diff options
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/Kconfig | 23 | ||||
| -rw-r--r-- | mm/Makefile | 1 | ||||
| -rw-r--r-- | mm/cleancache.c | 244 | ||||
| -rw-r--r-- | mm/filemap.c | 11 | ||||
| -rw-r--r-- | mm/fremap.c | 2 | ||||
| -rw-r--r-- | mm/hugetlb.c | 4 | ||||
| -rw-r--r-- | mm/memory.c | 2 | ||||
| -rw-r--r-- | mm/mlock.c | 8 | ||||
| -rw-r--r-- | mm/mmap.c | 8 | ||||
| -rw-r--r-- | mm/slub.c | 1 | ||||
| -rw-r--r-- | mm/truncate.c | 6 |
11 files changed, 297 insertions, 13 deletions
diff --git a/mm/Kconfig b/mm/Kconfig index e9c0c61f2ddd..8ca47a5ee9c8 100644 --- a/mm/Kconfig +++ b/mm/Kconfig @@ -347,3 +347,26 @@ config NEED_PER_CPU_KM depends on !SMP bool default y + +config CLEANCACHE + bool "Enable cleancache driver to cache clean pages if tmem is present" + default n + help + Cleancache can be thought of as a page-granularity victim cache + for clean pages that the kernel's pageframe replacement algorithm + (PFRA) would like to keep around, but can't since there isn't enough + memory. So when the PFRA "evicts" a page, it first attempts to use + cleancacne code to put the data contained in that page into + "transcendent memory", memory that is not directly accessible or + addressable by the kernel and is of unknown and possibly + time-varying size. And when a cleancache-enabled + filesystem wishes to access a page in a file on disk, it first + checks cleancache to see if it already contains it; if it does, + the page is copied into the kernel and a disk access is avoided. + When a transcendent memory driver is available (such as zcache or + Xen transcendent memory), a significant I/O reduction + may be achieved. When none is available, all cleancache calls + are reduced to a single pointer-compare-against-NULL resulting + in a negligible performance hit. + + If unsure, say Y to enable cleancache diff --git a/mm/Makefile b/mm/Makefile index 42a8326c3e3d..836e4163c1bf 100644 --- a/mm/Makefile +++ b/mm/Makefile @@ -49,3 +49,4 @@ obj-$(CONFIG_MEMORY_FAILURE) += memory-failure.o obj-$(CONFIG_HWPOISON_INJECT) += hwpoison-inject.o obj-$(CONFIG_DEBUG_KMEMLEAK) += kmemleak.o obj-$(CONFIG_DEBUG_KMEMLEAK_TEST) += kmemleak-test.o +obj-$(CONFIG_CLEANCACHE) += cleancache.o diff --git a/mm/cleancache.c b/mm/cleancache.c new file mode 100644 index 000000000000..bcaae4c2a770 --- /dev/null +++ b/mm/cleancache.c @@ -0,0 +1,244 @@ +/* + * Cleancache frontend + * + * This code provides the generic "frontend" layer to call a matching + * "backend" driver implementation of cleancache. See + * Documentation/vm/cleancache.txt for more information. + * + * Copyright (C) 2009-2010 Oracle Corp. All rights reserved. + * Author: Dan Magenheimer + * + * This work is licensed under the terms of the GNU GPL, version 2. + */ + +#include <linux/module.h> +#include <linux/fs.h> +#include <linux/exportfs.h> +#include <linux/mm.h> +#include <linux/cleancache.h> + +/* + * This global enablement flag may be read thousands of times per second + * by cleancache_get/put/flush even on systems where cleancache_ops + * is not claimed (e.g. cleancache is config'ed on but remains + * disabled), so is preferred to the slower alternative: a function + * call that checks a non-global. + */ +int cleancache_enabled; +EXPORT_SYMBOL(cleancache_enabled); + +/* + * cleancache_ops