X-Git-Url: http://pileus.org/git/?a=blobdiff_plain;f=mm%2Fswapfile.c;h=de5bc51c4a66aa8d24fa14ee5e3dbe5542999c18;hb=9800ee6f50a3b94181d4df57542b9379e331decb;hp=457b10baef59414f591fb0bfab2b54619c5209b0;hpb=7e1bd6e38b1f30860ce25a014c6d6adfb0079f4a;p=~andy%2Flinux diff --git a/mm/swapfile.c b/mm/swapfile.c index 457b10baef5..de5bc51c4a6 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -31,6 +31,8 @@ #include #include #include +#include +#include #include #include @@ -42,7 +44,7 @@ static bool swap_count_continued(struct swap_info_struct *, pgoff_t, static void free_swap_count_continuations(struct swap_info_struct *); static sector_t map_swap_entry(swp_entry_t, struct block_device**); -static DEFINE_SPINLOCK(swap_lock); +DEFINE_SPINLOCK(swap_lock); static unsigned int nr_swapfiles; long nr_swap_pages; long total_swap_pages; @@ -53,9 +55,9 @@ static const char Unused_file[] = "Unused swap file entry "; static const char Bad_offset[] = "Bad swap offset entry "; static const char Unused_offset[] = "Unused swap offset entry "; -static struct swap_list_t swap_list = {-1, -1}; +struct swap_list_t swap_list = {-1, -1}; -static struct swap_info_struct *swap_info[MAX_SWAPFILES]; +struct swap_info_struct *swap_info[MAX_SWAPFILES]; static DEFINE_MUTEX(swapon_mutex); @@ -556,6 +558,7 @@ static unsigned char swap_entry_free(struct swap_info_struct *p, swap_list.next = p->type; nr_swap_pages++; p->inuse_pages--; + frontswap_invalidate_page(p->type, offset); if ((p->flags & SWP_BLKDEV) && disk->fops->swap_slot_free_notify) disk->fops->swap_slot_free_notify(p->bdev, offset); @@ -985,11 +988,12 @@ static int unuse_mm(struct mm_struct *mm, } /* - * Scan swap_map from current position to next entry still in use. + * Scan swap_map (or frontswap_map if frontswap parameter is true) + * from current position to next entry still in use. * Recycle to start on reaching the end, returning 0 when empty. */ static unsigned int find_next_to_unuse(struct swap_info_struct *si, - unsigned int prev) + unsigned int prev, bool frontswap) { unsigned int max = si->max; unsigned int i = prev; @@ -1015,6 +1019,12 @@ static unsigned int find_next_to_unuse(struct swap_info_struct *si, prev = 0; i = 1; } + if (frontswap) { + if (frontswap_test(si, i)) + break; + else + continue; + } count = si->swap_map[i]; if (count && swap_count(count) != SWAP_MAP_BAD) break; @@ -1026,8 +1036,12 @@ static unsigned int find_next_to_unuse(struct swap_info_struct *si, * We completely avoid races by reading each swap page in advance, * and then search for the process using it. All the necessary * page table adjustments can then be made atomically. + * + * if the boolean frontswap is true, only unuse pages_to_unuse pages; + * pages_to_unuse==0 means all pages; ignored if frontswap is false */ -static int try_to_unuse(unsigned int type) +int try_to_unuse(unsigned int type, bool frontswap, + unsigned long pages_to_unuse) { struct swap_info_struct *si = swap_info[type]; struct mm_struct *start_mm; @@ -1060,7 +1074,7 @@ static int try_to_unuse(unsigned int type) * one pass through swap_map is enough, but not necessarily: * there are races when an instance of an entry might be missed. */ - while ((i = find_next_to_unuse(si, i)) != 0) { + while ((i = find_next_to_unuse(si, i, frontswap)) != 0) { if (signal_pending(current)) { retval = -EINTR; break; @@ -1227,6 +1241,10 @@ static int try_to_unuse(unsigned int type) * interactive performance. */ cond_resched(); + if (frontswap && pages_to_unuse > 0) { + if (!