From 1501ecc1d89231164b4aecddd0219ed4395b693a Mon Sep 17 00:00:00 2001 From: Stefan Hajnoczi Date: Thu, 23 Jul 2015 13:48:34 +0100 Subject: [PATCH] raw-posix: warn about BDRV_O_NATIVE_AIO if libaio is unavailable raw-posix.c silently ignores BDRV_O_NATIVE_AIO if libaio is unavailable. It is confusing when aio=native performance is identical to aio=threads because the binary was accidentally built without libaio. Print a deprecation warning if -drive aio=native is used with a binary that does not support libaio. There are probably users using aio=native who would be inconvenienced if QEMU suddenly refused to start their guests. In the future this will become an error. Signed-off-by: Stefan Hajnoczi Signed-off-by: Kevin Wolf --- block/raw-posix.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/block/raw-posix.c b/block/raw-posix.c index cc1b8743ac..3a527f0b6b 100644 --- a/block/raw-posix.c +++ b/block/raw-posix.c @@ -519,7 +519,16 @@ static int raw_open_common(BlockDriverState *bs, QDict *options, "future QEMU versions.\n", bs->filename); } -#endif +#else + if (bdrv_flags & BDRV_O_NATIVE_AIO) { + error_printf("WARNING: aio=native was specified for '%s', but " + "is not supported in this build. Falling back to " + "aio=threads.\n" + " This will become an error condition in " + "future QEMU versions.\n", + bs->filename); + } +#endif /* !defined(CONFIG_LINUX_AIO) */ s->has_discard = true; s->has_write_zeroes = true; -- 2.11.4.GIT