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authorBojan Smojver <bojan@rexursive.com>2011-10-13 23:58:07 +0200
committerRafael J. Wysocki <rjw@sisk.pl>2011-10-16 23:30:38 +0200
commit081a9d043c983f161b78fdc4671324d1342b86bc (patch)
tree4382d88e5705b18a95471af2a71319401c47744f /kernel/power/swap.c
parentd231ff1af70a2df43d809173cf8c94e9c3beb853 (diff)
downloadop-kernel-dev-081a9d043c983f161b78fdc4671324d1342b86bc.zip
op-kernel-dev-081a9d043c983f161b78fdc4671324d1342b86bc.tar.gz
PM / Hibernate: Improve performance of LZO/plain hibernation, checksum image
Use threads for LZO compression/decompression on hibernate/thaw. Improve buffering on hibernate/thaw. Calculate/verify CRC32 of the image pages on hibernate/thaw. In my testing, this improved write/read speed by a factor of about two. Signed-off-by: Bojan Smojver <bojan@rexursive.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Diffstat (limited to 'kernel/power/swap.c')
-rw-r--r--kernel/power/swap.c818
1 files changed, 640 insertions, 178 deletions
diff --git a/kernel/power/swap.c b/kernel/power/swap.c
index 7c97c3a..11a594c 100644
--- a/kernel/power/swap.c
+++ b/kernel/power/swap.c
@@ -27,6 +27,10 @@
#include <linux/slab.h>
#include <linux/lzo.h>
#include <linux/vmalloc.h>
+#include <linux/cpumask.h>
+#include <linux/atomic.h>
+#include <linux/kthread.h>
+#include <linux/crc32.h>
#include "power.h"
@@ -43,8 +47,7 @@
* allocated and populated one at a time, so we only need one memory
* page to set up the entire structure.
*
- * During resume we also only need to use one swap_map_page structure
- * at a time.
+ * During resume we pick up all swap_map_page structures into a list.
*/
#define MAP_PAGE_ENTRIES (PAGE_SIZE / sizeof(sector_t) - 1)
@@ -54,6 +57,11 @@ struct swap_map_page {
sector_t next_swap;
};
+struct swap_map_page_list {
+ struct swap_map_page *map;
+ struct swap_map_page_list *next;
+};
+
/**
* The swap_map_handle structure is used for handling swap in
* a file-alike way
@@ -61,13 +69,18 @@ struct swap_map_page {
struct swap_map_handle {
struct swap_map_page *cur;
+ struct swap_map_page_list *maps;
sector_t cur_swap;
sector_t first_sector;
unsigned int k;
+ unsigned long nr_free_pages, written;
+ u32 crc32;
};
struct swsusp_header {
- char reserved[PAGE_SIZE - 20 - sizeof(sector_t) - sizeof(int)];
+ char reserved[PAGE_SIZE - 20 - sizeof(sector_t) - sizeof(int) -
+ sizeof(u32)];
+ u32 crc32;
sector_t image;
unsigned int flags; /* Flags to pass to the "boot" kernel */
char orig_sig[10];
@@ -199,6 +212,8 @@ static int mark_swapfiles(struct swap_map_handle *handle, unsigned int flags)
memcpy(swsusp_header->sig, HIBERNATE_SIG, 10);
swsusp_header->image = handle->first_sector;
swsusp_header->flags = flags;
+ if (flags & SF_CRC32_MODE)
+ swsusp_header->crc32 = handle->crc32;
error = hib_bio_write_page(swsusp_resume_block,
swsusp_header, NULL);
} else {
@@ -245,6 +260,7 @@ static int swsusp_swap_check(void)
static int write_page(void *buf, sector_t offset, struct bio **bio_chain)
{
void *src;
+ int ret;
if (!offset)
return -ENOSPC;
@@ -254,9 +270,17 @@ static int write_page(void *buf, sector_t offset, struct bio **bio_chain)
if (src) {
copy_page(src, buf);
} else {
- WARN_ON_ONCE(1);
- bio_chain = NULL; /* Go synchronous */
- src = buf;
+ ret = hib_wait_on_bio_chain(bio_chain); /* Free pages */
+ if (ret)
+ return ret;
+ src = (void *)__get_free_page(__GFP_WAIT | __GFP_HIGH);
+ if (src) {
+ copy_page(src, buf);
+ } else {
+ WARN_ON_ONCE(1);
+ bio_chain = NULL; /* Go synchronous */
+ src = buf;
+ }
}
} else {
src = buf;
@@ -293,6 +317,8 @@ static int get_swap_writer(struct swap_map_handle *handle)
goto err_rel;
}
