lib: Helper library for parsing i915 fdinfo output

Tests and intel_gpu_top will share common code for parsing this file.

v2:
 * Fix key-value parsing if valid key line ends with ':'.
 * Return number of drm keys found.
 * Add DRM_CLIENT_FDINFO_MAX_ENGINES. (Umesh)
 * Always zero terminate read buffer. (Umesh)

Signed-off-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>

1 files changed, 69 insertions, 0 deletions

diff --git a/lib/igt_drm_fdinfo.h b/lib/igt_drm_fdinfo.h
new file mode 100644
index 00000000..5db63e28
--- /dev/null
+++ b/lib/igt_drm_fdinfo.h
@@ -0,0 +1,69 @@
+/*
+ * Copyright © 2022 Intel Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ *
+ */
+
+#ifndef IGT_DRM_FDINFO_H
+#define IGT_DRM_FDINFO_H
+
+#include <sys/types.h>
+#include <dirent.h>
+#include <stdint.h>
+#include <stdbool.h>
+
+#define DRM_CLIENT_FDINFO_MAX_ENGINES 16
+
+struct drm_client_fdinfo {
+	char driver[128];
+	char pdev[128];
+	unsigned long id;
+
+	unsigned int num_engines;
+	unsigned int capacity[DRM_CLIENT_FDINFO_MAX_ENGINES];
+	uint64_t busy[DRM_CLIENT_FDINFO_MAX_ENGINES];
+};
+
+/**
+ * igt_parse_drm_fdinfo: Parses the drm fdinfo file
+ *
+ * @drm_fd: DRM file descriptor
+ * @info: Structure to populate with read data
+ *
+ * Returns the number of valid drm fdinfo keys found or zero if not all
+ * mandatory keys were present or no engines found.
+ */
+unsigned int igt_parse_drm_fdinfo(int drm_fd, struct drm_client_fdinfo *info);
+
+/**
+ * __igt_parse_drm_fdinfo: Parses the drm fdinfo file
+ *
+ * @dir: File descriptor pointing to /proc/pid/fdinfo directory
+ * @fd: String representation of the file descriptor number to parse.
+ * @info: Structure to populate with read data
+ *
+ * Returns the number of valid drm fdinfo keys found or zero if not all
+ * mandatory keys were present or no engines found.
+ */
+unsigned int __igt_parse_drm_fdinfo(int dir, const char *fd,
+				    struct drm_client_fdinfo *info);
+
+#endif /* IGT_DRM_FDINFO_H */