From: kernel test robot <lkp@intel.com>
To: James Morse <james.morse@arm.com>
Cc: llvm@lists.linux.dev, oe-kbuild-all@lists.linux.dev
Subject: [morse:mpam/snapshot/v6.17-rc4 68/88] drivers/resctrl/mpam_resctrl.c:416:14: warning: result of comparison of constant 65536 with expression of type 'u16' (aka 'unsigned short') is always false
Date: Fri, 12 Sep 2025 18:57:25 +0800 [thread overview]
Message-ID: <202509121830.gMaSfEnY-lkp@intel.com> (raw)
Hi James,
First bad commit (maybe != root cause):
tree: https://git.kernel.org/pub/scm/linux/kernel/git/morse/linux.git mpam/snapshot/v6.17-rc4
head: 1e5b9e907a3fa515c3745ed2969a1f285dcc03d2
commit: ee1ef14f8f760bcf104788390161f092691a366a [68/88] arm64: mpam: Select ARCH_HAS_CPU_RESCTRL
config: arm64-allmodconfig (https://download.01.org/0day-ci/archive/20250912/202509121830.gMaSfEnY-lkp@intel.com/config)
compiler: clang version 19.1.7 (https://github.com/llvm/llvm-project cd708029e0b2869e80abe31ddb175f7c35361f90)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250912/202509121830.gMaSfEnY-lkp@intel.com/reproduce)
If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202509121830.gMaSfEnY-lkp@intel.com/
All warnings (new ones prefixed by >>):
>> drivers/resctrl/mpam_resctrl.c:416:14: warning: result of comparison of constant 65536 with expression of type 'u16' (aka 'unsigned short') is always false [-Wtautological-constant-out-of-range-compare]
416 | if (cfg.mon == USE_RMID_IDX) {
| ~~~~~~~ ^ ~~~~~~~~~~~~
drivers/resctrl/mpam_resctrl.c:419:15: warning: result of comparison of constant -1 with expression of type 'u16' (aka 'unsigned short') is always false [-Wtautological-constant-out-of-range-compare]
419 | if (cfg.mon == -1)
| ~~~~~~~ ^ ~~
drivers/resctrl/mpam_resctrl.c:467:14: warning: result of comparison of constant -1 with expression of type 'u16' (aka 'unsigned short') is always false [-Wtautological-constant-out-of-range-compare]
467 | if (cfg.mon == -1)
| ~~~~~~~ ^ ~~
3 warnings generated.
vim +416 drivers/resctrl/mpam_resctrl.c
08ea0634012302 James Morse 2023-03-09 380
6a2be13d0ae78b James Morse 2021-06-25 381 int resctrl_arch_rmid_read(struct rdt_resource *r, struct rdt_mon_domain *d,
6a2be13d0ae78b James Morse 2021-06-25 382 u32 closid, u32 rmid, enum resctrl_event_id eventid,
6a2be13d0ae78b James Morse 2021-06-25 383 u64 *val, void *arch_mon_ctx)
6a2be13d0ae78b James Morse 2021-06-25 384 {
6a2be13d0ae78b James Morse 2021-06-25 385 int err;
6a2be13d0ae78b James Morse 2021-06-25 386 u64 cdp_val;
6a2be13d0ae78b James Morse 2021-06-25 387 struct mon_cfg cfg;
6a2be13d0ae78b James Morse 2021-06-25 388 enum mpam_device_features type;
6a2be13d0ae78b James Morse 2021-06-25 389 struct mpam_resctrl_dom *l3_dom;
6a2be13d0ae78b James Morse 2021-06-25 390 struct mpam_component *mon_comp;
6a2be13d0ae78b James Morse 2021-06-25 391 u32 mon_idx = *(u32 *)arch_mon_ctx;
6a2be13d0ae78b James Morse 2021-06-25 392 struct mpam_resctrl_mon *mon = &mpam_resctrl_counters[eventid];
6a2be13d0ae78b James Morse 2021-06-25 393
6a2be13d0ae78b James Morse 2021-06-25 394 resctrl_arch_rmid_read_context_check();
6a2be13d0ae78b James Morse 2021-06-25 395
6a2be13d0ae78b James Morse 2021-06-25 396 if (!mon->class)
6a2be13d0ae78b James Morse 2021-06-25 397 return -EINVAL;
6a2be13d0ae78b James Morse 2021-06-25 398
6a2be13d0ae78b James Morse 2021-06-25 399 l3_dom = container_of(d, struct mpam_resctrl_dom, resctrl_mon_dom);
6a2be13d0ae78b James Morse 2021-06-25 400 mon_comp = l3_dom->mon_comp[eventid];
