diff options
Diffstat (limited to 'kernel')
-rw-r--r-- | kernel/power/qos.c | 9 | ||||
-rw-r--r-- | kernel/power/snapshot.c | 187 |
2 files changed, 156 insertions, 40 deletions
diff --git a/kernel/power/qos.c b/kernel/power/qos.c index 782d3b41c1f3..4244b069442e 100644 --- a/kernel/power/qos.c +++ b/kernel/power/qos.c @@ -220,6 +220,11 @@ static struct pm_qos_constraints cpu_latency_constraints = { .type = PM_QOS_MIN, }; +static inline bool cpu_latency_qos_value_invalid(s32 value) +{ + return value < 0 && value != PM_QOS_DEFAULT_VALUE; +} + /** * cpu_latency_qos_limit - Return current system-wide CPU latency QoS limit. */ @@ -263,7 +268,7 @@ static void cpu_latency_qos_apply(struct pm_qos_request *req, */ void cpu_latency_qos_add_request(struct pm_qos_request *req, s32 value) { - if (!req) + if (!req || cpu_latency_qos_value_invalid(value)) return; if (cpu_latency_qos_request_active(req)) { @@ -289,7 +294,7 @@ EXPORT_SYMBOL_GPL(cpu_latency_qos_add_request); */ void cpu_latency_qos_update_request(struct pm_qos_request *req, s32 new_value) { - if (!req) + if (!req || cpu_latency_qos_value_invalid(new_value)) return; if (!cpu_latency_qos_request_active(req)) { diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c index 0415d5ecb977..87e9f7e2bdc0 100644 --- a/kernel/power/snapshot.c +++ b/kernel/power/snapshot.c @@ -404,6 +404,7 @@ struct bm_position { struct mem_zone_bm_rtree *zone; struct rtree_node *node; unsigned long node_pfn; + unsigned long cur_pfn; int node_bit; }; @@ -589,6 +590,7 @@ static void memory_bm_position_reset(struct memory_bitmap *bm) bm->cur.node = list_entry(bm->cur.zone->leaves.next, struct rtree_node, list); bm->cur.node_pfn = 0; + bm->cur.cur_pfn = BM_END_OF_MAP; bm->cur.node_bit = 0; } @@ -799,6 +801,7 @@ node_found: bm->cur.zone = zone; bm->cur.node = node; bm->cur.node_pfn = (pfn - zone->start_pfn) & ~BM_BLOCK_MASK; + bm->cur.cur_pfn = pfn; /* Set return values */ *addr = node->data; @@ -850,6 +853,11 @@ static void memory_bm_clear_current(struct memory_bitmap *bm) clear_bit(bit, bm->cur.node->data); } +static unsigned long memory_bm_get_current(struct memory_bitmap *bm) +{ + return bm->cur.cur_pfn; +} + static int memory_bm_test_bit(struct memory_bitmap *bm, unsigned long pfn) { void *addr; @@ -929,10 +937,12 @@ static unsigned long memory_bm_next_pfn(struct memory_bitmap *bm) if (bit < bits) { pfn = bm->cur.zone->start_pfn + bm->cur.node_pfn + bit; bm->cur.node_bit = bit + 1; + bm->cur.cur_pfn = pfn; return pfn; } } while (rtree_next_node(bm)); + bm->cur.cur_pfn = BM_END_OF_MAP; return BM_END_OF_MAP; } @@ -1423,14 +1433,19 @@ static unsigned int count_data_pages(void) /* * This is needed, because copy_page and memcpy are not usable for copying - * task structs. + * task structs. Returns true if the page was filled with only zeros, + * otherwise false. */ -static inline void do_copy_page(long *dst, long *src) +static inline bool do_copy_page(long *dst, long *src) { + long z = 0; int n; - for (n = PAGE_SIZE / sizeof(long); n; n--) + for (n = PAGE_SIZE / sizeof(long); n; n--) { + z |= *src; *dst++ = *src++; + } + return !z; } /** @@ -1439,17 +1454,21 @@ static inline void do_copy_page(long *dst, long *src) * Check if the page we are going to copy is marked as present in the kernel * page tables. This always is the case if CONFIG_DEBUG_PAGEALLOC or * CONFIG_ARCH_HAS_SET_DIRECT_MAP is not set. In that case kernel_page_present() - * always returns 'true'. + * always returns 'true'. Returns true if the page was entirely composed of + * zeros, otherwise it will return false. */ -static void safe_copy_page(void *dst, struct page *s_page) +static bool safe_copy_page(void *dst, struct page *s_page) { + bool zeros_only; + if (kernel_page_present(s_page)) { - do_copy_page(dst, page_address(s_page)); + zeros_only = do_copy_page(dst, page_address(s_page)); } else { hibernate_map_page(s_page); - do_copy_page(dst, page_address(s_page)); + zeros_only = do_copy_page(dst, page_address(s_page)); hibernate_unmap_page(s_page); } + return zeros_only; } #ifdef CONFIG_HIGHMEM @@ -1459,17 +1478,18 @@ static inline struct page *page_is_saveable(struct zone *zone, unsigned long pfn saveable_highmem_page(zone, pfn) : saveable_page(zone, pfn); } -static void copy_data_page(unsigned long dst_pfn, unsigned long src_pfn) +static bool copy_data_page(unsigned long dst_pfn, unsigned long src_pfn) { struct page *s_page, *d_page; void *src, *dst; + bool zeros_only; s_page = pfn_to_page(src_pfn); d_page = pfn_to_page(dst_pfn); if (PageHighMem(s_page)) { src = kmap_atomic(s_page); dst = kmap_atomic(d_page); - do_copy_page(dst, src); + zeros_only = do_copy_page(dst, src); kunmap_atomic(dst); kunmap_atomic(src); } else { @@ -1478,30 +1498,39 @@ static void copy_data_page(unsigned long dst_pfn, unsigned long src_pfn) * The page pointed to by src may contain some kernel * data modified by kmap_atomic() */ - safe_copy_page(buffer, s_page); + zeros_only = safe_copy_page(buffer, s_page); dst = kmap_atomic(d_page); copy_page(dst, buffer); kunmap_atomic(dst); } else { - safe_copy_page(page_address(d_page), s_page); + zeros_only = safe_copy_page(page_address(d_page), s_page); } } + return zeros_only; } #else #define page_is_saveable(zone, pfn) saveable_page(zone, pfn) -static inline void copy_data_page(unsigned long dst_pfn, unsigned long src_pfn) +static inline int copy_data_page(unsigned long dst_pfn, unsigned long src_pfn) { - safe_copy_page(page_address(pfn_to_page(dst_pfn)), + return safe_copy_page(page_address(pfn_to_page(dst_pfn)), pfn_to_page(src_pfn)); } #endif /* CONFIG_HIGHMEM */ -static void copy_data_pages(struct memory_bitmap *copy_bm, - struct memory_bitmap *orig_bm) +/* + * Copy data pages will copy all pages into pages pulled from the copy_bm. + * If a page was entirely filled with zeros it will be marked in the zero_bm. + * + * Returns the number of pages copied. + */ +static unsigned long copy_data_pages(struct memory_bitmap *copy_bm, + struct memory_bitmap *orig_bm, + struct memory_bitmap *zero_bm) { + unsigned long copied_pages = 0; struct zone *zone; - unsigned long pfn; + unsigned long pfn, copy_pfn; for_each_populated_zone(zone) { unsigned long max_zone_pfn; @@ -1514,18 +1543,29 @@ static void copy_data_pages(struct memory_bitmap *copy_bm, } memory_bm_position_reset(orig_bm); memory_bm_position_reset(copy_bm); + copy_pfn = memory_bm_next_pfn(copy_bm); for(;;) { pfn = memory_bm_next_pfn(orig_bm); if (unlikely(pfn == BM_END_OF_MAP)) break; - copy_data_page(memory_bm_next_pfn(copy_bm), pfn); + if (copy_data_page(copy_pfn, pfn)) { + memory_bm_set_bit(zero_bm, pfn); + /* Use this copy_pfn for a page that is not full of zeros */ + continue; + } + copied_pages++; + copy_pfn = memory_bm_next_pfn(copy_bm); } + return copied_pages; } /* Total number of image pages */ static unsigned int nr_copy_pages; /* Number of pages needed for saving the original pfns of the image pages */ static unsigned int nr_meta_pages; +/* Number of zero pages */ +static unsigned int nr_zero_pages; + /* * Numbers of normal and highmem page frames allocated for hibernation image * before suspending devices. @@ -1546,6 +1586,9 @@ static struct memory_bitmap orig_bm; */ static struct memory_bitmap copy_bm; +/* Memory bitmap which tracks which saveable pages were zero filled. */ +static struct memory_bitmap zero_bm; + /** * swsusp_free - Free pages allocated for hibernation image. * @@ -1590,6 +1633,7 @@ loop: out: nr_copy_pages = 0; nr_meta_pages = 0; + nr_zero_pages = 0; restore_pblist = NULL; buffer = NULL; alloc_normal = 0; @@ -1808,8 +1852,15 @@ int hibernate_preallocate_memory(void) goto err_out; } + error = memory_bm_create(&zero_bm, GFP_IMAGE, PG_ANY); + if (error) { + pr_err("Cannot allocate zero bitmap\n"); + goto err_out; + } + alloc_normal = 0; alloc_highmem = 0; + nr_zero_pages = 0; /* Count the number of saveable data pages. */ save_highmem = count_highmem_pages(); @@ -2089,19 +2140,19 @@ asmlinkage __visible int swsusp_save(void) * Kill them. */ drain_local_pages(NULL); - copy_data_pages(©_bm, &orig_bm); + nr_copy_pages = copy_data_pages(©_bm, &orig_bm, &zero_bm); /* * End of critical section. From now on, we can write to memory, * but we should not touch disk. This specially means we must _not_ * touch swap space! Except we must write out our image of course. */ - nr_pages += nr_highmem; - nr_copy_pages = nr_pages; + /* We don't actually copy the zero pages */ + nr_zero_pages = nr_pages - nr_copy_pages; nr_meta_pages = DIV_ROUND_UP(nr_pages * sizeof(long), PAGE_SIZE); - pr_info("Image created (%d pages copied)\n", nr_pages); + pr_info("Image created (%d pages copied, %d zero pages)\n", nr_copy_pages, nr_zero_pages); return 0; } @@ -2146,15 +2197,22 @@ static int init_header(struct swsusp_info *info) return init_header_complete(info); } +#define ENCODED_PFN_ZERO_FLAG ((unsigned long)1 << (BITS_PER_LONG - 1)) +#define ENCODED_PFN_MASK (~ENCODED_PFN_ZERO_FLAG) + /** * pack_pfns - Prepare PFNs for saving. * @bm: Memory bitmap. * @buf: Memory buffer to store the PFNs in. + * @zero_bm: Memory bitmap containing PFNs of zero pages. * * PFNs corresponding to set bits in @bm are stored in the area of memory - * pointed to by @buf (1 page at a time). + * pointed to by @buf (1 page at a time). Pages which were filled with only + * zeros will have the highest bit set in the packed format to distinguish + * them from PFNs which will be contained in the image file. */ -static inline void pack_pfns(unsigned long *buf, struct memory_bitmap *bm) +static inline void pack_pfns(unsigned long *buf, struct memory_bitmap *bm, + struct memory_bitmap *zero_bm) { int j; @@ -2162,6 +2220,8 @@ static inline void pack_pfns(unsigned long *buf, struct memory_bitmap *bm) buf[j] = memory_bm_next_pfn(bm); if (unlikely(buf[j] == BM_END_OF_MAP)) break; + if (memory_bm_test_bit(zero_bm, buf[j])) + buf[j] |= ENCODED_PFN_ZERO_FLAG; } } @@ -2203,7 +2263,7 @@ int snapshot_read_next(struct snapshot_handle *handle) memory_bm_position_reset(©_bm); } else if (handle->cur <= nr_meta_pages) { clear_page(buffer); - pack_pfns(buffer, &orig_bm); + pack_pfns(buffer, &orig_bm, &zero_bm); } else { struct page *page; @@ -2299,24 +2359,35 @@ static int load_header(struct swsusp_info *info) * unpack_orig_pfns - Set bits corresponding to given PFNs in a memory bitmap. * @bm: Memory bitmap. * @buf: Area of memory containing the PFNs. + * @zero_bm: Memory bitmap with the zero PFNs marked. * * For each element of the array pointed to by @buf (1 page at a time), set the - * corresponding bit in @bm. + * corresponding bit in @bm. If the page was originally populated with only + * zeros then a corresponding bit will also be set in @zero_bm. */ -static int unpack_orig_pfns(unsigned long *buf, struct memory_bitmap *bm) +static int unpack_orig_pfns(unsigned long *buf, struct memory_bitmap *bm, + struct memory_bitmap *zero_bm) { + unsigned long decoded_pfn; + bool zero; int j; for (j = 0; j < PAGE_SIZE / sizeof(long); j++) { if (unlikely(buf[j] == BM_END_OF_MAP)) break; - if (pfn_valid(buf[j]) && memory_bm_pfn_present(bm, buf[j])) { - memory_bm_set_bit(bm, buf[j]); + zero = !!(buf[j] & ENCODED_PFN_ZERO_FLAG); + decoded_pfn = buf[j] & ENCODED_PFN_MASK; + if (pfn_valid(decoded_pfn) && memory_bm_pfn_present(bm, decoded_pfn)) { + memory_bm_set_bit(bm, decoded_pfn); + if (zero) { + memory_bm_set_bit(zero_bm, decoded_pfn); + nr_zero_pages++; + } } else { - if (!pfn_valid(buf[j])) + if (!pfn_valid(decoded_pfn)) pr_err(FW_BUG "Memory map mismatch at 0x%llx after hibernation\n", - (unsigned long long)PFN_PHYS(buf[j])); + (unsigned long long)PFN_PHYS(decoded_pfn)); return -EFAULT; } } @@ -2538,6 +2609,7 @@ static inline void free_highmem_data(void) {} * prepare_image - Make room for loading hibernation image. * @new_bm: Uninitialized memory bitmap structure. * @bm: Memory bitmap with unsafe pages marked. + * @zero_bm: Memory bitmap containing the zero pages. * * Use @bm to mark the pages that will be overwritten in the process of * restoring the system memory state from the suspend image ("unsafe" pages) @@ -2548,10 +2620,15 @@ static inline void free_highmem_data(void) {} * pages will be used for just yet. Instead, we mark them all as allocated and * create a lists of "safe" pages to be used later. On systems with high * memory a list of "safe" highmem pages is created too. + * + * Because it was not known which pages were unsafe when @zero_bm was created, + * make a copy of it and recreate it within safe pages. */ -static int prepare_image(struct memory_bitmap *new_bm, struct memory_bitmap *bm) +static int prepare_image(struct memory_bitmap *new_bm, struct memory_bitmap *bm, + struct memory_bitmap *zero_bm) { unsigned int nr_pages, nr_highmem; + struct memory_bitmap tmp; struct linked_page *lp; int error; @@ -2568,6 +2645,24 @@ static int prepare_image(struct memory_bitmap *new_bm, struct memory_bitmap *bm) duplicate_memory_bitmap(new_bm, bm); memory_bm_free(bm, PG_UNSAFE_KEEP); + + /* Make a copy of zero_bm so it can be created in safe pages */ + error = memory_bm_create(&tmp, GFP_ATOMIC, PG_ANY); + if (error) + goto Free; + + duplicate_memory_bitmap(&tmp, zero_bm); + memory_bm_free(zero_bm, PG_UNSAFE_KEEP); + + /* Recreate zero_bm in safe pages */ + error = memory_bm_create(zero_bm, GFP_ATOMIC, PG_SAFE); + if (error) + goto Free; + + duplicate_memory_bitmap(zero_bm, &tmp); + memory_bm_free(&tmp, PG_UNSAFE_KEEP); + /* At