[igt-dev] [PATCH i-g-t 3/3] lib: Enable extra kernel logs for audio debug

[Ashutosh Dixit]

For debug of audio issues in power management and driver reload tests,
additional kernel logs may be useful, both in dmesg as well as
ftrace. Add the infrastructure to generate these logs and enable these
logs for selected tests.

At present igt_runner and other CI infrastructure does not capture the
ftrace buffer. Therefore, to avoid changes to igt_runner and the CI
infrastructure the ftrace buffer is dumped to stdout at the end of
each test.

v4: remove system() calls, dump audio kernel logs from igt_fixture
v2, v3: versions to fix CI

Cc: Jani Nikula <jani.nikula at linux.intel.com>
Signed-off-by: Ashutosh Dixit <ashutosh.dixit at intel.com>
---
 lib/igt_audio.c               | 40 +++++++++++++++++++++++++++++++++++
 lib/igt_audio.h               |  2 ++
 tests/i915/i915_module_load.c |  8 +++++++
 tests/i915/i915_pm_rpm.c      |  8 ++++++-
 tests/i915/i915_suspend.c     |  8 +++++--
 5 files changed, 63 insertions(+), 3 deletions(-)

diff --git a/lib/igt_audio.c b/lib/igt_audio.c
index a0592d53..8a7841be 100644
--- a/lib/igt_audio.c
+++ b/lib/igt_audio.c
@@ -31,6 +31,8 @@
 
 #include "igt_audio.h"
 #include "igt_core.h"
+#include "igt_debugfs.h"
+#include "igt_ftrace.h"
 
 #define FREQS_MAX	8
 
@@ -323,3 +325,41 @@ bool audio_signal_detect(struct audio_signal *signal, int channels,
 
 	return true;
 }
+
+static const char *audio_dmesg_en[] = {
+	"file sound/* +p",
+};
+
+static const char *audio_dmesg_dis[] = {
+	"file sound/* -p",
+};
+
+static const char *audio_ftr[] = {
+	"events/sst/enable",
+	"events/intel-sst/enable",
+	"events/asoc/enable",
+	"events/i2c/enable",
+	"events/hda/enable",
+	"events/hda_controller/enable",
+	"events/hda_intel/enable",
+};
+
+void igt_enable_audio_klog(void)
+{
+	igt_set_dynamic_debug(audio_dmesg_en,
+			      sizeof(audio_dmesg_en)/sizeof(char*));
+	igt_ftrace_set_events(audio_ftr,
+			      sizeof(audio_ftr)/sizeof(char*), true);
+	__igt_ftrace_enable("nop", NULL);
+}
+
+void igt_disable_audio_klog(void)
+{
+	igt_ftrace_disable();
+	igt_ftrace_set_events(audio_ftr,
+			      sizeof(audio_ftr)/sizeof(char*), false);
+	igt_ftrace_dump("Ftrace output");
+	igt_ftrace_clear();
+	igt_set_dynamic_debug(audio_dmesg_dis,
+			      sizeof(audio_dmesg_dis)/sizeof(char*));
+}
diff --git a/lib/igt_audio.h b/lib/igt_audio.h
index b3b658a4..dab5ab5a 100644
--- a/lib/igt_audio.h
+++ b/lib/igt_audio.h
@@ -40,5 +40,7 @@ void audio_signal_clean(struct audio_signal *signal);
 void audio_signal_fill(struct audio_signal *signal, short *buffer, int frames);
 bool audio_signal_detect(struct audio_signal *signal, int channels,
 			 int sampling_rate, short *buffer, int frames);
+void igt_enable_audio_klog(void);
+void igt_disable_audio_klog(void);
 
 #endif
diff --git a/tests/i915/i915_module_load.c b/tests/i915/i915_module_load.c
index 7fe83520..0d569a55 100644
--- a/tests/i915/i915_module_load.c
+++ b/tests/i915/i915_module_load.c
@@ -326,6 +326,10 @@ hda_dynamic_debug(bool enable)
 
 igt_main
 {
+	igt_fixture {
+		igt_enable_audio_klog();
+	}
+
 	igt_subtest("reload") {
 		int load_error;
 
@@ -365,5 +369,9 @@ igt_main
 		/* inject_fault() leaves the module unloaded */
 	}
 
+	igt_fixture {
+		igt_disable_audio_klog();
+	}
+
 	/* Subtests should unload the module themselves if they use modparams */
 }
diff --git a/tests/i915/i915_pm_rpm.c b/tests/i915/i915_pm_rpm.c
index 03de609c..126d68ac 100644
--- a/tests/i915/i915_pm_rpm.c
+++ b/tests/i915/i915_pm_rpm.c
@@ -1975,8 +1975,10 @@ int main(int argc, char *argv[])
 	/* Skip instead of failing in case the machine is not prepared to reach
 	 * PC8+. We don't want bug reports from cases where the machine is just
 	 * not properly configured. */
-	igt_fixture
+	igt_fixture {
+		igt_enable_audio_klog();
 		igt_require(setup_environment());
+	}
 
 	if (stay)
 		igt_subtest("stay")
@@ -2118,5 +2120,9 @@ int main(int argc, char *argv[])
 		igt_i915_driver_unload();
 	}
 
+	igt_fixture {
+		igt_disable_audio_klog();
+	}
+
 	igt_exit();
 }
diff --git a/tests/i915/i915_suspend.c b/tests/i915/i915_suspend.c
index 17c68cc1..527e974e 100644
--- a/tests/i915/i915_suspend.c
+++ b/tests/i915/i915_suspend.c
@@ -207,8 +207,10 @@ igt_main
 {
 	igt_skip_on_simulation();
 
-	igt_fixture
+	igt_fixture {
 		fd = drm_open_driver(DRIVER_INTEL);
+		igt_enable_audio_klog();
+	}
 
 	igt_subtest("fence-restore-tiled2untiled")
 		test_fence_restore(fd, true, false);
@@ -243,6 +245,8 @@ igt_main
 	igt_subtest("forcewake-hibernate")
 		test_forcewake(fd, true);
 
-	igt_fixture
+	igt_fixture {
+		igt_disable_audio_klog();
 		close(fd);
+	}
 }
-- 
2.21.0