kernel/linux.git/tools/perf/tests/code-reading.c, branch v6.19.11

perf test: Switch cycles event to cpu-cycles

2025-10-15T14:59:12+00:00

Without a PMU perf matches an event against any PMU with the event. Unfortunately some PMU drivers advertise a "cycles" event which is typically just a core event. As tests assume a core event, switch to use "cpu-cycles" that avoids the overloaded "cycles" event on troublesome PMUs and is so far not overloaded. Note, on x86 this changes a legacy event into a sysfs one. Signed-off-by: Ian Rogers Tested-by: James Clark Signed-off-by: Namhyung Kim

perf tests: use strdup() in "Object code reading"

2025-10-13T08:58:51+00:00

Use strdup() instead of fixed PATH_MAX buffer for storing paths to not waste memory. Suggested-by: Ian Rogers Reviewed-by: Ian Rogers Signed-off-by: James Clark Signed-off-by: Namhyung Kim

perf tests: Don't retest sections in "Object code reading"

2025-10-06T19:59:11+00:00

We already only test each kcore map once, but on slow systems (particularly with network filesystems) even the non-kcore maps are slow. The test can test the same objdump output over and over which only wastes time. Generalize the skipping mechanism to track all DSOs and addresses so that each section is only tested once. On a fully loaded ARM Juno (simulating a parallel 'perf test' run) with a network filesystem, the original runtime is: real 1m51.126s user 0m19.445s sys 1m15.431s And the new runtime is: real 0m48.873s user 0m8.031s sys 0m32.353s Committer testing: # perf test "code read" 22: Object code reading : Ok # Reviewed-by: Ian Rogers Signed-off-by: James Clark Tested-by: Arnaldo Carvalho de Melo Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Ingo Molnar Cc: Jiri Olsa Cc: Leo Yan Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Signed-off-by: Arnaldo Carvalho de Melo

perf machine: Explicitly pass in host perf_env

2025-07-25T17:37:57+00:00

When creating a machine for the host explicitly pass in a scoped perf_env. This removes a use of the global perf_env. Signed-off-by: Ian Rogers Link: https://lore.kernel.org/r/20250724163302.596743-17-irogers@google.com Signed-off-by: Namhyung Kim

perf test: Avoid use perf_env

2025-07-25T17:37:57+00:00

The perf_env global variable holds the host perf_env data but its use is hit and miss. Switch to using local perf_env variables and ensure scoped perf_env__init and perf_env__exit. This loses command line setting of the perf_env, but this doesn't matter for tests. So the perf_env is fully initialized, clear it with memset in perf_env__init. Signed-off-by: Ian Rogers Link: https://lore.kernel.org/r/20250724163302.596743-13-irogers@google.com Signed-off-by: Namhyung Kim

perf test code-reading: Avoid a leak of cpus and threads

2025-07-03T02:05:26+00:00

The perf_evlist__set_maps does the necessary gets on the arguments passed, so the reference count bumping isn't necessary and creates a memory leak. Signed-off-by: Ian Rogers Link: https://lore.kernel.org/r/20250624190326.2038704-3-irogers@google.com Signed-off-by: Namhyung Kim

perf sample: Make user_regs and intr_regs optional

2025-02-13T04:06:11+00:00

The struct dump_regs contains 512 bytes of cache_regs, meaning the two values in perf_sample contribute 1088 bytes of its total 1384 bytes size. Initializing this much memory has a cost reported by Tavian Barnes as about 2.5% when running `perf script --itrace=i0`: https://lore.kernel.org/lkml/d841b97b3ad2ca8bcab07e4293375fb7c32dfce7.1736618095.git.tavianator@tavianator.com/ Adrian Hunter replied that the zero initialization was necessary and couldn't simply be removed. This patch aims to strike a middle ground of still zeroing the perf_sample, but removing 79% of its size by make user_regs and intr_regs optional pointers to zalloc-ed memory. To support the allocation accessors are created for user_regs and intr_regs. To support correct cleanup perf_sample__init and perf_sample__exit functions are created and added throughout the code base. Signed-off-by: Ian Rogers Link: https://lore.kernel.org/r/20250113194345.1537821-1-irogers@google.com Signed-off-by: Namhyung Kim

perf tests code-reading: Handle change in objdump output from binutils >= 2.41 on riscv

