path: root/Documentation
diff options
authorJorge Ramirez-Ortiz <jorge.ramirez-ortiz@linaro.org>2015-05-25 19:46:50 -0400
committerKevin Hilman <khilman@linaro.org>2015-05-26 09:28:55 -0700
commit646fe96c67a5fcc2cfffb7326b2299f2714f7f27 (patch)
tree238261a9ef88cd4849235db8e08dd2ab32f6c3c5 /Documentation
parentee22524dbe4fcbaa8186296d197e73982a935565 (diff)
arm64: topology: fix cpu power calculationv3.10/topic/arm64-hmp
This commit sets the power of the average CPU in SMP systems to SCHED_CAPACITY_SCALE. Ignoring the condition "min_capacity==max_capacity" causes the function update_cpu_power( .. ) to generate out of range values. This is because the default value of middle_capacity is used in the final calculation instead of a valid scaling factor. Incidentally, when out of range values are generated and if SCHED_FEAT(ARCH_POWER) is true, the load balancing algorithm makes incorrect scheduling decisions typically overallocating all the work on one of the CPU cores. This proposed solution to arm64 is in line with the upstream solution present in arm32 since the commit below was merged: * SHA: 816a8de0017f16c32e747abc5367bf379515b20a * From: Sudeep KarkadaNagesha <sudeep.karkadanagesha@arm.com> * Date: Mon, 17 Jun 2013 14:20:00 +0100 * Subject: ARM: topology: remove hwid/MPIDR dependency from cpu_capac Signed-off-by: Jorge Ramirez-Ortiz <jorge.ramirez-ortiz@linaro.org> Acked-by: Vincent Guittot <vincent.guittot@linaro.org> Signed-off-by: Kevin Hilman <khilman@linaro.org>
Diffstat (limited to 'Documentation')
0 files changed, 0 insertions, 0 deletions