Now that the external page_cgroup data structure and its lookup is
gone, the only code remaining in there is swap slot accounting.
Rename it and move the conditional compilation into mm/Makefile.
Signed-off-by: Johannes Weiner <hannes@xxxxxxxxxxx>
---
MAINTAINERS | 2 +-
include/linux/page_cgroup.h | 40 ---------
include/linux/swap_cgroup.h | 42 +++++++++
mm/Makefile | 3 +-
mm/memcontrol.c | 2 +-
mm/page_cgroup.c | 211 --------------------------------------------
mm/swap_cgroup.c | 208 +++++++++++++++++++++++++++++++++++++++++++
mm/swap_state.c | 1 -
mm/swapfile.c | 2 +-
9 files changed, 255 insertions(+), 256 deletions(-)
delete mode 100644 include/linux/page_cgroup.h
create mode 100644 include/linux/swap_cgroup.h
delete mode 100644 mm/page_cgroup.c
create mode 100644 mm/swap_cgroup.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 7e31be07197e..3a60389d3a13 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -2583,7 +2583,7 @@ L: cgroups@xxxxxxxxxxxxxxx
L: linux-mm@xxxxxxxxx
S: Maintained
F: mm/memcontrol.c
-F: mm/page_cgroup.c
+F: mm/swap_cgroup.c
CORETEMP HARDWARE MONITORING DRIVER
M: Fenghua Yu <fenghua.yu@xxxxxxxxx>
diff --git a/include/linux/page_cgroup.h b/include/linux/page_cgroup.h
deleted file mode 100644
index 65be35785c86..000000000000
--- a/include/linux/page_cgroup.h
+++ /dev/null
@@ -1,40 +0,0 @@
-#ifndef __LINUX_PAGE_CGROUP_H
-#define __LINUX_PAGE_CGROUP_H
-
-#include <linux/swap.h>
-
-#ifdef CONFIG_MEMCG_SWAP
-extern unsigned short swap_cgroup_cmpxchg(swp_entry_t ent,
- unsigned short old, unsigned short new);
-extern unsigned short swap_cgroup_record(swp_entry_t ent, unsigned short id);
-extern unsigned short lookup_swap_cgroup_id(swp_entry_t ent);
-extern int swap_cgroup_swapon(int type, unsigned long max_pages);
-extern void swap_cgroup_swapoff(int type);
-#else
-
-static inline
-unsigned short swap_cgroup_record(swp_entry_t ent, unsigned short id)
-{
- return 0;
-}
-
-static inline
-unsigned short lookup_swap_cgroup_id(swp_entry_t ent)
-{
- return 0;
-}
-
-static inline int
-swap_cgroup_swapon(int type, unsigned long max_pages)
-{
- return 0;
-}
-
-static inline void swap_cgroup_swapoff(int type)
-{
- return;
-}
-
-#endif /* CONFIG_MEMCG_SWAP */
-
-#endif /* __LINUX_PAGE_CGROUP_H */
diff --git a/include/linux/swap_cgroup.h b/include/linux/swap_cgroup.h
new file mode 100644
index 000000000000..145306bdc92f
--- /dev/null
+++ b/include/linux/swap_cgroup.h
@@ -0,0 +1,42 @@
+#ifndef __LINUX_SWAP_CGROUP_H
+#define __LINUX_SWAP_CGROUP_H
+
+#include <linux/swap.h>
+
+#ifdef CONFIG_MEMCG_SWAP
+
+extern unsigned short swap_cgroup_cmpxchg(swp_entry_t ent,
+ unsigned short old, unsigned short new);
+extern unsigned short swap_cgroup_record(swp_entry_t ent, unsigned short id);
+extern unsigned short lookup_swap_cgroup_id(swp_entry_t ent);
+extern int swap_cgroup_swapon(int type, unsigned long max_pages);
+extern void swap_cgroup_swapoff(int type);
+
+#else
+
+static inline
+unsigned short swap_cgroup_record(swp_entry_t ent, unsigned short id)
+{
+ return 0;
+}
+
+static inline
