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2026-06-23Merge tag 'perf-tools-for-v7.2-1-2026-06-22' of ↵Linus Torvalds11-183/+32
git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools Pull perf tools updates from Arnaldo Carvalho de Melo: - Introduce 'perf inject --aslr' to remap ASLR-randomized addresses in perf.data files, enabling reproducible analysis across runs with different address space layouts - Refactor evsel out of sample processing paths: store evsel in struct perf_sample and remove the redundant evsel parameter from tool APIs, tracepoint handlers, hist entry iterators, and db-export, simplifying the entire tool callback chain - Switch architecture detection from string-based perf_env__arch() comparisons to the numeric ELF e_machine field across the codebase (capstone, print_insn, c2c, lock-contention, sort, sample-raw, machine, header), making cross-analysis more robust - Overhaul ARM CoreSight ETM tests: add deterministic and named_threads workloads, speed up basic and disassembly tests, add process attribution and concurrent threads tests, remove unused workloads and duplicate tests, queue context packets for the frontend decoder - Add ARM SPE IMPDEF event decoding for Arm Neoverse N1, store MIDR in arm_spe_pkt for per-CPU event mapping, handle missing CPU IDs gracefully - Refactor libunwind support: remove the libunwind-local backend, make register reading cross-platform, add RISC-V libunwind support, allow dynamic selection between libdw and libunwind unwinding at runtime - Extensive hardening of perf.data parsing against crafted files: add bounds checks and byte-swap validation for session records, feature sections, header attributes, BPF metadata, auxtrace errors, compressed events, CPU maps, build ID notes, and ELF program headers. Add minimum event size validation and file offset diagnostics - Fix libdw API contract violations across dwarf-aux, libdw, probe-finder, annotate-data, and debuginfo subsystems. Fix callchain parent update in ORDER_CALLER mode, support DWARF line 0 in inline lists, handle multiple address spaces in callchains - Fix numerous 'perf sched' bugs: thread reference leaks, memory leaks, heap overflows with cross-machine recordings, NULL dereferences, replace BUG_ON assertions with graceful error handling, bounds-check CPU indices, fix SIGCHLD vs pause() races in sched stats - Overhaul the build system: move BPF skeleton generation out of Makefile.perf into bpf_skel.mak, decouple pmu-events from the prepare target, make beauty generated C code standalone .o files, compile BPF skeletons with -mcpu=v3, fix continuous rebuilds, various cleanups - Add 'perf test' JUnit XML reporting with -j/--junit option, split monolithic test suites into sub-tests, add summary reporting, refactor parallel poll loop, fix test failures on musl-based systems - Fix 'perf c2c' memory leaks in hist entry and format list handling, use-after-free in error paths, bounds-check CPU and node IDs - Fix 'perf bpf' metadata leaks on duplicate insert and alloc failure, bounds-check array offsets, validate event sizes and func_info fields, add NULL checks - Fix hwmon PMU: off-by-one null termination on sysfs reads, strlcpy buffer overflow in parse_hwmon_filename(), fd 0 check, empty label reads, scnprintf usage - Fix symbols subsystem: bounds-check ELF and sysfs build ID note iteration, validate p_filesz, fix 32-bit ELF bswap error, fix signed overflow in size checks, bounds-check .gnu_debuglink section - Fix tools lib api: null termination in filename__read_int/ull(), uninitialized stack data in filename__write_int(), snprintf truncation in mount_overload() - Replace libbabeltrace with babeltrace2-ctf-writer for CTF conversion in 'perf data' - Add RISC-V SDT argument parsing for static tracepoints - Add 'perf trace --show-cpu' option to display CPU id - Add 'perf bench sched pipe --write-size' option - Add a perf-specific .clang-format that overrides some kernel style behaviors - Update Intel vendor events for Alder Lake, Arrow Lake, Clearwater Forest, Emerald Rapids, Granite Rapids, Grand Ridge, Lunar Lake, Meteor Lake, Panther Lake, Sapphire Rapids, Sierra Forest - Add IOMMU metrics for AMD and Intel - Fix AMD event: switch l2_itlb_misses to bp_l1_tlb_miss_l2_tlb_miss.all - Add AMD IBS improvements: decode Streaming-store and Remote-Socket flags, suppress bogus fields on Zen4+, skip privilege test on Zen6+ - Fix 'perf lock contention' SIGCHLD vs pause() race, allow 'mmap_lock' in -L filter, enable end-timestamp for cgroup aggregation, fix non-atomic data updates - Fix 'perf stat' false NMI watchdog warning in aggregation modes, bounds-check CPU index in topology callbacks, add aggr_nr metric parser support for uncore scaling - Fix 'perf timechart' memory leaks, CPU bounds checking, use-after-free on corrupted callchains - Fix 'perf inject' itrace branch stack synthesis, fix synthesized sample size with branch stacks - Fix DSO heap overflow on decompressed paths, uninitialized pathname on fallback, set proper error codes - Fix various snprintf/scnprintf usages to prevent buffer overflows and truncation across the codebase - Fix off-by-one stack buffer overflow in kallsyms__parse() - Fix 'perf kwork' memory management, address sanitizer issues, bounds check work->cpu - Fix 'perf tpebs' concurrent stop races and PID reuse hazards - Add O_CLOEXEC to open() calls and use mkostemp() for temporary files to prevent file descriptor leaks to