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Wyatt IV" , John Kacur , Thomas Renninger Cc: linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, Shuah Khan References: <5ff19049-a83a-4ef9-9cae-b97438fb3e77@linuxfoundation.org> <20260528153248.4114324-1-jaskiewiczteo@gmail.com> <9e4994be-008d-4c0b-9bb0-1ff782ad00f5@linuxfoundation.org> Content-Language: en-US From: Shuah Khan In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit On 6/17/26 22:18, Mateusz Jaśkiewicz wrote: > > So when you tried to write it worked looks like. The new > Please follow the kernel mailing list convention of posting at the bottom of the message you are replying you instead adding your response at the top. You can find the details in the kernel documentation. > What I meant by "silent failure" is the situation, when we call a function and it just returns success without doing anything (the situation with current implementation). > > > > value is 1 - what was it before you ran echo 1? > > It was 0 before. That being said there are zones that after writing 0 to them remained 1. Should I add check for this and fail if the value remains unchanged despite intention? Okay so in this case it worked the way it should and the value changed. When writing 0 (echo 0) to the file, did you see a message that says "not supported" I would like to see an concrete use-case for adding the set enable API. We added this stub when SWIG support was added. powercap_set_enabled() could return ENOTSUPP instead of 0 if we don't have a concrete use-case that uses this API. Also if you are looking to improve things cpupower, looks like sysfs_read_file() could be improved. The return values are inconsistent and confusing. In some return values aren't checked. thanks, -- Shuah