Commit Graph

2 Commits

Author SHA1 Message Date
Bruce Rogers d69748463c sys_membarrier: fix up include directives
Our rule right now is to use <> for external headers only.
util/sys_membarrier.c violates that. Fix it up.

Signed-off-by: Bruce Rogers <brogers@suse.com>
Message-Id: <20180329151018.15319-1-brogers@suse.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-04-05 14:37:38 +02:00
Paolo Bonzini a40161cbe9 membarrier: add --enable-membarrier
Actually enable the global memory barriers if supported by the OS.
Because only recent versions of Linux include the support, they
are disabled by default.  Note that it also has to be disabled
for QEMU to run under Wine.

Before this patch, rcutorture reports 85 ns/read for my machine,
after the patch it reports 12.5 ns/read.  On the other hand updates
go from 50 *micro*seconds to 20 *milli*seconds.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2018-03-12 16:12:47 +01:00