tools/rtla: Add fatal() and replace error handling pattern

The code contains some technical debt in error handling,
which complicates the consolidation of duplicated code.

Introduce an fatal() function to replace the common pattern of
err_msg() followed by exit(EXIT_FAILURE), reducing the length of an
already long function.

Further patches using fatal() follow.

Signed-off-by: Costa Shulyupin <costa.shul@redhat.com>
Reviewed-by: Tomas Glozar <tglozar@redhat.com>
Link: https://lore.kernel.org/r/20251011082738.173670-2-costa.shul@redhat.com
Signed-off-by: Tomas Glozar <tglozar@redhat.com>

diff --git a/tools/tracing/rtla/src/osnoise_hist.c b/tools/tracing/rtla/src/osnoise_hist.c
index df0657b789804e54ddd4b3da57af4b1099f17542..d30a9a03b76473cb4d7428e17d8eb266fb8f5652 100644 (file)
--- a/tools/tracing/rtla/src/osnoise_hist.c
+++ b/tools/tracing/rtla/src/osnoise_hist.c
@@ -575,10 +575,8 @@ static struct common_params
                        break;
                case 'e':
                        tevent = trace_event_alloc(optarg);
-                       if (!tevent) {
-                               err_msg("Error alloc trace event");
-                               exit(EXIT_FAILURE);
-                       }
+                       if (!tevent)
+                               fatal("Error alloc trace event");
 
                        if (params->common.events)
                                tevent->next = params->common.events;
@@ -598,10 +596,8 @@ static struct common_params
                case 'H':
                        params->common.hk_cpus = 1;
                        retval = parse_cpu_set(optarg, &params->common.hk_cpu_set);
-                       if (retval) {
-                               err_msg("Error parsing house keeping CPUs\n");
-                               exit(EXIT_FAILURE);
-                       }
+                       if (retval)
+                               fatal("Error parsing house keeping CPUs");
                        break;
                case 'p':
                        params->period = get_llong_from_str(optarg);
@@ -654,10 +650,8 @@ static struct common_params
                case '4': /* trigger */
                        if (params->common.events) {
                                retval = trace_event_add_trigger(params->common.events, optarg);
-                               if (retval) {
-                                       err_msg("Error adding trigger %s\n", optarg);
-                                       exit(EXIT_FAILURE);
-                               }
+                               if (retval)
+                                       fatal("Error adding trigger %s", optarg);
                        } else {
                                osnoise_hist_usage("--trigger requires a previous -e\n");
                        }
@@ -665,10 +659,8 @@ static struct common_params
                case '5': /* filter */
                        if (params->common.events) {
                                retval = trace_event_add_filter(params->common.events, optarg);
-                               if (retval) {
-                                       err_msg("Error adding filter %s\n", optarg);
-                                       exit(EXIT_FAILURE);
-                               }
+                               if (retval)
+                                       fatal("Error adding filter %s", optarg);
                        } else {
                                osnoise_hist_usage("--filter requires a previous -e\n");
                        }
@@ -682,18 +674,14 @@ static struct common_params
                case '8':
                        retval = actions_parse(&params->common.threshold_actions, optarg,
                                               "osnoise_trace.txt");
-                       if (retval) {
-                               err_msg("Invalid action %s\n", optarg);
-                               exit(EXIT_FAILURE);
-                       }
+                       if (retval)
+                               fatal("Invalid action %s", optarg);
                        break;
                case '9':
                        retval = actions_parse(&params->common.end_actions, optarg,
                                               "osnoise_trace.txt");
-                       if (retval) {
-                               err_msg("Invalid action %s\n", optarg);
-                               exit(EXIT_FAILURE);
-                       }
+                       if (retval)
+                               fatal("Invalid action %s", optarg);
                        break;
                default:
                        osnoise_hist_usage("Invalid option");
@@ -703,10 +691,8 @@ static struct common_params
        if (trace_output)
                actions_add_trace_output(&params->common.threshold_actions, trace_output);
 