is set by cleancache_ops_register to contain the pointers + * to the cleancache "backend" implementation functions. + */ +static struct cleancache_ops cleancache_ops; + +/* useful stats available in /sys/kernel/mm/cleancache */ +static unsigned long cleancache_succ_gets; +static unsigned long cleancache_failed_gets; +static unsigned long cleancache_puts; +static unsigned long cleancache_flushes; + +/* + * register operations for cleancache, returning previous thus allowing + * detection of multiple backends and possible nesting + */ +struct cleancache_ops cleancache_register_ops(struct cleancache_ops *ops) +{ + struct cleancache_ops old = cleancache_ops; + + cleancache_ops = *ops; + cleancache_enabled = 1; + return old; +} +EXPORT_SYMBOL(cleancache_register_ops); + +/* Called by a cleancache-enabled filesystem at time of mount */ +void __cleancache_init_fs(struct super_block *sb) +{ + sb->cleancache_poolid = (*cleancache_ops.init_fs)(PAGE_SIZE); +} +EXPORT_SYMBOL(__cleancache_init_fs); + +/* Called by a cleancache-enabled clustered filesystem at time of mount */ +void __cleancache_init_shared_fs(char *uuid, struct super_block *sb) +{ + sb->cleancache_poolid = + (*cleancache_ops.init_shared_fs)(uuid, PAGE_SIZE); +} +EXPORT_SYMBOL(__cleancache_init_shared_fs); + +/* + * If the filesystem uses exportable filehandles, use the filehandle as + * the key, else use the inode number. + */ +static int cleancache_get_key(struct inode *inode, + struct cleancache_filekey *key) +{ + int (*fhfn)(struct dentry *, __u32 *fh, int *, int); + int len = 0, maxlen = CLEANCACHE_KEY_MAX; + struct super_block *sb = inode->i_sb; + + key->u.ino = inode->i_ino; + if (sb->s_export_op != NULL) { + fhfn = sb->s_export_op->encode_fh; + if (fhfn) { + struct dentry d; + d.d_inode = inode; + len = (*fhfn)(&d, &key->u.fh[0], &maxlen, 0); + if (len <= 0 || len == 255) + return -1; + if (maxlen > CLEANCACHE_KEY_MAX) + return -1; + } + } + return 0; +} + +/* + * "Get" data from cleancache associated with the poolid/inode/index + * that were specified when the data was put to cleanache and, if + * successful, use it to fill the specified page with data and return 0. + * The pageframe is unchanged and returns -1 if the get fails. + * Page must be locked by caller. + */ +int __cleancache_get_page(struct page *page) +{ + int ret = -1; + int pool_id; + struct cleancache_filekey key = { .u.key = { 0 } }; + + VM_BUG_ON(!PageLocked(page)); + pool_id = page->mapping->host->i_sb->cleancache_poolid; + if (pool_id < 0) + goto out; + + if (cleancache_get_key(page->mapping->host, &key) < 0) + goto out; + + ret = (*cleancache_ops.get_page)(pool_id, key, page->index, page); + if (ret == 0) + cleancache_succ_gets++; + else + cleancache_failed_gets++; +out: + return ret; +} +EXPORT_SYMBOL(__cleancache_get_page); + +/* + * "Put" data from a page to cleancache and associate it with the + * (previously-obtained per-filesystem) poolid and the page's, + * inode and page index. Page must be locked. Note that a put_page + * always "succeeds", though a subsequent get_page may succeed or fail. + */ +void __cleancache_put_page(struct page *page) +{ + int pool_id; + struct cleancache_filekey key = { .u.key = { 0 } }; + + VM_BUG_ON(!PageLocked(page)); + pool_id = page->mapping->host->i_sb->cleancache_poolid; + if (pool_id >= 0 && + cleancache_get_key(page->mapping->host, &key) >= 0) { + (*cleancache_ops.put_page)(pool_id, key, page->index, page); + cleancache_puts++; + } +} +EXPORT_SYMBOL(__cleancache_put_page); + +/* + * Flush any data from cleancache associated with the poolid and the + * page's inode and page index so that a subsequent "get" will fail. + */ +void __cleancache_flush_page(struct address_space *mapping, struct page *page) +{ + /* careful... page->mapping is NULL sometimes when this is called */ + int pool_id = mapping->host->i_sb->cleancache_poolid; + struct cleancache_filekey key = { .u.key = { 0 } }; + + if (pool_id >= 0) { + VM_BUG_ON(!PageLocked(page)); + if (cleancache_get_key(mapping->host, &key) >= 0) { + (*cleancache_ops.flush_page)(pool_id, key, page->index); + cleancache_flushes++; + } + } +} +EXPORT_SYMBOL(__cleancache_flush_page); + +/* + * Flush all data from cleancache associated with the poolid and the + * mappings's inode so that all subsequent gets to this poolid/inode + * will fail. + */ +void __cleancache_flush_inode(struct address_space *mapping) +{ + int pool_id = mapping->host->i_sb->cleancache_poolid; + struct cleancache_filekey key = { .u.key = { 0 } }; + + if (pool_id >= 0 && cleancache_get_key(mapping->host, &key) >= 0) + (*cleancache_ops.flush_inode)(pool_id, key); +} +EXPORT_SYMBOL(__cleancache_flush_inode); + +/* + * Called by any cleancache-enabled filesystem at time of unmount; + * note that pool_id is surrendered and may be reutrned by a subsequent + * cleancache_init_fs or cleancache_init_shared_fs + */ +void __cleancache_flush_fs(struct super_block *sb) +{ + if (sb->cleancache_poolid >= 0) { + int old_poolid = sb->cleancache_poolid; + sb->cleancache_poolid = -1; + (*cleancache_ops.flush_fs)(old_poolid); + } +} +EXPORT_SYMBOL(__cleancache_flush_fs); + +#ifdef CONFIG_SYSFS + +/* see Documentation/ABI/xxx/sysfs-kernel-mm-cleancache */ + +#define CLEANCACHE_SYSFS_RO(_name) \ + static ssize_t cleancache_##_name##_show(struct kobject *kobj, \ + struct kobj_attribute *attr, char *buf) \ + { \ + return sprintf(buf, "%lu\n", cleancache_##_name); \ + } \ + static struct kobj_attribute cleancache_##_name##_attr = { \ + .attr = { .name = __stringify(_name), .mode = 0444 }, \ + .show = cleancache_##_name##_show, \ + } + +CLEANCACHE_SYSFS_RO(succ_gets); +CLEANCACHE_SYSFS_RO(failed_gets); +CLEANCACHE_SYSFS_RO(puts); +CLEANCACHE_SYSFS_RO(flushes); + +static struct attribute *cleancache_attrs[] = { + &cleancache_succ_gets_attr.attr, + &cleancache_failed_gets_attr.attr, + &cleancache_puts_attr.attr, + &cleancache_flushes_attr.attr, + NULL, +}; + +static struct attribute_group cleancache_attr_group = { + .attrs = cleancache_attrs, + .name = "cleancache", +}; + +#endif /* CONFIG_SYSFS */ + +static int __init init_cleancache(void) +{ +#ifdef CONFIG_SYSFS + int err; + + err = sysfs_create_group(mm_kobj, &cleancache_attr_group); +#endif /* CONFIG_SYSFS */ + return 0; +} +module_init(init_cleancache) diff --git a/mm/filemap.c b/mm/filemap.c index 68e782b3d3de..7455ccd8bda8 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -34,6 +34,7 @@ #include <linux/hardirq.h> /* for BUG_ON(!in_atomic()) only */ #include <linux/memcontrol.h> #include <linux/mm_inline.h> /* for page_is_file_cache() */ +#include <linux/cleancache.h> #include "internal.h" /* @@ -118,6 +119,16 @@ void __delete_from_page_cache(struct page *page) { struct address_space *mapping = page->mapping; + /* + * if we're uptodate, flush out into the cleancache, otherwise + * invalidate any existing cleancache entries. We can't leave + * stale data around in the cleancache once our page is gone + */ + if (PageUptodate(page) && PageMappedToDisk(page)) + cleancache_put_page(page); + else + cleancache_flush_page(mapping, page); + radix_tree_delete(&mapping->page_tree, page->index); page->mapping = NULL; mapping->nrpages--; diff --git a/mm/fremap.c b/mm/fremap.c index 7f4123056e06..b8e0e2d468af 100644 --- a/mm/fremap.c +++ b/mm/fremap.c @@ -224,7 +224,7 @@ SYSCALL_DEFINE5(remap_file_pages, unsigned long, start, unsigned long, size, /* * drop PG_Mlocked flag for over-mapped range */ - unsigned int saved_flags = vma->vm_flags; + vm_flags_t saved_flags = vma->vm_flags; munlock_vma_pages_range(vma, start, start + size); vma->vm_flags = saved_flags; } diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 5fd68b95c671..f33bb319b73f 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -2833,7 +2833,7 @@ void hugetlb_change_protection(struct vm_area_struct *vma, int hugetlb_reserve_pages(struct inode *inode, long from, long to, struct vm_area_struct *vma, - int acctflag) + vm_flags_t vm_flags) { long ret, chg; struct hstate *h = hstate_inode(inode); @@ -2843,7 +2843,7 @@ int hugetlb_reserve_pages(struct inode *inode, * attempt will be made for VM_NORESERVE to allocate a page * and filesystem quota without using reserves */ - if (acctflag & VM_NORESERVE) + if (vm_flags & VM_NORESERVE) return 0; /* diff --git a/mm/memory.c b/mm/memory.c index b73f677f0bb1..fc24f7d788bd 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -730,7 +730,7 @@ static void print_bad_pte(struct vm_area_struct *vma, unsigned long addr, add_taint(TAINT_BAD_PAGE); } -static inline int is_cow_mapping(unsigned int flags) +static inline int is_cow_mapping(vm_flags_t flags) { return (flags & (VM_SHARED | VM_MAYWRITE)) == VM_MAYWRITE; } diff --git a/mm/mlock.c b/mm/mlock.c index 516b2c2ddd5a..048260c4e02e 100644 --- a/mm/mlock.c +++ b/mm/mlock.c @@ -307,13 +307,13 @@ void munlock_vma_pages_range(struct vm_area_struct *vma, * For vmas that pass the filters, merge/split as appropriate. */ static int mlock_fixup(struct vm_area_struct *vma, struct vm_area_struct **prev, - unsigned long start, unsigned long end, unsigned int newflags) + unsigned long start, unsigned long end, vm_flags_t newflags) { struct mm_struct *mm = vma->vm_mm; pgoff_t pgoff; int nr_pages; int ret = 0; - int lock = newflags & VM_LOCKED; + int lock = !!(newflags & VM_LOCKED); if (newflags == vma->vm_flags || (vma->vm_flags & VM_SPECIAL) || is_vm_hugetlb_page(vma) || vma == get_gate_vma(current->mm)) @@ -385,7 +385,7 @@ static int do_mlock(unsigned long start, size_t len, int on) prev = vma; for (nstart = start ; ; ) { - unsigned int newflags; + vm_flags_t newflags; /* Here we know that vma->vm_start <= nstart < vma->vm_end. */ @@ -524,7 +524,7 @@ static int do_mlockall(int flags) goto out; for (vma = current->mm->mmap; vma ; vma = prev->vm_next) { - unsigned int newflags; + vm_flags_t newflags; newflags = vma->vm_flags | VM_LOCKED; if (!