kernel/linux.git/tools, branch v4.19.156

tools: perf: Fix build error in v4.19.y

2020-11-10T11:36:02+00:00

perf may fail to build in v4.19.y with the following error. util/evsel.c: In function ‘perf_evsel__exit’: util/util.h:25:28: error: passing argument 1 of ‘free’ discards ‘const’ qualifier from pointer target type This is observed (at least) with gcc v6.5.0. The underlying problem is the following statement. zfree(&evsel->pmu_name); evsel->pmu_name is decared 'const *'. zfree in turn is defined as #define zfree(ptr) ({ free(*ptr); *ptr = NULL; }) and thus passes the const * to free(). The problem is not seen in the upstream kernel since zfree() has been rewritten there. The problem has been introduced into v4.19.y with the backport of upstream commit d4953f7ef1a2 (perf parse-events: Fix 3 use after frees found with clang ASAN). One possible fix of this problem would be to not declare pmu_name as const. This patch chooses to typecast the parameter of zfree() to void *, following the guidance from the upstream kernel which does the same since commit 7f7c536f23e6a ("tools lib: Adopt zalloc()/zfree() from tools/perf") Fixes: a0100a363098 ("perf parse-events: Fix 3 use after frees found with clang ASAN") Signed-off-by: Guenter Roeck Signed-off-by: Greg Kroah-Hartman

perf python scripting: Fix printable strings in python3 scripts

2020-11-05T10:08:52+00:00

commit 6fcd5ddc3b1467b3586972ef785d0d926ae4cdf4 upstream. Hagen reported broken strings in python3 tracepoint scripts: make PYTHON=python3 perf record -e sched:sched_switch -a -- sleep 5 perf script --gen-script py perf script -s ./perf-script.py [..] sched__sched_switch 7 563231.759525792 0 swapper prev_comm=bytearray(b'swapper/7\x00\x00\x00\x00\x00\x00\x00'), prev_pid=0, prev_prio=120, prev_state=, next_comm=bytearray(b'mutex-thread-co\x00'), The problem is in the is_printable_array function that does not take the zero byte into account and claim such string as not printable, so the code will create byte array instead of string. Committer testing: After this fix: sched__sched_switch 3 484522.497072626 1158680 kworker/3:0-eve prev_comm=kworker/3:0, prev_pid=1158680, prev_prio=120, prev_state=I, next_comm=swapper/3, next_pid=0, next_prio=120 Sample: {addr=0, cpu=3, datasrc=84410401, datasrc_decode=N/A|SNP N/A|TLB N/A|LCK N/A, ip=18446744071841817196, period=1, phys_addr=0, pid=1158680, tid=1158680, time=484522497072626, transaction=0, values=[(0, 0)], weight=0} sched__sched_switch 4 484522.497085610 1225814 perf prev_comm=perf, prev_pid=1225814, prev_prio=120, prev_state=, next_comm=migration/4, next_pid=30, next_prio=0 Sample: {addr=0, cpu=4, datasrc=84410401, datasrc_decode=N/A|SNP N/A|TLB N/A|LCK N/A, ip=18446744071841817196, period=1, phys_addr=0, pid=1225814, tid=1225814, time=484522497085610, transaction=0, values=[(0, 0)], weight=0} Fixes: 249de6e07458 ("perf script python: Fix string vs byte array resolving") Signed-off-by: Jiri Olsa Tested-by: Arnaldo Carvalho de Melo Tested-by: Hagen Paul Pfeifer Cc: Alexander Shishkin Cc: Mark Rutland Cc: Michael Petlan Cc: Namhyung Kim Cc: Peter Zijlstra Cc: stable@vger.kernel.org Link: http://lore.kernel.org/lkml/20200928201135.3633850-1-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Greg Kroah-Hartman

bpf: Fix comment for helper bpf_current_task_under_cgroup()