-       if (geteuid()) {
-               err_msg("rtla needs root permission\n");
-               exit(EXIT_FAILURE);
-       }
+       if (geteuid())
+               fatal("rtla needs root permission");
 
        if (params->common.hist.no_index && !params->common.hist.with_zeros)
                osnoise_hist_usage("no-index set and with-zeros not set - it does not make sense");

diff --git a/tools/tracing/rtla/src/osnoise_top.c b/tools/tracing/rtla/src/osnoise_top.c
index 1b5181e66b175486c9e869ada0b045c1a06c0b07..487daac8908c07e674502e3bc66969d076860166 100644 (file)
--- a/tools/tracing/rtla/src/osnoise_top.c
+++ b/tools/tracing/rtla/src/osnoise_top.c
@@ -421,10 +421,8 @@ struct common_params *osnoise_top_parse_args(int argc, char **argv)
                        break;
                case 'e':
                        tevent = trace_event_alloc(optarg);
-                       if (!tevent) {
-                               err_msg("Error alloc trace event");
-                               exit(EXIT_FAILURE);
-                       }
+                       if (!tevent)
+                               fatal("Error alloc trace event");
 
                        if (params->common.events)
                                tevent->next = params->common.events;
@@ -438,10 +436,8 @@ struct common_params *osnoise_top_parse_args(int argc, char **argv)
                case 'H':
                        params->common.hk_cpus = 1;
                        retval = parse_cpu_set(optarg, &params->common.hk_cpu_set);
-                       if (retval) {
-                               err_msg("Error parsing house keeping CPUs\n");
-                               exit(EXIT_FAILURE);
-                       }
+                       if (retval)
+                               fatal("Error parsing house keeping CPUs");
                        break;
                case 'p':
                        params->period = get_llong_from_str(optarg);
@@ -485,10 +481,8 @@ struct common_params *osnoise_top_parse_args(int argc, char **argv)
                case '0': /* trigger */
                        if (params->common.events) {
                                retval = trace_event_add_trigger(params->common.events, optarg);
-                               if (retval) {
-                                       err_msg("Error adding trigger %s\n", optarg);
-                                       exit(EXIT_FAILURE);
-                               }
+                               if (retval)
+                                       fatal("Error adding trigger %s", optarg);
                        } else {
                                osnoise_top_usage(params, "--trigger requires a previous -e\n");
                        }
@@ -496,10 +490,8 @@ struct common_params *osnoise_top_parse_args(int argc, char **argv)
                case '1': /* filter */
                        if (params->common.events) {
                                retval = trace_event_add_filter(params->common.events, optarg);
-                               if (retval) {
-                                       err_msg("Error adding filter %s\n", optarg);
-                                       exit(EXIT_FAILURE);
-                               }
+                               if (retval)
+                                       fatal("Error adding filter %s", optarg);
                        } else {
                                osnoise_top_usage(params, "--filter requires a previous -e\n");
                        }
@@ -513,18 +505,14 @@ struct common_params *osnoise_top_parse_args(int argc, char **argv)
                case '4':
                        retval = actions_parse(&params->common.threshold_actions, optarg,
                                               "osnoise_trace.txt");
-                       if (retval) {
-                               err_msg("Invalid action %s\n", optarg);
-                               exit(EXIT_FAILURE);
-                       }
+                       if (retval)
+                               fatal("Invalid action %s", optarg);
                        break;
                case '5':
                        retval = actions_parse(&params->common.end_actions, optarg,
                                               "osnoise_trace.txt");
-                       if (retval) {
-                               err_msg("Invalid action %s\n", optarg);
-                               exit(EXIT_FAILURE);
-                       }
+                       if (retval)
+                               fatal("Invalid action %s", optarg);
                        break;
                default:
                        osnoise_top_usage(params, "Invalid option");
@@ -534,10 +522,8 @@ struct common_params *osnoise_top_parse_args(int argc, char **argv)
        if (trace_output)
                actions_add_trace_output(&params->common.threshold_actions, trace_output);
 
