cli: Allow to get samples from single pid

perf lets you decide to only get events that concerns a single process
and thus make sysprof profile this process instead of the whole system
(it can happen that you don't really care about other processes that are
just then noise).

As a side effect, this allows sysprof to not run as root if you have the
rights on the process you want to profile.

4 files changed, 30 insertions, 8 deletions

diff --git a/collector.c b/collector.c
index 86d96ed..b28964f 100644
--- a/collector.c
+++ b/collector.c
@@ -401,6 +401,7 @@ counter_disable (counter_t *counter)
 
 static counter_t *
 counter_new (Collector  *collector,
+	     pid_t	 pid,
 	     int	 cpu,
 	     counter_t  *output,
 	     GError    **err)
@@ -427,13 +428,13 @@ counter_new (Collector  *collector,
     attr.task = 1;
     attr.exclude_idle = 1;
     
-    if (!collector->use_hw_counters || (fd = sysprof_perf_counter_open (&attr, -1, cpu, -1,  0)) < 0)
+    if (!collector->use_hw_counters || (fd = sysprof_perf_counter_open (&attr, pid, cpu, -1,  0)) < 0)
     {
 	attr.type = PERF_TYPE_SOFTWARE;
 	attr.config = PERF_COUNT_SW_CPU_CLOCK;
 	attr.sample_period = 1000000;
 	
-	fd = sysprof_perf_counter_open (&attr, -1, cpu, -1, 0);
+	fd = sysprof_perf_counter_open (&attr, pid, cpu, -1, 0);
     }
     
     if (fd < 0)
@@ -717,6 +718,7 @@ process_event (Collector       *collector,
 
 gboolean
 collector_start (Collector  *collector,
+		 pid_t       pid,
 		 GError    **err)
 {
     int n_cpus = get_n_cpus ();
@@ -729,7 +731,7 @@ collector_start (Collector  *collector,
     output = NULL;
     for (i = 0; i < n_cpus; ++i)
     {
-	counter_t *counter = counter_new (collector, i, output, err);
+	counter_t *counter = counter_new (collector, pid, i, output, err);
 
 	if (!counter)
 	{
diff --git a/collector.h b/collector.h
index 3c0c118..2689a59 100644
--- a/collector.h
+++ b/collector.h
@@ -38,6 +38,7 @@ Collector *collector_new            (gboolean        use_hw_counters,
 				     CollectorFunc   callback,
 				     gpointer        data);
 gboolean   collector_start          (Collector      *collector,
+				     pid_t           pid,
 				     GError        **err);
 void       collector_stop           (Collector      *collector);
 void       collector_reset          (Collector      *collector);
diff --git a/sysprof-cli.c b/sysprof-cli.c
index 90f5b13..e8d26ee 100644
--- a/sysprof-cli.c
+++ b/sysprof-cli.c
@@ -111,19 +111,38 @@ die (const char *err_msg)
     exit (-1);
 }
 
+static int opt_pid = -1;
+
+static GOptionEntry entries[] =
+{
+  { "pid", 'p', 0, G_OPTION_ARG_INT, &opt_pid,
+    "Make sysprof specific to a task", NULL },
+  { NULL }
+};
+
 int
 main (int argc, char *argv[])
 {
-    Application *app = g_new0 (Application, 1);
+    Application *app;
+    GOptionContext *context;
     GError *err;
     
+    err = NULL;
+
+    context = g_option_context_new ("- Sysprof");
+    g_option_context_add_main_entries (context, entries, NULL);
+    if (!g_option_context_parse (context, &argc, &argv, &err))
+    {
+	    g_print ("Failed to parse options: %s\n", err->message);
+	    return 1;
+    }
+
+    app = g_new0 (Application, 1);
     app->collector = collector_new (FALSE, NULL, NULL);
     app->outfile = g_strdup (argv[1]);
     app->main_loop = g_main_loop_new (NULL, 0);
     
-    err = NULL;
-    
-    if (!collector_start (app->collector, &err))
+    if (!collector_start (app->collector, (pid_t) opt_pid, &err))
 	die (err->message);
     
     if (argc < 2)
diff --git a/sysprof.c b/sysprof.c
index 55f1b09..20d3d2c 100644
--- a/sysprof.c
+++ b/sysprof.c
@@ -365,7 +365,7 @@ on_start_toggled (GtkWidget *widget, gpointer data)
 	return;
     }
 
-    if (collector_start (app->collector, &err))
+    if (collector_start (app->collector, -1, &err))
     {
 	delete_data (app);