handle->k = 0;
+ handle->nr_free_pages = nr_free_pages() >> 1;
+ handle->written = 0;
handle->first_sector = handle->cur_swap;
return 0;
err_rel:
@@ -316,20 +342,23 @@ static int swap_write_page(struct swap_map_handle *handle, void *buf,
return error;
handle->cur->entries[handle->k++] = offset;
if (handle->k >= MAP_PAGE_ENTRIES) {
- error = hib_wait_on_bio_chain(bio_chain);
- if (error)
- goto out;
offset = alloc_swapdev_block(root_swap);
if (!offset)
return -ENOSPC;
handle->cur->next_swap = offset;
- error = write_page(handle->cur, handle->cur_swap, NULL);
+ error = write_page(handle->cur, handle->cur_swap, bio_chain);
if (error)
goto out;
clear_page(handle->cur);
handle->cur_swap = offset;
handle->k = 0;
}
+ if (bio_chain && ++handle->written > handle->nr_free_pages) {
+ error = hib_wait_on_bio_chain(bio_chain);
+ if (error)
+ goto out;
+ handle->written = 0;
+ }
out:
return error;
}
@@ -372,6 +401,13 @@ static int swap_writer_finish(struct swap_map_handle *handle,
LZO_HEADER, PAGE_SIZE)
#define LZO_CMP_SIZE (LZO_CMP_PAGES * PAGE_SIZE)
+/* Maximum number of threads for compression/decompression. */
+#define LZO_THREADS 3
+
+/* Maximum number of pages for read buffering. */
+#define LZO_READ_PAGES (MAP_PAGE_ENTRIES * 8)
+
+
/**
* save_image - save the suspend image data
*/
@@ -419,6 +455,92 @@ static int save_image(struct swap_map_handle *handle,
return ret;
}
+/**
+ * Structure used for CRC32.
+ */
+struct crc_data {
+ struct task_struct *thr; /* thread */
+ atomic_t ready; /* ready to start flag */
+ atomic_t stop; /* ready to stop flag */
+ unsigned run_threads; /* nr current threads */
+ wait_queue_head_t go; /* start crc update */
+ wait_queue_head_t done; /* crc update done */
+ u32 *crc32; /* points to handle's crc32 */
+ size_t *unc_len[LZO_THREADS]; /* uncompressed lengths */
+ unsigned char *unc[LZO_THREADS]; /* uncompressed data */
+};
+
+/**
+ * CRC32 update function that runs in its own thread.
+ */
+static int crc32_threadfn(void *data)
+{
+ struct crc_data *d = data;
+ unsigned i;
+
+ while (1) {
+ wait_event(d->go, atomic_read(&d->ready) ||
+ kthread_should_stop());
+ if (kthread_should_stop()) {
+ d->thr = NULL;
+ atomic_set(&d->stop, 1);
+ wake_up(&d->done);
+ break;
+ }
+ atomic_set(&d->ready, 0);
+
+ for (i = 0; i < d->run_threads; i++)
+ *d->crc32 = crc32_le(*d->crc32,
+ d->unc[i], *d->unc_len[i]);
+ atomic_set(&d->stop, 1);
+ wake_up(&d->done);
+ }
+ return 0;
+}
+/**
+ * Structure used for LZO data compression.
+ */
+struct cmp_data {
+ struct task_struct *thr; /* thread */
+ atomic_t ready; /* ready to start flag */
+ atomic_t stop; /* ready to stop flag */
+ int ret; /* return code */
+ wait_queue_head_t go; /* start compression */
+ wait_queue_head_t done; /* compression done */
+ size_t unc_len; /* uncompressed length */
+ size_t cmp_len; /* compressed length */
+ unsigned char unc[LZO_UNC_SIZE]; /* uncompressed buffer */
+ unsigned char cmp[LZO_CMP_SIZE]; /* compressed buffer */
+ unsigned char wrk[LZO1X_1_MEM_COMPRESS]; /* compression workspace */
+};
+
+/**
+ * Compression function that runs in its own thread.
+ */
+static int lzo_compress_threadfn(void *data)
+{
+ struct cmp_data *d = data;
+
+ while (1) {
+ wait_event(d->go, atomic_read(&d->ready) ||
+ kthread_should_stop());
+ if (kthread_should_stop()) {
+ d->thr = NULL;
+ d->ret = -1;
+ atomic_set(&d->stop, 1);
+ wake_up(&d->done);
+ break;
+ }
+ atomic_set(&d->ready, 0);
+
+ d->ret = lzo1x_1_compress(d->unc, d->unc_len,
+ d->cmp + LZO_HEADER, &d->cmp_len,
+ d->wrk);
+ atomic_set(&d->stop, 1);
+ wake_up(&d->done);
+ }
+ return 0;
+}
/**
* save_image_lzo - Save the suspend image data compressed with LZO.
