From: Heiko Carstens <heiko.carstens@xxxxxxxxxx> The fallback calculation of nthreads did not consider books. In order to avoid division/multiply by/with zero make sure each number used is at least "1". Signed-off-by: Heiko Carstens <heiko.carstens@xxxxxxxxxx> --- sys-utils/lscpu.c | 14 +++++++++----- 1 file changed, 9 insertions(+), 5 deletions(-) --- a/sys-utils/lscpu.c +++ b/sys-utils/lscpu.c @@ -649,17 +649,21 @@ read_topology(struct lscpu_desc *desc, i nthreads = CPU_COUNT_S(setsize, thread_siblings); /* cores within one socket */ ncores = CPU_COUNT_S(setsize, core_siblings) / nthreads; - /* number of sockets within one book */ - nsockets = desc->ncpus / nthreads / ncores; + /* number of sockets within one book. + * Because of odd / non-present cpu maps and to keep + * calculation easy we make sure that nsockets and + * nbooks is at least 1. + */ + nsockets = desc->ncpus / nthreads / ncores ?: 1; /* number of books */ - nbooks = desc->ncpus / nthreads / ncores / nsockets; + nbooks = desc->ncpus / nthreads / ncores / nsockets ?: 1; /* all threads, see also read_basicinfo() - * -- this is fallback for kernels where is not + * -- fallback for kernels without * /sys/devices/system/cpu/online. */ if (!desc->nthreads) - desc->nthreads = nsockets * ncores * nthreads; + desc->nthreads = nbooks * nsockets * ncores * nthreads; /* For each map we make sure that it can have up to ncpus * entries. This is because we cannot reliably calculate the * number of cores, sockets and books on all architectures. -- To unsubscribe from this list: send the line "unsubscribe util-linux" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