6a2be13d0ae78b James Morse 2021-06-25 401
6a2be13d0ae78b James Morse 2021-06-25 402 switch (eventid) {
6a2be13d0ae78b James Morse 2021-06-25 403 case QOS_L3_OCCUP_EVENT_ID:
6a2be13d0ae78b James Morse 2021-06-25 404 type = mpam_feat_msmon_csu;
6a2be13d0ae78b James Morse 2021-06-25 405 break;
6a2be13d0ae78b James Morse 2021-06-25 406 case QOS_L3_MBM_LOCAL_EVENT_ID:
6a2be13d0ae78b James Morse 2021-06-25 407 case QOS_L3_MBM_TOTAL_EVENT_ID:
6a2be13d0ae78b James Morse 2021-06-25 408 type = mpam_feat_msmon_mbwu;
6a2be13d0ae78b James Morse 2021-06-25 409 break;
6a2be13d0ae78b James Morse 2021-06-25 410 default:
6a2be13d0ae78b James Morse 2021-06-25 411 case QOS_NUM_EVENTS:
6a2be13d0ae78b James Morse 2021-06-25 412 return -EINVAL;
6a2be13d0ae78b James Morse 2021-06-25 413 }
6a2be13d0ae78b James Morse 2021-06-25 414
6a2be13d0ae78b James Morse 2021-06-25 415 cfg.mon = mon_idx;
6a2be13d0ae78b James Morse 2021-06-25 @416 if (cfg.mon == USE_RMID_IDX) {
6a2be13d0ae78b James Morse 2021-06-25 417 cfg.mon = resctrl_arch_rmid_idx_encode(closid, rmid);
6a2be13d0ae78b James Morse 2021-06-25 418 cfg.mon = mon->mbwu_idx_to_mon[cfg.mon];
6a2be13d0ae78b James Morse 2021-06-25 419 if (cfg.mon == -1)
6a2be13d0ae78b James Morse 2021-06-25 420 return -EINVAL;
6a2be13d0ae78b James Morse 2021-06-25 421 }
6a2be13d0ae78b James Morse 2021-06-25 422
6a2be13d0ae78b James Morse 2021-06-25 423 cfg.match_pmg = true;
6a2be13d0ae78b James Morse 2021-06-25 424 cfg.pmg = rmid;
08ea0634012302 James Morse 2023-03-09 425 cfg.opts = resctrl_evt_config_to_mpam(l3_dom->mbm_local_evt_cfg);
6a2be13d0ae78b James Morse 2021-06-25 426
6a2be13d0ae78b James Morse 2021-06-25 427 if (irqs_disabled()) {
6a2be13d0ae78b James Morse 2021-06-25 428 /* Check if we can access this domain without an IPI */
6a2be13d0ae78b James Morse 2021-06-25 429 err = -EIO;
6a2be13d0ae78b James Morse 2021-06-25 430 } else {
6a2be13d0ae78b James Morse 2021-06-25 431 if (cdp_enabled) {
6a2be13d0ae78b James Morse 2021-06-25 432 cfg.partid = closid << 1;
6a2be13d0ae78b James Morse 2021-06-25 433 err = mpam_msmon_read(mon_comp, &cfg, type, val);
6a2be13d0ae78b James Morse 2021-06-25 434 if (err)
6a2be13d0ae78b James Morse 2021-06-25 435 return err;
6a2be13d0ae78b James Morse 2021-06-25 436
6a2be13d0ae78b James Morse 2021-06-25 437 cfg.partid += 1;
6a2be13d0ae78b James Morse 2021-06-25 438 err = mpam_msmon_read(mon_comp, &cfg, type, &cdp_val);
6a2be13d0ae78b James Morse 2021-06-25 439 if (!err)
6a2be13d0ae78b James Morse 2021-06-25 440 *val += cdp_val;
6a2be13d0ae78b James Morse 2021-06-25 441 } else {
6a2be13d0ae78b James Morse 2021-06-25 442 cfg.partid = closid;
6a2be13d0ae78b James Morse 2021-06-25 443 err = mpam_msmon_read(mon_comp, &cfg, type, val);
6a2be13d0ae78b James Morse 2021-06-25 444 }
6a2be13d0ae78b James Morse 2021-06-25 445 }
6a2be13d0ae78b James Morse 2021-06-25 446
6a2be13d0ae78b James Morse 2021-06-25 447 return err;
6a2be13d0ae78b James Morse 2021-06-25 448 }
6a2be13d0ae78b James Morse 2021-06-25 449
:::::: The code at line 416 was first introduced by commit
:::::: 6a2be13d0ae78b4cc1506f94ea595b043bfab548 arm_mpam: resctrl: Add resctrl_arch_rmid_read() and resctrl_arch_reset_rmid()
:::::: TO: James Morse <james.morse@arm.com>
:::::: CC: James Morse <james.morse@arm.com>
--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki
reply other threads:[~2025-09-12 10:57 UTC|newest]
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