@@ -437,42 +559,93 @@ static int save_image_lzo(struct swap_map_handle *handle,
struct bio *bio;
struct timeval start;
struct timeval stop;
- size_t off, unc_len, cmp_len;
- unsigned char *unc, *cmp, *wrk, *page;
+ size_t off;
+ unsigned thr, run_threads, nr_threads;
+ unsigned char *page = NULL;
+ struct cmp_data *data = NULL;
+ struct crc_data *crc = NULL;
+
+ /*
+ * We'll limit the number of threads for compression to limit memory
+ * footprint.
+ */
+ nr_threads = num_online_cpus() - 1;
+ nr_threads = clamp_val(nr_threads, 1, LZO_THREADS);
page = (void *)__get_free_page(__GFP_WAIT | __GFP_HIGH);
if (!page) {
printk(KERN_ERR "PM: Failed to allocate LZO page\n");
- return -ENOMEM;
+ ret = -ENOMEM;
+ goto out_clean;
}
- wrk = vmalloc(LZO1X_1_MEM_COMPRESS);
- if (!wrk) {
- printk(KERN_ERR "PM: Failed to allocate LZO workspace\n");
- free_page((unsigned long)page);
- return -ENOMEM;
+ data = vmalloc(sizeof(*data) * nr_threads);
+ if (!data) {
+ printk(KERN_ERR "PM: Failed to allocate LZO data\n");
+ ret = -ENOMEM;
+ goto out_clean;
}
+ for (thr = 0; thr < nr_threads; thr++)
+ memset(&data[thr], 0, offsetof(struct cmp_data, go));
- unc = vmalloc(LZO_UNC_SIZE);
- if (!unc) {
- printk(KERN_ERR "PM: Failed to allocate LZO uncompressed\n");
- vfree(wrk);
- free_page((unsigned long)page);
- return -ENOMEM;
+ crc = kmalloc(sizeof(*crc), GFP_KERNEL);
+ if (!crc) {
+ printk(KERN_ERR "PM: Failed to allocate crc\n");
+ ret = -ENOMEM;
+ goto out_clean;
+ }
+ memset(crc, 0, offsetof(struct crc_data, go));
+
+ /*
+ * Start the compression threads.
+ */
+ for (thr = 0; thr < nr_threads; thr++) {
+ init_waitqueue_head(&data[thr].go);
+ init_waitqueue_head(&data[thr].done);
+
+ data[thr].thr = kthread_run(lzo_compress_threadfn,
+ &data[thr],
+ "image_compress/%u", thr);
+ if (IS_ERR(data[thr].thr)) {
+ data[thr].thr = NULL;
+ printk(KERN_ERR
+ "PM: Cannot start compression threads\n");
+ ret = -ENOMEM;
+ goto out_clean;
+ }
}
- cmp = vmalloc(LZO_CMP_SIZE);
- if (!cmp) {
- printk(KERN_ERR "PM: Failed to allocate LZO compressed\n");
- vfree(unc);
- vfree(wrk);
- free_page((unsigned long)page);
- return -ENOMEM;
+ /*
+ * Adjust number of free pages after all allocations have been done.
+ * We don't want to run out of pages when writing.
+ */
+ handle->nr_free_pages = nr_free_pages() >> 1;
+
+ /*
+ * Start the CRC32 thread.
+ */
+ init_waitqueue_head(&crc->go);
+ init_waitqueue_head(&crc->done);
+
+ handle->crc32 = 0;
+ crc->crc32 = &handle->crc32;
+ for (thr = 0; thr < nr_threads; thr++) {
+ crc->unc[thr] = data[thr].unc;
+ crc->unc_len[thr] = &data[thr].unc_len;
+ }
+
+ crc->thr = kthread_run(crc32_threadfn, crc, "image_crc32");
+ if (IS_ERR(crc->thr)) {
+ crc->thr = NULL;
+ printk(KERN_ERR "PM: Cannot start CRC32 thread\n");
+ ret = -ENOMEM;
+ goto out_clean;
}
printk(KERN_INFO
+ "PM: Using %u thread(s) for compression.\n"
"PM: Compressing and saving image data (%u pages) ... ",
- nr_to_write);
+ nr_threads, nr_to_write);
m = nr_to_write / 100;
if (!m)
m = 1;
@@ -480,55 +653,83 @@ static int save_image_lzo(struct swap_map_handle *handle,
bio = NULL;
do_gettimeofday(&start);
for (;;) {
- for (off = 0; off < LZO_UNC_SIZE; off += PAGE_SIZE) {
- ret = snapshot_read_next(snapshot);
- if (ret < 0)
- goto out_finish;
-
- if (!ret)
+ for (thr = 0; thr < nr_threads; thr++) {
+ for (off = 0; off < LZO_UNC_SIZE; off += PAGE_SIZE) {
+ ret = snapshot_read_next(snapshot);