child processes - Fix s390 Python extension TEXTREL by compiling as PIC - Fix build with ASAN for jitdump - Fix build failure due to btf_vlen() return type change * tag 'perf-tools-for-v7.2-1-2026-06-22' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools: (343 commits) perf bpf: Fix up build failure due to change of btf_vlen() return type perf dso: Set standard errno on decompression failure perf bpf: Validate array presence before casting BPF prog info pointers perf c2c: Fix hist entry and format list leaks in c2c_he_free() perf c2c: Free format list entries when c2c_hists__init() fails perf cs-etm: Bounds-check CPU in cs_etm__get_queue() perf cs-etm: Require full global header in auxtrace_info size check perf cs-etm: Validate num_cpu before metadata allocation perf machine: Use snprintf() for guestmount path construction perf machine: Propagate machine__init() error to callers perf trace: Guard __probe_ip suppression with evsel__is_probe() perf evsel: Add lazy-initialized probe type detection helpers perf evsel: Add no-libtraceevent stubs for evsel__field() and evsel__common_field() perf cs-etm: Reject CPU IDs that would overflow signed comparison perf c2c: Free format list entries when releasing c2c hist entries perf bpf: Bounds-check array offsets in bpil_offs_to_addr() perf bpf: Reject oversized BPF metadata events that truncate header.size perf bpf: Validate func_info_rec_size and sub_id in synthesize_bpf_prog_name() perf sched: Replace (void*)1 sentinel with proper runtime allocation perf hwmon: Fix fd check to accept fd 0 in hwmon_pmu__describe_items() ...
2026-06-04perf data ctf: replace libbabeltrace with babeltrace2-ctf-writerMichael Jeanson3-8/+7
The 1.x branch of Babeltrace has been superseded by 2.x in 2020 and has been unmaintained since 2022, efforts have started to remove it from popular distributions. Babeltrace 2.x offers a very similar 'ctf-writer' library that can be used with minimal changes for the '--to-ctf' feature and has been packaged since Debian 11 and Fedora 32. This patch replaces the 'libbabeltrace' build feature with 'babeltrace2-ctf-writer' using pkgconfig detection, adjusts the naming of the public headers and applies minor API cleanups. There is no changes to the output ctf traces, the ctf-writer API still implements version 1.8 of the CTF specification that can be read by either Babeltrace 1 / 2 or any CTF compliant reader. Also remove some ifdefs in the cli option parsing to allow printing the helpful error message with '--to-ctf' when built without babeltrace2. Reviewed-by: Ian Rogers <irogers@google.com> Signed-off-by: Michael Jeanson <mjeanson@efficios.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Derek Foreman <derek.foreman@collabora.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Clark <james.clark@linaro.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-06-04tools build: Fix feature checks to touch target files on successIan Rogers1-6/+7
In tools/build/feature/Makefile, test-clang-bpf-co-re.bin and test-bpftool-skeletons.bin redirected grep output but never touched or created the $@ target file upon success. Because the target file was never created on disk, Kbuild could never cache the result of the check. Consequently, Make treated the prerequisite as missing and continuously re-executed the Clang BPF backend and bpftool feature checks on every single sub-make evaluation during build startup, or on every incremental build. Refactor both feature check recipes to touch $@ on success. For test-clang-bpf-co-re.bin, group the shell pipeline within curly braces and redirect both stdout and stderr to .make.output to allow errors to be inspected and not appear in build output. List test-clang-bpf-co-re.bin's input C file as a dependency so modification triggers a rebuild. For test-bpftool-skeletons.bin, add it to the FILES list so that it will be cleaned. Assisted-by: Gemini:gemini-3.1-pro-preview Signed-off-by: Ian Rogers <irogers@google.com> Tested-by: James Clark <james.clark@linaro.org> Cc: Bill Wendling <morbo@google.com> Cc: Costa Shulyupin <costa.shul@redhat.com> Cc: Dmitrii Dolgov <9erthalion6@gmail.com> Cc: Justin Stitt <justinstitt@google.com> Cc: Leo Yan <leo.yan@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Nick Desaulniers <nick.desaulniers+lkml@gmail.com> Cc: Yuzhuo Jing <yuzhuo@google.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-05-28libbpf: Add __NR_bpf definition for LoongArchTiezhu Yang1-0/+2
LoongArch uses the generic syscall table, where __NR_bpf is defined as 280 in include/uapi/asm-generic/unistd.h. To align with other architectures, add the __NR_bpf definition for LoongArch to avoid a potential compilation failure: "error __NR_bpf not defined. libbpf does not support your arch." This is a follow up patch of: commit b0c47807d31d ("bpf: Add sparc support to tools and samples.") commit bad1926dd2f6 ("bpf, s390: fix build for libbpf and selftest suite") commit ca31ca8247e2 ("tools/bpf: fix perf build error with uClibc (seen on ARC)") commit e32cb12ff52a ("bpf, mips: Fix build errors about __NR_bpf undeclared") Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Link: https://lore.kernel.org/bpf/20260526063936.16769-1-yangtiezhu@loongson.cn
2026-05-15tools build: Deduplicate test-libunwind for different architecturesIan Rogers9-172/+21
