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[73.93.175.39]) by smtp.gmail.com with ESMTPSA id z12sm423456pfn.186.2021.01.11.11.53.32 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 11 Jan 2021 11:53:33 -0800 (PST) Date: Mon, 11 Jan 2021 11:53:23 -0800 From: =?iso-8859-1?Q?J=F6rn?= Engel To: Marco Elver Cc: akpm@linux-foundation.org, glider@google.com, dvyukov@google.com, andreyknvl@google.com, jannh@google.com, mark.rutland@arm.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, kasan-dev@googlegroups.com Subject: Re: [PATCH mm 1/2] kfence: add option to use KFENCE without static keys Message-ID: <20210111195323.GA842777@cork> References: <20210111091544.3287013-1-elver@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20210111091544.3287013-1-elver@google.com> Content-Transfer-Encoding: quoted-printable X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Mon, Jan 11, 2021 at 10:15:43AM +0100, Marco Elver wrote: > For certain usecases, specifically where the sample interval is always > set to a very low value such as 1ms, it can make sense to use a dynamic > branch instead of static branches due to the overhead of toggling a > static branch. I ended up with 100=C2=B5s and couldn't measure a performance problem in = our benchmarks. My results don't have predictive value for anyone else, of course. > Therefore, add a new Kconfig option to remove the static branches and > instead check kfence_allocation_gate if a KFENCE allocation should be > set up. >=20 > Suggested-by: J=C3=B6rn Engel > Signed-off-by: Marco Elver Reviewed-by: J=C3=B6rn Engel J=C3=B6rn -- One of the things I=E2=80=99ve discovered over the years, is that you can create change or you can receive credit =E2=80=93 not both. -- Stephen Downes