From: Dmitry Safonov <d.safonov@xxxxxxxxxxxxxxxxxxx> Here are two functions that provide interface to compute/get used size and size of biggest free chunk in cma region. Add that information to debugfs. Signed-off-by: Dmitry Safonov <d.safonov@xxxxxxxxxxxxxxxxxxx> Signed-off-by: Stefan Strogin <stefan.strogin@xxxxxxxxx> Acked-by: Michal Nazarewicz <mina86@xxxxxxxxxx> --- Took out from the patch set "mm: cma: add some debug information for CMA" v4 (http://thread.gmane.org/gmane.linux.kernel.mm/129903) because of probable uselessness of the most part of the set. include/linux/cma.h | 2 ++ mm/cma.c | 30 ++++++++++++++++++++++++++++++ mm/cma_debug.c | 24 ++++++++++++++++++++++++ 3 files changed, 56 insertions(+) diff --git a/include/linux/cma.h b/include/linux/cma.h index f7ef093..1231f50 100644 --- a/include/linux/cma.h +++ b/include/linux/cma.h @@ -18,6 +18,8 @@ struct cma; extern unsigned long totalcma_pages; extern phys_addr_t cma_get_base(const struct cma *cma); extern unsigned long cma_get_size(const struct cma *cma); +extern unsigned long cma_get_used(struct cma *cma); +extern unsigned long cma_get_maxchunk(struct cma *cma); extern int __init cma_declare_contiguous(phys_addr_t base, phys_addr_t size, phys_addr_t limit, diff --git a/mm/cma.c b/mm/cma.c index 3a7a67b..d839011 100644 --- a/mm/cma.c +++ b/mm/cma.c @@ -53,6 +53,36 @@ unsigned long cma_get_size(const struct cma *cma) return cma->count << PAGE_SHIFT; } +unsigned long cma_get_used(struct cma *cma) +{ + unsigned long ret = 0; + + mutex_lock(&cma->lock); + /* pages counter is smaller than sizeof(int) */ + ret = bitmap_weight(cma->bitmap, (int)cma->count); + mutex_unlock(&cma->lock); + + return ret << cma->order_per_bit; +} + +unsigned long cma_get_maxchunk(struct cma *cma) +{ + unsigned long maxchunk = 0; + unsigned long start, end = 0; + + mutex_lock(&cma->lock); + for (;;) { + start = find_next_zero_bit(cma->bitmap, cma->count, end); + if (start >= cma->count) + break; + end = find_next_bit(cma->bitmap, cma->count, start); + maxchunk = max(end - start, maxchunk); + } + mutex_unlock(&cma->lock); + + return maxchunk << cma->order_per_bit; +} + static unsigned long cma_bitmap_aligned_mask(const struct cma *cma, int align_order) { diff --git a/mm/cma_debug.c b/mm/cma_debug.c index ec915e6..984cedd 100644 --- a/mm/cma_debug.c +++ b/mm/cma_debug.c @@ -33,6 +33,28 @@ static int cma_debugfs_get(void *data, u64 *val) DEFINE_SIMPLE_ATTRIBUTE(cma_debugfs_fops, cma_debugfs_get, NULL, "%llu\n"); +static int cma_used_get(void *data, u64 *val) +{ + struct cma *cma = data; + + *val = cma_get_used(cma); + + return 0; +} + +DEFINE_SIMPLE_ATTRIBUTE(cma_used_fops, cma_used_get, NULL, "%llu\n"); + +static int cma_maxchunk_get(void *data, u64 *val) +{ + struct cma *cma = data; + + *val = cma_get_maxchunk(cma); + + return 0; +} + +DEFINE_SIMPLE_ATTRIBUTE(cma_maxchunk_fops, cma_maxchunk_get, NULL, "%llu\n"); + static void cma_add_to_cma_mem_list(struct cma *cma, struct cma_mem *mem) { spin_lock(&cma->mem_head_lock); @@ -149,6 +171,8 @@ static void cma_debugfs_add_one(struct cma *cma, int idx) &cma->count, &cma_debugfs_fops); debugfs_create_file("order_per_bit", S_IRUGO, tmp, &cma->order_per_bit, &cma_debugfs_fops); + debugfs_create_file("used", S_IRUGO, tmp, cma, &cma_used_fops); + debugfs_create_file("maxchunk", S_IRUGO, tmp, cma, &cma_maxchunk_fops); u32s = DIV_ROUND_UP(cma_bitmap_maxno(cma), BITS_PER_BYTE * sizeof(u32)); debugfs_create_u32_array("bitmap", S_IRUGO, tmp, (u32*)cma->bitmap, u32s); -- 2.1.0 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>