The separate test files only exist to pass a different #include, instead have a single source file and pass -include to $(CC) to include the relevant header file for the architecture being tested. Generate the rules using a foreach loop. Include tests for all current libunwind architectures. Signed-off-by: Ian Rogers <irogers@google.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexandre Ghiti <alex@ghiti.fr> Cc: Andrew Jones <andrew.jones@oss.qualcomm.com> Cc: Athira Rajeev <atrajeev@linux.ibm.com> Cc: Dapeng Mi <dapeng1.mi@linux.intel.com> Cc: Dmitrii Dolgov <9erthalion6@gmail.com> Cc: Florian Fainelli <florian.fainelli@broadcom.com> Cc: Howard Chu <howardchu95@gmail.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Clark <james.clark@linaro.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: John Garry <john.g.garry@oracle.com> Cc: Leo Yan <leo.yan@linux.dev> Cc: Li Guan <guanli.oerv@isrc.iscas.ac.cn> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Walmsley <pjw@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Shimin Guo <shimin.guo@skydio.com> Cc: Thomas Richter <tmricht@linux.ibm.com> Cc: Tomas Glozar <tglozar@redhat.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-04-18Merge tag 'perf-tools-for-v7.1-2026-04-17' of ↵Linus Torvalds1-2/+8
git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools Pull perf tools updates from Namhyung Kim: "perf report: - Add 'comm_nodigit' sort key to combine similar threads that only have different numbers in the comm. In the following example, the 'comm_nodigit' will have samples from all threads starting with "bpfrb/" into an entry "bpfrb/<N>". $ perf report -s comm_nodigit,comm -H ... # # Overhead CommandNoDigit / Command # ........... ........................ # 20.30% swapper 20.30% swapper 13.37% chrome 13.37% chrome 10.07% bpfrb/<N> 7.47% bpfrb/0 0.70% bpfrb/1 0.47% bpfrb/3 0.46% bpfrb/2 0.25% bpfrb/4 0.23% bpfrb/5 0.20% bpfrb/6 0.14% bpfrb/10 0.07% bpfrb/7 - Support flat layout for symfs. The --symfs option is to specify the location of debugging symbol files. The default 'hierarchy' layout would search the symbol file using the same path of the original file under the symfs root. The new 'flat' layout would search only in the root directory. - Update 'simd' sort key for ARM SIMD flags to cover ASE/SME and more predicate flags. perf stat: - Add --pmu-filter option to select specific PMUs. This would be useful when you measure metrics from multiple instance of uncore PMUs with similar names. # perf stat -M cpa_p0_avg_bw Performance counter stats for 'system wide': 19,417,779,115 hisi_sicl0_cpa0/cpa_cycles/ # 0.00 cpa_p0_avg_bw 0 hisi_sicl0_cpa0/cpa_p0_wr_dat/ 0 hisi_sicl0_cpa0/cpa_p0_rd_dat_64b/ 0 hisi_sicl0_cpa0/cpa_p0_rd_dat_32b/ 19,417,751,103 hisi_sicl10_cpa0/cpa_cycles/ # 0.00 cpa_p0_avg_bw 0 hisi_sicl10_cpa0/cpa_p0_wr_dat/ 0 hisi_sicl10_cpa0/cpa_p0_rd_dat_64b/ 0 hisi_sicl10_cpa0/cpa_p0_rd_dat_32b/ 19,417,730,679 hisi_sicl2_cpa0/cpa_cycles/ # 0.31 cpa_p0_avg_bw 75,635,749 hisi_sicl2_cpa0/cpa_p0_wr_dat/ 18,520,640 hisi_sicl2_cpa0/cpa_p0_rd_dat_64b/ 0 hisi_sicl2_cpa0/cpa_p0_rd_dat_32b/ 19,417,674,227 hisi_sicl8_cpa0/cpa_cycles/ # 0.00 cpa_p0_avg_bw 0 hisi_sicl8_cpa0/cpa_p0_wr_dat/ 0 hisi_sicl8_cpa0/cpa_p0_rd_dat_64b/ 0 hisi_sicl8_cpa0/cpa_p0_rd_dat_32b/ 19.417734480 seconds time elapsed With --pmu-filter, users can select only hisi_sicl2_cpa0 PMU. # perf stat --pmu-filter hisi_sicl2_cpa0 -M cpa_p0_avg_bw Performance counter stats for 'system wide': 6,234,093,559 cpa_cycles # 0.60 cpa_p0_avg_bw 50,548,465 cpa_p0_wr_dat 7,552,182 cpa_p0_rd_dat_64b 0 cpa_p0_rd_dat_32b 6.234139320 seconds time elapsed Data type profiling: - Quality improvements by tracking register state more precisely - Ensure array members to get the type - Handle more cases for global variables Vendor event/metric updates: - Update various Intel events and metrics - Add NVIDIA Tegra 410 Olympus events Internal changes: - Verify perf.data header for maliciously crafted files - Update perf test to cover more usages and make them robust - Move a couple of copied kernel headers not to annoy objtool build - Fix a bug in map sorting in name order - Remove some unused codes Misc: - Fix module symbol resolution with non-zero text address - Add -t/--threads option to `perf bench mem mmap` - Track duration of exit*() syscall by `perf trace -s` - Add core.addr2line-timeout and core.addr2line-disable-warn config items" * tag 'perf-tools-for-v7.1-2026-04-17' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools: (131 commits) perf loongarch: Fix build failure with CONFIG_LIBDW_DWARF_UNWIND perf annotate: Use jump__delete when freeing LoongArch jumps perf test: Fixes for check branch stack sampling perf test: Fix inet_pton probe failure and unroll call graph perf build: fix "argument list too long" in second location perf header: Add sanity checks to HEADER_BPF_BTF processing perf header: Sanity check HEADER_BPF_PROG_INFO perf header: Sanity check HEADER_PMU_CAPS perf header: Sanity check HEADER_HYBRID_TOPOLOGY perf header: Sanity check HEADER_CACHE perf header: Sanity check HEADER_GROUP_DESC perf header: Sanity check HEADER_PMU_MAPPINGS perf header: Sanity check HEADER_MEM_TOPOLOGY perf header: Sanity check HEADER_NUMA_TOPOLOGY perf header: Sanity check HEADER_CPU_TOPOLOGY perf header: Sanity check HEADER_NRCPUS and HEADER_CPU_DOMAIN_INFO perf header: Bump up the max number of command line args allowed perf header: Validate nr_domains when reading HEADER_CPU_DOMAIN_INFO perf sample: Fix documentation typo perf arm_spe: Improve SIMD flags setting ...