2025-01-08T20:20:42+00:00

After binutils commit e43d876 which was first included in binutils 2.41, riscv no longer supports dumping in the middle of instructions. Increase the objdump window by 2-bytes to ensure that any instruction that sits on the boundary of the specified stop-address is not cut in half. Signed-off-by: Charlie Jenkins Cc: Adrian Hunter Cc: Albert Ou Cc: Alexander Shishkin Cc: Bill Wendling Cc: Ian Rogers Cc: Ingo Molnar Cc: Jiri Olsa Cc: Justin Stitt Cc: Mark Rutland Cc: Namhyung Kim Cc: Nathan Chancellor Cc: Nick Desaulniers Cc: Palmer Dabbelt Cc: Paul Walmsley Cc: Peter Zijlstra Cc: linux-riscv@lists.infradead.org Link: https://lore.kernel.org/r/20241219-perf_fix_riscv_obj_reading-v3-1-a7d644dcfa50@rivosinc.com Signed-off-by: Arnaldo Carvalho de Melo

perf dso: Add reference count checking and accessor functions

2024-05-06T18:28:49+00:00

Add reference count checking to struct dso, this can help with implementing correct reference counting discipline. To avoid RC_CHK_ACCESS everywhere, add accessor functions for the variables in struct dso. The majority of the change is mechanical in nature and not easy to split up. Committer testing: 'perf test' up to this patch shows no regressions. But: util/symbol.c: In function ‘dso__load_bfd_symbols’: util/symbol.c:1683:9: error: too few arguments to function ‘dso__set_adjust_symbols’ 1683 | dso__set_adjust_symbols(dso); | ^~~~~~~~~~~~~~~~~~~~~~~ In file included from util/symbol.c:21: util/dso.h:268:20: note: declared here 268 | static inline void dso__set_adjust_symbols(struct dso *dso, bool val) | ^~~~~~~~~~~~~~~~~~~~~~~ make[6]: *** [/home/acme/git/perf-tools-next/tools/build/Makefile.build:106: /tmp/tmp.ZWHbQftdN6/util/symbol.o] Error 1 MKDIR /tmp/tmp.ZWHbQftdN6/tests/workloads/ make[6]: *** Waiting for unfinished jobs.... This was updated: - symbols__fixup_end(&dso->symbols, false); - symbols__fixup_duplicate(&dso->symbols); - dso->adjust_symbols = 1; + symbols__fixup_end(dso__symbols(dso), false); + symbols__fixup_duplicate(dso__symbols(dso)); + dso__set_adjust_symbols(dso); But not build tested with BUILD_NONDISTRO and libbfd devel files installed (binutils-devel on fedora). Add the missing argument: symbols__fixup_end(dso__symbols(dso), false); symbols__fixup_duplicate(dso__symbols(dso)); - dso__set_adjust_symbols(dso); + dso__set_adjust_symbols(dso, true); Signed-off-by: Ian Rogers Tested-by: Arnaldo Carvalho de Melo Cc: Adrian Hunter Cc: Ahelenia Ziemiańska Cc: Alexander Shishkin Cc: Andi Kleen Cc: Athira Rajeev Cc: Ben Gainey Cc: Changbin Du Cc: Chengen Du Cc: Colin Ian King Cc: Dima Kogan Cc: Ilkka Koskinen Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: K Prateek Nayak Cc: Kan Liang Cc: Leo Yan Cc: Li Dong Cc: Mark Rutland Cc: Masami Hiramatsu Cc: Namhyung Kim Cc: Paran Lee Cc: Peter Zijlstra Cc: Song Liu Cc: Sun Haiyong Cc: Thomas Richter Cc: Tiezhu Yang Cc: Yanteng Si Cc: zhaimingbing Link: https://lore.kernel.org/r/20240504213803.218974-6-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf tests: Apply attributes to all events in object code reading test

2024-04-12T15:02:05+00:00

PERF_PMU_CAP_EXTENDED_HW_TYPE results in multiple events being opened on heterogeneous systems. Currently this test only sets its required attributes on the first event. Not disabling enable_on_exec on the other events causes the test to fail because the forked objdump processes are sampled. No tracking event is opened so Perf only knows about its own mappings causing the objdump samples to give the following error: $ perf test -vvv "object code reading" Reading object code for memory address: 0xffff9aaa55ec thread__find_map failed ---- end(-1) ---- 24: Object code reading : FAILED! Fixes: 251aa040244a3b17 ("perf parse-events: Wildcard most "numeric" events") Reviewed-by: Ian Rogers Signed-off-by: James Clark Acked-by: Namhyung Kim Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Athira Rajeev Cc: Ian Rogers Cc: Ingo Molnar Cc: Jiri Olsa Cc: Kan Liang Cc: Leo Yan Cc: Mark Rutland Cc: Peter Zijlstra Cc: Spoorthy S Link: https://lore.kernel.org/r/20240410103458.813656-3-james.clark@arm.com Signed-off-by: Arnaldo Carvalho de Melo