2020-11-05T10:08:34+00:00

commit 1aef5b4391f0c75c0a1523706a7b0311846ee12f upstream. This should be "current" not "skb". Fixes: c6b5fb8690fa ("bpf: add documentation for eBPF helpers (42-50)") Signed-off-by: Song Liu Signed-off-by: Alexei Starovoitov Cc: Link: https://lore.kernel.org/bpf/20200910203314.70018-1-songliubraving@fb.com Signed-off-by: Greg Kroah-Hartman

objtool: Support Clang non-section symbols in ORC generation

2020-11-05T10:08:31+00:00

commit e81e0724432542af8d8c702c31e9d82f57b1ff31 upstream. When compiling the kernel with AS=clang, objtool produces a lot of warnings: warning: objtool: missing symbol for section .text warning: objtool: missing symbol for section .init.text warning: objtool: missing symbol for section .ref.text It then fails to generate the ORC table. The problem is that objtool assumes text section symbols always exist. But the Clang assembler is aggressive about removing them. When generating relocations for the ORC table, objtool always tries to reference instructions by their section symbol offset. If the section symbol doesn't exist, it bails. Do a fallback: when a section symbol isn't available, reference a function symbol instead. Reported-by: Dmitry Golovin Signed-off-by: Josh Poimboeuf Signed-off-by: Borislav Petkov Tested-by: Nathan Chancellor Reviewed-by: Miroslav Benes Acked-by: Peter Zijlstra (Intel) Link: https://github.com/ClangBuiltLinux/linux/issues/669 Link: https://lkml.kernel.org/r/9a9cae7fcf628843aabe5a086b1a3c5bf50f42e8.1585761021.git.jpoimboe@redhat.com Cc: Nick Desaulniers Signed-off-by: Greg Kroah-Hartman

