[RFC PATCH for 4.18 10/16] powerpc: Wire up restartable sequences system call

[Mathieu Desnoyers]

----- On Jun 5, 2018, at 1:18 AM, Michael Ellerman mpe at ellerman.id.au wrote:

> Mathieu Desnoyers <mathieu.desnoyers at efficios.com> writes:
> 
>> From: Boqun Feng <boqun.feng at gmail.com>
>>
>> Wire up the rseq system call on powerpc.
>>
>> This provides an ABI improving the speed of a user-space getcpu
>> operation on powerpc by skipping the getcpu system call on the fast
>> path, as well as improving the speed of user-space operations on per-cpu
>> data compared to using load-reservation/store-conditional atomics.
>>
>> Signed-off-by: Boqun Feng <boqun.feng at gmail.com>
>> Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers at efficios.com>
>> CC: Benjamin Herrenschmidt <benh at kernel.crashing.org>
>> CC: Paul Mackerras <paulus at samba.org>
>> CC: Michael Ellerman <mpe at ellerman.id.au>
>> CC: Peter Zijlstra <peterz at infradead.org>
>> CC: "Paul E. McKenney" <paulmck at linux.vnet.ibm.com>
>> CC: linuxppc-dev at lists.ozlabs.org
>> ---
>>  arch/powerpc/include/asm/systbl.h      | 1 +
>>  arch/powerpc/include/asm/unistd.h      | 2 +-
>>  arch/powerpc/include/uapi/asm/unistd.h | 1 +
>>  3 files changed, 3 insertions(+), 1 deletion(-)
> 
> Looks fine to me.
> 
> I don't have any other new syscalls in my next, so this should not
> conflict with anything for 4.18.
> 
> Acked-by: Michael Ellerman <mpe at ellerman.id.au> (powerpc)

Added your ack to the series, thanks!

Mathieu

-- 
Mathieu Desnoyers
EfficiOS Inc.
http://www.efficios.com