3:57 p.m.
tree: https://github.com/norov/linux bm-new1
head: 4c8fba87b160a8063bdd06928dbfc058e26a85db
commit: 80216b2d5ee90bb6dea0aaa7224948f6deb3ae83 [2/15] lib/cpumask: replace
cpumask_weight with cpumask_empty where appropriate
config: x86_64-randconfig-a012-20211214
(https://download.01.org/0day-ci/archive/20211215/202112151203.qazbGUpx-lk...)
compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project
b6a2ddb6c8ac29412b1361810972e15221fa021c)
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O
~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/norov/linux/commit/80216b2d5ee90bb6dea0aaa7224948f6deb...
git remote add norov https://github.com/norov/linux
git fetch --no-tags norov bm-new1
git checkout 80216b2d5ee90bb6dea0aaa7224948f6deb3ae83
# save the config file to linux build tree
mkdir build_dir
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir
ARCH=x86_64 SHELL=/bin/bash drivers/infiniband/sw/siw/
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp(a)intel.com>
All warnings (new ones prefixed by >>):
> drivers/infiniband/sw/siw/siw_main.c:196:6: warning: variable
'num_cpus' is used uninitialized whenever 'if' condition is false
[-Wsometimes-uninitialized]
if (cpumask_empty(tx_cpumask)) {
^~~~~~~~~~~~~~~~~~~~~~~~~
drivers/infiniband/sw/siw/siw_main.c:201:7: note: uninitialized use occurs here
if (!num_cpus)
^~~~~~~~
drivers/infiniband/sw/siw/siw_main.c:196:2: note: remove the 'if' if its
condition is always true
if (cpumask_empty(tx_cpumask)) {
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/infiniband/sw/siw/siw_main.c:189:17: note: initialize the variable
'num_cpus' to silence this warning
int i, num_cpus, cpu, min_use, node = sdev->numa_node, tx_cpu = -1;
^
= 0
1 warning generated.
vim +196 drivers/infiniband/sw/siw/siw_main.c
181
182 /*
183 * Choose CPU with least number of active QP's from NUMA node of
184 * TX interface.
185 */
186 int siw_get_tx_cpu(struct siw_device *sdev)
187 {
188 const struct cpumask *tx_cpumask;
189 int i, num_cpus, cpu, min_use, node = sdev->numa_node, tx_cpu = -1;
190
191 if (node < 0)
192 tx_cpumask = cpu_online_mask;
193 else
194 tx_cpumask = siw_cpu_info.tx_valid_cpus[node];
195
196 if (cpumask_empty(tx_cpumask)) {
197 /* no CPU on
this NUMA node */
198 tx_cpumask = cpu_online_mask;
199 num_cpus = cpumask_weight(tx_cpumask);
200 }
201 if (!num_cpus)
202 goto out;
203
204 cpu = cpumask_first(tx_cpumask);
205
206 for (i = 0, min_use = SIW_MAX_QP; i < num_cpus;
207 i++, cpu = cpumask_next(cpu, tx_cpumask)) {
208 int usage;
209
210 /* Skip any cores which have no TX thread */
211 if (!siw_tx_thread[cpu])
212 continue;
213
214 usage = atomic_read(&per_cpu(siw_use_cnt, cpu));
215 if (usage <= min_use) {
216 tx_cpu = cpu;
217 min_use = usage;
218 }
219 }
220 siw_dbg(&sdev->base_dev,
221 "tx cpu %d, node %d, %d qp's\n", tx_cpu, node, min_use);
222
223 out:
224 if (tx_cpu >= 0)
225 atomic_inc(&per_cpu(siw_use_cnt, tx_cpu));
226 else
227 pr_warn("siw: no tx cpu found\n");
228
229 return tx_cpu;
230 }
231
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org