+unsigned short lookup_swap_cgroup_id(swp_entry_t ent)
+{
+ return 0;
+}
+
+static inline int
+swap_cgroup_swapon(int type, unsigned long max_pages)
+{
+ return 0;
+}
+
+static inline void swap_cgroup_swapoff(int type)
+{
+ return;
+}
+
+#endif /* CONFIG_MEMCG_SWAP */
+
+#endif /* __LINUX_SWAP_CGROUP_H */
diff --git a/mm/Makefile b/mm/Makefile
index 27ddb80403a9..d9d579484f15 100644
--- a/mm/Makefile
+++ b/mm/Makefile
@@ -56,7 +56,8 @@ obj-$(CONFIG_MIGRATION) += migrate.o
obj-$(CONFIG_QUICKLIST) += quicklist.o
obj-$(CONFIG_TRANSPARENT_HUGEPAGE) += huge_memory.o
obj-$(CONFIG_PAGE_COUNTER) += page_counter.o
-obj-$(CONFIG_MEMCG) += memcontrol.o page_cgroup.o vmpressure.o
+obj-$(CONFIG_MEMCG) += memcontrol.o vmpressure.o
+obj-$(CONFIG_MEMCG_SWAP) += swap_cgroup.o
obj-$(CONFIG_CGROUP_HUGETLB) += hugetlb_cgroup.o
obj-$(CONFIG_MEMORY_FAILURE) += memory-failure.o
obj-$(CONFIG_HWPOISON_INJECT) += hwpoison-inject.o
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index dc5e0abb18cb..fbb41a170eae 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -51,7 +51,7 @@
#include <linux/seq_file.h>
#include <linux/vmpressure.h>
#include <linux/mm_inline.h>
-#include <linux/page_cgroup.h>
+#include <linux/swap_cgroup.h>
#include <linux/cpu.h>
#include <linux/oom.h>
#include <linux/lockdep.h>
diff --git a/mm/page_cgroup.c b/mm/page_cgroup.c
deleted file mode 100644
index f0f31c1d4d0c..000000000000
--- a/mm/page_cgroup.c
+++ /dev/null
@@ -1,211 +0,0 @@
-#include <linux/mm.h>
-#include <linux/page_cgroup.h>
-#include <linux/vmalloc.h>
-#include <linux/swapops.h>
-
-#ifdef CONFIG_MEMCG_SWAP
-
-static DEFINE_MUTEX(swap_cgroup_mutex);
-struct swap_cgroup_ctrl {
- struct page **map;
- unsigned long length;
- spinlock_t lock;
-};
-
-static 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))
-
-/*
- * 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;
-}
-
-static struct swap_cgroup *lookup_swap_cgroup(swp_entry_t ent,
- struct swap_cgroup_ctrl **ctrlp)
-{
- pgoff_t offset = swp_offset(ent);
- struct swap_cgroup_ctrl *ctrl;
- struct page *mappage;
- struct swap_cgroup *sc;
-
- ctrl = &swap_cgroup_ctrl[swp_type(ent)];
- if (ctrlp)
- *ctrlp = ctrl;
-
- mappage = ctrl->map[offset / SC_PER_PAGE];
- sc = page_address(mappage);
- return sc + offset % SC_PER_PAGE;
-}
-
-/**
- * swap_cgroup_cmpxchg - cmpxchg mem_cgroup's id for this swp_entry.
- * @ent: 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)
-{
- struct swap_cgroup_ctrl *ctrl;
- struct swap_cgroup *sc;
- unsigned long flags;
- unsigned short retval;
-
- sc = lookup_swap_cgroup(ent, &ctrl);
-
- 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
- * @id: 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)
-{
- struct swap_cgroup_ctrl *ctrl;
- struct swap_cgroup *sc;
- unsigned short old;
- unsigned long flags;
-
- sc = lookup_swap_cgroup(ent, &ctrl);
-
- spin_lock_irqsave(&ctrl->lock, flags);
- old = sc->id;
- sc->id = id;
- spin_unlock_irqrestore(&ctrl->lock, flags);
-
- return old;
-}
-
-/**
- * lookup_swap_cgroup_id - lookup mem_cgroup id tied to swap entry
- * @ent: swap entry to be looked up.
