[igt-dev] [PATCH igt] lib: Dump meminfo and slabinfo if we complain about insufficient memory

[Chris Wilson]

All too frequently, we fail our memory checks to a leak in the driver.
While we give every opportunity for the driver to release the memory
before we fail, if we do dump the meminfo and slabinfo, if available, so
we can assign blame^W^W resolve the problem quickly.

References: https://bugs.freedesktop.org/show_bug.cgi?id=105967
Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
Cc: Martin Peres <martin.peres at linux.intel.com>
Cc: Tomi Sarvela <tomi.p.sarvela at intel.com>
---
 lib/intel_os.c | 28 ++++++++++++++++++++++++++--
 1 file changed, 26 insertions(+), 2 deletions(-)

diff --git a/lib/intel_os.c b/lib/intel_os.c
index bb2c16bf..f0f2872b 100644
--- a/lib/intel_os.c
+++ b/lib/intel_os.c
@@ -51,6 +51,7 @@
 #include "drmtest.h"
 #include "igt_aux.h"
 #include "igt_debugfs.h"
+#include "igt_sysfs.h"
 
 /**
  * intel_get_total_ram_mb:
@@ -280,9 +281,32 @@ int __intel_check_memory(uint64_t count, uint64_t size, unsigned mode,
 void intel_require_memory(uint64_t count, uint64_t size, unsigned mode)
 {
 	uint64_t required, total;
+	bool sufficient_memory;
+
+	sufficient_memory = __intel_check_memory(count, size, mode,
+						 &required, &total);
+	if (!sufficient_memory) {
+		int dir = open("/proc", O_RDONLY);
+		char *info;
+
+		info = igt_sysfs_get(dir, "meminfo");
+		if (info) {
+			igt_debug("Insuffucient free memory; /proc/meminfo:\n%s",
+				  info);
+			free(info);
+		}
+
+		info = igt_sysfs_get(dir, "slabinfo");
+		if (info) {
+			igt_debug("Insuffucient free memory; /proc/slabinfo:\n%s",
+				  info);
+			free(info);
+		}
+
+		close(dir);
+	}
 
-	igt_require_f(__intel_check_memory(count, size, mode,
-					    &required, &total),
+	igt_require_f(sufficient_memory,
 		      "Estimated that we need %'llu objects and %'llu MiB for the test, but only have %'llu MiB available (%s%s) and a maximum of %'llu objects\n",
 		      (long long)count,
 		      (long long)((required + ((1<<20) - 1)) >> 20),
-- 
2.17.0