perf daemon: Add config option

Add a config option and base functionality that takes the option
argument (if specified) and other system config locations and produces
an 'acting' config file path.

The actual config file processing is coming in following patches.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Budankov <abudankov@huawei.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: https://lore.kernel.org/r/20210208200908.1019149-3-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

diff --git a/tools/perf/Documentation/perf-daemon.txt b/tools/perf/Documentation/perf-daemon.txt
index d05b8dab0a6ad0a20390b0a07aa574421c5a45cd..ba3f88510aee10eecc0f2aed0243d215aef99b9e 100644 (file)
--- a/tools/perf/Documentation/perf-daemon.txt
+++ b/tools/perf/Documentation/perf-daemon.txt
@@ -27,6 +27,10 @@ OPTIONS
 --verbose::
        Be more verbose.
 
+--config=<PATH>::
+       Config file path. If not provided, perf will check system and default
+       locations (/etc/perfconfig, $HOME/.perfconfig).
+
 All generic options are available also under commands.
 
 

diff --git a/tools/perf/builtin-daemon.c b/tools/perf/builtin-daemon.c
index 8b13e455ac40cb42f8661386e9361263edebb58d..90b5a8ea9ddaeb35833d17581eed91d8e0de4312 100644 (file)
--- a/tools/perf/builtin-daemon.c
+++ b/tools/perf/builtin-daemon.c
@@ -3,14 +3,18 @@
 #include <linux/limits.h>
 #include <string.h>
 #include <signal.h>
+#include <stdlib.h>
 #include <stdio.h>
 #include <unistd.h>
 #include "builtin.h"
 #include "perf.h"
 #include "debug.h"
+#include "config.h"
 #include "util.h"
 
 struct daemon {
+       const char              *config;
+       char                    *config_real;
        char                    *base;
        FILE                    *out;
        char                     perf[PATH_MAX];
@@ -31,6 +35,32 @@ static void sig_handler(int sig __maybe_unused)
        done = true;
 }
 
+static void daemon__exit(struct daemon *daemon)
+{
+       free(daemon->config_real);
+}
+
+static int setup_config(struct daemon *daemon)
+{
+       if (daemon->config) {
+               char *real = realpath(daemon->config, NULL);
+
+               if (!real) {
+                       perror("failed: realpath");
+                       return -1;
+               }
+               daemon->config_real = real;
+               return 0;
+       }
+
+       if (perf_config_system() && !access(perf_etc_perfconfig(), R_OK))
+               daemon->config_real = strdup(perf_etc_perfconfig());
+       else if (perf_config_global() && perf_home_perfconfig())
+               daemon->config_real = strdup(perf_home_perfconfig());
+
+       return daemon->config_real ? 0 : -1;
+}
+
 static int __cmd_start(struct daemon *daemon, struct option parent_options[],
                       int argc, const char **argv)
 {
@@ -44,6 +74,11 @@ static int __cmd_start(struct daemon *daemon, struct option parent_options[],
        if (argc)
                usage_with_options(daemon_usage, start_options);
 
+       if (setup_config(daemon)) {
+               pr_err("failed: config not found\n");
+               return -1;
+       }
+
        debug_set_file(daemon->out);
        debug_set_display_time(true);
 
@@ -56,6 +91,8 @@ static int __cmd_start(struct daemon *daemon, struct option parent_options[],
                sleep(1);
        }
 
+       daemon__exit(daemon);
+
        pr_info("daemon exited\n");
        fclose(daemon->out);
        return err;
@@ -65,6 +102,8 @@ int cmd_daemon(int argc, const char **argv)
 {
        struct option daemon_options[] = {
                OPT_INCR('v', "verbose", &verbose, "be more verbose"),
+               OPT_STRING(0, "config", &__daemon.config,
+                       "config file", "config file path"),
                OPT_END()
        };
 
@@ -82,5 +121,10 @@ int cmd_daemon(int argc, const char **argv)
                return -1;
        }
 
+       if (setup_config(&__daemon)) {
+               pr_err("failed: config not found\n");
+               return -1;
+       }
+
        return -1;
 }