type(ent); unsigned long offset = swp_offset(ent); unsigned long idx = offset / SC_PER_PAGE; unsigned long pos = offset & SC_POS_MASK; struct swap_cgroup_ctrl *ctrl; struct page *mappage; struct swap_cgroup *sc; unsigned short ret; ctrl = &swap_cgroup_ctrl[type]; mappage = ctrl->map[idx]; sc = page_address(mappage); sc += pos; ret = sc->id; return ret; } int swap_cgroup_swapon(int type, unsigned long max_pages) { void *array; unsigned long array_size; unsigned long length; struct swap_cgroup_ctrl *ctrl; if (!do_swap_account) return 0; length = ((max_pages/SC_PER_PAGE) + 1); array_size = length * sizeof(void *); array = vmalloc(array_size); if (!array) goto nomem; memset(array, 0, array_size); ctrl = &swap_cgroup_ctrl[type]; mutex_lock(&swap_cgroup_mutex); ctrl->length = length; ctrl->map = array; spin_lock_init(&ctrl->lock); if (swap_cgroup_prepare(type)) { /* memory shortage */ ctrl->map = NULL; ctrl->length = 0; vfree(array); mutex_unlock(&swap_cgroup_mutex); goto nomem; } mutex_unlock(&swap_cgroup_mutex); return 0; nomem: printk(KERN_INFO "couldn't allocate enough memory for swap_cgroup.\n"); printk(KERN_INFO "swap_cgroup can be disabled by noswapaccount boot option\n"); return -ENOMEM; } void swap_cgroup_swapoff(int type) { int i; struct swap_cgroup_ctrl *ctrl; if (!do_swap_account) return; mutex_lock(&swap_cgroup_mutex); ctrl = &swap_cgroup_ctrl[type]; if (ctrl->map) { for (i = 0; i < ctrl->length; i++) { struct page *page = ctrl->map[i]; if (page) __free_page(page); } vfree(ctrl->map); ctrl->map = NULL; ctrl->length = 0; } mutex_unlock(&swap_cgroup_mutex); } #endif