this point zero_bm is in safe pages and it can be used for restoring. */ + if (nr_highmem > 0) { error = prepare_highmem_image(bm, &nr_highmem); if (error) @@ -2582,7 +2677,7 @@ static int prepare_image(struct memory_bitmap *new_bm, struct memory_bitmap *bm) * * nr_copy_pages cannot be less than allocated_unsafe_pages too. */ - nr_pages = nr_copy_pages - nr_highmem - allocated_unsafe_pages; + nr_pages = (nr_zero_pages + nr_copy_pages) - nr_highmem - allocated_unsafe_pages; nr_pages = DIV_ROUND_UP(nr_pages, PBES_PER_LINKED_PAGE); while (nr_pages > 0) { lp = get_image_page(GFP_ATOMIC, PG_SAFE); @@ -2595,7 +2690,7 @@ static int prepare_image(struct memory_bitmap *new_bm, struct memory_bitmap *bm) nr_pages--; } /* Preallocate memory for the image */ - nr_pages = nr_copy_pages - nr_highmem - allocated_unsafe_pages; + nr_pages = (nr_zero_pages + nr_copy_pages) - nr_highmem - allocated_unsafe_pages; while (nr_pages > 0) { lp = (struct linked_page *)get_zeroed_page(GFP_ATOMIC); if (!lp) { @@ -2683,8 +2778,9 @@ int snapshot_write_next(struct snapshot_handle *handle) static struct chain_allocator ca; int error = 0; +next: /* Check if we have already loaded the entire image */ - if (handle->cur > 1 && handle->cur > nr_meta_pages + nr_copy_pages) + if (handle->cur > 1 && handle->cur > nr_meta_pages + nr_copy_pages + nr_zero_pages) return 0; handle->sync_read = 1; @@ -2709,19 +2805,26 @@ int snapshot_write_next(struct snapshot_handle *handle) if (error) return error; + error = memory_bm_create(&zero_bm, GFP_ATOMIC, PG_ANY); + if (error) + return error; + + nr_zero_pages = 0; + hibernate_restore_protection_begin(); } else if (handle->cur <= nr_meta_pages + 1) { - error = unpack_orig_pfns(buffer, ©_bm); + error = unpack_orig_pfns(buffer, ©_bm, &zero_bm); if (error) return error; if (handle->cur == nr_meta_pages + 1) { - error = prepare_image(&orig_bm, ©_bm); + error = prepare_image(&orig_bm, ©_bm, &zero_bm); if (error) return error; chain_init(&ca, GFP_ATOMIC, PG_SAFE); memory_bm_position_reset(&orig_bm); + memory_bm_position_reset(&zero_bm); restore_pblist = NULL; handle->buffer = get_buffer(&orig_bm, &ca); handle->sync_read = 0; @@ -2738,6 +2841,14 @@ int snapshot_write_next(struct snapshot_handle *handle) handle->sync_read = 0; } handle->cur++; + + /* Zero pages were not included in the image, memset it and move on. */ + if (handle->cur > nr_meta_pages + 1 && + memory_bm_test_bit(&zero_bm, memory_bm_get_current(&orig_bm))) { + memset(handle->buffer, 0, PAGE_SIZE); + goto next; + } + return PAGE_SIZE; } @@ -2754,7 +2865,7 @@ void snapshot_write_finalize(struct snapshot_handle *handle) copy_last_highmem_page(); hibernate_restore_protect_page(handle->buffer); /* Do that only if we have loaded the image entirely */ - if (handle->cur > 1 && handle->cur > nr_meta_pages + nr_copy_pages) { + if (handle->cur > 1 && handle->cur > nr_meta_pages + nr_copy_pages + nr_zero_pages) { memory_bm_recycle(&orig_bm); free_highmem_data(); } @@ -2763,7 +2874,7 @@ void snapshot_write_finalize(struct snapshot_handle *handle) int snapshot_image_loaded(struct snapshot_handle *handle) { return !(!nr_copy_pages || !last_highmem_page_copied() || - handle->cur <= nr_meta_pages + nr_copy_pages); + handle->cur <= nr_meta_pages + nr_copy_pages + nr_zero_pages); } #ifdef CONFIG_HIGHMEM |