CC: [email protected] CC: [email protected] In-Reply-To: <[email protected]> References: <[email protected]> TO: Ravi Bangoria <[email protected]>
Hi Ravi, [FYI, it's a private test report for your RFC patch.] [auto build test WARNING on tip/perf/core] [also build test WARNING on powerpc/next tip/sched/core v5.16 next-20220114] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch] url: https://github.com/0day-ci/linux/commits/Ravi-Bangoria/perf-Rewrite-core-context-handling/20220113-215022 base: https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git a9f4a6e92b3b319296fb078da2615f618f6cd80c :::::: branch date: 32 hours ago :::::: commit date: 32 hours ago config: arm-randconfig-c002-20220113 (https://download.01.org/0day-ci/archive/20220115/[email protected]/config) compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project d1021978b8e7e35dcc30201ca1731d64b5a602a8) 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://github.com/0day-ci/linux/commit/f7cf7134e405062bf0f22c3ba5637241c4c4d06a git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Ravi-Bangoria/perf-Rewrite-core-context-handling/20220113-215022 git checkout f7cf7134e405062bf0f22c3ba5637241c4c4d06a # save the config file 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 <[email protected]> clang-analyzer warnings: (new ones prefixed by >>) ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ kernel/events/core.c:3752:2: note: Loop condition is true. Entering loop body while (event_heap.nr) { ^ kernel/events/core.c:3753:9: note: Calling 'merge_sched_in' ret = func(*evt, data); ^~~~~~~~~~~~~~~~ kernel/events/core.c:3792:35: note: Assuming pointer value is null struct perf_event_context *ctx = event->ctx; ^~~~~~~~~~ kernel/events/core.c:3795:6: note: Assuming field 'state' is > PERF_EVENT_STATE_OFF if (event->state <= PERF_EVENT_STATE_OFF) ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ kernel/events/core.c:3795:2: note: Taking false branch if (event->state <= PERF_EVENT_STATE_OFF) ^ kernel/events/core.c:3798:6: note: Assuming the condition is true if (!event_filter_match(event)) ^~~~~~~~~~~~~~~~~~~~~~~~~~ kernel/events/core.c:3798:2: note: Taking true branch if (!event_filter_match(event)) ^ kernel/events/core.c:3799:3: note: Returning zero, which participates in a condition later return 0; ^~~~~~~~ kernel/events/core.c:3753:9: note: Returning from 'merge_sched_in' ret = func(*evt, data); ^~~~~~~~~~~~~~~~ kernel/events/core.c:3754:7: note: 'ret' is 0 if (ret) ^~~ kernel/events/core.c:3754:3: note: Taking false branch if (ret) ^ kernel/events/core.c:3758:3: note: Taking false branch if (*evt) ^ kernel/events/core.c:3761:4: note: Calling 'min_heap_pop' min_heap_pop(&event_heap, &perf_min_heap); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ include/linux/min_heap.h:84:16: note: Assuming field 'nr' is > 0 if (WARN_ONCE(heap->nr <= 0, "Popping an empty heap")) ^ include/asm-generic/bug.h:150:18: note: expanded from macro 'WARN_ONCE' DO_ONCE_LITE_IF(condition, WARN, 1, format) ^~~~~~~~~ include/linux/once_lite.h:15:27: note: expanded from macro 'DO_ONCE_LITE_IF' bool __ret_do_once = !!