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| author | Vaibhav Nagarnaik <vnagarnaik@google.com> | 2011-06-07 17:01:42 -0700 | 
|---|---|---|
| committer | Steven Rostedt <rostedt@goodmis.org> | 2011-06-14 22:48:51 -0400 | 
| commit | d7ec4bfed6c97405c6417970ba06c439e08ab8e3 (patch) | |
| tree | 35272bc4262f70243382d085787765c5e83d6736 /kernel/trace/ring_buffer.c | |
| parent | 22fe9b54d859e53bfbbbdc1a0a77a82bc453927c (diff) | |
| download | olio-linux-3.10-d7ec4bfed6c97405c6417970ba06c439e08ab8e3.tar.xz olio-linux-3.10-d7ec4bfed6c97405c6417970ba06c439e08ab8e3.zip  | |
ring-buffer: Set __GFP_NORETRY flag for ring buffer allocating process
The tracing ring buffer is allocated from kernel memory. While
allocating a large chunk of memory, OOM might happen which destabilizes
the system. Thus random processes might get killed during the
allocation.
This patch adds __GFP_NORETRY flag to the ring buffer allocation calls
to make it fail more gracefully if the system will not be able to
complete the allocation request.
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Vaibhav Nagarnaik <vnagarnaik@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Michael Rubin <mrubin@google.com>
Cc: David Sharp <dhsharp@google.com>
Link: http://lkml.kernel.org/r/1307491302-9236-1-git-send-email-vnagarnaik@google.com
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Diffstat (limited to 'kernel/trace/ring_buffer.c')
| -rw-r--r-- | kernel/trace/ring_buffer.c | 25 | 
1 files changed, 19 insertions, 6 deletions
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index f00ede314eb..731201bf4ac 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -1004,9 +1004,14 @@ static int rb_allocate_pages(struct ring_buffer_per_cpu *cpu_buffer,  	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; @@ -1015,7 +1020,7 @@ static int rb_allocate_pages(struct ring_buffer_per_cpu *cpu_buffer,  		list_add(&bpage->list, &pages);  		page = alloc_pages_node(cpu_to_node(cpu_buffer->cpu), -					GFP_KERNEL, 0); +					GFP_KERNEL | __GFP_NORETRY, 0);  		if (!page)  			goto free_pages;  		bpage->page = page_address(page); @@ -1377,13 +1382,20 @@ 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); -			page = alloc_pages_node(cpu_to_node(cpu), GFP_KERNEL, 0); +			page = alloc_pages_node(cpu_to_node(cpu), +						GFP_KERNEL | __GFP_NORETRY, 0);  			if (!page)  				goto free_pages;  			bpage->page = page_address(page); @@ -3737,7 +3749,8 @@ void *ring_buffer_alloc_read_page(struct ring_buffer *buffer, int cpu)  	struct buffer_data_page *bpage;  	struct page *page; -	page = alloc_pages_node(cpu_to_node(cpu), GFP_KERNEL, 0); +	page = alloc_pages_node(cpu_to_node(cpu), +				GFP_KERNEL | __GFP_NORETRY, 0);  	if (!page)  		return NULL;  |