tools/rtla: Create common_apply_config()

Merge the common bits of osnoise_apply_config() and
timerlat_apply_config().  Put the result in a new common.c, and move
enough things to common.h so that common.c does not need to include
osnoise.h.

Cc: John Kacur <jkacur@redhat.com>
Cc: Costa Shulyupin <costa.shul@redhat.com>
Link: https://lore.kernel.org/20250907022325.243930-4-crwood@redhat.com
Reviewed-by: Tomas Glozar  <tglozar@redhat.com>
Signed-off-by: Crystal Wood <crwood@redhat.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

1 files changed, 63 insertions, 0 deletions

diff --git a/tools/tracing/rtla/src/common.c b/tools/tracing/rtla/src/common.c
new file mode 100644
index 000000000000..32a6faffc714
--- /dev/null
+++ b/tools/tracing/rtla/src/common.c
@@ -0,0 +1,63 @@
+// SPDX-License-Identifier: GPL-2.0
+#define _GNU_SOURCE
+
+#include <unistd.h>
+#include "common.h"
+
+/*
+ * common_apply_config - apply common configs to the initialized tool
+ */
+int
+common_apply_config(struct osnoise_tool *tool, struct common_params *params)
+{
+	int retval, i;
+
+	if (!params->sleep_time)
+		params->sleep_time = 1;
+
+	retval = osnoise_set_cpus(tool->context, params->cpus ? params->cpus : "all");
+	if (retval) {
+		err_msg("Failed to apply CPUs config\n");
+		goto out_err;
+	}
+
+	if (!params->cpus) {
+		for (i = 0; i < sysconf(_SC_NPROCESSORS_CONF); i++)
+			CPU_SET(i, &params->monitored_cpus);
+	}
+
+	if (params->hk_cpus) {
+		retval = sched_setaffinity(getpid(), sizeof(params->hk_cpu_set),
+					   &params->hk_cpu_set);
+		if (retval == -1) {
+			err_msg("Failed to set rtla to the house keeping CPUs\n");
+			goto out_err;
+		}
+	} else if (params->cpus) {
+		/*
+		 * Even if the user do not set a house-keeping CPU, try to
+		 * move rtla to a CPU set different to the one where the user
+		 * set the workload to run.
+		 *
+		 * No need to check results as this is an automatic attempt.
+		 */
+		auto_house_keeping(&params->monitored_cpus);
+	}
+
+	/*
+	 * Set workload according to type of thread if the kernel supports it.
+	 * On kernels without support, user threads will have already failed
+	 * on missing fd, and kernel threads do not need it.
+	 */
+	retval = osnoise_set_workload(tool->context, params->kernel_workload);
+	if (retval < -1) {
+		err_msg("Failed to set OSNOISE_WORKLOAD option\n");
+		goto out_err;
+	}
+
+	return 0;
+
+out_err:
+	return -1;
+}
+