(flags & MCL_CURRENT)) diff --git a/mm/mmap.c b/mm/mmap.c index ac2631b7477f..bbdc9af5e117 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -960,7 +960,7 @@ unsigned long do_mmap_pgoff(struct file *file, unsigned long addr, { struct mm_struct * mm = current->mm; struct inode *inode; - unsigned int vm_flags; + vm_flags_t vm_flags; int error; unsigned long reqprot = prot; @@ -1165,7 +1165,7 @@ SYSCALL_DEFINE1(old_mmap, struct mmap_arg_struct __user *, arg) */ int vma_wants_writenotify(struct vm_area_struct *vma) { - unsigned int vm_flags = vma->vm_flags; + vm_flags_t vm_flags = vma->vm_flags; /* If it was private or non-writable, the write bit is already clear */ if ((vm_flags & (VM_WRITE|VM_SHARED)) != ((VM_WRITE|VM_SHARED))) @@ -1193,7 +1193,7 @@ int vma_wants_writenotify(struct vm_area_struct *vma) * We account for memory if it's a private writeable mapping, * not hugepages and VM_NORESERVE wasn't set. */ -static inline int accountable_mapping(struct file *file, unsigned int vm_flags) +static inline int accountable_mapping(struct file *file, vm_flags_t vm_flags) { /* * hugetlb has its own accounting separate from the core VM @@ -1207,7 +1207,7 @@ static inline int accountable_mapping(struct file *file, unsigned int vm_flags) unsigned long mmap_region(struct file *file, unsigned long addr, unsigned long len, unsigned long flags, - unsigned int vm_flags, unsigned long pgoff) + vm_flags_t vm_flags, unsigned long pgoff) { struct mm_struct *mm = current->mm; struct vm_area_struct *vma, *prev; diff --git a/mm/slub.c b/mm/slub.c index 4aad32d2e60d..7be0223531b0 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -1831,7 +1831,6 @@ load_freelist: page->inuse = page->objects; page->freelist = NULL; -unlock_out: slab_unlock(page); c->tid = next_tid(c->tid); local_irq_restore(flags); diff --git a/mm/truncate.c b/mm/truncate.c index a95667529135..3a29a6180212 100644 --- a/mm/truncate.c +++ b/mm/truncate.c @@ -19,6 +19,7 @@ #include <linux/task_io_accounting_ops.h> #include <linux/buffer_head.h> /* grr. try_to_release_page, do_invalidatepage */ +#include <linux/cleancache.h> #include "internal.h" @@ -51,6 +52,7 @@ void do_invalidatepage(struct page *page, unsigned long offset) static inline void truncate_partial_page(struct page *page, unsigned partial) { zero_user_segment(page, partial, PAGE_CACHE_SIZE); + cleancache_flush_page(page->mapping, page); if (page_has_private(page)) do_invalidatepage(page, partial); } @@ -214,6 +216,7 @@ void truncate_inode_pages_range(struct address_space *mapping, pgoff_t next; int i; + cleancache_flush_inode(mapping); if (mapping->nrpages == 0) return; @@ -291,6 +294,7 @@ void truncate_inode_pages_range(struct address_space *mapping, pagevec_release(&pvec); mem_cgroup_uncharge_end(); } + cleancache_flush_inode(mapping); } EXPORT_SYMBOL(truncate_inode_pages_range); @@ -440,6 +444,7 @@ int invalidate_inode_pages2_range(struct address_space *mapping, int did_range_unmap = 0; int wrapped = 0; + cleancache_flush_inode(mapping); pagevec_init(&pvec, 0); next = start; while (next <= end && !wrapped && @@ -498,6 +503,7 @@ int invalidate_inode_pages2_range(struct address_space *mapping, mem_cgroup_uncharge_end(); cond_resched(); } + cleancache_flush_inode(mapping); return ret; } EXPORT_SYMBOL_GPL(invalidate_inode_pages2_range); |