----- On Oct 6, 2017, at 5:08 PM, Paul E. McKenney paul...@linux.vnet.ibm.com wrote:
> On Thu, Oct 05, 2017 at 06:33:26PM -0400, Mathieu Desnoyers wrote: >> Architectures without membarrier hooks don't need to emit the >> empty membarrier_arch_switch_mm() static inline when >> CONFIG_MEMBARRIER=y. >> >> Adapt the CONFIG_MEMBARRIER=n counterpart to only emit the empty >> membarrier_arch_switch_mm() for architectures with membarrier hooks. >> >> Reported-by: Nicholas Piggin <npig...@gmail.com> >> Signed-off-by: Mathieu Desnoyers <mathieu.desnoy...@efficios.com> > > Queued for further review and testing, targeting v4.15. Please let me > know if you need it sooner. Hi Paul, Given that the following patch in this patchset (2/2) "Fix: membarrier: Handle CLONE_VM + !CLONE_THREAD correctly on powerpc" is based on this patch, and that the fix needs to go into 4.14, I would recommend queuing both patches for 4.14 is possible. Otherwise I could try swapping the order of the two patches if needed, but since both are touching nearby code areas, rebasing is not straightforward. Thanks, Mathieu > > Thanx, Paul > >> CC: Peter Zijlstra <pet...@infradead.org> >> CC: Paul E. McKenney <paul...@linux.vnet.ibm.com> >> CC: Boqun Feng <boqun.f...@gmail.com> >> CC: Andrew Hunter <a...@google.com> >> CC: Maged Michael <maged.mich...@gmail.com> >> CC: gro...@google.com >> CC: Avi Kivity <a...@scylladb.com> >> CC: Benjamin Herrenschmidt <b...@kernel.crashing.org> >> CC: Paul Mackerras <pau...@samba.org> >> CC: Michael Ellerman <m...@ellerman.id.au> >> CC: Dave Watson <davejwat...@fb.com> >> CC: Alan Stern <st...@rowland.harvard.edu> >> CC: Will Deacon <will.dea...@arm.com> >> CC: Andy Lutomirski <l...@kernel.org> >> CC: Ingo Molnar <mi...@redhat.com> >> CC: Alexander Viro <v...@zeniv.linux.org.uk> >> CC: linuxppc-dev@lists.ozlabs.org >> CC: linux-a...@vger.kernel.org >> --- >> include/linux/sched/mm.h | 6 ++---- >> 1 file changed, 2 insertions(+), 4 deletions(-) >> >> diff --git a/include/linux/sched/mm.h b/include/linux/sched/mm.h >> index d5a9ab8f3836..b2767ecb21a8 100644 >> --- a/include/linux/sched/mm.h >> +++ b/include/linux/sched/mm.h >> @@ -215,10 +215,6 @@ static inline void memalloc_noreclaim_restore(unsigned >> int >> flags) >> #ifdef CONFIG_ARCH_HAS_MEMBARRIER_HOOKS >> #include <asm/membarrier.h> >> #else >> -static inline void membarrier_arch_switch_mm(struct mm_struct *prev, >> - struct mm_struct *next, struct task_struct *tsk) >> -{ >> -} >> static inline void membarrier_arch_fork(struct task_struct *t, >> unsigned long clone_flags) >> { >> @@ -247,10 +243,12 @@ static inline void membarrier_execve(struct task_struct >> *t) >> membarrier_arch_execve(t); >> } >> #else >> +#ifdef CONFIG_ARCH_HAS_MEMBARRIER_HOOKS >> static inline void membarrier_arch_switch_mm(struct mm_struct *prev, >> struct mm_struct *next, struct task_struct *tsk) >> { >> } >> +#endif >> static inline void membarrier_fork(struct task_struct *t, >> unsigned long clone_flags) >> { >> -- >> 2.11.0 -- Mathieu Desnoyers EfficiOS Inc. http://www.efficios.com