+ if (ret < 0)
+ goto out_finish;
+
+ if (!ret)
+ break;
+
+ memcpy(data[thr].unc + off,
+ data_of(*snapshot), PAGE_SIZE);
+
+ if (!(nr_pages % m))
+ printk(KERN_CONT "\b\b\b\b%3d%%",
+ nr_pages / m);
+ nr_pages++;
+ }
+ if (!off)
break;
- memcpy(unc + off, data_of(*snapshot), PAGE_SIZE);
+ data[thr].unc_len = off;
- if (!(nr_pages % m))
- printk(KERN_CONT "\b\b\b\b%3d%%", nr_pages / m);
- nr_pages++;
+ atomic_set(&data[thr].ready, 1);
+ wake_up(&data[thr].go);
}
- if (!off)
+ if (!thr)
break;
- unc_len = off;
- ret = lzo1x_1_compress(unc, unc_len,
- cmp + LZO_HEADER, &cmp_len, wrk);
- if (ret < 0) {
- printk(KERN_ERR "PM: LZO compression failed\n");
- break;
- }
+ crc->run_threads = thr;
+ atomic_set(&crc->ready, 1);
+ wake_up(&crc->go);
- if (unlikely(!cmp_len ||
- cmp_len > lzo1x_worst_compress(unc_len))) {
- printk(KERN_ERR "PM: Invalid LZO compressed length\n");
- ret = -1;
- break;
- }
+ for (run_threads = thr, thr = 0; thr < run_threads; thr++) {
+ wait_event(data[thr].done,
+ atomic_read(&data[thr].stop));
+ atomic_set(&data[thr].stop, 0);
- *(size_t *)cmp = cmp_len;
+ ret = data[thr].ret;
- /*
- * Given we are writing one page at a time to disk, we copy
- * that much from the buffer, although the last bit will likely
- * be smaller than full page. This is OK - we saved the length
- * of the compressed data, so any garbage at the end will be
- * discarded when we read it.
- */
- for (off = 0; off < LZO_HEADER + cmp_len; off += PAGE_SIZE) {
- memcpy(page, cmp + off, PAGE_SIZE);
+ if (ret < 0) {
+ printk(KERN_ERR "PM: LZO compression failed\n");
+ goto out_finish;
+ }
- ret = swap_write_page(handle, page, &bio);
- if (ret)
+ if (unlikely(!data[thr].cmp_len ||
+ data[thr].cmp_len >
+ lzo1x_worst_compress(data[thr].unc_len))) {
+ printk(KERN_ERR
+ "PM: Invalid LZO compressed length\n");
+ ret = -1;
goto out_finish;
+ }
+
+ *(size_t *)data[thr].cmp = data[thr].cmp_len;
+
+ /*
+ * Given we are writing one page at a time to disk, we
+ * copy that much from the buffer, although the last
+ * bit will likely be smaller than full page. This is
+ * OK - we saved the length of the compressed data, so
+ * any garbage at the end will be discarded when we
+ * read it.
+ */
+ for (off = 0;
+ off < LZO_HEADER + data[thr].cmp_len;
+ off += PAGE_SIZE) {
+ memcpy(page, data[thr].cmp + off, PAGE_SIZE);
+
+ ret = swap_write_page(handle, page, &bio);
+ if (ret)
+ goto out_finish;
+ }
}
+
+ wait_event(crc->done, atomic_read(&crc->stop));
+ atomic_set(&crc->stop, 0);
}
out_finish:
@@ -536,16 +737,25 @@ out_finish:
do_gettimeofday(&stop);
if (!ret)
ret = err2;
- if (!ret)
+ if (!ret) {
printk(KERN_CONT "\b\b\b\bdone\n");
- else
+ } else {
printk(KERN_CONT "\n");
+ }
swsusp_show_speed(&start, &stop, nr_to_write, "Wrote");
-
- vfree(cmp);
- vfree(unc);
- vfree(wrk);
- free_page((unsigned long)page);
+out_clean:
+ if (crc) {
+ if (crc->thr)
+ kthread_stop(crc->thr);
+ kfree(crc);
+ }
+ if (data) {
+ for (thr = 0; thr < nr_threads; thr++)
+ if (data[thr].thr)
+ kthread_stop(data[thr].thr);
+ vfree(data);
+ }
+ if (page) free_page((unsigned long)page);
return ret;
}
@@ -625,8 +835,15 @@ out_finish:
static void release_swap_reader(struct swap_map_handle *handle)
{
- if (handle->cur)
- free_page((unsigned long)handle->cur);
+ struct swap_map_page_list *tmp;
+
+ while (handle->maps) {
+ if (handle->maps->map)
+ free_page((unsigned long)handle->maps->map);
+ tmp = handle->maps;