2026-03-26tools build: Correct link flags for libopensslLeo Yan1-2/+8
The perf static build reports that the BPF skeleton is disabled due to the missing libopenssl feature. Use PKG_CONFIG to determine the link flags for libopenssl. Add "--static" to the PKG_CONFIG command for static linking. Fixes: 7678523109d1 ("tools/build: Add a feature test for libopenssl") Signed-off-by: Leo Yan <leo.yan@arm.com> Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2026-03-04tools/build: Add feature test for libcheckCosta Shulyupin2-0/+12
Enable support for unit tests in rtla. Note that the pkg-config file for libcheck is named check.pc. Signed-off-by: Costa Shulyupin <costa.shul@redhat.com> Link: https://lore.kernel.org/r/20260119105857.797498-2-costa.shul@redhat.com Signed-off-by: Tomas Glozar <tglozar@redhat.com>
2026-02-12tools build: Fix feature test for rust compilerDmitrii Dolgov2-8/+6
Currently a dummy rust code is compiled to detect if the rust feature could be enabled. It turns out that in this case rust emits a dependency file without any external references: /perf/feature/test-rust.d: test-rust.rs /perf/feature/test-rust.bin: test-rust.rs test-rust.rs: This can lead to a situation, when rustc was removed after a successful build, but the build process still thinks it's there and the feature is enabled on subsequent runs. Instead simply check the compiler presence to detect the feature, as suggested by Arnaldo. This way no actual test-rust.bin will be created, meaning the feature check will not be cached and always performed. That's exactly what we want, and the overhead of doing this every time is minimal. Tested with multiple rounds of install/remove of the rust package. Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org> Suggested-by: Arnaldo Carvalho de Melo <acme@kernel.org> Signed-off-by: Dmitrii Dolgov <9erthalion6@gmail.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Ian Rogers <irogers@google.com> Cc: Miguel Ojeda <ojeda@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-02-10tools build: Emit dependencies file for test-rust.binDmitry Dolgov1-1/+1
Test it first by having rust installed, then removing it and building again. Fixes: 6a32fa5ccd33da5d ("tools build: Add a feature test for rust compiler") Signed-off-by: Dmitry Dolgov <9erthalion6@gmail.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-02-10tools build: Make test-rust.bin be removed by the 'clean' targetDmitrii Dolgov1-0/+1
test-rust.bin is missing from the list of FILES, and thus is not removed by the clean target. This could lead to a false feature detection, since the binary stays there. Fix it. Fixes: 6a32fa5ccd33da5d ("tools build: Add a feature test for rust compiler") Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Dmitrii Dolgov <9erthalion6@gmail.com> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-02-08tools build: Add a feature test for rust compilerDmitrii Dolgov2-0/+11
Add a feature test to identify if the rust compiler is available, so that perf could build rust based worloads based on that. Signed-off-by: Dmitrii Dolgov <9erthalion6@gmail.com> Cc: Ian Rogers <irogers@google.com> Cc: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-01-06perf build: Feature test for libbfd thread safety APIJames Clark2-0/+22
The non-distro build requires libbfd 2.42 since commit b72b8132d8fd ("perf libbfd: Ensure libbfd is initialized prior to use"). Add a feature test so that it's obvious why the build fails if this criteria isn't met. Signed-off-by: James Clark <james.clark@linaro.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Bill Wendling <morbo@google.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Justin Stitt <justinstitt@google.com> Cc: Leo Yan <leo.yan@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Nick Desaulniers <nick.desaulniers+lkml@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2026-01-06perf build: Remove unused libbfd-buildid feature testJames Clark2-12/+0
HAVE_LIBBFD_BUILDID_SUPPORT isn't used in the codebase so remove the feature test that sets it. Signed-off-by: James Clark <james.clark@linaro.org> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Bill Wendling <morbo@google.com> Cc: Ian Rogers <irogers@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Justin Stitt <justinstitt@google.com> Cc: Leo Yan <leo.yan@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Nick Desaulniers <nick.desaulniers+lkml@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2025-12-27tools build: Fix the common set of features test wrt libopensslArnaldo Carvalho de Melo1-1/+1
The recent introduction of the libopenssl feature test forgot to add the -lssl to the test-all.o target, which made it always fail, fix it. Noticed by looking at this file after building: $ cat /tmp/build/perf-tools/feature/test-all.make.output /usr/bin/ld: /tmp/ccBhO8WH.ltrans0.ltrans.o: in function `main': /home/acme/git/perf-tools/tools/build/feature/test-libopenssl.c:6:(.text.startup+0x2ed): undefined reference to `OPENSSL_init_ssl' collect2: error: ld returned 1 exit status $ It was added only to the individual ssl test, that works: $ cat /tmp/build/perf-tools/feature/test-libopenssl.make.output $ ldd /tmp/build/perf-tools/feature/test-libopenssl.bin | grep ssl libssl.so.3 => /usr/lib64/libssl.so.3 (0x00007fb81eda8000) $ Fixes: 7678523109d1d9ee ("tools/build: Add a feature test for libopenssl") Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-12-17tools/build: Add a feature test for libopensslNamhyung Kim3-2/+18
