[igt-dev] [PATCH i-g-t v2] Add support for forcing specific module

Rodrigo Siqueira
2018-09-05T20:38:27Z

This commit adds a new option for forcing the use of a specific driver
indicated via an environment variable.

Changes since V1:
Petri:
- Use an environment variable instead of command line
- Refactor the loop in __search_and_open to accept forced module
- Don't try to load kernel modules

Signed-off-by: Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>
---
lib/drmtest.c | 44 ++++++++++++++++++++++++++++++++++++++++++--
lib/drmtest.h | 2 ++
lib/igt_core.c | 5 +++++
3 files changed, 49 insertions(+), 2 deletions(-)

diff --git a/lib/drmtest.c b/lib/drmtest.c
index bfa2e0f0..6e35d1be 100644
--- a/lib/drmtest.c
+++ b/lib/drmtest.c
@@ -123,6 +123,36 @@ static bool has_known_intel_chipset(int fd)
return true;
}

+static char _forced_driver[5] = "";
+
+/**
+ * __set_forced_driver:
+ * @name: name of driver to forcibly use
+ *
+ * Set the name of a driver to use when calling #drm_open_driver with
+ * the #DRIVER_ANY flag.
+ */
+void __set_forced_driver(const char *name)
+{
+ if (!strcmp(name, "")) {
+ igt_warn("IGT_FORCE_DRIVER flag specified without a value,"
+ "ignoring force option\n");
+ return;
+ }
+
+ igt_info("Attempt to force module %s\n", name);
+
+ strncpy(_forced_driver, name, 4);
+}
+
+static const char *forced_driver(void)
+{
+ if (_forced_driver[0])
+ return _forced_driver;
+
+ return NULL;
+}
+
#define LOCAL_I915_EXEC_VEBOX (4 << 0)
/**
* gem_quiescent_gpu:
@@ -250,8 +280,18 @@ static int __search_and_open(const char *base, int offset, unsigned int chipset)

sprintf(name, "%s%u", base, i + offset);
fd = open_device(name, chipset);
- if (fd != -1)
- return fd;
+ if (fd == -1)
+ continue;
+
+ // Force module
+ if (chipset == DRIVER_ANY && forced_driver()) {
+ if (__is_device(fd, forced_driver()))
+ return fd;
+ close(fd);
+ continue;
+ }
+
+ return fd;
}

return -1;
diff --git a/lib/drmtest.h b/lib/drmtest.h
index 949865ee..62f53ec3 100644
--- a/lib/drmtest.h
+++ b/lib/drmtest.h
@@ -51,6 +51,8 @@
*/
#define DRIVER_ANY ~(DRIVER_VGEM)

+void __set_forced_driver(const char *name);
+
/**
* ARRAY_SIZE:
* @arr: static array
diff --git a/lib/igt_core.c b/lib/igt_core.c
index 23bb858f..8e65b5e3 100644
--- a/lib/igt_core.c
+++ b/lib/igt_core.c
@@ -647,6 +647,11 @@ static void common_init_env(void)
igt_frame_dump_path = getenv("IGT_FRAME_DUMP_PATH");

stderr_needs_sentinel = getenv("IGT_SENTINEL_ON_STDERR") != NULL;
+
+ env = getenv("IGT_FORCE_DRIVER");
+ if (env) {
+ __set_forced_driver(env);
+ }
}

static int common_init(int *argc, char **argv,
--
2.18.0

--
Rodrigo Siqueira
http://siqueira.tech
Graduate Student
Department of Computer Science
University of São Paulo