From 791fff95c3acf11bddad67bcbcf641c22f39f5e2 Mon Sep 17 00:00:00 2001
From: Damien Lespiau <damien.lespiau@intel.com>
Date: Fri, 21 Jan 2011 11:01:24 +0000
Subject: [PATCH] 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.
---
 collector.c   |  8 +++++---
 collector.h   |  1 +
 sysprof-cli.c | 27 +++++++++++++++++++++++----
 sysprof.c     |  2 +-
 4 files changed, 30 insertions(+), 8 deletions(-)

diff --git a/collector.c b/collector.c
index 86d96ed0..b28964fd 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 3c0c1181..2689a597 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 90f5b13e..e8d26ee2 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 55f1b09b..20d3d2c4 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);