From 8697d33194faae6fdd6b2e799f6308aa00cfdf67 Mon Sep 17 00:00:00 2001 From: Balbir Singh Date: Thu, 7 Feb 2008 00:13:59 -0800 Subject: [PATCH] Memory controller: add switch to control what type of pages to limit Choose if we want cached pages to be accounted or not. By default both are accounted for. A new set of tunables are added. echo -n 1 > mem_control_type switches the accounting to account for only mapped pages echo -n 3 > mem_control_type switches the behaviour back [bunk@kernel.org: mm/memcontrol.c: clenups] [akpm@linux-foundation.org: fix sparc32 build] Signed-off-by: Balbir Singh Cc: Pavel Emelianov Cc: Paul Menage Cc: Peter Zijlstra Cc: "Eric W. Biederman" Cc: Nick Piggin Cc: Kirill Korotaev Cc: Herbert Poetzl Cc: David Rientjes Cc: Vaidyanathan Srinivasan Signed-off-by: Adrian Bunk Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/memcontrol.h | 9 ++++ mm/filemap.c | 2 +- mm/memcontrol.c | 98 ++++++++++++++++++++++++++++++++++++-- mm/swap_state.c | 2 +- 4 files changed, 106 insertions(+), 5 deletions(-) diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 9bbbf524ba8..bb6f5105401 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -22,6 +22,8 @@ struct mem_cgroup; struct page_cgroup; +struct page; +struct mm_struct; #ifdef CONFIG_CGROUP_MEM_CONT @@ -40,6 +42,7 @@ extern unsigned long mem_cgroup_isolate_pages(unsigned long nr_to_scan, struct mem_cgroup *mem_cont, int active); extern void mem_cgroup_out_of_memory(struct mem_cgroup *mem, gfp_t gfp_mask); +extern int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm); static inline void mem_cgroup_uncharge_page(struct page *page) { @@ -84,6 +87,12 @@ static inline void mem_cgroup_move_lists(struct page_cgroup *pc, { } +static inline int mem_cgroup_cache_charge(struct page *page, + struct mm_struct *mm) +{ + return 0; +} + #endif /* CONFIG_CGROUP_MEM_CONT */ #endif /* _LINUX_MEMCONTROL_H */ diff --git a/mm/filemap.c b/mm/filemap.c index b7a01e92795..8ae171cc281 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -464,7 +464,7 @@ int add_to_page_cache(struct page *page, struct address_space *mapping, if (error == 0) { - error = mem_cgroup_charge(page, current->mm); + error = mem_cgroup_cache_charge(page, current->mm); if (error) goto out; diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 5260658c90a..10833d969e3 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -29,6 +29,8 @@ #include #include +#include + struct cgroup_subsys mem_cgroup_subsys; static const int MEM_CGROUP_RECLAIM_RETRIES = 5; @@ -60,6 +62,7 @@ struct mem_cgroup { * spin_lock to protect the per cgroup LRU */ spinlock_t lru_lock; + unsigned long control_type; /* control RSS or RSS+Pagecache */ }; /* @@ -82,6 +85,15 @@ struct page_cgroup { /* mapped and cached states */ }; +enum { + MEM_CGROUP_TYPE_UNSPEC = 0, + MEM_CGROUP_TYPE_MAPPED, + MEM_CGROUP_TYPE_CACHED, + MEM_CGROUP_TYPE_ALL, + MEM_CGROUP_TYPE_MAX, +}; + +static struct mem_cgroup init_mem_cgroup; static inline struct mem_cgroup *mem_cgroup_from_cont(struct cgroup *cont) @@ -139,18 +151,18 @@ struct page_cgroup *page_get_page_cgroup(struct page *page) (page->page_cgroup & ~PAGE_CGROUP_LOCK); } -void __always_inline lock_page_cgroup(struct page *page) +static void __always_inline lock_page_cgroup(struct page *page) { bit_spin_lock(PAGE_CGROUP_LOCK_BIT, &page->page_cgroup); VM_BUG_ON(!page_cgroup_locked(page)); } -void __always_inline