To pave the way for the functional improvement in later patches, make some refactor/cleanup for the smp parsers, including using local maxcpus instead of ms->smp.max_cpus in the calculation, defaulting dies to 0 initially like other members, cleanup the sanity check for dies.
We actually also fix a hidden defect by avoiding directly using the provided *zero value* in the calculation, which could cause a segment fault (e.g. using dies=0 in the calculation). Signed-off-by: Yanan Wang <wangyana...@huawei.com> Reviewed-by: Andrew Jones <drjo...@redhat.com> --- hw/core/machine.c | 18 ++++++++++-------- hw/i386/pc.c | 23 ++++++++++++++--------- 2 files changed, 24 insertions(+), 17 deletions(-) diff --git a/hw/core/machine.c b/hw/core/machine.c index 711e83db54..cf9cf53911 100644 --- a/hw/core/machine.c +++ b/hw/core/machine.c @@ -752,8 +752,9 @@ static void smp_parse(MachineState *ms, SMPConfiguration *config, Error **errp) unsigned sockets = config->has_sockets ? config->sockets : 0; unsigned cores = config->has_cores ? config->cores : 0; unsigned threads = config->has_threads ? config->threads : 0; + unsigned maxcpus = config->has_maxcpus ? config->maxcpus : 0; - if (config->has_dies && config->dies != 0 && config->dies != 1) { + if (config->has_dies && config->dies > 1) { error_setg(errp, "dies not supported by this machine's CPU topology"); return; } @@ -766,8 +767,8 @@ static void smp_parse(MachineState *ms, SMPConfiguration *config, Error **errp) sockets = sockets > 0 ? sockets : 1; cpus = cores * threads * sockets; } else { - ms->smp.max_cpus = config->has_maxcpus ? config->maxcpus : cpus; - sockets = ms->smp.max_cpus / (cores * threads); + maxcpus = maxcpus > 0 ? maxcpus : cpus; + sockets = maxcpus / (cores * threads); } } else if (cores == 0) { threads = threads > 0 ? threads : 1; @@ -784,26 +785,27 @@ static void smp_parse(MachineState *ms, SMPConfiguration *config, Error **errp) return; } - ms->smp.max_cpus = config->has_maxcpus ? config->maxcpus : cpus; + maxcpus = maxcpus > 0 ? maxcpus : cpus; - if (ms->smp.max_cpus < cpus) { + if (maxcpus < cpus) { error_setg(errp, "maxcpus must be equal to or greater than smp"); return; } - if (sockets * cores * threads != ms->smp.max_cpus) { + if (sockets * cores * threads != maxcpus) { error_setg(errp, "Invalid CPU topology: " "sockets (%u) * cores (%u) * threads (%u) " "!= maxcpus (%u)", sockets, cores, threads, - ms->smp.max_cpus); + maxcpus); return; } ms->smp.cpus = cpus; + ms->smp.sockets = sockets; ms->smp.cores = cores; ms->smp.threads = threads; - ms->smp.sockets = sockets; + ms->smp.max_cpus = maxcpus; } static void machine_get_smp(Object *obj, Visitor *v, const char *name, diff --git a/hw/i386/pc.c b/hw/i386/pc.c index 7e523b913c..8599a9b527 100644 --- a/hw/i386/pc.c +++ b/hw/i386/pc.c @@ -718,9 +718,13 @@ static void pc_smp_parse(MachineState *ms, SMPConfiguration *config, Error **err { unsigned cpus = config->has_cpus ? config->cpus : 0; unsigned sockets = config->has_sockets ? config->sockets : 0; - unsigned dies = config->has_dies ? config->dies : 1; + unsigned dies = config->has_dies ? config->dies : 0; unsigned cores = config->has_cores ? config->cores : 0; unsigned threads = config->has_threads ? config->threads : 0; + unsigned maxcpus = config->has_maxcpus ? config->maxcpus : 0; + + /* directly default dies to 1 if it's omitted */ + dies = dies > 0 ? dies : 1; /* compute missing values, prefer sockets over cores over threads */ if (cpus == 0 || sockets == 0) { @@ -730,8 +734,8 @@ static void pc_smp_parse(MachineState *ms, SMPConfiguration *config, Error **err sockets = sockets > 0 ? sockets : 1; cpus = cores * threads * dies * sockets; } else { - ms->smp.max_cpus = config->has_maxcpus ? config->maxcpus : cpus; - sockets = ms->smp.max_cpus / (cores * threads * dies); + maxcpus = maxcpus > 0 ? maxcpus : cpus; + sockets = maxcpus / (dies * cores * threads); } } else if (cores == 0) { threads = threads > 0 ? threads : 1; @@ -748,27 +752,28 @@ static void pc_smp_parse(MachineState *ms, SMPConfiguration *config, Error **err return; } - ms->smp.max_cpus = config->has_maxcpus ? config->maxcpus : cpus; + maxcpus = maxcpus > 0 ? maxcpus : cpus; - if (ms->smp.max_cpus < cpus) { + if (maxcpus < cpus) { error_setg(errp, "maxcpus must be equal to or greater than smp"); return; } - if (sockets * dies * cores * threads != ms->smp.max_cpus) { + if (sockets * dies * cores * threads != maxcpus) { error_setg(errp, "Invalid CPU topology deprecated: " "sockets (%u) * dies (%u) * cores (%u) * threads (%u) " "!= maxcpus (%u)", sockets, dies, cores, threads, - ms->smp.max_cpus); + maxcpus); return; } ms->smp.cpus = cpus; - ms->smp.cores = cores; - ms->smp.threads = threads; ms->smp.sockets = sockets; ms->smp.dies = dies; + ms->smp.cores = cores; + ms->smp.threads = threads; + ms->smp.max_cpus = maxcpus; } static -- 2.23.0