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authorMark Brown <broonie@kernel.org>2017-08-30 23:15:31 +0200
committerMark Brown <broonie@kernel.org>2017-08-30 23:15:31 +0200
commitb388dc1f62a9bdd9c4758a0664e61d0f9a9da519 (patch)
tree696fd3c245700ee59ebcf3a65b90f8773b904624 /kernel/trace/ring_buffer.c
parentASoC: remove duplicate definition of dapm_routes/num_dapm_routes (diff)
parentLinux 4.13-rc7 (diff)
downloadlinux-b388dc1f62a9bdd9c4758a0664e61d0f9a9da519.tar.xz
linux-b388dc1f62a9bdd9c4758a0664e61d0f9a9da519.zip
Merge tag 'v4.13-rc7' into asoc-component
Linux 4.13-rc7
Diffstat (limited to 'kernel/trace/ring_buffer.c')
-rw-r--r--kernel/trace/ring_buffer.c24
1 files changed, 14 insertions, 10 deletions
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 4ae268e687fe..81279c6602ff 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -1136,12 +1136,12 @@ static int __rb_allocate_pages(long nr_pages, struct list_head *pages, int cpu)
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.
+ * __GFP_RETRY_MAYFAIL 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 | __GFP_NORETRY,
+ GFP_KERNEL | __GFP_RETRY_MAYFAIL,
cpu_to_node(cpu));
if (!bpage)
goto free_pages;
@@ -1149,7 +1149,7 @@ static int __rb_allocate_pages(long nr_pages, struct list_head *pages, int cpu)
list_add(&bpage->list, pages);
page = alloc_pages_node(cpu_to_node(cpu),
- GFP_KERNEL | __GFP_NORETRY, 0);
+ GFP_KERNEL | __GFP_RETRY_MAYFAIL, 0);
if (!page)
goto free_pages;
bpage->page = page_address(page);
@@ -4386,15 +4386,19 @@ EXPORT_SYMBOL_GPL(ring_buffer_swap_cpu);
* the page that was allocated, with the read page of the buffer.
*
* Returns:
- * The page allocated, or NULL on error.
+ * The page allocated, or ERR_PTR
*/
void *ring_buffer_alloc_read_page(struct ring_buffer *buffer, int cpu)
{
- struct ring_buffer_per_cpu *cpu_buffer = buffer->buffers[cpu];
+ struct ring_buffer_per_cpu *cpu_buffer;
struct buffer_data_page *bpage = NULL;
unsigned long flags;
struct page *page;
+ if (!cpumask_test_cpu(cpu, buffer->cpumask))
+ return ERR_PTR(-ENODEV);
+
+ cpu_buffer = buffer->buffers[cpu];
local_irq_save(flags);
arch_spin_lock(&cpu_buffer->lock);
@@ -4412,7 +4416,7 @@ void *ring_buffer_alloc_read_page(struct ring_buffer *buffer, int cpu)
page = alloc_pages_node(cpu_to_node(cpu),
GFP_KERNEL | __GFP_NORETRY, 0);
if (!page)
- return NULL;
+ return ERR_PTR(-ENOMEM);
bpage = page_address(page);
@@ -4467,8 +4471,8 @@ EXPORT_SYMBOL_GPL(ring_buffer_free_read_page);
*
* for example:
* rpage = ring_buffer_alloc_read_page(buffer, cpu);
- * if (!rpage)
- * return error;
+ * if (IS_ERR(rpage))
+ * return PTR_ERR(rpage);
* ret = ring_buffer_read_page(buffer, &rpage, len, cpu, 0);
* if (ret >= 0)
* process_page(rpage, ret);