summaryrefslogtreecommitdiff
path: root/kernel/trace/ring_buffer.c
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/trace/ring_buffer.c')
-rw-r--r--kernel/trace/ring_buffer.c66
1 files changed, 36 insertions, 30 deletions
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index b0c7aa4..731201b 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -997,15 +997,21 @@ static int rb_allocate_pages(struct ring_buffer_per_cpu *cpu_buffer,
unsigned nr_pages)
{
struct buffer_page *bpage, *tmp;
- unsigned long addr;
LIST_HEAD(pages);
unsigned i;
WARN_ON(!nr_pages);
for (i = 0; i < nr_pages; i++) {
+ struct page *page;
+ /*
+ * __GFP_NORETRY flag makes sure that the allocation fails
+ * gracefully without invoking oom-killer and the system is
+ * not destabilized.
+ */
bpage = kzalloc_node(ALIGN(sizeof(*bpage), cache_line_size()),
- GFP_KERNEL, cpu_to_node(cpu_buffer->cpu));
+ GFP_KERNEL | __GFP_NORETRY,
+ cpu_to_node(cpu_buffer->cpu));
if (!bpage)
goto free_pages;
@@ -1013,10 +1019,11 @@ static int rb_allocate_pages(struct ring_buffer_per_cpu *cpu_buffer,
list_add(&bpage->list, &pages);
- addr = __get_free_page(GFP_KERNEL);
- if (!addr)
+ page = alloc_pages_node(cpu_to_node(cpu_buffer->cpu),
+ GFP_KERNEL | __GFP_NORETRY, 0);
+ if (!page)
goto free_pages;
- bpage->page = (void *)addr;
+ bpage->page = page_address(page);
rb_init_page(bpage->page);
}
@@ -1045,7 +1052,7 @@ rb_allocate_cpu_buffer(struct ring_buffer *buffer, int cpu)
{
struct ring_buffer_per_cpu *cpu_buffer;
struct buffer_page *bpage;
- unsigned long addr;
+ struct page *page;
int ret;
cpu_buffer = kzalloc_node(ALIGN(sizeof(*cpu_buffer), cache_line_size()),
@@ -1067,10 +1074,10 @@ rb_allocate_cpu_buffer(struct ring_buffer *buffer, int cpu)
rb_check_bpage(cpu_buffer, bpage);
cpu_buffer->reader_page = bpage;
- addr = __get_free_page(GFP_KERNEL);
- if (!addr)
+ page = alloc_pages_node(cpu_to_node(cpu), GFP_KERNEL, 0);
+ if (!page)
goto fail_free_reader;
- bpage->page = (void *)addr;
+ bpage->page = page_address(page);
rb_init_page(bpage->page);
INIT_LIST_HEAD(&cpu_buffer->reader_page->list);
@@ -1314,7 +1321,6 @@ int ring_buffer_resize(struct ring_buffer *buffer, unsigned long size)
unsigned nr_pages, rm_pages, new_pages;
struct buffer_page *bpage, *tmp;
unsigned long buffer_size;
- unsigned long addr;
LIST_HEAD(pages);
int i, cpu;
@@ -1375,16 +1381,24 @@ int ring_buffer_resize(struct ring_buffer *buffer, unsigned long size)
for_each_buffer_cpu(buffer, cpu) {
for (i = 0; i < new_pages; i++) {
+ struct page *page;
+ /*
+ * __GFP_NORETRY flag makes sure that the allocation
+ * fails gracefully without invoking oom-killer and
+ * the system is not destabilized.
+ */
bpage = kzalloc_node(ALIGN(sizeof(*bpage),
cache_line_size()),
- GFP_KERNEL, cpu_to_node(cpu));
+ GFP_KERNEL | __GFP_NORETRY,
+ cpu_to_node(cpu));
if (!bpage)
goto free_pages;
list_add(&bpage->list, &pages);
- addr = __get_free_page(GFP_KERNEL);
- if (!addr)
+ page = alloc_pages_node(cpu_to_node(cpu),
+ GFP_KERNEL | __GFP_NORETRY, 0);
+ if (!page)
goto free_pages;
- bpage->page = (void *)addr;
+ bpage->page = page_address(page);
rb_init_page(bpage->page);
}
}
@@ -3730,16 +3744,17 @@ EXPORT_SYMBOL_GPL(ring_buffer_swap_cpu);
* Returns:
* The page allocated, or NULL on error.
*/
-void *ring_buffer_alloc_read_page(struct ring_buffer *buffer)
+void *ring_buffer_alloc_read_page(struct ring_buffer *buffer, int cpu)
{
struct buffer_data_page *bpage;
- unsigned long addr;
+ struct page *page;
- addr = __get_free_page(GFP_KERNEL);
- if (!addr)
+ page = alloc_pages_node(cpu_to_node(cpu),
+ GFP_KERNEL | __GFP_NORETRY, 0);
+ if (!page)
return NULL;
- bpage = (void *)addr;
+ bpage = page_address(page);
rb_init_page(bpage);
@@ -3978,20 +3993,11 @@ rb_simple_write(struct file *filp, const char __user *ubuf,
size_t cnt, loff_t *ppos)
{
unsigned long *p = filp->private_data;
- char buf[64];
unsigned long val;
int ret;
- if (cnt >= sizeof(buf))
- return -EINVAL;
-
- if (copy_from_user(&buf, ubuf, cnt))
- return -EFAULT;
-
- buf[cnt] = 0;
-
- ret = strict_strtoul(buf, 10, &val);
- if (ret < 0)
+ ret = kstrtoul_from_user(ubuf, cnt, 10, &val);
+ if (ret)
return ret;
if (val)