(condition); \ ^~~~~~~~~ include/linux/min_heap.h:84:6: note: '__ret_do_once' is false if (WARN_ONCE(heap->nr <= 0, "Popping an empty heap")) ^ include/asm-generic/bug.h:150:2: note: expanded from macro 'WARN_ONCE' DO_ONCE_LITE_IF(condition, WARN, 1, format) ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ include/linux/once_lite.h:17:16: note: expanded from macro 'DO_ONCE_LITE_IF' if (unlikely(__ret_do_once && !__already_done)) { \ ^~~~~~~~~~~~~ include/linux/compiler.h:78:42: note: expanded from macro 'unlikely' # define unlikely(x) __builtin_expect(!!(x), 0) ^ include/linux/min_heap.h:84:6: note: Left side of '&&' is false if (WARN_ONCE(heap->nr <= 0, "Popping an empty heap")) ^ include/asm-generic/bug.h:150:2: note: expanded from macro 'WARN_ONCE' DO_ONCE_LITE_IF(condition, WARN, 1, format) ^ include/linux/once_lite.h:17:30: note: expanded from macro 'DO_ONCE_LITE_IF' if (unlikely(__ret_do_once && !__already_done)) { \ ^ include/linux/min_heap.h:84:6: note: Taking false branch if (WARN_ONCE(heap->nr <= 0, "Popping an empty heap")) ^ include/asm-generic/bug.h:150:2: note: expanded from macro 'WARN_ONCE' DO_ONCE_LITE_IF(condition, WARN, 1, format) ^ include/linux/once_lite.h:17:3: note: expanded from macro 'DO_ONCE_LITE_IF' if (unlikely(__ret_do_once && !__already_done)) { \ ^ include/linux/min_heap.h:84:2: note: Taking false branch if (WARN_ONCE(heap->nr <= 0, "Popping an empty heap")) ^ include/linux/min_heap.h:90:2: note: Value assigned to 'event_heap.nr', which participates in a condition later min_heapify(heap, 0, func); ^~~~~~~~~~~~~~~~~~~~~~~~~~ kernel/events/core.c:3761:4: note: Returning from 'min_heap_pop' min_heap_pop(&event_heap, &perf_min_heap); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ kernel/events/core.c:3752:2: note: Loop condition is true. Entering loop body while (event_heap.nr) { ^ kernel/events/core.c:3753:14: note: Passing null pointer value via 1st parameter 'event' ret = func(*evt, data); ^~~~ kernel/events/core.c:3753:9: note: Calling 'merge_sched_in' ret = func(*evt, data); ^~~~~~~~~~~~~~~~ kernel/events/core.c:3792:35: note: Access to field 'ctx' results in a dereference of a null pointer (loaded from variable 'event') struct perf_event_context *ctx = event->ctx; ^~~~~ >> kernel/events/core.c:4277:2: warning: Value stored to 'task_ctx' is never >> read [clang-analyzer-deadcode.DeadStores] task_ctx = cpuctx->task_ctx; ^ ~~~~~~~~~~~~~~~~ kernel/events/core.c:4277:2: note: Value stored to 'task_ctx' is never read task_ctx = cpuctx->task_ctx; ^ ~~~~~~~~~~~~~~~~ kernel/events/core.c:4777:2: warning: Value stored to 'err' is never read [clang-analyzer-deadcode.DeadStores] err = -EINVAL; ^ ~~~~~~~ kernel/events/core.c:4777:2: note: Value stored to 'err' is never read err = -EINVAL; ^ ~~~~~~~ kernel/events/core.c:10439:13: warning: Dereference of null pointer [clang-analyzer-core.NullDereference] for (vma = mm->mmap; vma; vma = vma->vm_next) { ^ kernel/events/core.c:10454:39: note: Calling 'perf_event_addr_filters' struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ include/linux/perf_event.h:1475:6: note: Assuming field 'parent' is null if (event->parent) ^~~~~~~~~~~~~ include/linux/perf_event.h:1475:2: note: Taking