+ handle->maps = handle->maps->next;
+ kfree(tmp);
+ }
handle->cur = NULL;
}
@@ -634,22 +851,46 @@ static int get_swap_reader(struct swap_map_handle *handle,
unsigned int *flags_p)
{
int error;
+ struct swap_map_page_list *tmp, *last;
+ sector_t offset;
*flags_p = swsusp_header->flags;
if (!swsusp_header->image) /* how can this happen? */
return -EINVAL;
- handle->cur = (struct swap_map_page *)get_zeroed_page(__GFP_WAIT | __GFP_HIGH);
- if (!handle->cur)
- return -ENOMEM;
+ handle->cur = NULL;
+ last = handle->maps = NULL;
+ offset = swsusp_header->image;
+ while (offset) {
+ tmp = kmalloc(sizeof(*handle->maps), GFP_KERNEL);
+ if (!tmp) {
+ release_swap_reader(handle);
+ return -ENOMEM;
+ }
+ memset(tmp, 0, sizeof(*tmp));
+ if (!handle->maps)
+ handle->maps = tmp;
+ if (last)
+ last->next = tmp;
+ last = tmp;
+
+ tmp->map = (struct swap_map_page *)
+ __get_free_page(__GFP_WAIT | __GFP_HIGH);
+ if (!tmp->map) {
+ release_swap_reader(handle);
+ return -ENOMEM;
+ }
- error = hib_bio_read_page(swsusp_header->image, handle->cur, NULL);
- if (error) {
- release_swap_reader(handle);
- return error;
+ error = hib_bio_read_page(offset, tmp->map, NULL);
+ if (error) {
+ release_swap_reader(handle);
+ return error;
+ }
+ offset = tmp->map->next_swap;
}
handle->k = 0;
+ handle->cur = handle->maps->map;
return 0;
}
@@ -658,6 +899,7 @@ static int swap_read_page(struct swap_map_handle *handle, void *buf,
{
sector_t offset;
int error;
+ struct swap_map_page_list *tmp;
if (!handle->cur)
return -EINVAL;
@@ -668,13 +910,15 @@ static int swap_read_page(struct swap_map_handle *handle, void *buf,
if (error)
return error;
if (++handle->k >= MAP_PAGE_ENTRIES) {
- error = hib_wait_on_bio_chain(bio_chain);
handle->k = 0;
- offset = handle->cur->next_swap;
- if (!offset)
+ free_page((unsigned long)handle->maps->map);
+ tmp = handle->maps;
+ handle->maps = handle->maps->next;
+ kfree(tmp);
+ if (!handle->maps)
release_swap_reader(handle);
- else if (!error)
- error = hib_bio_read_page(offset, handle->cur, NULL);
+ else
+ handle->cur = handle->maps->map;
}
return error;
}
@@ -697,7 +941,7 @@ static int load_image(struct swap_map_handle *handle,
unsigned int nr_to_read)
{
unsigned int m;
- int error = 0;
+ int ret = 0;
struct timeval start;
struct timeval stop;
struct bio *bio;
@@ -713,15 +957,15 @@ static int load_image(struct swap_map_handle *handle,
bio = NULL;
do_gettimeofday(&start);
for ( ; ; ) {
- error = snapshot_write_next(snapshot);
- if (error <= 0)
+ ret = snapshot_write_next(snapshot);
+ if (ret <= 0)
break;
- error = swap_read_page(handle, data_of(*snapshot), &bio);
- if (error)
+ ret = swap_read_page(handle, data_of(*snapshot), &bio);
+ if (ret)
break;
if (snapshot->sync_read)
- error = hib_wait_on_bio_chain(&bio);
- if (error)
+ ret = hib_wait_on_bio_chain(&bio);
+ if (ret)
break;
if (!(nr_pages % m))
printk("\b\b\b\b%3d%%", nr_pages / m);
@@ -729,17 +973,61 @@ static int load_image(struct swap_map_handle *handle,
}
err2 = hib_wait_on_bio_chain(&bio);
do_gettimeofday(&stop);
- if (!error)
- error = err2;
- if (!error) {
+ if (!ret)
+ ret = err2;
+ if (!ret) {
printk("\b\b\b\bdone\n");
snapshot_write_finalize(snapshot);
if (!snapshot_image_loaded(snapshot))
- error = -ENODATA;
+ ret = -ENODATA;
} else
printk("\n");
swsusp_show_speed(&start, &stop, nr_to_read, "Read");
- return error;
+ return ret;
+}
+
+/**
+ * Structure used for LZO data decompression.
