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Date: Wed, 4 Apr 2018 19:58:41 -0700
From: Matthew Wilcox <willy@infradead.org>
Subject: Re: [PATCH v1] kernel/trace:check the val against the available mem
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To: Steven Rostedt <rostedt@goodmis.org>
Cc: Michal Hocko <mhocko@kernel.org>, Zhaoyang Huang <huangzhaoyang@gmail.com>, Ingo Molnar <mingo@kernel.org>, linux-kernel@vger.kernel.org, kernel-patch-test@lists.linaro.org, Andrew Morton <akpm@linux-foundation.org>, Joel Fernandes <joelaf@google.com>, linux-mm@kvack.org, Vlastimil Babka <vbabka@suse.cz>

On Wed, Apr 04, 2018 at 11:47:30AM -0400, Steven Rostedt wrote:
> I originally was going to remove the RETRY_MAYFAIL, but adding this
> check (at the end of the loop though) appears to have OOM consistently
> kill this task.
> 
> I still like to keep RETRY_MAYFAIL, because it wont trigger OOM if
> nothing comes in and tries to do an allocation, but instead will fail
> nicely with -ENOMEM.

I still don't get why you want RETRY_MAYFAIL.  You know that tries
*harder* to allocate memory than plain GFP_KERNEL does, right?  And
that seems like the exact opposite of what you want.