On Tue, Sep 04, 2018 at 05:18:48PM +0200, Andrew Jones wrote:
On Tue, Sep 04, 2018 at 03:22:36PM +0200, Igor Mammedov wrote:
commit (5cdc9b76e3 vl.c: Remove dead assignment) removed sockets calculation when 'sockets' weren't provided on CLI since there wasn't any users for it back then. Exiting checks are neither reachable } else if (sockets * cores * threads < cpus) { or nor triggable if (sockets * cores * threads > max_cpus) so we weren't noticing wrong topology since then, since users recalculate sockets adhoc on their own.
However with deprecation check it becomes noticable, for example -smp 2 will start printing warning: "warning: Invalid CPU topology deprecated: sockets (1) * cores (1) * threads (1) != maxcpus (2)" calculating sockets if they weren't specified.
Fix it by returning back sockets calculation if it's omited on CLI.
Signed-off-by: Igor Mammedov <imammedo@redhat.com> --- vl.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/vl.c b/vl.c index 7fd700e..333d638 100644 --- a/vl.c +++ b/vl.c @@ -1210,11 +1210,14 @@ static void smp_parse(QemuOpts *opts)
/* compute missing values, prefer sockets over cores over threads */ if (cpus == 0 || sockets == 0) { - sockets = sockets > 0 ? sockets : 1; cores = cores > 0 ? cores : 1; threads = threads > 0 ? threads : 1; if (cpus == 0) { + sockets = sockets > 0 ? sockets : 1; cpus = cores * threads * sockets; + } else { + max_cpus = qemu_opt_get_number(opts, "maxcpus", cpus); + sockets = !sockets ? max_cpus / (cores * threads) : sockets;
Why the !sockets check here? If we have reached this statement we know that (cpus == 0 || sockets == 0) is true and (cpus == 0) is false, so sockets is guaranteed to be 0. Sorry for not spotting this earlier.
} } else if (cores == 0) { threads = threads > 0 ? threads : 1; -- 2.7.4
Reviewed-by: Andrew Jones <drjones@redhat.com>
-- Eduardo