2010-01-07 22:36:37

by Christoph Lameter

[permalink] [raw]
Subject: [RFC local_t removal V2 0/3] Remove local_t

Current -next has only the trace subsystem left as a user of local_t

Tracing uses local_t for per cpu safe atomic operations in the form
of cmpxchg and additions.

This patchset removes unused function in local.h and then genericizes
local.h by removing local_t. This results in a very small set of
functions.

"long" is used for now instead of local_t. With some additional work it
would be possible to pass arbitrary types to local_xx() function like
cmpxchg_local() and the this_cpu_xx() functions. Maybe a more flexible
way of handling local_xx() would allow the use of these functions in
other kernel subsystems.

Still RFC state. Lots of stuff todo. Compiles on my box.

V1->V2
- Preserve local.h
- Add a rationale why the remaining functions are useful and how
they differ from this_cpu_xx.