unlock_page_cgroup(struct page *page) +static void __always_inline unlock_page_cgroup(struct page *page) { bit_spin_unlock(PAGE_CGROUP_LOCK_BIT, &page->page_cgroup); } -void __mem_cgroup_move_lists(struct page_cgroup *pc, bool active) +static void __mem_cgroup_move_lists(struct page_cgroup *pc, bool active) { if (active) list_move(&pc->lru, &pc->mem_cgroup->active_list); @@ -365,6 +377,22 @@ err: return -ENOMEM; } +/* + * See if the cached pages should be charged at all? + */ +int mem_cgroup_cache_charge(struct page *page, struct mm_struct *mm) +{ + struct mem_cgroup *mem; + if (!mm) + mm = &init_mm; + + mem = rcu_dereference(mm->mem_cgroup); + if (mem->control_type == MEM_CGROUP_TYPE_ALL) + return mem_cgroup_charge(page, mm); + else + return 0; +} + /* * Uncharging is always a welcome operation, we never complain, simply * uncharge. @@ -375,6 +403,10 @@ void mem_cgroup_uncharge(struct page_cgroup *pc) struct page *page; unsigned long flags; + /* + * This can handle cases when a page is not charged at all and we + * are switching between handling the control_type. + */ if (!pc) return; @@ -425,6 +457,60 @@ static ssize_t mem_cgroup_write(struct cgroup *cont, struct cftype *cft, mem_cgroup_write_strategy); } +static ssize_t mem_control_type_write(struct cgroup *cont, + struct cftype *cft, struct file *file, + const char __user *userbuf, + size_t nbytes, loff_t *pos) +{ + int ret; + char *buf, *end; + unsigned long tmp; + struct mem_cgroup *mem; + + mem = mem_cgroup_from_cont(cont); + buf = kmalloc(nbytes + 1, GFP_KERNEL); + ret = -ENOMEM; + if (buf == NULL) + goto out; + + buf[nbytes] = 0; + ret = -EFAULT; + if (copy_from_user(buf, userbuf, nbytes)) + goto out_free; + + ret = -EINVAL; + tmp = simple_strtoul(buf, &end, 10); + if (*end != '\0') + goto out_free; + + if (tmp <= MEM_CGROUP_TYPE_UNSPEC || tmp >= MEM_CGROUP_TYPE_MAX) + goto out_free; + + mem->control_type = tmp; + ret = nbytes; +out_free: + kfree(buf); +out: + return ret; +} + +static ssize_t mem_control_type_read(struct cgroup *cont, + struct cftype *cft, + struct file *file, char __user *userbuf, + size_t nbytes, loff_t *ppos) +{ + unsigned long val; + char buf[64], *s; + struct mem_cgroup *mem; + + mem = mem_cgroup_from_cont(cont); + s = buf; + val = mem->control_type; + s += sprintf(s, "%lu\n", val); + return simple_read_from_buffer((void __user *)userbuf, nbytes, + ppos, buf, s - buf); +} + static struct cftype mem_cgroup_files[] = { { .name = "usage_in_bytes", @@ -442,6 +528,11 @@ static struct cftype mem_cgroup_files[] = { .private = RES_FAILCNT, .read = mem_cgroup_read, }, + { + .name = "control_type", + .write = mem_control_type_write, + .read = mem_control_type_read, + }, }; static struct mem_cgroup init_mem_cgroup; @@ -464,6 +555,7 @@ mem_cgroup_create(struct cgroup_subsys *ss, struct cgroup *cont) INIT_LIST_HEAD(&mem->active_list); INIT_LIST_HEAD(&mem->inactive_list); spin_lock_init(&mem->lru_lock); + mem->control_type = MEM_CGROUP_TYPE_ALL; return &mem->css; } diff --git a/mm/swap_state.c b/mm/swap_state.c index f96e3ff1e79..88258869c8e 100644 --- a/mm/swap_state.c +++ b/mm/swap_state.c @@ -78,7 +78,7 @@ int add_to_swap_cache(struct page *page, swp_entry_t entry, gfp_t gfp_mask) error = radix_tree_preload(gfp_mask); if (!error) { - error = mem_cgroup_charge(page, current->mm); + error = mem_cgroup_cache_charge(page, current->mm); if (error) goto out;