Commit 48fbcd4d authored Mar 09, 2026 by Wander Lairson Costa Committed by Tomas Glozar Mar 11, 2026

rtla/timerlat: Simplify RTLA_NO_BPF environment variable check



The code that checks the RTLA_NO_BPF environment variable calls
getenv() twice and uses strncmp() with a length of 2 to compare
against the single-character string "1". This is inefficient and
the comparison length is unnecessarily long.

Store the result of getenv() in a local variable to avoid the
redundant call, and replace strncmp() with strncmp_static() for
the exact match comparison. This follows the same pattern
established in recent commits that improved string comparison
consistency throughout the rtla codebase.

Signed-off-by: Wander Lairson Costa <wander@redhat.com>
Link: https://lore.kernel.org/r/20260309195040.1019085-15-wander@redhat.com


Signed-off-by: Tomas Glozar <tglozar@redhat.com>

parent ea5ea835

tools/tracing/rtla/src/timerlat.c

+2 −1

Original line number	Diff line number	Diff line
		@@ -28,12 +28,13 @@ int
		timerlat_apply_config(struct osnoise_tool tool, struct timerlat_params params)
		{
		int retval;
		const char *const rtla_no_bpf = getenv("RTLA_NO_BPF");

		/*
		* Try to enable BPF, unless disabled explicitly.
		* If BPF enablement fails, fall back to tracefs mode.
		*/
		if (getenv("RTLA_NO_BPF") && strncmp(getenv("RTLA_NO_BPF"), "1", 2) == 0) {
		if (rtla_no_bpf && strncmp_static(rtla_no_bpf, "1") == 0) {
		debug_msg("RTLA_NO_BPF set, disabling BPF\n");
		params->mode = TRACING_MODE_TRACEFS;
		} else if (!tep_find_event_by_name(tool->trace.tep, "osnoise", "timerlat_sample")) {