false branch if (event->parent) ^ include/linux/perf_event.h:1478:2: note: Returning without writing to 'event->addr_filters.nr_file_filters', which participates in a condition later return ifh; ^ kernel/events/core.c:10454:39: note: Returning from 'perf_event_addr_filters' struct perf_addr_filters_head *ifh = perf_event_addr_filters(event); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ kernel/events/core.c:10455:29: note: Left side of '||' is false struct task_struct *task = READ_ONCE(event->ctx->task); ^ include/asm-generic/rwonce.h:49:2: note: expanded from macro 'READ_ONCE' compiletime_assert_rwonce_type(x); \ ^ include/asm-generic/rwonce.h:36:21: note: expanded from macro 'compiletime_assert_rwonce_type' compiletime_assert(__native_word(t) || sizeof(t) == sizeof(long long), \ ^ include/linux/compiler_types.h:302:3: note: expanded from macro '__native_word' (sizeof(t) == sizeof(char) || sizeof(t) == sizeof(short) || \ ^ kernel/events/core.c:10455:29: note: Left side of '||' is false struct task_struct *task = READ_ONCE(event->ctx->task); ^ include/asm-generic/rwonce.h:49:2: note: expanded from macro 'READ_ONCE' compiletime_assert_rwonce_type(x); \ ^ include/asm-generic/rwonce.h:36:21: note: expanded from macro 'compiletime_assert_rwonce_type' compiletime_assert(__native_word(t) || sizeof(t) == sizeof(long long), \ ^ include/linux/compiler_types.h:302:3: note: expanded from macro '__native_word' (sizeof(t) == sizeof(char) || sizeof(t) == sizeof(short) || \ ^ kernel/events/core.c:10455:29: note: Left side of '||' is true struct task_struct *task = READ_ONCE(event->ctx->task); ^ include/asm-generic/rwonce.h:49:2: note: expanded from macro 'READ_ONCE' compiletime_assert_rwonce_type(x); \ ^ include/asm-generic/rwonce.h:36:21: note: expanded from macro 'compiletime_assert_rwonce_type' compiletime_assert(__native_word(t) || sizeof(t) == sizeof(long long), \ ^ include/linux/compiler_types.h:303:28: note: expanded from macro '__native_word' sizeof(t) == sizeof(int) || sizeof(t) == sizeof(long)) ^ kernel/events/core.c:10455:29: note: Taking false branch struct task_struct *task = READ_ONCE(event->ctx->task); ^ include/asm-generic/rwonce.h:49:2: note: expanded from macro 'READ_ONCE' compiletime_assert_rwonce_type(x); \ ^ include/asm-generic/rwonce.h:36:2: note: expanded from macro 'compiletime_assert_rwonce_type' compiletime_assert(__native_word(t) || sizeof(t) == sizeof(long long), \ ^ include/linux/compiler_types.h:335:2: note: expanded from macro 'compiletime_assert' _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) ^ include/linux/compiler_types.h:323:2: note: expanded from macro '_compiletime_assert' __compiletime_assert(condition, msg, prefix, suffix) ^ include/linux/compiler_types.h:315:3: note: expanded from macro '__compiletime_assert' if (!