It's used by bpftool and the kernel build. Let's add a feature test so that perf can decide what to do based on the availability. Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-12-07Merge tag 'perf-tools-for-v6.19-2025-12-06' of ↵Linus Torvalds3-17/+0
git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools Pull perf tools updates from Namhyung Kim: "Perf event/metric description: Unify all event and metric descriptions in JSON format. Now event parsing and handling is greatly simplified by that. From users point of view, perf list will provide richer information about hardware events like the following. $ perf list hw List of pre-defined events (to be used in -e or -M): legacy hardware: branch-instructions [Retired branch instructions [This event is an alias of branches]. Unit: cpu] branch-misses [Mispredicted branch instructions. Unit: cpu] branches [Retired branch instructions [This event is an alias of branch-instructions]. Unit: cpu] bus-cycles [Bus cycles,which can be different from total cycles. Unit: cpu] cache-misses [Cache misses. Usually this indicates Last Level Cache misses; this is intended to be used in conjunction with the PERF_COUNT_HW_CACHE_REFERENCES event to calculate cache miss rates. Unit: cpu] cache-references [Cache accesses. Usually this indicates Last Level Cache accesses but this may vary depending on your CPU. This may include prefetches and coherency messages; again this depends on the design of your CPU. Unit: cpu] cpu-cycles [Total cycles. Be wary of what happens during CPU frequency scaling [This event is an alias of cycles]. Unit: cpu] cycles [Total cycles. Be wary of what happens during CPU frequency scaling [This event is an alias of cpu-cycles]. Unit: cpu] instructions [Retired instructions. Be careful,these can be affected by various issues,most notably hardware interrupt counts. Unit: cpu] ref-cycles [Total cycles; not affected by CPU frequency scaling. Unit: cpu] But most notable changes would be in the perf stat. On the right side, the default metrics are better named and aligned. :) $ perf stat -- perf test -w noploop Performance counter stats for 'perf test -w noploop': 11 context-switches # 10.8 cs/sec cs_per_second 0 cpu-migrations # 0.0 migrations/sec migrations_per_second 3,612 page-faults # 3532.5 faults/sec page_faults_per_second 1,022.51 msec task-clock # 1.0 CPUs CPUs_utilized 110,466 branch-misses # 0.0 % branch_miss_rate (88.66%) 6,934,452,104 branches # 6781.8 M/sec branch_frequency (88.66%) 4,657,032,590 cpu-cycles # 4.6 GHz cycles_frequency (88.65%) 27,755,874,218 instructions # 6.0 instructions insn_per_cycle (89.03%) TopdownL1 # 0.3 % tma_backend_bound # 9.3 % tma_bad_speculation (89.05%) # 9.7 % tma_frontend_bound (77.86%) # 80.7 % tma_retiring (88.81%) 1.025318171 seconds time elapsed 1.013248000 seconds user 0.012014000 seconds sys Deferred unwinding support: With the kernel support (commit c69993ecdd4d: "perf: Support deferred user unwind"), perf can use deferred callchains for userspace stack trace with frame pointers like below: $ perf record --call-graph fp,defer ... This will be transparent to users when it comes to other commands like perf report and perf script. They will merge the deferred callchains to the previous samples as if they were collected together. ARM SPE updates - Extensive enhancements to support various kinds of memory operations including GCS, MTE allocation tags, memcpy/memset, register access, and SIMD operations. - Add inverted data source filter (inv_data_src_filter) support to exclude certain data sources. - Improve documentation. Vendor event updates: - Intel: Updated event files for Sierra Forest, Panther Lake, Meteor Lake, Lunar Lake, Granite Rapids, and others. - Arm64: Added metrics for i.MX94 DDR PMU and Cortex-A720AE definitions. - RISC-V: Added JSON support for T-HEAD C920V2. Misc: - Improve pointer tracking in data type profiling. It'd give better output when the variable is using container_of() to convert type. - Annotation support for perf c2c report in TUI. Press 'a' key to enter annotation view from cacheline browser window. This will show which instruction is causing the cacheline contention. - Lots of fixes and test coverage improvements!" * tag 'perf-tools-for-v6.19-2025-12-06' of git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools: (214 commits) libperf: Use 'extern' in LIBPERF_API visibility macro perf stat: Improve handling of termination by signal perf tests stat: Add test for error for an offline CPU perf stat: When no events, don't report an error if there is none perf tests stat: Add "--null" coverage perf cpumap: Add "any" CPU handling to cpu_map__snprint_mask libperf cpumap: Fix perf_cpu_map__max for an empty/NULL map perf stat: Allow no events to open if this is a "--null" run perf test kvm: Add some basic perf kvm test coverage perf tests evlist: Add basic evlist test perf tests script dlfilter: Add a dlfilter test perf tests kallsyms: Add basic kallsyms test perf tests timechart: Add a perf timechart test perf tests top: Add basic perf top coverage test perf tests buildid: Add purge and remove testing perf tests c2c: Add a basic c2c perf c2c: Clean up some defensive gets and make asan clean perf jitdump: Fix missed dso__put perf mem-events: Don't leak online CPU map perf hist: In init, ensure mem_info is put on error paths ...
