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

From: Mathieu Desnoyers
Date: Tue Jun 05 2018 - 08:51:18 EST


----- On Jun 5, 2018, at 1:18 AM, Michael Ellerman mpe@xxxxxxxxxxxxxx wrote:

> Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx> writes:
>
>> From: Boqun Feng <boqun.feng@xxxxxxxxx>
>>
>> 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@xxxxxxxxx>
>> Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx>
>> CC: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx>
>> CC: Paul Mackerras <paulus@xxxxxxxxx>
>> CC: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
>> CC: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
>> CC: "Paul E. McKenney" <paulmck@xxxxxxxxxxxxxxxxxx>
>> CC: linuxppc-dev@xxxxxxxxxxxxxxxx
>> ---
>> 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@xxxxxxxxxxxxxx> (powerpc)

Added your ack to the series, thanks!

Mathieu

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