perf intel-pt: Fix "context_switch event has no tid" error

2020-10-30T09:38:19+00:00

[ Upstream commit 7d537a8d2e76bc4fc71e34545ceaa463ac2cd928 ] A context_switch event can have no tid because pids can be detached from a task while the task is still running (in do_exit()). Note this won't happen with per-task contexts because then tracing stops at perf_event_exit_task() If a task with no tid gets preempted, or a dying task gets preempted and its parent releases it, when it subsequently gets switched back in, Intel PT will not be able to determine what task is running and prints an error "context_switch event has no tid". However, it is not really an error because the task is in kernel space and the decoder can continue to decode successfully. Fix by changing the error to be only a logged message, and make allowance for tid == -1. Example: Using 5.9-rc4 with Preemptible Kernel (Low-Latency Desktop) e.g. $ uname -r 5.9.0-rc4 $ grep PREEMPT .config # CONFIG_PREEMPT_NONE is not set # CONFIG_PREEMPT_VOLUNTARY is not set CONFIG_PREEMPT=y CONFIG_PREEMPT_COUNT=y CONFIG_PREEMPTION=y CONFIG_PREEMPT_RCU=y CONFIG_PREEMPT_NOTIFIERS=y CONFIG_DRM_I915_PREEMPT_TIMEOUT=640 CONFIG_DEBUG_PREEMPT=y # CONFIG_PREEMPT_TRACER is not set # CONFIG_PREEMPTIRQ_DELAY_TEST is not set Before: $ cat forkit.c #include #include #include int main() { pid_t child; int status = 0; child = fork(); if (child == 0) return 123; wait(&status); return 0; } $ gcc -o forkit forkit.c $ sudo ~/bin/perf record --kcore -a -m,64M -e intel_pt/cyc/k & [1] 11016 $ taskset 2 ./forkit $ sudo pkill perf $ [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 17.262 MB perf.data ] [1]+ Terminated sudo ~/bin/perf record --kcore -a -m,64M -e intel_pt/cyc/k $ sudo ~/bin/perf script --show-task-events --show-switch-events --itrace=iqqe-o -C 1 --ns | grep -C 2 forkit context_switch event has no tid taskset 11019 [001] 66663.270045029: 1 instructions:k: ffffffffb1d9f844 strnlen_user+0xb4 ([kernel.kallsyms]) taskset 11019 [001] 66663.270201816: 1 instructions:k: ffffffffb1a83121 unmap_page_range+0x561 ([kernel.kallsyms]) forkit 11019 [001] 66663.270327553: PERF_RECORD_COMM exec: forkit:11019/11019 forkit 11019 [001] 66663.270420028: 1 instructions:k: ffffffffb1db9537 __clear_user+0x27 ([kernel.kallsyms]) forkit 11019 [001] 66663.270648704: 1 instructions:k: ffffffffb18829e6 do_user_addr_fault+0xf6 ([kernel.kallsyms]) forkit 11019 [001] 66663.270833163: 1 instructions:k: ffffffffb230a825 irqentry_exit_to_user_mode+0x15 ([kernel.kallsyms]) forkit 11019 [001] 66663.271092359: 1 instructions:k: ffffffffb1aea3d9 lock_page_memcg+0x9 ([kernel.kallsyms]) forkit 11019 [001] 66663.271207092: PERF_RECORD_FORK(11020:11020):(11019:11019) forkit 11019 [001] 66663.271234775: PERF_RECORD_SWITCH_CPU_WIDE OUT next pid/tid: 11020/11020 forkit 11020 [001] 66663.271238407: PERF_RECORD_SWITCH_CPU_WIDE IN prev pid/tid: 11019/11019 forkit 11020 [001] 66663.271312066: 1 instructions:k: ffffffffb1a88140 handle_mm_fault+0x10 ([kernel.kallsyms]) forkit 11020 [001] 66663.271476225: PERF_RECORD_EXIT(11020:11020):(11019:11019) forkit 11020 [001] 66663.271497488: PERF_RECORD_SWITCH_CPU_WIDE OUT preempt next pid/tid: 11019/11019 forkit 11019 [001] 66663.271500523: PERF_RECORD_SWITCH_CPU_WIDE IN prev pid/tid: 11020/11020 forkit 11019 [001] 66663.271517241: 1 instructions:k: ffffffffb24012cd error_entry+0x6d ([kernel.kallsyms]) forkit 11019 [001] 66663.271664080: PERF_RECORD_EXIT(11019:11019):(1386:1386) After: $ sudo ~/bin/perf script --show-task-events --show-switch-events --itrace=iqqe-o -C 1 --ns | grep -C 2 forkit taskset 11019 [001] 66663.270045029: 1 instructions:k: ffffffffb1d9f844 strnlen_user+0xb4 ([kernel.kallsyms]) taskset 11019 [001] 66663.270201816: 1 instructions:k: ffffffffb1a83121 unmap_page_range+0x561 ([kernel.kallsyms]) forkit 11019 [001] 66663.270327553: PERF_RECORD_COMM exec: forkit:11019/11019 forkit 11019 [001] 66663.270420028: 1 instructions:k: ffffffffb1db9537 __clear_user+0x27 ([kernel.kallsyms]) forkit 11019 [001] 66663.270648704: 1 instructions:k: ffffffffb18829e6 do_user_addr_fault+0xf6 ([kernel.kallsyms]) forkit 11019 [001] 66663.270833163: 1 instructions:k: ffffffffb230a825 irqentry_exit_to_user_mode+0x15 ([kernel.kallsyms]) forkit 11019 [001] 66663.271092359: 1 instructions:k: ffffffffb1aea3d9 lock_page_memcg+0x9 ([kernel.kallsyms]) forkit 11019 [001] 66663.271207092: PERF_RECORD_FORK(11020:11020):(11019:11019) forkit 11019 [001] 66663.271234775: PERF_RECORD_SWITCH_CPU_WIDE OUT next pid/tid: 11020/11020 forkit 11020 [001] 66663.271238407: PERF_RECORD_SWITCH_CPU_WIDE IN prev pid/tid: 11019/11019 forkit 11020 [001] 66663.271312066: 1 instructions:k: ffffffffb1a88140 handle_mm_fault+0x10 ([kernel.kallsyms]) forkit 11020 [001] 66663.271476225: PERF_RECORD_EXIT(11020:11020):(11019:11019) forkit 11020 [001] 66663.271497488: PERF_RECORD_SWITCH_CPU_WIDE OUT preempt next pid/tid: 11019/11019 forkit 11019 [001] 66663.271500523: PERF_RECORD_SWITCH_CPU_WIDE IN prev pid/tid: 11020/11020 forkit 11019 [001] 66663.271517241: 1 instructions:k: ffffffffb24012cd error_entry+0x6d ([kernel.kallsyms]) forkit 11019 [001] 66663.271664080: PERF_RECORD_EXIT(11019:11019):(1386:1386) forkit 11019 [001] 66663.271688752: PERF_RECORD_SWITCH_CPU_WIDE OUT next pid/tid: -1/-1 :-1 -1 [001] 66663.271692086: PERF_RECORD_SWITCH_CPU_WIDE IN prev pid/tid: 11019/11019 :-1 -1 [001] 66663.271707466: 1 instructions:k: ffffffffb18eb096 update_load_avg+0x306 ([kernel.kallsyms]) Fixes: 86c2786994bd7c ("perf intel-pt: Add support for PERF_RECORD_SWITCH") Signed-off-by: Adrian Hunter Cc: Andi Kleen Cc: Jiri Olsa Cc: Yu-cheng Yu Link: http://lore.kernel.org/lkml/20200909084923.9096-3-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin

perf cs-etm: Move definition of 'traceid_list' global variable from header file

2020-10-17T08:12:56+00:00

commit 168200b6d6ea0cb5765943ec5da5b8149701f36a upstream. The variable 'traceid_list' is defined in the header file cs-etm.h, if multiple C files include cs-etm.h the compiler might complaint for multiple definition of 'traceid_list'. To fix multiple definition error, move the definition of 'traceid_list' into cs-etm.c. Fixes: cd8bfd8c973e ("perf tools: Add processing of coresight metadata") Reported-by: Thomas Backlund Signed-off-by: Leo Yan Reviewed-by: Mathieu Poirier Reviewed-by: Mike Leach Tested-by: Mike Leach Tested-by: Thomas Backlund Cc: Alexander Shishkin Cc: Jiri Olsa Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Suzuki Poulouse Cc: Tor Jeremiassen Cc: linux-arm-kernel@lists.infradead.org Link: http://lore.kernel.org/lkml/20200505133642.4756-1-leo.yan@linaro.org Signed-off-by: Arnaldo Carvalho de Melo Cc: Paul Barker Signed-off-by: Greg Kroah-Hartman

perf top: Fix stdio interface input handling with glibc 2.28+

2020-10-14T08:31:22+00:00

commit 29b4f5f188571c112713c35cc87eefb46efee612 upstream. Since glibc 2.28 when running 'perf top --stdio', input handling no longer works, but hitting any key always just prints the "Mapped keys" help text. To fix it, call clearerr() in the display_thread() loop to clear any EOF sticky errors, as instructed in the glibc NEWS file (https://sourceware.org/git/?p=glibc.git;a=blob;f=NEWS): * All stdio functions now treat end-of-file as a sticky condition. If you read from a file until EOF, and then the file is enlarged by another process, you must call clearerr or another function with the same effect (e.g. fseek, rewind) before you can read the additional data. This corrects a longstanding C99 conformance bug. It is most likely to affect programs that use stdio to read interactive input from a terminal. (Bug #1190.) Signed-off-by: Tommi Rantala Tested-by: Arnaldo Carvalho de Melo Cc: Alexander Shishkin Cc: Jiri Olsa Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Link: http://lore.kernel.org/lkml/20200305083714.9381-2-tommi.t.rantala@nokia.com Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Greg Kroah-Hartman