--pages_to_unuse) + break; + } } mmput(start_mm); @@ -1486,7 +1504,8 @@ bad_bmap: } static void enable_swap_info(struct swap_info_struct *p, int prio, - unsigned char *swap_map) + unsigned char *swap_map, + unsigned long *frontswap_map) { int i, prev; @@ -1496,6 +1515,7 @@ static void enable_swap_info(struct swap_info_struct *p, int prio, else p->prio = --least_priority; p->swap_map = swap_map; + frontswap_map_set(p, frontswap_map); p->flags |= SWP_WRITEOK; nr_swap_pages += p->pages; total_swap_pages += p->pages; @@ -1512,6 +1532,7 @@ static void enable_swap_info(struct swap_info_struct *p, int prio, swap_list.head = swap_list.next = p->type; else swap_info[prev]->next = p->type; + frontswap_init(p->type); spin_unlock(&swap_lock); } @@ -1585,7 +1606,7 @@ SYSCALL_DEFINE1(swapoff, const char __user *, specialfile) spin_unlock(&swap_lock); oom_score_adj = test_set_oom_score_adj(OOM_SCORE_ADJ_MAX); - err = try_to_unuse(type); + err = try_to_unuse(type, false, 0); /* force all pages to be unused */ compare_swap_oom_score_adj(OOM_SCORE_ADJ_MAX, oom_score_adj); if (err) { @@ -1596,7 +1617,7 @@ SYSCALL_DEFINE1(swapoff, const char __user *, specialfile) * sys_swapoff for this swap_info_struct at this point. */ /* re-insert swap space back into swap_list */ - enable_swap_info(p, p->prio, p->swap_map); + enable_swap_info(p, p->prio, p->swap_map, frontswap_map_get(p)); goto out_dput; } @@ -1622,9 +1643,11 @@ SYSCALL_DEFINE1(swapoff, const char __user *, specialfile) swap_map = p->swap_map; p->swap_map = NULL; p->flags = 0; + frontswap_invalidate_area(type); spin_unlock(&swap_lock); mutex_unlock(&swapon_mutex); vfree(swap_map); + vfree(frontswap_map_get(p)); /* Destroy swap account informatin */ swap_cgroup_swapoff(type); @@ -1988,6 +2011,7 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags) sector_t span; unsigned long maxpages; unsigned char *swap_map = NULL; + unsigned long *frontswap_map = NULL; struct page *page = NULL; struct inode *inode = NULL; @@ -2071,6 +2095,9 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags) error = nr_extents; goto bad_swap; } + /* frontswap enabled? set up bit-per-page map for frontswap */ + if (frontswap_enabled) + frontswap_map = vzalloc(maxpages / sizeof(long)); if (p->bdev) { if (blk_queue_nonrot(bdev_get_queue(p->bdev))) { @@ -2086,14 +2113,15 @@ SYSCALL_DEFINE2(swapon, const char __user *, specialfile, int, swap_flags) if (swap_flags & SWAP_FLAG_PREFER) prio = (swap_flags & SWAP_FLAG_PRIO_MASK) >> SWAP_FLAG_PRIO_SHIFT; - enable_swap_info(p, prio, swap_map); + enable_swap_info(p, prio, swap_map, frontswap_map); printk(KERN_INFO "Adding %uk swap on %s. " - "Priority:%d extents:%d across:%lluk %s%s\n", + "Priority:%d extents:%d across:%lluk %s%s%s\n", p->pages<<(PAGE_SHIFT-10), name, p->prio, nr_extents, (unsigned long long)span<<(PAGE_SHIFT-10), (p->flags & SWP_SOLIDSTATE) ? "SS" : "", - (p->flags & SWP_DISCARDABLE) ? "D" : ""); + (p->flags & SWP_DISCARDABLE) ? "D" : "", + (frontswap_map) ? "FS" : ""); mutex_unlock(&swapon_mutex); atomic_inc(&proc_poll_event);