- *
- * Returns ID of mem_cgroup at success. 0 at failure. (0 is invalid ID)
- */
-unsigned short lookup_swap_cgroup_id(swp_entry_t ent)
-{
- return lookup_swap_cgroup(ent, NULL)->id;
-}
-
-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 = DIV_ROUND_UP(max_pages, SC_PER_PAGE);
- array_size = length * sizeof(void *);
-
- array = vzalloc(array_size);
- if (!array)
- goto nomem;
-
- 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;
- mutex_unlock(&swap_cgroup_mutex);
- vfree(array);
- 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 swapaccount=0 boot option\n");
- return -ENOMEM;
-}
-
-void swap_cgroup_swapoff(int type)
-{
- struct page **map;
- unsigned long i, length;
- struct swap_cgroup_ctrl *ctrl;
-
- if (!do_swap_account)
- return;
-
- mutex_lock(&swap_cgroup_mutex);
- ctrl = &swap_cgroup_ctrl[type];
- map = ctrl->map;
- length = ctrl->length;
- ctrl->map = NULL;
- ctrl->length = 0;
- mutex_unlock(&swap_cgroup_mutex);
-
- if (map) {
- for (i = 0; i < length; i++) {
- struct page *page = map[i];
- if (page)
- __free_page(page);
- }
- vfree(map);
- }
-}
-
-#endif
diff --git a/mm/swap_cgroup.c b/mm/swap_cgroup.c
new file mode 100644
index 000000000000..b5f7f24b8dd1
--- /dev/null
+++ b/mm/swap_cgroup.c
@@ -0,0 +1,208 @@
+#include <linux/swap_cgroup.h>
+#include <linux/vmalloc.h>
+#include <linux/mm.h>
+
+#include <linux/swapops.h> /* depends on mm.h include */
+
+static DEFINE_MUTEX(swap_cgroup_mutex);
+struct swap_cgroup_ctrl {
+ struct page **map;
+ unsigned long length;
+ spinlock_t lock;
+};
+
+static 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))
+
+/*
+ * 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;
+}
+
+static struct swap_cgroup *lookup_swap_cgroup(swp_entry_t ent,
+ struct swap_cgroup_ctrl **ctrlp)
+{
+ pgoff_t offset = swp_offset(ent);
+ struct swap_cgroup_ctrl *ctrl;
+ struct page *mappage;
+ struct swap_cgroup *sc;
+
+ ctrl = &swap_cgroup_ctrl[swp_type(ent)];
+ if (ctrlp)
+ *ctrlp = ctrl;
+
+ mappage = ctrl->map[offset / SC_PER_PAGE];
+ sc = page_address(mappage);
+ return sc + offset % SC_PER_PAGE;
+}
+
+/**
+ * swap_cgroup_cmpxchg - cmpxchg mem_cgroup's id for this swp_entry.
+ * @ent: 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)
+{
+ struct swap_cgroup_ctrl *ctrl;
+ struct swap_cgroup *sc;
+ unsigned long flags;
+ unsigned short retval;
+
+ sc = lookup_swap_cgroup(ent, &ctrl);
+
+ 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
+ * @id: 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)
+{
+ struct swap_cgroup_ctrl *ctrl;
+ struct swap_cgroup *sc;
+ unsigned short old;
+ unsigned long flags;
+
+ sc = lookup_swap_cgroup(ent, &ctrl);
+
+ spin_lock_irqsave(&ctrl->lock, flags);
+ old = sc->id;
+ sc->id = id;
+ spin_unlock_irqrestore(&ctrl->lock, flags);
+
+ return old;
+}
+
+/**
+ * lookup_swap_cgroup_id - lookup mem_cgroup id tied to swap entry
+ * @ent: swap entry to be looked up.
+ *
+ * Returns ID of mem_cgroup at success. 0 at failure. (0 is invalid ID)
+ */
+unsigned short lookup_swap_cgroup_id(swp_entry_t ent)
+{
+ return lookup_swap_cgroup(ent, NULL)->id;
+}
+
+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 = DIV_ROUND_UP(max_pages, SC_PER_PAGE);
+ array_size = length * sizeof(void *);
+
+ array = vzalloc(array_size);
+ if (!array)
+ goto nomem;
+
+ 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;
+ mutex_unlock(&swap_cgroup_mutex);
+ vfree(array);
+ 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 swapaccount=0 boot option\n");
+ return -ENOMEM;
+}
+
+void swap_cgroup_swapoff(int type)
+{
+ struct page **map;
+ unsigned long i, length;
+ struct swap_cgroup_ctrl *ctrl;
+
+ if (!do_swap_account)
+ return;
+
+ mutex_lock(&swap_cgroup_mutex);
+ ctrl = &swap_cgroup_ctrl[type];
+ map = ctrl->map;
+ length = ctrl->length;
+ ctrl->map = NULL;
+ ctrl->length = 0;
+ mutex_unlock(&swap_cgroup_mutex);
+
+ if (map) {
+ for (i = 0; i < length; i++) {
+ struct page *page = map[i];
+ if (page)
+ __free_page(page);
+ }
+ vfree(map);
+ }
+}
diff --git a/mm/swap_state.c b/mm/swap_state.c
index 154444918685..9711342987a0 100644
--- a/mm/swap_state.c
+++ b/mm/swap_state.c
@@ -17,7 +17,6 @@
#include <linux/blkdev.h>
#include <linux/pagevec.h>
#include <linux/migrate.h>
-#include <linux/page_cgroup.h>
#include <asm/pgtable.h>
diff --git a/mm/swapfile.c b/mm/swapfile.c
index 8798b2e0ac59..63f55ccb9b26 100644
--- a/mm/swapfile.c
+++ b/mm/swapfile.c
@@ -38,7 +38,7 @@
#include <asm/pgtable.h>
#include <asm/tlbflush.h>
#include <linux/swapops.h>
-#include <linux/page_cgroup.h>
+#include <linux/swap_cgroup.h>
static bool swap_count_continued(struct swap_info_struct *, pgoff_t,
unsigned char);
--
2.1.3
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