-       if (geteuid()) {
-               err_msg("osnoise needs root permission\n");
-               exit(EXIT_FAILURE);
-       }
+       if (geteuid())
+               fatal("osnoise needs root permission");
 
        return &params->common;
 }

diff --git a/tools/tracing/rtla/src/timerlat_hist.c b/tools/tracing/rtla/src/timerlat_hist.c
index c432ef5f59e7feeeea1859ed10c3670f95023f3e..f98deb16b452b2d847a4a71c9303c84f00f548a8 100644 (file)
--- a/tools/tracing/rtla/src/timerlat_hist.c
+++ b/tools/tracing/rtla/src/timerlat_hist.c
@@ -894,10 +894,8 @@ static struct common_params
                        break;
                case 'e':
                        tevent = trace_event_alloc(optarg);
-                       if (!tevent) {
-                               err_msg("Error alloc trace event");
-                               exit(EXIT_FAILURE);
-                       }
+                       if (!tevent)
+                               fatal("Error alloc trace event");
 
                        if (params->common.events)
                                tevent->next = params->common.events;
@@ -917,10 +915,8 @@ static struct common_params
                case 'H':
                        params->common.hk_cpus = 1;
                        retval = parse_cpu_set(optarg, &params->common.hk_cpu_set);
-                       if (retval) {
-                               err_msg("Error parsing house keeping CPUs\n");
-                               exit(EXIT_FAILURE);
-                       }
+                       if (retval)
+                               fatal("Error parsing house keeping CPUs");
                        break;
                case 'i':
                        params->common.stop_us = get_llong_from_str(optarg);
@@ -986,10 +982,8 @@ static struct common_params
                case '6': /* trigger */
                        if (params->common.events) {
                                retval = trace_event_add_trigger(params->common.events, optarg);
-                               if (retval) {
-                                       err_msg("Error adding trigger %s\n", optarg);
-                                       exit(EXIT_FAILURE);
-                               }
+                               if (retval)
+                                       fatal("Error adding trigger %s", optarg);
                        } else {
                                timerlat_hist_usage("--trigger requires a previous -e\n");
                        }
@@ -997,20 +991,16 @@ static struct common_params
                case '7': /* filter */
                        if (params->common.events) {
                                retval = trace_event_add_filter(params->common.events, optarg);
-                               if (retval) {
-                                       err_msg("Error adding filter %s\n", optarg);
-                                       exit(EXIT_FAILURE);
-                               }
+                               if (retval)
+                                       fatal("Error adding filter %s", optarg);
                        } else {
                                timerlat_hist_usage("--filter requires a previous -e\n");
                        }
                        break;
                case '8':
                        params->dma_latency = get_llong_from_str(optarg);
-                       if (params->dma_latency < 0 || params->dma_latency > 10000) {
-                               err_msg("--dma-latency needs to be >= 0 and < 10000");
-                               exit(EXIT_FAILURE);
-                       }
+                       if (params->dma_latency < 0 || params->dma_latency > 10000)
+                               fatal("--dma-latency needs to be >= 0 and < 10000");
                        break;
                case '9':
                        params->no_aa = 1;
@@ -1030,31 +1020,25 @@ static struct common_params
                case '\5':
                        retval = actions_parse(&params->common.threshold_actions, optarg,
                                               "timerlat_trace.txt");
-                       if (retval) {
-                               err_msg("Invalid action %s\n", optarg);
-                               exit(EXIT_FAILURE);
-                       }
+                       if (retval)
+                               fatal("Invalid action %s", optarg);
                        break;
                case '\6':
                        retval = actions_parse(&params->common.end_actions, optarg,
                                               "timerlat_trace.txt");
-                       if (retval) {
-                               err_msg("Invalid action %s\n", optarg);
-                               exit(EXIT_FAILURE);
-                       }
+                       if (retval)
+                               fatal("Invalid action %s", optarg);
                        break;
                default:
-                       timerlat_hist_usage("Invalid option");
+                       fatal("Invalid option");
                }
        }
 
        if (trace_output)
                actions_add_trace_output(&params->common.threshold_actions, trace_output);
 
