Expose checkpoint_dump_page() and restore_read_page() from memory.c. Also convert them to use a common scratch buffer in the ckpt_ctx to avoid alloc/dealloc on every page I/O (or group of them).
Signed-off-by: Dan Smith <[email protected]> --- checkpoint/memory.c | 29 ++++++++--------------------- checkpoint/sys.c | 8 ++++++++ include/linux/checkpoint.h | 3 +++ include/linux/checkpoint_types.h | 2 ++ 4 files changed, 21 insertions(+), 21 deletions(-) diff --git a/checkpoint/memory.c b/checkpoint/memory.c index ec3603a..9a4fe83 100644 --- a/checkpoint/memory.c +++ b/checkpoint/memory.c @@ -394,16 +394,15 @@ static int vma_fill_pgarr(struct ckpt_ctx *ctx, } /* dump contents of a pages: use kmap_atomic() to avoid TLB flush */ -static int checkpoint_dump_page(struct ckpt_ctx *ctx, - struct page *page, char *buf) +int checkpoint_dump_page(struct ckpt_ctx *ctx, struct page *page) { void *ptr; ptr = kmap_atomic(page, KM_USER1); - memcpy(buf, ptr, PAGE_SIZE); + memcpy(ctx->scratch_page, ptr, PAGE_SIZE); kunmap_atomic(ptr, KM_USER1); - return ckpt_kwrite(ctx, buf, PAGE_SIZE); + return ckpt_kwrite(ctx, ctx->scratch_page, PAGE_SIZE); } /** @@ -416,7 +415,6 @@ static int checkpoint_dump_page(struct ckpt_ctx *ctx, static int vma_dump_pages(struct ckpt_ctx *ctx, int total) { struct ckpt_pgarr *pgarr; - void *buf; int i, ret = 0; if (!total) @@ -434,19 +432,14 @@ static int vma_dump_pages(struct ckpt_ctx *ctx, int total) return ret; } - buf = (void *) __get_free_page(GFP_KERNEL); - if (!buf) - return -ENOMEM; - list_for_each_entry_reverse(pgarr, &ctx->pgarr_list, list) { for (i = 0; i < pgarr->nr_used; i++) { - ret = checkpoint_dump_page(ctx, pgarr->pages[i], buf); + ret = checkpoint_dump_page(ctx, pgarr->pages[i]); if (ret < 0) goto out; } } out: - free_page((unsigned long) buf); return ret; } @@ -889,17 +882,17 @@ static int read_pages_vaddrs(struct ckpt_ctx *ctx, unsigned long nr_pages) return 0; } -static int restore_read_page(struct ckpt_ctx *ctx, struct page *page, void *p) +int restore_read_page(struct ckpt_ctx *ctx, struct page *page) { void *ptr; int ret; - ret = ckpt_kread(ctx, p, PAGE_SIZE); + ret = ckpt_kread(ctx, ctx->scratch_page, PAGE_SIZE); if (ret < 0) return ret; ptr = kmap_atomic(page, KM_USER1); - memcpy(ptr, p, PAGE_SIZE); + memcpy(ptr, ctx->scratch_page, PAGE_SIZE); kunmap_atomic(ptr, KM_USER1); return 0; @@ -937,13 +930,8 @@ static int read_pages_contents(struct ckpt_ctx *ctx, struct inode *inode) { struct ckpt_pgarr *pgarr; unsigned long *vaddrs; - char *buf; int i, ret = 0; - buf = kmalloc(PAGE_SIZE, GFP_KERNEL); - if (!buf) - return -ENOMEM; - down_read(¤t->mm->mmap_sem); list_for_each_entry_reverse(pgarr, &ctx->pgarr_list, list) { vaddrs = pgarr->vaddrs; @@ -961,7 +949,7 @@ static int read_pages_contents(struct ckpt_ctx *ctx, struct inode *inode) goto out; } - ret = restore_read_page(ctx, page, buf); + ret = restore_read_page(ctx, page); page_cache_release(page); if (ret < 0) @@ -971,7 +959,6 @@ static int read_pages_contents(struct ckpt_ctx *ctx, struct inode *inode) out: up_read(¤t->mm->mmap_sem); - kfree(buf); return 0; } diff --git a/checkpoint/sys.c b/checkpoint/sys.c index baed891..88a8f25 100644 --- a/checkpoint/sys.c +++ b/checkpoint/sys.c @@ -246,6 +246,8 @@ static void ckpt_ctx_free(struct ckpt_ctx *ctx) sock_listening_list_free(&ctx->listen_sockets); + free_page((unsigned long)ctx->scratch_page); + kfree(ctx); } @@ -259,6 +261,12 @@ static struct ckpt_ctx *ckpt_ctx_alloc(int fd, unsigned long uflags, if (!ctx) return ERR_PTR(-ENOMEM); + ctx->scratch_page = (void *)__get_free_page(GFP_KERNEL); + if (!ctx->scratch_page) { + err = -ENOMEM; + goto err; + } + ctx->uflags = uflags; ctx->kflags = kflags; ctx->ktime_begin = ktime_get(); diff --git a/include/linux/checkpoint.h b/include/linux/checkpoint.h index 2bf7755..72a299e 100644 --- a/include/linux/checkpoint.h +++ b/include/linux/checkpoint.h @@ -94,6 +94,9 @@ extern int ckpt_read_consume(struct ckpt_ctx *ctx, int len, int type); extern char *ckpt_fill_fname(struct path *path, struct path *root, char *buf, int *len); +int checkpoint_dump_page(struct ckpt_ctx *ctx, struct page *page); +int restore_read_page(struct ckpt_ctx *ctx, struct page *page); + /* pids */ extern pid_t ckpt_pid_nr(struct ckpt_ctx *ctx, struct pid *pid); extern struct pid *_ckpt_find_pgrp(struct ckpt_ctx *ctx, pid_t pgid); diff --git a/include/linux/checkpoint_types.h b/include/linux/checkpoint_types.h index 79c9c09..c13532d 100644 --- a/include/linux/checkpoint_types.h +++ b/include/linux/checkpoint_types.h @@ -69,6 +69,8 @@ struct ckpt_ctx { struct list_head pgarr_list; /* page array to dump VMA contents */ struct list_head pgarr_pool; /* pool of empty page arrays chain */ + void *scratch_page; /* Scratch buffer for page I/O */ + /* [multi-process checkpoint] */ struct task_struct **tasks_arr; /* array of all tasks [checkpoint] */ int nr_tasks; /* size of tasks array */ -- 1.6.2.5 _______________________________________________ Containers mailing list [email protected] https://lists.linux-foundation.org/mailman/listinfo/containers _______________________________________________ Devel mailing list [email protected] https://openvz.org/mailman/listinfo/devel