(condition)) \ ^ kernel/events/core.c:10455:29: note: Loop condition is false. Exiting loop struct task_struct *task = READ_ONCE(event->ctx->task); ^ include/asm-generic/rwonce.h:49:2: note: expanded from macro 'READ_ONCE' compiletime_assert_rwonce_type(x); \ ^ include/asm-generic/rwonce.h:36:2: note: expanded from macro 'compiletime_assert_rwonce_type' compiletime_assert(__native_word(t) || sizeof(t) == sizeof(long long), \ ^ include/linux/compiler_types.h:335:2: note: expanded from macro 'compiletime_assert' _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) ^ include/linux/compiler_types.h:323:2: note: expanded from macro '_compiletime_assert' __compiletime_assert(condition, msg, prefix, suffix) ^ include/linux/compiler_types.h:307:2: note: expanded from macro '__compiletime_assert' do { \ vim +/task_ctx +4277 kernel/events/core.c 8d5bce0c37fa10 kernel/events/core.c Peter Zijlstra 2018-03-09 4257 f7cf7134e40506 kernel/events/core.c Peter Zijlstra 2022-01-13 4258 static bool perf_rotate_context(struct perf_cpu_pmu_context *cpc) 8d5bce0c37fa10 kernel/events/core.c Peter Zijlstra 2018-03-09 4259 { f7cf7134e40506 kernel/events/core.c Peter Zijlstra 2022-01-13 4260 struct perf_cpu_context *cpuctx = this_cpu_ptr(&cpu_context); f7cf7134e40506 kernel/events/core.c Peter Zijlstra 2022-01-13 4261 struct perf_event_pmu_context *cpu_epc, *task_epc = NULL; 8d5bce0c37fa10 kernel/events/core.c Peter Zijlstra 2018-03-09 4262 struct perf_event *cpu_event = NULL, *task_event = NULL; fd7d55172d1e2e kernel/events/core.c Ian Rogers 2019-06-01 4263 struct perf_event_context *task_ctx = NULL; fd7d55172d1e2e kernel/events/core.c Ian Rogers 2019-06-01 4264 int cpu_rotate, task_rotate; f7cf7134e40506 kernel/events/core.c Peter Zijlstra 2022-01-13 4265 struct pmu *pmu; 8d5bce0c37fa10 kernel/events/core.c Peter Zijlstra 2018-03-09 4266 8d5bce0c37fa10 kernel/events/core.c Peter Zijlstra 2018-03-09 4267 /* 8d5bce0c37fa10 kernel/events/core.c Peter Zijlstra 2018-03-09 4268 * Since we run this from IRQ context, nobody can install new 8d5bce0c37fa10 kernel/events/core.c Peter Zijlstra 2018-03-09 4269 * events, thus the event count values are stable. 8d5bce0c37fa10 kernel/events/core.c Peter Zijlstra 2018-03-09 4270 */ 7fc23a53807970 kernel/perf_counter.c Peter Zijlstra 2009-05-08 4271 f7cf7134e40506 kernel/events/core.c Peter Zijlstra 2022-01-13 4272 cpu_epc = &cpc->epc; f7cf7134e40506 kernel/events/core.c Peter Zijlstra 2022-01-13 4273 pmu = cpu_epc->pmu; f7cf7134e40506 kernel/events/core.c Peter Zijlstra 2022-01-13 4274 task_epc = cpc->task_epc; f7cf7134e40506 kernel/events/core.c Peter Zijlstra 2022-01-13 4275 f7cf7134e40506 kernel/events/core.c Peter Zijlstra 2022-01-13 4276 cpu_rotate = cpu_epc->rotate_necessary; fd7d55172d1e2e kernel/events/core.c Ian Rogers 2019-06-01 @4277 task_ctx = cpuctx->task_ctx; f7cf7134e40506 kernel/events/core.c Peter Zijlstra 2022-01-13 4278 task_rotate = task_epc ? task_epc->rotate_necessary : 0; 9717e6cd3db22e kernel/perf_event.c Peter Zijlstra 2010-01-28 4279 8d5bce0c37fa10 kernel/events/core.c Peter Zijlstra 2018-03-09 4280 if (!