Re: [linux-next:master 8440/9522] drivers/cpufreq/qcom-cpufreq-hw.c:294:3: warning: Value stored to 'opp' is never read [clang-analyzer-deadcode.DeadStores]
From: Chen, Rong A <hidden>
Date: 2021-08-24 06:53:38
Also in:
oe-kbuild-all
On 8/23/2021 2:52 PM, Viresh Kumar wrote:
On 22-08-21, 19:41, kernel test robot wrote:quoted
tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master head: 86ed57fd8c93fdfaabb4f58e78455180fa7d8a84 commit: 86afc1df661a99dcd6b8d264cae171f1ead2b7b8 [8440/9522] cpufreq: qcom-cpufreq-hw: Add dcvs interrupt support config: arm-randconfig-c002-20210822 (attached as .config) compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project a83d99c55ebb14532c414066a5aa3bdb65389965) 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 # install arm cross compiling tool for clang build # apt-get install binutils-arm-linux-gnueabi # https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=86afc1df661a99dcd6b8d264cae171f1ead2b7b8 git remote add linux-next https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git git fetch --no-tags linux-next master git checkout 86afc1df661a99dcd6b8d264cae171f1ead2b7b8 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm clang-analyzer If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <redacted>This doesn't look right, it says issues are with cpufreq-hw driver but points at hid-core ?
Hi Viresh, The warning with the prefix ">>" is pointed to this commit, others are only for reference. Best Regards, Rong Chen
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clang-analyzer warnings: (new ones prefixed by >>)
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drivers/cpufreq/qcom-cpufreq-hw.c:294:3: warning: Value stored to 'opp' is never read [clang-analyzer-deadcode.DeadStores]opp = dev_pm_opp_find_freq_ceil(dev, &freq_hz); ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/cpufreq/qcom-cpufreq-hw.c:294:3: note: Value stored to 'opp' is never read opp = dev_pm_opp_find_freq_ceil(dev, &freq_hz); ^ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 7 warnings generated. Suppressed 7 warnings (7 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 3 warnings generated. Suppressed 3 warnings (3 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 3 warnings generated. Suppressed 3 warnings (3 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 3 warnings generated. Suppressed 3 warnings (3 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 3 warnings generated. Suppressed 3 warnings (3 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 6 warnings generated. Suppressed 6 warnings (6 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 2 warnings generated. Suppressed 2 warnings (2 in non-user code). Use -header-filter=.* to display errors from all non-system headers. Use -system-headers to display errors from system headers as well. 7 warnings generated. drivers/dma/xgene-dma.c:445:36: warning: The result of the left shift is undefined due to shifting by '32', which is greater or equal to the width of type 'int' [clang-analyzer-core.UndefinedBinaryOperatorResult] desc1->m2 |= cpu_to_le64((scf[i] << ((i + 1) * 8))); ^ include/linux/byteorder/generic.h:86:21: note: expanded from macro 'cpu_to_le64' #define cpu_to_le64 __cpu_to_le64 ^ drivers/dma/xgene-dma.c:895:15: note: Assuming 'dchan' is non-null if (unlikely(!dchan || !len)) ^ include/linux/compiler.h:78:42: note: expanded from macro 'unlikely' # define unlikely(x) __builtin_expect(!!(x), 0) ^ drivers/dma/xgene-dma.c:895:15: note: Left side of '||' is false if (unlikely(!dchan || !len)) ^ drivers/dma/xgene-dma.c:895:25: note: Assuming 'len' is not equal to 0 if (unlikely(!dchan || !len)) ^ include/linux/compiler.h:78:42: note: expanded from macro 'unlikely' # define unlikely(x) __builtin_expect(!!(x), 0) ^ drivers/dma/xgene-dma.c:895:2: note: Taking false branch if (unlikely(!dchan || !len)) ^ drivers/dma/xgene-dma.c:898:9: note: Left side of '&&' is false chan = to_dma_chan(dchan); ^ drivers/dma/xgene-dma.c:191:2: note: expanded from macro 'to_dma_chan' container_of(dchan, struct xgene_dma_chan, dma_chan) ^ include/linux/kernel.h:495:61: note: expanded from macro 'container_of' BUILD_BUG_ON_MSG(!__same_type(*(ptr), ((type *)0)->member) && \ ^ drivers/dma/xgene-dma.c:898:9: note: Taking false branch chan = to_dma_chan(dchan); ^ drivers/dma/xgene-dma.c:191:2: note: expanded from macro 'to_dma_chan' container_of(dchan, struct xgene_dma_chan, dma_chan) ^ include/linux/kernel.h:495:2: note: expanded from macro 'container_of' BUILD_BUG_ON_MSG(!__same_type(*(ptr), ((type *)0)->member) && \ ^ include/linux/build_bug.h:39:37: note: expanded from macro 'BUILD_BUG_ON_MSG' #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg) ^ include/linux/compiler_types.h:328:2: note: expanded from macro 'compiletime_assert' _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) ^ include/linux/compiler_types.h:316:2: note: expanded from macro '_compiletime_assert' __compiletime_assert(condition, msg, prefix, suffix) ^ include/linux/compiler_types.h:308:3: note: expanded from macro '__compiletime_assert' if (!(condition)) \ vim +/opp +294 drivers/cpufreq/qcom-cpufreq-hw.c 275 276 static void qcom_lmh_dcvs_notify(struct qcom_cpufreq_data *data) 277 { 278 unsigned long max_capacity, capacity, freq_hz, throttled_freq; 279 struct cpufreq_policy *policy = data->policy; 280 int cpu = cpumask_first(policy->cpus); 281 struct device *dev = get_cpu_device(cpu); 282 struct dev_pm_opp *opp; 283 unsigned int freq; 284 285 /* 286 * Get the h/w throttled frequency, normalize it using the 287 * registered opp table and use it to calculate thermal pressure. 288 */ 289 freq = qcom_lmh_get_throttle_freq(data); 290 freq_hz = freq * HZ_PER_KHZ; 291 292 opp = dev_pm_opp_find_freq_floor(dev, &freq_hz); 293 if (IS_ERR(opp) && PTR_ERR(opp) == -ERANGE) > 294 opp = dev_pm_opp_find_freq_ceil(dev, &freq_hz); 295 296 throttled_freq = freq_hz / HZ_PER_KHZ; 297 298 /* Update thermal pressure */ 299 300 max_capacity = arch_scale_cpu_capacity(cpu); 301 capacity = mult_frac(max_capacity, throttled_freq, policy->cpuinfo.max_freq); 302 303 /* Don't pass boost capacity to scheduler */ 304 if (capacity > max_capacity) 305 capacity = max_capacity; 306 307 arch_set_thermal_pressure(policy->cpus, max_capacity - capacity); 308 309 /* 310 * In the unlikely case policy is unregistered do not enable 311 * polling or h/w interrupt 312 */ 313 mutex_lock(&data->throttle_lock); 314 if (data->cancel_throttle) 315 goto out; 316 317 /* 318 * If h/w throttled frequency is higher than what cpufreq has requested 319 * for, then stop polling and switch back to interrupt mechanism. 320 */ 321 if (throttled_freq >= qcom_cpufreq_hw_get(cpu)) 322 enable_irq(data->throttle_irq); 323 else 324 mod_delayed_work(system_highpri_wq, &data->throttle_work, 325 msecs_to_jiffies(10)); 326 327 out: 328 mutex_unlock(&data->throttle_lock); 329 } 330 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org