From 2e32b947606daa642a28bfb9b57e9702cfc9a8b3 Mon Sep 17 00:00:00 2001 From: Dmitry Safonov Date: Wed, 15 Apr 2015 16:14:59 -0700 Subject: [PATCH] mm: cma: add functions to get region pages counters 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. [akpm@linux-foundation.org: move debug code from cma.c into cma_debug.c] [stefan.strogin@gmail.com: move code from cma_get_used() and cma_get_maxchunk() to cma_used_get() and cma_maxchunk_get()] Signed-off-by: Dmitry Safonov Signed-off-by: Stefan Strogin Acked-by: Michal Nazarewicz Cc: Marek Szyprowski Cc: Joonsoo Kim Cc: Pintu Kumar Cc: Weijie Yang Cc: Laurent Pinchart Cc: Vyacheslav Tyrtov Cc: Aleksei Mateosian Signed-off-by: Stefan Strogin Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/cma_debug.c | 40 ++++++++++++++++++++++++++++++++++++++++ 1 file changed, 40 insertions(+) diff --git a/mm/cma_debug.c b/mm/cma_debug.c index 0b377536ccde..a040bfb132c3 100644 --- a/mm/cma_debug.c +++ b/mm/cma_debug.c @@ -33,6 +33,44 @@ 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; + unsigned long used; + + mutex_lock(&cma->lock); + /* pages counter is smaller than sizeof(int) */ + used = bitmap_weight(cma->bitmap, (int)cma->count); + mutex_unlock(&cma->lock); + *val = (u64)used << cma->order_per_bit; + + 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; + 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); + *val = (u64)maxchunk << cma->order_per_bit; + + 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 +187,8 @@ 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); -- 2.39.5