diff options
| -rw-r--r-- | Documentation/ABI/testing/sysfs-kernel-mm-cma | 13 | ||||
| -rw-r--r-- | mm/cma.c | 22 | ||||
| -rw-r--r-- | mm/cma.h | 1 | ||||
| -rw-r--r-- | mm/cma_debug.c | 5 | ||||
| -rw-r--r-- | mm/cma_sysfs.c | 20 |
5 files changed, 51 insertions, 10 deletions
diff --git a/Documentation/ABI/testing/sysfs-kernel-mm-cma b/Documentation/ABI/testing/sysfs-kernel-mm-cma index dfd755201142..aaf2a5d8b13b 100644 --- a/Documentation/ABI/testing/sysfs-kernel-mm-cma +++ b/Documentation/ABI/testing/sysfs-kernel-mm-cma @@ -29,3 +29,16 @@ Date: Feb 2024 Contact: Anshuman Khandual <anshuman.khandual@arm.com> Description: the number of pages CMA API succeeded to release + +What: /sys/kernel/mm/cma/<cma-heap-name>/total_pages +Date: Jun 2024 +Contact: Frank van der Linden <fvdl@google.com> +Description: + The size of the CMA area in pages. + +What: /sys/kernel/mm/cma/<cma-heap-name>/available_pages +Date: Jun 2024 +Contact: Frank van der Linden <fvdl@google.com> +Description: + The number of pages in the CMA area that are still + available for CMA allocation. @@ -86,6 +86,7 @@ static void cma_clear_bitmap(struct cma *cma, unsigned long pfn, spin_lock_irqsave(&cma->lock, flags); bitmap_clear(cma->bitmap, bitmap_no, bitmap_count); + cma->available_count += count; spin_unlock_irqrestore(&cma->lock, flags); } @@ -133,7 +134,7 @@ out_error: free_reserved_page(pfn_to_page(pfn)); } totalcma_pages -= cma->count; - cma->count = 0; + cma->available_count = cma->count = 0; pr_err("CMA area %s could not be activated\n", cma->name); } @@ -206,7 +207,7 @@ int __init cma_init_reserved_mem(phys_addr_t base, phys_addr_t size, snprintf(cma->name, CMA_MAX_NAME, "cma%d\n", cma_area_count); cma->base_pfn = PFN_DOWN(base); - cma->count = size >> PAGE_SHIFT; + cma->available_count = cma->count = size >> PAGE_SHIFT; cma->order_per_bit = order_per_bit; *res_cma = cma; cma_area_count++; @@ -390,7 +391,7 @@ static void cma_debug_show_areas(struct cma *cma) { unsigned long next_zero_bit, next_set_bit, nr_zero; unsigned long start = 0; - unsigned long nr_part, nr_total = 0; + unsigned long nr_part; unsigned long nbits = cma_bitmap_maxno(cma); spin_lock_irq(&cma->lock); @@ -402,12 +403,12 @@ static void cma_debug_show_areas(struct cma *cma) next_set_bit = find_next_bit(cma->bitmap, nbits, next_zero_bit); nr_zero = next_set_bit - next_zero_bit; nr_part = nr_zero << cma->order_per_bit; - pr_cont("%s%lu@%lu", nr_total ? "+" : "", nr_part, + pr_cont("%s%lu@%lu", start ? "+" : "", nr_part, next_zero_bit); - nr_total += nr_part; start = next_zero_bit + nr_zero; } - pr_cont("=> %lu free of %lu total pages\n", nr_total, cma->count); + pr_cont("=> %lu free of %lu total pages\n", cma->available_count, + cma->count); spin_unlock_irq(&cma->lock); } @@ -444,6 +445,14 @@ static struct page *__cma_alloc(struct cma *cma, unsigned long count, for (;;) { spin_lock_irq(&cma->lock); + /* + * If the request is larger than the available number + * of pages, stop right away. + */ + if (count > cma->available_count) { + spin_unlock_irq(&cma->lock); + break; + } bitmap_no = bitmap_find_next_zero_area_off(cma->bitmap, bitmap_maxno, start, bitmap_count, mask, offset); @@ -452,6 +461,7 @@ static struct page *__cma_alloc(struct cma *cma, unsigned long count, break; } bitmap_set(cma->bitmap, bitmap_no, bitmap_count); + cma->available_count -= count; /* * It's safe to drop the lock here. We've marked this region for * our exclusive use. If the migration fails we will take the @@ -13,6 +13,7 @@ struct cma_kobject { struct cma { unsigned long base_pfn; unsigned long count; + unsigned long available_count; unsigned long *bitmap; unsigned int order_per_bit; /* Order of pages represented by one bit */ spinlock_t lock; diff --git a/mm/cma_debug.c b/mm/cma_debug.c index 602fff89b15f..89236f22230a 100644 --- a/mm/cma_debug.c +++ b/mm/cma_debug.c @@ -34,13 +34,10 @@ DEFINE_DEBUGFS_ATTRIBUTE(cma_debugfs_fops, cma_debugfs_get, NULL, "%llu\n"); static int cma_used_get(void *data, u64 *val) { struct cma *cma = data; - unsigned long used; spin_lock_irq(&cma->lock); - /* pages counter is smaller than sizeof(int) */ - used = bitmap_weight(cma->bitmap, (int)cma_bitmap_maxno(cma)); + *val = cma->count - cma->available_count; spin_unlock_irq(&cma->lock); - *val = (u64)used << cma->order_per_bit; return 0; } diff --git a/mm/cma_sysfs.c b/mm/cma_sysfs.c index f50db3973171..97acd3e5a6a5 100644 --- a/mm/cma_sysfs.c +++ b/mm/cma_sysfs.c @@ -62,6 +62,24 @@ static ssize_t release_pages_success_show(struct kobject *kobj, } CMA_ATTR_RO(release_pages_success); +static ssize_t total_pages_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct cma *cma = cma_from_kobj(kobj); + + return sysfs_emit(buf, "%lu\n", cma->count); +} +CMA_ATTR_RO(total_pages); + +static ssize_t available_pages_show(struct kobject *kobj, + struct kobj_attribute *attr, char *buf) +{ + struct cma *cma = cma_from_kobj(kobj); + + return sysfs_emit(buf, "%lu\n", cma->available_count); +} +CMA_ATTR_RO(available_pages); + static void cma_kobj_release(struct kobject *kobj) { struct cma *cma = cma_from_kobj(kobj); @@ -75,6 +93,8 @@ static struct attribute *cma_attrs[] = { &alloc_pages_success_attr.attr, &alloc_pages_fail_attr.attr, &release_pages_success_attr.attr, + &total_pages_attr.attr, + &available_pages_attr.attr, NULL, }; ATTRIBUTE_GROUPS(cma); |