linux/mm/cma_debug.c
Laura Abbott f318dd083c cma: Store a name in the cma structure
Frameworks that may want to enumerate CMA heaps (e.g. Ion) will find it
useful to have an explicit name attached to each region. Store the name
in each CMA structure.

Signed-off-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-04-18 20:41:12 +02:00

207 lines
4.5 KiB
C

/*
* CMA DebugFS Interface
*
* Copyright (c) 2015 Sasha Levin <sasha.levin@oracle.com>
*/
#include <linux/debugfs.h>
#include <linux/cma.h>
#include <linux/list.h>
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/mm_types.h>
#include "cma.h"
struct cma_mem {
struct hlist_node node;
struct page *p;
unsigned long n;
};
static struct dentry *cma_debugfs_root;
static int cma_debugfs_get(void *data, u64 *val)
{
unsigned long *p = data;
*val = *p;
return 0;
}
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_bitmap_maxno(cma));
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;
unsigned long bitmap_maxno = cma_bitmap_maxno(cma);
mutex_lock(&cma->lock);
for (;;) {
start = find_next_zero_bit(cma->bitmap, bitmap_maxno, end);
if (start >= cma->count)
break;
end = find_next_bit(cma->bitmap, bitmap_maxno, 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);
hlist_add_head(&mem->node, &cma->mem_head);
spin_unlock(&cma->mem_head_lock);
}
static struct cma_mem *cma_get_entry_from_list(struct cma *cma)
{
struct cma_mem *mem = NULL;
spin_lock(&cma->mem_head_lock);
if (!hlist_empty(&cma->mem_head)) {
mem = hlist_entry(cma->mem_head.first, struct cma_mem, node);
hlist_del_init(&mem->node);
}
spin_unlock(&cma->mem_head_lock);
return mem;
}
static int cma_free_mem(struct cma *cma, int count)
{
struct cma_mem *mem = NULL;
while (count) {
mem = cma_get_entry_from_list(cma);
if (mem == NULL)
return 0;
if (mem->n <= count) {
cma_release(cma, mem->p, mem->n);
count -= mem->n;
kfree(mem);
} else if (cma->order_per_bit == 0) {
cma_release(cma, mem->p, count);
mem->p += count;
mem->n -= count;
count = 0;
cma_add_to_cma_mem_list(cma, mem);
} else {
pr_debug("cma: cannot release partial block when order_per_bit != 0\n");
cma_add_to_cma_mem_list(cma, mem);
break;
}
}
return 0;
}
static int cma_free_write(void *data, u64 val)
{
int pages = val;
struct cma *cma = data;
return cma_free_mem(cma, pages);
}
DEFINE_SIMPLE_ATTRIBUTE(cma_free_fops, NULL, cma_free_write, "%llu\n");
static int cma_alloc_mem(struct cma *cma, int count)
{
struct cma_mem *mem;
struct page *p;
mem = kzalloc(sizeof(*mem), GFP_KERNEL);
if (!mem)
return -ENOMEM;
p = cma_alloc(cma, count, 0, GFP_KERNEL);
if (!p) {
kfree(mem);
return -ENOMEM;
}
mem->p = p;
mem->n = count;
cma_add_to_cma_mem_list(cma, mem);
return 0;
}
static int cma_alloc_write(void *data, u64 val)
{
int pages = val;
struct cma *cma = data;
return cma_alloc_mem(cma, pages);
}
DEFINE_SIMPLE_ATTRIBUTE(cma_alloc_fops, NULL, cma_alloc_write, "%llu\n");
static void cma_debugfs_add_one(struct cma *cma, int idx)
{
struct dentry *tmp;
char name[16];
int u32s;
sprintf(name, "cma-%s", cma->name);
tmp = debugfs_create_dir(name, cma_debugfs_root);
debugfs_create_file("alloc", S_IWUSR, tmp, cma,
&cma_alloc_fops);
debugfs_create_file("free", S_IWUSR, tmp, cma,
&cma_free_fops);
debugfs_create_file("base_pfn", S_IRUGO, tmp,
&cma->base_pfn, &cma_debugfs_fops);
debugfs_create_file("count", S_IRUGO, tmp,
&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);
}
static int __init cma_debugfs_init(void)
{
int i;
cma_debugfs_root = debugfs_create_dir("cma", NULL);
if (!cma_debugfs_root)
return -ENOMEM;
for (i = 0; i < cma_area_count; i++)
cma_debugfs_add_one(&cma_areas[i], i);
return 0;
}
late_initcall(cma_debugfs_init);