+ */
+struct dec_data {
+ struct task_struct *thr; /* thread */
+ atomic_t ready; /* ready to start flag */
+ atomic_t stop; /* ready to stop flag */
+ int ret; /* return code */
+ wait_queue_head_t go; /* start decompression */
+ wait_queue_head_t done; /* decompression done */
+ size_t unc_len; /* uncompressed length */
+ size_t cmp_len; /* compressed length */
+ unsigned char unc[LZO_UNC_SIZE]; /* uncompressed buffer */
+ unsigned char cmp[LZO_CMP_SIZE]; /* compressed buffer */
+};
+
+/**
+ * Deompression function that runs in its own thread.
+ */
+static int lzo_decompress_threadfn(void *data)
+{
+ struct dec_data *d = data;
+
+ while (1) {
+ wait_event(d->go, atomic_read(&d->ready) ||
+ kthread_should_stop());
+ if (kthread_should_stop()) {
+ d->thr = NULL;
+ d->ret = -1;
+ atomic_set(&d->stop, 1);
+ wake_up(&d->done);
+ break;
+ }
+ atomic_set(&d->ready, 0);
+
+ d->unc_len = LZO_UNC_SIZE;
+ d->ret = lzo1x_decompress_safe(d->cmp + LZO_HEADER, d->cmp_len,
+ d->unc, &d->unc_len);
+ atomic_set(&d->stop, 1);
+ wake_up(&d->done);
+ }
+ return 0;
}
/**
@@ -753,50 +1041,120 @@ static int load_image_lzo(struct swap_map_handle *handle,
unsigned int nr_to_read)
{
unsigned int m;
- int error = 0;
+ int ret = 0;
+ int eof = 0;
struct bio *bio;
struct timeval start;
struct timeval stop;
unsigned nr_pages;
- size_t i, off, unc_len, cmp_len;
- unsigned char *unc, *cmp, *page[LZO_CMP_PAGES];
-
- for (i = 0; i < LZO_CMP_PAGES; i++) {
- page[i] = (void *)__get_free_page(__GFP_WAIT | __GFP_HIGH);
- if (!page[i]) {
- printk(KERN_ERR "PM: Failed to allocate LZO page\n");
+ size_t off;
+ unsigned i, thr, run_threads, nr_threads;
+ unsigned ring = 0, pg = 0, ring_size = 0,
+ have = 0, want, need, asked = 0;
+ unsigned long read_pages;
+ unsigned char **page = NULL;
+ struct dec_data *data = NULL;
+ struct crc_data *crc = NULL;
+
+ /*
+ * We'll limit the number of threads for decompression to limit memory
+ * footprint.
+ */
+ nr_threads = num_online_cpus() - 1;
+ nr_threads = clamp_val(nr_threads, 1, LZO_THREADS);
+
+ page = vmalloc(sizeof(*page) * LZO_READ_PAGES);
+ if (!page) {
+ printk(KERN_ERR "PM: Failed to allocate LZO page\n");
+ ret = -ENOMEM;
+ goto out_clean;
+ }
- while (i)
- free_page((unsigned long)page[--i]);
+ data = vmalloc(sizeof(*data) * nr_threads);
+ if (!data) {
+ printk(KERN_ERR "PM: Failed to allocate LZO data\n");
+ ret = -ENOMEM;
+ goto out_clean;
+ }
+ for (thr = 0; thr < nr_threads; thr++)
+ memset(&data[thr], 0, offsetof(struct dec_data, go));
- return -ENOMEM;
+ crc = kmalloc(sizeof(*crc), GFP_KERNEL);
+ if (!crc) {
+ printk(KERN_ERR "PM: Failed to allocate crc\n");
+ ret = -ENOMEM;
+ goto out_clean;
+ }
+ memset(crc, 0, offsetof(struct crc_data, go));
+
+ /*
+ * Start the decompression threads.
+ */
+ for (thr = 0; thr < nr_threads; thr++) {
+ init_waitqueue_head(&data[thr].go);
+ init_waitqueue_head(&data[thr].done);
+
+ data[thr].thr = kthread_run(lzo_decompress_threadfn,
+ &data[thr],
+ "image_decompress/%u", thr);
+ if (IS_ERR(data[thr].thr)) {
+ data[thr].thr = NULL;
+ printk(KERN_ERR
+ "PM: Cannot start decompression threads\n");
+ ret = -ENOMEM;
+ goto out_clean;
}
}
- unc = vmalloc(LZO_UNC_SIZE);
- if (!unc) {
- printk(KERN_ERR "PM: Failed to allocate LZO uncompressed\n");
-
- for (i = 0; i < LZO_CMP_PAGES; i++)
- free_page((unsigned long)page[i]);
-
- return -ENOMEM;
+ /*
+ * Start the CRC32 thread.