-       if (geteuid()) {
-               err_msg("rtla needs root permission\n");
-               exit(EXIT_FAILURE);
-       }
+       if (geteuid())
+               fatal("rtla needs root permission");
 
        if (params->common.hist.no_irq && params->common.hist.no_thread)
                timerlat_hist_usage("no-irq and no-thread set, there is nothing to do here");

diff --git a/tools/tracing/rtla/src/timerlat_top.c b/tools/tracing/rtla/src/timerlat_top.c
index 82e227d27af7a847f39018d1102dbcb11b39fbf2..9664b8af727e6d828b73515d7e3f732c6754e3d0 100644 (file)
--- a/tools/tracing/rtla/src/timerlat_top.c
+++ b/tools/tracing/rtla/src/timerlat_top.c
@@ -666,10 +666,8 @@ static struct common_params
                        break;
                case 'e':
                        tevent = trace_event_alloc(optarg);
-                       if (!tevent) {
-                               err_msg("Error alloc trace event");
-                               exit(EXIT_FAILURE);
-                       }
+                       if (!tevent)
+                               fatal("Error alloc trace event");
 
                        if (params->common.events)
                                tevent->next = params->common.events;
@@ -682,10 +680,8 @@ static struct common_params
                case 'H':
                        params->common.hk_cpus = 1;
                        retval = parse_cpu_set(optarg, &params->common.hk_cpu_set);
-                       if (retval) {
-                               err_msg("Error parsing house keeping CPUs\n");
-                               exit(EXIT_FAILURE);
-                       }
+                       if (retval)
+                               fatal("Error parsing house keeping CPUs");
                        break;
                case 'i':
                        params->common.stop_us = get_llong_from_str(optarg);
@@ -736,10 +732,8 @@ static struct common_params
                case '0': /* trigger */
                        if (params->common.events) {
                                retval = trace_event_add_trigger(params->common.events, optarg);
-                               if (retval) {
-                                       err_msg("Error adding trigger %s\n", optarg);
-                                       exit(EXIT_FAILURE);
-                               }
+                               if (retval)
+                                       fatal("Error adding trigger %s", optarg);
                        } else {
                                timerlat_top_usage("--trigger requires a previous -e\n");
                        }
@@ -747,20 +741,16 @@ static struct common_params
                case '1': /* filter */
                        if (params->common.events) {
                                retval = trace_event_add_filter(params->common.events, optarg);
-                               if (retval) {
-                                       err_msg("Error adding filter %s\n", optarg);
-                                       exit(EXIT_FAILURE);
-                               }
+                               if (retval)
+                                       fatal("Error adding filter %s", optarg);
                        } else {
                                timerlat_top_usage("--filter requires a previous -e\n");
                        }
                        break;
                case '2': /* dma-latency */
                        params->dma_latency = get_llong_from_str(optarg);
-                       if (params->dma_latency < 0 || params->dma_latency > 10000) {
-                               err_msg("--dma-latency needs to be >= 0 and < 10000");
-                               exit(EXIT_FAILURE);
-                       }
+                       if (params->dma_latency < 0 || params->dma_latency > 10000)
+                               fatal("--dma-latency needs to be >= 0 and < 10000");
                        break;
                case '3': /* no-aa */
                        params->no_aa = 1;
@@ -780,18 +770,14 @@ static struct common_params
                case '9':
                        retval = actions_parse(&params->common.threshold_actions, optarg,
                                               "timerlat_trace.txt");
-                       if (retval) {
-                               err_msg("Invalid action %s\n", optarg);
-                               exit(EXIT_FAILURE);
-                       }
+                       if (retval)
+                               fatal("Invalid action %s", optarg);
                        break;
                case '\1':
                        retval = actions_parse(&params->common.end_actions, optarg,
                                               "timerlat_trace.txt");
-                       if (retval) {
-                               err_msg("Invalid action %s\n", optarg);
-                               exit(EXIT_FAILURE);
-                       }
+                       if (retval)
+                               fatal("Invalid action %s", optarg);
                        break;
                default:
                        timerlat_top_usage("Invalid option");
@@ -801,10 +787,8 @@ static struct common_params
        if (trace_output)
                actions_add_trace_output(&params->common.threshold_actions, trace_output);
 