(cpu_rotate || task_rotate)) 8d5bce0c37fa10 kernel/events/core.c Peter Zijlstra 2018-03-09 4281 return false; 0f5a2601284237 kernel/events/core.c Peter Zijlstra 2011-11-16 4282 facc43071cc0d4 kernel/events/core.c Peter Zijlstra 2011-04-09 4283 perf_ctx_lock(cpuctx, cpuctx->task_ctx); f7cf7134e40506 kernel/events/core.c Peter Zijlstra 2022-01-13 4284 perf_pmu_disable(pmu); 0f5a2601284237 kernel/events/core.c Peter Zijlstra 2011-11-16 4285 8d5bce0c37fa10 kernel/events/core.c Peter Zijlstra 2018-03-09 4286 if (task_rotate) f7cf7134e40506 kernel/events/core.c Peter Zijlstra 2022-01-13 4287 task_event = ctx_event_to_rotate(task_epc); 8d5bce0c37fa10 kernel/events/core.c Peter Zijlstra 2018-03-09 4288 if (cpu_rotate) f7cf7134e40506 kernel/events/core.c Peter Zijlstra 2022-01-13 4289 cpu_event = ctx_event_to_rotate(cpu_epc); 8703a7cfe148f7 kernel/events/core.c Peter Zijlstra 2017-11-13 4290 8d5bce0c37fa10 kernel/events/core.c Peter Zijlstra 2018-03-09 4291 /* 8d5bce0c37fa10 kernel/events/core.c Peter Zijlstra 2018-03-09 4292 * As per the order given at ctx_resched() first 'pop' task flexible 8d5bce0c37fa10 kernel/events/core.c Peter Zijlstra 2018-03-09 4293 * and then, if needed CPU flexible. 8d5bce0c37fa10 kernel/events/core.c Peter Zijlstra 2018-03-09 4294 */ f7cf7134e40506 kernel/events/core.c Peter Zijlstra 2022-01-13 4295 if (task_event || (task_epc && cpu_event)) { f7cf7134e40506 kernel/events/core.c Peter Zijlstra 2022-01-13 4296 update_context_time(task_epc->ctx); f7cf7134e40506 kernel/events/core.c Peter Zijlstra 2022-01-13 4297 __pmu_ctx_sched_out(task_epc, EVENT_FLEXIBLE); f7cf7134e40506 kernel/events/core.c Peter Zijlstra 2022-01-13 4298 } 235c7fc7c500e4 kernel/perf_counter.c Ingo Molnar 2008-12-21 4299 f7cf7134e40506 kernel/events/core.c Peter Zijlstra 2022-01-13 4300 if (cpu_event) { f7cf7134e40506 kernel/events/core.c Peter Zijlstra 2022-01-13 4301 update_context_time(&cpuctx->ctx); f7cf7134e40506 kernel/events/core.c Peter Zijlstra 2022-01-13 4302 __pmu_ctx_sched_out(cpu_epc, EVENT_FLEXIBLE); 8d5bce0c37fa10 kernel/events/core.c Peter Zijlstra 2018-03-09 4303 rotate_ctx(&cpuctx->ctx, cpu_event); f7cf7134e40506 kernel/events/core.c Peter Zijlstra 2022-01-13 4304 __pmu_ctx_sched_in(&cpuctx->ctx, pmu); f7cf7134e40506 kernel/events/core.c Peter Zijlstra 2022-01-13 4305 } 0793a61d4df8da kernel/perf_counter.c Thomas Gleixner 2008-12-04 4306 f7cf7134e40506 kernel/events/core.c Peter Zijlstra 2022-01-13 4307 if (task_event) f7cf7134e40506 kernel/events/core.c Peter Zijlstra 2022-01-13 4308 rotate_ctx(task_epc->ctx, task_event); 0f5a2601284237 kernel/events/core.c Peter Zijlstra 2011-11-16 4309 f7cf7134e40506 kernel/events/core.c Peter Zijlstra 2022-01-13 4310 if (task_event || (task_epc && cpu_event)) f7cf7134e40506 kernel/events/core.c Peter Zijlstra 2022-01-13 4311 __pmu_ctx_sched_in(task_epc->ctx, pmu); f7cf7134e40506 kernel/events/core.c Peter Zijlstra 2022-01-13 4312 f7cf7134e40506 kernel/events/core.c Peter Zijlstra 2022-01-13 4313 perf_pmu_enable(pmu); 0f5a2601284237 kernel/events/core.c Peter Zijlstra 2011-11-16 4314 perf_ctx_unlock(cpuctx, cpuctx->task_ctx); 9e6302056f8029 kernel/events/core.c Stephane Eranian 2013-04-03 4315 8d5bce0c37fa10 kernel/events/core.c Peter Zijlstra 2018-03-09 4316 return true; e9d2b064149ff7 kernel/perf_event.c Peter Zijlstra 2010-09-17 4317 } e9d2b064149ff7 kernel/perf_event.c Peter Zijlstra 2010-09-17 4318 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/[email protected] _______________________________________________ kbuild mailing list -- [email protected] To unsubscribe send an email to [email protected]