+ */
+ init_waitqueue_head(&crc->go);
+ init_waitqueue_head(&crc->done);
+
+ handle->crc32 = 0;
+ crc->crc32 = &handle->crc32;
+ for (thr = 0; thr < nr_threads; thr++) {
+ crc->unc[thr] = data[thr].unc;
+ crc->unc_len[thr] = &data[thr].unc_len;
}
- cmp = vmalloc(LZO_CMP_SIZE);
- if (!cmp) {
- printk(KERN_ERR "PM: Failed to allocate LZO compressed\n");
+ crc->thr = kthread_run(crc32_threadfn, crc, "image_crc32");
+ if (IS_ERR(crc->thr)) {
+ crc->thr = NULL;
+ printk(KERN_ERR "PM: Cannot start CRC32 thread\n");
+ ret = -ENOMEM;
+ goto out_clean;
+ }
- vfree(unc);
- for (i = 0; i < LZO_CMP_PAGES; i++)
- free_page((unsigned long)page[i]);
+ /*
+ * Adjust number of pages for read buffering, in case we are short.
+ */
+ read_pages = (nr_free_pages() - snapshot_get_image_size()) >> 1;
+ read_pages = clamp_val(read_pages, LZO_CMP_PAGES, LZO_READ_PAGES);
- return -ENOMEM;
+ for (i = 0; i < read_pages; i++) {
+ page[i] = (void *)__get_free_page(i < LZO_CMP_PAGES ?
+ __GFP_WAIT | __GFP_HIGH :
+ __GFP_WAIT);
+ if (!page[i]) {
+ if (i < LZO_CMP_PAGES) {
+ ring_size = i;
+ printk(KERN_ERR
+ "PM: Failed to allocate LZO pages\n");
+ ret = -ENOMEM;
+ goto out_clean;
+ } else {
+ break;
+ }
+ }
}
+ want = ring_size = i;
printk(KERN_INFO
+ "PM: Using %u thread(s) for decompression.\n"
"PM: Loading and decompressing image data (%u pages) ... ",
- nr_to_read);
+ nr_threads, nr_to_read);
m = nr_to_read / 100;
if (!m)
m = 1;
@@ -804,85 +1162,189 @@ static int load_image_lzo(struct swap_map_handle *handle,
bio = NULL;
do_gettimeofday(&start);
- error = snapshot_write_next(snapshot);
- if (error <= 0)
+ ret = snapshot_write_next(snapshot);
+ if (ret <= 0)
goto out_finish;
- for (;;) {
- error = swap_read_page(handle, page[0], NULL); /* sync */
- if (error)
- break;
-
- cmp_len = *(size_t *)page[0];
- if (unlikely(!cmp_len ||
- cmp_len > lzo1x_worst_compress(LZO_UNC_SIZE))) {
- printk(KERN_ERR "PM: Invalid LZO compressed length\n");
- error = -1;
- break;
+ for(;;) {
+ for (i = 0; !eof && i < want; i++) {
+ ret = swap_read_page(handle, page[ring], &bio);
+ if (ret) {
+ /*
+ * On real read error, finish. On end of data,
+ * set EOF flag and just exit the read loop.
+ */
+ if (handle->cur &&
+ handle->cur->entries[handle->k]) {
+ goto out_finish;
+ } else {
+ eof = 1;
+ break;
+ }
+ }
+ if (++ring >= ring_size)
+ ring = 0;
}
+ asked += i;
+ want -= i;
- for (off = PAGE_SIZE, i = 1;
- off < LZO_HEADER + cmp_len; off += PAGE_SIZE, i++) {
- error = swap_read_page(handle, page[i], &bio);
- if (error)
+ /*
+ * We are out of data, wait for some more.
+ */
+ if (!have) {
+ if (!asked)
+ break;
+
+ ret = hib_wait_on_bio_chain(&bio);
+ if (ret)
goto out_finish;
+ have += asked;
+ asked = 0;
+ if (eof)
+ eof = 2;
}
- error = hib_wait_on_bio_chain(&bio); /* need all data now */
- if (error)
- goto out_finish;
-
- for (off = 0, i = 0;
- off < LZO_HEADER + cmp_len; off += PAGE_SIZE, i++) {
- memcpy(cmp + off, page[i], PAGE_SIZE);
+ if (crc->run_threads) {
+ wait_event(crc->done, atomic_read(&crc->stop));
+ atomic_set(&crc->stop, 0);
+ crc->run_threads = 0;
}
- unc_len = LZO_UNC_SIZE;
- error = lzo1x_decompress_safe(cmp + LZO_HEADER, cmp_len,
- unc, &unc_len);
- if (error < 0) {
- printk(KERN_ERR "PM: LZO decompression failed\n");
- break;
+ for (thr = 0; have && thr < nr_threads; thr++) {
+ data[thr].cmp_len = *(size_t *)page[pg];
+ if (unlikely(!data[thr].cmp_len ||
+ data[thr].cmp_len >
+ lzo1x_worst_compress(LZO_UNC_SIZE))) {
+ printk(KERN_ERR
+ "PM: Invalid LZO compressed length\n");
+ ret = -1;
+ goto out_finish;
+ }
+
+ need = DIV_ROUND_UP(data[thr].cmp_len + LZO_HEADER,
+ PAGE_SIZE);
+ if (need > have) {
+ if (eof > 1) {
+ ret = -1;
+ goto out_finish;
+ }
+ break;
+ }
+
+ for (off = 0;
+ off < LZO_HEADER + data[thr].cmp_len;
+ off += PAGE_SIZE) {
+ memcpy(data[thr].cmp + off,
+ page[pg], PAGE_SIZE);
+ have--;
+ want++;
+ if (++pg >= ring_size)
+ pg = 0;
+ }
+
+ atomic_set(&data[thr].ready, 1);
+ wake_up(&data[thr].go);
}
- if (unlikely(!unc_len ||
- unc_len > LZO_UNC_SIZE ||
- unc_len & (PAGE_SIZE - 1))) {
- printk(KERN_ERR "PM: Invalid LZO uncompressed length\n");
- error = -1;
- break;
+ /*
+ * Wait for more data while we are decompressing.