2025-11-13tool build: Remove __get_cpuid feature testIan Rogers3-17/+0
This feature test is no longer used so remove. The function tested by the feature test is used in: tools/power/x86/x86_energy_perf_policy/x86_energy_perf_policy.c however, the Makefile just assumes the presence of the function and doesn't perform a build feature test for it. Signed-off-by: Ian Rogers <irogers@google.com> Reviewed-by: James Clark <james.clark@linaro.org> Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-11-13perf build: Don't fail fast path feature detection when binutils-devel is ↵Arnaldo Carvalho de Melo1-2/+2
not available This is one more remnant of the BUILD_NONDISTRO series to make building with binutils-devel opt-in due to license incompatibility. In this case just the references at link time were still in place, which make building the test-all.bin file fail, which wasn't detected before probably because the last test was done with binutils-devel available, doh. Now: $ rpm -q binutils-devel package binutils-devel is not installed $ file /tmp/build/perf-tools/feature/test-all.bin /tmp/build/perf-tools/feature/test-all.bin: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, BuildID[sha1]=4b5388a346b51f1b993f0b0dbd49f4570769b03c, for GNU/Linux 3.2.0, not stripped $ Fixes: 970ae86307718c34 ("perf build: The bfd features are opt-in, stop testing for them by default") Reviewed-by: Ian Rogers <irogers@google.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: James Clark <james.clark@linaro.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2025-10-06perf build: Correct CROSS_ARCH for clangLeo Yan1-1/+1
Clang's -dumpmachine outputs "aarch64-unknown-linux-gnu", which does not match the MultiArch convention. This prevents the build system from detecting installed packages. Fix by stripping the trailing '-' from CROSS_COMPILE when setting CROSS_ARCH. Signed-off-by: Leo Yan <leo.yan@arm.com> Reviewed-by: Ian Rogers <irogers@google.com> Link: https://lore.kernel.org/r/20251006-perf_build_android_ndk-v3-3-4305590795b2@arm.com Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Alexandre Ghiti <alex@ghiti.fr> Cc: Nick Desaulniers <nick.desaulniers+lkml@gmail.com> Cc: Justin Stitt <justinstitt@google.com> Cc: Bill Wendling <morbo@google.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Nathan Chancellor <nathan@kernel.org> Cc: James Clark <james.clark@linaro.org> Cc: linux-riscv@lists.infradead.org Cc: llvm@lists.linux.dev Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: linux-kernel@vger.kernel.org Cc: linux-perf-users@vger.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2025-10-06tools build: Align warning options with perfLeo Yan1-2/+2
The feature test programs are built without enabling '-Wall -Werror' options. As a result, a feature may appear to be available, but later building in perf can fail with stricter checks. Make the feature test program use the same warning options as perf. Fixes: 1925459b4d92 ("tools build: Fix feature Makefile issues with 'O='") Signed-off-by: Leo Yan <leo.yan@arm.com> Reviewed-by: Ian Rogers <irogers@google.com> Link: https://lore.kernel.org/r/20251006-perf_build_android_ndk-v3-1-4305590795b2@arm.com Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Alexandre Ghiti <alex@ghiti.fr> Cc: Nick Desaulniers <nick.desaulniers+lkml@gmail.com> Cc: Justin Stitt <justinstitt@google.com> Cc: Bill Wendling <morbo@google.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Arnaldo Carvalho de Melo <acme@kernel.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Nathan Chancellor <nathan@kernel.org> Cc: James Clark <james.clark@linaro.org> Cc: linux-riscv@lists.infradead.org Cc: llvm@lists.linux.dev Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: linux-kernel@vger.kernel.org Cc: linux-perf-users@vger.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2025-10-03tools build: Remove libbpf-strings feature testIan Rogers2-14/+0
The feature test is unnecessary as the LIBBPF_CURRENT_VERSION_GEQ(1,7) macro can be used instead. The only use was in perf and this is now removed. Signed-off-by: Ian Rogers <irogers@google.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Blake Jones <blakejones@google.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2025-10-03tools build: Remove feature-libslang-include-subdirIan Rogers2-11/+0
Added in commit cbefd24f0aee3a5d ("tools build: Add test to check if slang.h is in /usr/include/slang/") this feature was to fix build support on now unsupported versions of RHEL 5 and 6. As 6 years has passed let's remove the workaround. Signed-off-by: Ian Rogers <irogers@google.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2025-10-03tools build: Remove get_current_dir_name feature checkIan Rogers3-20/+0