objtool: Fix noreturn detection for ignored functions

2020-10-01T11:14:50+00:00

[ Upstream commit db6c6a0df840e3f52c84cc302cc1a08ba11a4416 ] When a function is annotated with STACK_FRAME_NON_STANDARD, objtool doesn't validate its code paths. It also skips sibling call detection within the function. But sibling call detection is actually needed for the case where the ignored function doesn't have any return instructions. Otherwise objtool naively marks the function as implicit static noreturn, which affects the reachability of its callers, resulting in "unreachable instruction" warnings. Fix it by just enabling sibling call detection for ignored functions. The 'insn->ignore' check in add_jump_destinations() is no longer needed after e6da9567959e ("objtool: Don't use ignore flag for fake jumps"). Fixes the following warning: arch/x86/kvm/vmx/vmx.o: warning: objtool: vmx_handle_exit_irqoff()+0x142: unreachable instruction which triggers on an allmodconfig with CONFIG_GCOV_KERNEL unset. Reported-by: Linus Torvalds Signed-off-by: Josh Poimboeuf Signed-off-by: Borislav Petkov Acked-by: Linus Torvalds Link: https://lkml.kernel.org/r/5b1e2536cdbaa5246b60d7791b76130a74082c62.1599751464.git.jpoimboe@redhat.com Signed-off-by: Sasha Levin

perf parse-events: Use strcmp() to compare the PMU name

2020-10-01T11:14:49+00:00

[ Upstream commit 8510895bafdbf7c4dd24c22946d925691135c2b2 ] A big uncore event group is split into multiple small groups which only include the uncore events from the same PMU. This has been supported in the commit 3cdc5c2cb924a ("perf parse-events: Handle uncore event aliases in small groups properly"). If the event's PMU name starts to repeat, it must be a new event. That can be used to distinguish the leader from other members. But now it only compares the pointer of pmu_name (leader->pmu_name == evsel->pmu_name). If we use "perf stat -M LLC_MISSES.PCIE_WRITE -a" on cascadelakex, the event list is: evsel->name evsel->pmu_name --------------------------------------------------------------- unc_iio_data_req_of_cpu.mem_write.part0 uncore_iio_4 (as leader) unc_iio_data_req_of_cpu.mem_write.part0 uncore_iio_2 unc_iio_data_req_of_cpu.mem_write.part0 uncore_iio_0 unc_iio_data_req_of_cpu.mem_write.part0 uncore_iio_5 unc_iio_data_req_of_cpu.mem_write.part0 uncore_iio_3 unc_iio_data_req_of_cpu.mem_write.part0 uncore_iio_1 unc_iio_data_req_of_cpu.mem_write.part1 uncore_iio_4 ...... For the event "unc_iio_data_req_of_cpu.mem_write.part1" with "uncore_iio_4", it should be the event from PMU "uncore_iio_4". It's not a new leader for this PMU. But if we use "(leader->pmu_name == evsel->pmu_name)", the check would be failed and the event is stored to leaders[] as a new PMU leader. So this patch uses strcmp to compare the PMU name between events. Fixes: d4953f7ef1a2 ("perf parse-events: Fix 3 use after frees found with clang ASAN") Signed-off-by: Jin Yao Acked-by: Jiri Olsa Cc: Alexander Shishkin Cc: Andi Kleen Cc: Jin Yao Cc: Kan Liang Cc: Peter Zijlstra Link: http://lore.kernel.org/lkml/20200430003618.17002-1-yao.jin@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin

selftests/x86/syscall_nt: Clear weird flags after each test

2020-10-01T11:14:49+00:00

[ Upstream commit a61fa2799ef9bf6c4f54cf7295036577cececc72 ] Clear the weird flags before logging to improve strace output -- logging results while, say, TF is set does no one any favors. Signed-off-by: Andy Lutomirski Signed-off-by: Thomas Gleixner Link: https://lkml.kernel.org/r/907bfa5a42d4475b8245e18b67a04b13ca51ffdb.1593191971.git.luto@kernel.org Signed-off-by: Sasha Levin