+ */
+ if (have < LZO_CMP_PAGES && asked) {
+ ret = hib_wait_on_bio_chain(&bio);
+ if (ret)
+ goto out_finish;
+ have += asked;
+ asked = 0;
+ if (eof)
+ eof = 2;
}
- for (off = 0; off < unc_len; off += PAGE_SIZE) {
- memcpy(data_of(*snapshot), unc + off, PAGE_SIZE);
+ for (run_threads = thr, thr = 0; thr < run_threads; thr++) {
+ wait_event(data[thr].done,
+ atomic_read(&data[thr].stop));
+ atomic_set(&data[thr].stop, 0);
+
+ ret = data[thr].ret;
- if (!(nr_pages % m))
- printk("\b\b\b\b%3d%%", nr_pages / m);
- nr_pages++;
+ if (ret < 0) {
+ printk(KERN_ERR
+ "PM: LZO decompression failed\n");
+ goto out_finish;
+ }
- error = snapshot_write_next(snapshot);
- if (error <= 0)
+ if (unlikely(!data[thr].unc_len ||
+ data[thr].unc_len > LZO_UNC_SIZE ||
+ data[thr].unc_len & (PAGE_SIZE - 1))) {
+ printk(KERN_ERR
+ "PM: Invalid LZO uncompressed length\n");
+ ret = -1;
goto out_finish;
+ }
+
+ for (off = 0;
+ off < data[thr].unc_len; off += PAGE_SIZE) {
+ memcpy(data_of(*snapshot),
+ data[thr].unc + off, PAGE_SIZE);
+
+ if (!(nr_pages % m))
+ printk("\b\b\b\b%3d%%", nr_pages / m);
+ nr_pages++;
+
+ ret = snapshot_write_next(snapshot);
+ if (ret <= 0) {
+ crc->run_threads = thr + 1;
+ atomic_set(&crc->ready, 1);
+ wake_up(&crc->go);
+ goto out_finish;
+ }
+ }
}
+
+ crc->run_threads = thr;
+ atomic_set(&crc->ready, 1);
+ wake_up(&crc->go);
}
out_finish:
+ if (crc->run_threads) {
+ wait_event(crc->done, atomic_read(&crc->stop));
+ atomic_set(&crc->stop, 0);
+ }
do_gettimeofday(&stop);
- if (!error) {
+ if (!ret) {
printk("\b\b\b\bdone\n");
snapshot_write_finalize(snapshot);
if (!snapshot_image_loaded(snapshot))
- error = -ENODATA;
+ ret = -ENODATA;
+ if (!ret) {
+ if (swsusp_header->flags & SF_CRC32_MODE) {
+ if(handle->crc32 != swsusp_header->crc32) {
+ printk(KERN_ERR
+ "PM: Invalid image CRC32!\n");
+ ret = -ENODATA;
+ }
+ }
+ }
} else
printk("\n");
swsusp_show_speed(&start, &stop, nr_to_read, "Read");
-
- vfree(cmp);
- vfree(unc);
- for (i = 0; i < LZO_CMP_PAGES; i++)
+out_clean:
+ for (i = 0; i < ring_size; i++)
free_page((unsigned long)page[i]);
+ if (crc) {
+ if (crc->thr)
+ kthread_stop(crc->thr);
+ kfree(crc);
+ }
+ if (data) {
+ for (thr = 0; thr < nr_threads; thr++)
+ if (data[thr].thr)
+ kthread_stop(data[thr].thr);
+ vfree(data);
+ }
+ if (page) vfree(page);
- return error;
+ return ret;
}
/**
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