WARNING: Use of volatile is usually wrong: see Documentation/process/volatile-considered-harmful.rst
#81: FILE: tools/testing/selftests/bpf/bench_bpf_timing.h:23:
+	volatile __u32 *timing_enabled;		/* &skel->bss->timing_enabled */

WARNING: Use of volatile is usually wrong: see Documentation/process/volatile-considered-harmful.rst
#82: FILE: tools/testing/selftests/bpf/bench_bpf_timing.h:24:
+	volatile __u32 *batch_iters_bss;	/* &skel->bss->batch_iters */

WARNING: line length of 81 exceeds 80 columns
#103: FILE: tools/testing/selftests/bpf/bench_bpf_timing.h:45:
+void bpf_bench_timing_measure(struct bpf_bench_timing *t, struct bench_res *res);

WARNING: line length of 93 exceeds 80 columns
#104: FILE: tools/testing/selftests/bpf/bench_bpf_timing.h:46:
+void bpf_bench_timing_report(struct bpf_bench_timing *t, const char *name, const char *desc);

WARNING: line length of 89 exceeds 80 columns
#105: FILE: tools/testing/selftests/bpf/bench_bpf_timing.h:47:
+void bpf_bench_calibrate(struct bpf_bench_timing *t, bpf_bench_run_fn run_fn, void *ctx);

WARNING: line length of 83 exceeds 80 columns
#217: FILE: tools/testing/selftests/bpf/benchs/bench_bpf_timing.c:104:
+/* Fixed bin width avoids sub-ns bins that make tight distributions look spread. */

WARNING: quoted string split across lines
#366: FILE: tools/testing/selftests/bpf/benchs/bench_bpf_timing.c:253:
+		printf("RESULT scenario=%s samples=%d median=%.2f stddev=%.2f"
+		       " cv=%.2f min=%.2f p90=%.2f p95=%.2f p99=%.2f max=%.2f\n",

WARNING: line length of 84 exceeds 80 columns
#389: FILE: tools/testing/selftests/bpf/benchs/bench_bpf_timing.c:276:
+	printf("  median %.*f ns/op, stddev %.*f, CV %.2f%% [min %.*f, max %.*f]\n",

WARNING: line length of 91 exceeds 80 columns
#398: FILE: tools/testing/selftests/bpf/benchs/bench_bpf_timing.c:285:
+		printf("  WARNING: only %d samples - tail percentiles may be unreliable\n",

WARNING: line length of 83 exceeds 80 columns
#404: FILE: tools/testing/selftests/bpf/benchs/bench_bpf_timing.c:291:
+		printf("  NOTE: right-skewed distribution (tail %.1fx the body)\n",

WARNING: line length of 92 exceeds 80 columns
#492: FILE: tools/testing/selftests/bpf/benchs/bench_bpf_timing.c:379:
+	elapsed = measure_elapsed(t, run_fn, run_ctx, CALIBRATE_SEED_BATCH, CALIBRATE_RUNS);

WARNING: line length of 83 exceeds 80 columns
#494: FILE: tools/testing/selftests/bpf/benchs/bench_bpf_timing.c:381:
+		fprintf(stderr, "calibration: no timing samples, using default\n");

WARNING: line length of 81 exceeds 80 columns
#505: FILE: tools/testing/selftests/bpf/benchs/bench_bpf_timing.c:392:
+		printf("Calibration: %llu ns/op, batch_iters=%u (~%ums/batch)\n",

WARNING: line length of 85 exceeds 80 columns
#509: FILE: tools/testing/selftests/bpf/benchs/bench_bpf_timing.c:396:
+	time_n = measure_elapsed(t, run_fn, run_ctx, t->batch_iters, CALIBRATE_RUNS);

WARNING: line length of 90 exceeds 80 columns
#510: FILE: tools/testing/selftests/bpf/benchs/bench_bpf_timing.c:397:
+	time_2n = measure_elapsed(t, run_fn, run_ctx, t->batch_iters * 2, CALIBRATE_RUNS);

WARNING: quoted string split across lines
#518: FILE: tools/testing/selftests/bpf/benchs/bench_bpf_timing.c:405:
+				"WARNING: proportionality check failed "
+				"(2N/N ratio=%.3f, expected=2.000, error=%.1f%%)\n"

CHECK: extern prototypes should be avoided in .h files
#544: FILE: tools/testing/selftests/bpf/progs/bench_bpf_timing.bpf.h:10:
+extern __u64 bpf_get_cpu_time_counter(void) __weak __ksym;

CHECK: extern prototypes should be avoided in .h files
#545: FILE: tools/testing/selftests/bpf/progs/bench_bpf_timing.bpf.h:11:
+extern __u64 bpf_cpu_time_counter_to_ns(__u64 counter) __weak __ksym;

WARNING: Use of volatile is usually wrong: see Documentation/process/volatile-considered-harmful.rst
#558: FILE: tools/testing/selftests/bpf/progs/bench_bpf_timing.bpf.h:24:
+volatile __u32 batch_iters;

WARNING: Use of volatile is usually wrong: see Documentation/process/volatile-considered-harmful.rst
#559: FILE: tools/testing/selftests/bpf/progs/bench_bpf_timing.bpf.h:25:
+volatile __u32 timing_enabled;

total: 0 errors, 18 warnings, 2 checks, 546 lines checked

NOTE: For some of the reported defects, checkpatch may be able to
      mechanically convert to the typical style using --fix or --fix-inplace.

Commit 8f767cfe4c51 ("selftests/bpf: Add BPF batch-timing library") has style problems, please review.

NOTE: Ignored message types: ALLOC_SIZEOF_STRUCT BAD_REPORTED_BY_LINK CAMELCASE COMMIT_LOG_LONG_LINE FILE_PATH_CHANGES GIT_COMMIT_ID MACRO_ARG_REUSE NO_AUTHOR_SIGN_OFF

NOTE: If any of the errors are false positives, please report
      them to the maintainer, see CHECKPATCH in MAINTAINERS.
total: 0 errors, 18 warnings, 2 checks, 546 lines checked