Re: [PATCH 1/5] staging: android: lowmemorykiller: Add config option to support oom_adj values

David Rientjes
2013-02-27T23:12:58Z

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On Wed, 27 Feb 2013, Arve Hjønnevåg wrote:

> > Umm, writes to /proc/pid/oom_adj already are converted to the
> > /proc/pid/oom_score_adj scale linearly. Heavy NACK to this patch since
> > oom_adj is completely deprecated.
>
> I know it is deprecated, but your change, staging: android,
> lowmemorykiller: convert to use oom_score_adj, broke existing
> user-space code that still write to /proc/pid/oom_adj. This option
> lets you build a kernel that supports our user-space code until that
> user-space has been converted to use /proc/pid/oom_score_adj.
>

As stated, writes to /proc/pid/oom_adj already are converted to a linear
scale and stored in /proc/pid/oom_score_adj. This is done with

oom_adj == 15 -> oom_score_adj = 1000
oom_adj != 15 -> oom_score_adj = (oom_adj * -1000) / -17

since the maximum oom_score_adj is 1000 and the minimum oom_adj is -17.

How does this not work as needed?