As perf no longer tests for this feature, and it was the only user, remove the feature test. Signed-off-by: Ian Rogers <irogers@google.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> [ Remove the call to main_test_get_current_dir_name() from main() in test-all.c, otherwise it will always fail ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2025-10-02tools build: Don't assume libtracefs-devel is always availableArnaldo Carvalho de Melo1-5/+0
perf doesn't use libtracefs and so it doesn't make sense to assume it is always available when building test-all.bin, defeating the feature check speedup it provides. The other tools/build/ users such as rtla, rv, etc call $(feature_check libtracefs) to check its availability instead of using the test-all.bin mechanism, stopping the build and asking for libtracefs-devel to be installed. Remove it from FEATURE_TESTS_BASIC to not have it as available, as noted by Ian Rogers during review. Reviewed-by: Ian Rogers <irogers@google.com> Acked-by: Tomas Glozar <tglozar@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Gabriele Monaco <gmonaco@redhat.com> Cc: James Clark <james.clark@linaro.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2025-09-19tools build: Make libperl opt-in rather than opt-out, deprecateIan Rogers1-7/+2
If libperl is installed then the perf tool build will build against it. There appears to be limited interest in the scripting support for perl so let's make it opt-in and deprecate it. With this patch applied you need to add LIBPERL=1 to get libperl support in perf - there is no warning if libperl is missing, but building will fail if libperl is missing and the build has LIBPERL=1. The perf version output is changed to: ``` $ perf version --build-options perf version 6.17.rc3.g8eca69269947 aio: [ on ] # HAVE_AIO_SUPPORT bpf: [ on ] # HAVE_LIBBPF_SUPPORT bpf_skeletons: [ on ] # HAVE_BPF_SKEL debuginfod: [ on ] # HAVE_DEBUGINFOD_SUPPORT dwarf: [ on ] # HAVE_LIBDW_SUPPORT dwarf_getlocations: [ on ] # HAVE_LIBDW_SUPPORT dwarf-unwind: [ on ] # HAVE_DWARF_UNWIND_SUPPORT auxtrace: [ on ] # HAVE_AUXTRACE_SUPPORT libbfd: [ OFF ] # HAVE_LIBBFD_SUPPORT ( tip: Deprecated, license incompatibility, use BUILD_NONDISTRO=1 and install binutils-dev[el] ) libbpf-strings: [ on ] # HAVE_LIBBPF_STRINGS_SUPPORT libcapstone: [ on ] # HAVE_LIBCAPSTONE_SUPPORT libdw-dwarf-unwind: [ on ] # HAVE_LIBDW_SUPPORT libelf: [ on ] # HAVE_LIBELF_SUPPORT libnuma: [ on ] # HAVE_LIBNUMA_SUPPORT libopencsd: [ OFF ] # HAVE_CSTRACE_SUPPORT libperl: [ OFF ] # HAVE_LIBPERL_SUPPORT ( tip: Deprecated, use LIBPERL=1 and install libperl-dev to build with it ) libpfm4: [ on ] # HAVE_LIBPFM libpython: [ on ] # HAVE_LIBPYTHON_SUPPORT libslang: [ on ] # HAVE_SLANG_SUPPORT libtraceevent: [ on ] # HAVE_LIBTRACEEVENT libunwind: [ OFF ] # HAVE_LIBUNWIND_SUPPORT ( tip: Deprecated, use LIBUNWIND=1 and install libunwind-dev[el] to build with it ) lzma: [ on ] # HAVE_LZMA_SUPPORT numa_num_possible_cpus: [ on ] # HAVE_LIBNUMA_SUPPORT zlib: [ on ] # HAVE_ZLIB_SUPPORT zstd: [ on ] # HAVE_ZSTD_SUPPORT ``` i.e. there is a tip saying about deprecation and how to get support back. Signed-off-by: Ian Rogers <irogers@google.com> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Charlie Jenkins <charlie@rivosinc.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Clark <james.clark@linaro.org> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Leo Yan <leo.yan@arm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Michael Petlan <mpetlan@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Quentin Monnet <qmo@kernel.org> Cc: Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: Tomas Glozar <tglozar@redhat.com> Cc: Yuzhuo Jing <yuzhuo@google.com> Link: https://lore.kernel.org/lkml/aMrk03gigBlGcYLK@x1/ Link: https://lore.kernel.org/lkml/CAP-5=fVX+bLBRJCiziDi_hBySgv2NFtDoghtpheSSxVAvvETGw@mail.gmail.com [ Keep the pre-existing perl-ExtUtils-Embed hint for Fedora/RHEL systems ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2025-06-26tools: Remove libcrypto dependencyYuzhuo Jing3-34/+0
Remove all occurrence of libcrypto in the build system. Signed-off-by: Yuzhuo Jing <yuzhuo@google.com> Signed-off-by: Eric Biggers <ebiggers@kernel.org> Reviewed-by: Ian Rogers <irogers@google.com> Link: https://lore.kernel.org/r/20250625202311.23244-5-ebiggers@kernel.org Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-06-24perf build: The bfd features are opt-in, stop testing for them by defaultArnaldo Carvalho de Melo1-19/+0
These are leftovers noticed while updating a build container. We don't need those so that test-all.c can build and thus speed up the feature detection. Test for those features only if the user asks for BUILD_NONDISTRO=1 to build with libbfd. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Reviewed-by: James Clark <james.clark@linaro.org> Reviewed-by: Ian Rogers <irogers@google.com> Link: https://lore.kernel.org/r/20250620212435.93846-4-acme@kernel.org Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-06-20perf build: detect support for libbpf's emit_strings optionBlake Jones2-0/+14
