lib: Use safe wrappers around libpciaccess initialization functions

Multiple calls to igt functions using pci_system_init() provided by
libpciaccess result in memory leaking if not followed by its counterpart
pci_system_cleanup() before next use.  On the other hand, calling
pci_system_cleanup() can affect other users which still depend on global
data initialized by pci_system_init().

Introduce safe IGT wrappers around those libpciaccess functions and use
those wrappers in IGT library and tests.

Signed-off-by: Janusz Krzysztofik <janusz.krzysztofik@linux.intel.com>
[jkrzyszt: shorten excessive long name of hidden variable (Chris)]
Reviewed-by: Chris Wilson <chris.p.wilson@intel.com>

1 files changed, 20 insertions, 0 deletions

diff --git a/lib/igt_core.c b/lib/igt_core.c
index ab27a24d..f2c701de 100644
--- a/lib/igt_core.c
+++ b/lib/igt_core.c
@@ -3070,3 +3070,23 @@ err:
 
 	return -1;
 }
+
+/* IGT wrappers around libpciaccess init/cleanup functions */
+
+static void pci_system_exit_handler(int sig)
+{
+	pci_system_cleanup();
+}
+
+static void __pci_system_init(void)
+{
+	if (!igt_warn_on_f(pci_system_init(), "Could not initialize libpciaccess global data\n"))
+		igt_install_exit_handler(pci_system_exit_handler);
+}
+
+int igt_pci_system_init(void)
+{
+	static pthread_once_t once_control = PTHREAD_ONCE_INIT;
+
+	return pthread_once(&once_control, __pci_system_init);
+}