-       if (geteuid()) {
-               err_msg("rtla needs root permission\n");
-               exit(EXIT_FAILURE);
-       }
+       if (geteuid())
+               fatal("rtla needs root permission");
 
        /*
         * Auto analysis only happens if stop tracing, thus:

diff --git a/tools/tracing/rtla/src/timerlat_u.c b/tools/tracing/rtla/src/timerlat_u.c
index 01dbf9a6b5a51ed7592e3bed5a6d8d2d26342625..ce68e39d25fdeef892852e036606638096015685 100644 (file)
--- a/tools/tracing/rtla/src/timerlat_u.c
+++ b/tools/tracing/rtla/src/timerlat_u.c
@@ -51,10 +51,8 @@ static int timerlat_u_main(int cpu, struct timerlat_u_params *params)
 
        if (!params->sched_param) {
                retval = sched_setscheduler(0, SCHED_FIFO, &sp);
-               if (retval < 0) {
-                       err_msg("Error setting timerlat u default priority: %s\n", strerror(errno));
-                       exit(1);
-               }
+               if (retval < 0)
+                       fatal("Error setting timerlat u default priority: %s", strerror(errno));
        } else {
                retval = __set_sched_attr(getpid(), params->sched_param);
                if (retval) {
@@ -78,10 +76,8 @@ static int timerlat_u_main(int cpu, struct timerlat_u_params *params)
        snprintf(buffer, sizeof(buffer), "osnoise/per_cpu/cpu%d/timerlat_fd", cpu);
 
        timerlat_fd = tracefs_instance_file_open(NULL, buffer, O_RDONLY);
-       if (timerlat_fd < 0) {
-               err_msg("Error opening %s:%s\n", buffer, strerror(errno));
-               exit(1);
-       }
+       if (timerlat_fd < 0)
+               fatal("Error opening %s:%s", buffer, strerror(errno));
 
        debug_msg("User-space timerlat pid %d on cpu %d\n", gettid(), cpu);
 

diff --git a/tools/tracing/rtla/src/utils.c b/tools/tracing/rtla/src/utils.c
index d6ab15dcb4907e09bcec1c1207adfa5a2655397d..54334c676a2290788dc552f0ca19c64b3a7f470b 100644 (file)
--- a/tools/tracing/rtla/src/utils.c
+++ b/tools/tracing/rtla/src/utils.c
@@ -56,6 +56,21 @@ void debug_msg(const char *fmt, ...)
        fprintf(stderr, "%s", message);
 }
 
+/*
+ * fatal - print an error message and EOL to stderr and exit with ERROR
+ */
+void fatal(const char *fmt, ...)
+{
+       va_list ap;
+
+       va_start(ap, fmt);
+       vfprintf(stderr, fmt, ap);
+       va_end(ap);
+       fprintf(stderr, "\n");
+
+       exit(ERROR);
+}
+
 /*
  * get_llong_from_str - get a long long int from a string
  */

diff --git a/tools/tracing/rtla/src/utils.h b/tools/tracing/rtla/src/utils.h
index a2a6f89f342d09d0c5fcad9d09ea485375f5d5c2..1be095f9a7e6287f057403607707f9e1bb8e9c31 100644 (file)
--- a/tools/tracing/rtla/src/utils.h
+++ b/tools/tracing/rtla/src/utils.h
@@ -19,6 +19,7 @@
 extern int config_debug;
 void debug_msg(const char *fmt, ...);
 void err_msg(const char *fmt, ...);
+void fatal(const char *fmt, ...);
 
 long parse_seconds_duration(char *val);
 void get_duration(time_t start_time, char *output, int output_size);