This creates a config option that detects libbpf's ability to display character arrays as strings, which was just added to the BPF tree (https://git.kernel.org/bpf/bpf-next/c/87c9c79a02b4). To test this change, I built perf (from later in this patch set) with: - static libbpf (default, using source from kernel tree) - dynamic libbpf (LIBBPF_DYNAMIC=1 LIBBPF_INCLUDE=/usr/local/include) For both the static and dynamic versions, I used headers with and without the ".emit_strings" option. I verified that of the four resulting binaries, the two with ".emit_strings" would successfully record BPF_METADATA events, and the two without wouldn't. All four binaries would successfully display BPF_METADATA events, because the relevant bit of libbpf code is only used during "perf record". Signed-off-by: Blake Jones <blakejones@google.com> Link: https://lore.kernel.org/r/20250612194939.162730-2-blakejones@google.com Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-06-09tools/build: Remove some unused libbpf pre-1.0 feature test logicIan Rogers1-21/+0
Commit 76a97cf2e169 ("perf build: Remove libbpf pre-1.0 feature tests") removed the libbpf feature test logic used by perf in favor of using LIBBPF_MAJOR_VERSION. Remove some build targets that should have been removed as part of that clean up. Fixes: 76a97cf2e169 ("perf build: Remove libbpf pre-1.0 feature tests") Signed-off-by: Ian Rogers <irogers@google.com> Link: https://lore.kernel.org/r/20250603221358.2562167-1-irogers@google.com Signed-off-by: Namhyung Kim <namhyung@kernel.org>
2025-03-31Merge tag 'perf-tools-for-v6.15-2025-03-27' of ↵Linus Torvalds8-8/+8
git://git.kernel.org/pub/scm/linux/kernel/git/perf/perf-tools Pull perf tools updates from Namhyung Kim: "perf record: - Introduce latency profiling using scheduler information. The latency profiling is to show impacts on wall-time rather than cpu-time. By tracking context switches, it can weight samples and find which part of the code contributed more to the execution latency. The value (period) of the sample is weighted by dividing it by the number of parallel execution at the moment. The parallelism is tracked in perf report with sched-switch records. This will reduce the portion that are run in parallel and in turn increase the portion of serial executions. For now, it's limited to profile processes, IOW system-wide profiling is not supported. You can add --latency option to enable this. $ perf record --latency -- make -C tools/perf I've run the above command for perf build which adds -j option to make with the number of CPUs in the system internally. Normally it'd show something like below: $ perf report -F overhead,comm ... # # Overhead Command # ........ ............... # 78.97% cc1 6.54% python3 4.21% shellcheck 3.28% ld 1.80% as 1.37% cc1plus 0.80% sh 0.62% clang 0.56% gcc 0.44% perl 0.39% make ... The cc1 takes around 80% of the overhead as it's the actual compiler. However it runs in parallel so its contribution to latency may be less than that. Now, perf report will show both overhead and latency (if --latency was given at record time) like below: $ perf report -s comm ... # # Overhead Latency Command # ........ ........ ............... # 78.97% 48.66% cc1 6.54% 25.68% python3 4.21% 0.39% shellcheck 3.28% 13.70% ld 1.80% 2.56% as 1.37% 3.08% cc1plus 0.80% 0.98% sh 0.62% 0.61% clang 0.56% 0.33% gcc 0.44% 1.71% perl 0.39% 0.83% make ... You can see latency of cc1 goes down to around 50% and python3 and ld contribute a lot more than their overhead. You can use --latency option in perf report to get the same result but ordered by latency. $ perf report --latency -s comm perf report: - As a side effect of the latency profiling work, it adds a new output field 'latency' and a sort key 'parallelism'. The below is a result from my system with 64 CPUs. The build was well-parallelized but contained some serial portions. $ perf report -s parallelism ... # # Overhead Latency Parallelism # ........ ........ ........... # 16.95% 1.54% 62 13.38% 1.24% 61 12.50% 70.47% 1 11.81% 1.06% 63 7.59% 0.71% 60 4.33% 12.20% 2 3.41% 0.33% 59 2.05% 0.18% 64 1.75% 1.09% 9 1.64% 1.85% 5 ... - Support Feodra mini-debuginfo which is a LZMA compressed symbol table inside ".gnu_debugdata" ELF section. perf annotate: - Add --code-with-type option to enable data-type profiling with the usual annotate output. Instead of focusing on data structure, it shows code annotation together with data type it accesses in case the instruction refers to a memory location (and it was able to resolve the target data type). Currently it only works with --stdio. $