Re: [Intel-gfx] [PATCH i-g-t 1/2] lib/debugfs: Add per GT debugfs helpers

[Dixit, Ashutosh]

On Mon, 27 Mar 2023 19:00:27 -0700, Vinay Belgaumkar wrote:
>
> These can be used to open per-gt debugfs files.
>

Reviewed-by: Ashutosh Dixit 

[Intel-gfx] [PATCH i-g-t 1/2] lib/debugfs: Add per GT debugfs helpers

[Vinay Belgaumkar]

These can be used to open per-gt debugfs files.

Signed-off-by: Tvrtko Ursulin 
Signed-off-by: Vinay Belgaumkar 
---
 lib/igt_debugfs.c | 60 +++
 lib/igt_debugfs.h |  4 
 2 files changed, 64 insertions(+)

diff --git a/lib/igt_debugfs.c b/lib/igt_debugfs.c
index 05889bbe..afde2da6 100644
--- a/lib/igt_debugfs.c
+++ b/lib/igt_debugfs.c
@@ -217,6 +217,37 @@ int igt_debugfs_dir(int device)
return open(path, O_RDONLY);
 }
 
+/**
+ * igt_debugfs_gt_dir:
+ * @device: fd of the device
+ * @gt: GT instance number
+ *
+ * This opens the debugfs directory corresponding to device for use
+ * with igt_sysfs_get() and related functions.
+ *
+ * Returns:
+ * The directory fd, or -1 on failure.
+ */
+int igt_debugfs_gt_dir(int device, unsigned int gt)
+{
+   int debugfs_gt_dir_fd;
+   char path[PATH_MAX];
+   char gtpath[16];
+   int ret;
+
+   if (!igt_debugfs_path(device, path, sizeof(path)))
+   return -1;
+
+   ret = snprintf(gtpath, sizeof(gtpath), "/gt%u", gt);
+   igt_assert(ret < sizeof(gtpath));
+   strncat(path, gtpath, sizeof(path) - 1);
+
+   debugfs_gt_dir_fd = open(path, O_RDONLY);
+   igt_debug_on_f(debugfs_gt_dir_fd < 0, "path: %s\n", path);
+
+   return debugfs_gt_dir_fd;
+}
+
 /**
  * igt_debugfs_connector_dir:
  * @device: fd of the device
@@ -313,6 +344,35 @@ bool igt_debugfs_exists(int device, const char *filename, 
int mode)
return false;
 }
 
+/**
+ * igt_debugfs_gt_open:
+ * @device: open i915 drm fd
+ * @gt: gt instance number
+ * @filename: name of the debugfs node to open
+ * @mode: mode bits as used by open()
+ *
+ * This opens a debugfs file as a Unix file descriptor. The filename should be
+ * relative to the drm device's root, i.e. without "drm/$minor".
+ *
+ * Returns:
+ * The Unix file descriptor for the debugfs file or -1 if that didn't work out.
+ */
+int
+igt_debugfs_gt_open(int device, unsigned int gt, const char *filename, int 
mode)
+{
+   int dir, ret;
+
+   dir = igt_debugfs_gt_dir(device, gt);
+   if (dir < 0)
+   return dir;
+
+   ret = openat(dir, filename, mode);
+
+   close(dir);
+
+   return ret;
+}
+
 /**
  * igt_debugfs_simple_read:
  * @dir: fd of the debugfs directory
diff --git a/lib/igt_debugfs.h b/lib/igt_debugfs.h
index 4824344a..3e6194ad 100644
--- a/lib/igt_debugfs.h
+++ b/lib/igt_debugfs.h
@@ -45,6 +45,10 @@ void __igt_debugfs_write(int fd, const char *filename, const 
char *buf, int size
 int igt_debugfs_simple_read(int dir, const char *filename, char *buf, int 
size);
 bool igt_debugfs_search(int fd, const char *filename, const char *substring);
 
+int igt_debugfs_gt_dir(int device, unsigned int gt);
+int igt_debugfs_gt_open(int device, unsigned int gt, const char *filename,
+   int mode);
+
 /**
  * igt_debugfs_read:
  * @filename: name of the debugfs file
-- 
2.38.1

[Intel-gfx] [PATCH i-g-t 1/2] lib/debugfs: Add per GT debugfs helpers

[Vinay Belgaumkar]

These can be used to open per-gt debugfs files.

Signed-off-by: Tvrtko Ursulin 
Signed-off-by: Vinay Belgaumkar 
---
 lib/igt_debugfs.c | 60 +++
 lib/igt_debugfs.h |  4 
 2 files changed, 64 insertions(+)

diff --git a/lib/igt_debugfs.c b/lib/igt_debugfs.c
index 05889bbe..afde2da6 100644
--- a/lib/igt_debugfs.c
+++ b/lib/igt_debugfs.c
@@ -217,6 +217,37 @@ int igt_debugfs_dir(int device)
return open(path, O_RDONLY);
 }
 
+/**
+ * igt_debugfs_gt_dir:
+ * @device: fd of the device
+ * @gt: GT instance number
+ *
+ * This opens the debugfs directory corresponding to device for use
+ * with igt_sysfs_get() and related functions.
+ *
+ * Returns:
+ * The directory fd, or -1 on failure.
+ */
+int igt_debugfs_gt_dir(int device, unsigned int gt)
+{
+   int debugfs_gt_dir_fd;
+   char path[PATH_MAX];
+   char gtpath[16];
+   int ret;
+
+   if (!igt_debugfs_path(device, path, sizeof(path)))
+   return -1;
+
+   ret = snprintf(gtpath, sizeof(gtpath), "/gt%u", gt);
+   igt_assert(ret < sizeof(gtpath));
+   strncat(path, gtpath, sizeof(path) - 1);
+
+   debugfs_gt_dir_fd = open(path, O_RDONLY);
+   igt_debug_on_f(debugfs_gt_dir_fd < 0, "path: %s\n", path);
+
+   return debugfs_gt_dir_fd;
+}
+
 /**
  * igt_debugfs_connector_dir:
  * @device: fd of the device
@@ -313,6 +344,35 @@ bool igt_debugfs_exists(int device, const char *filename, 
int mode)
return false;
 }
 
+/**
+ * igt_debugfs_gt_open:
+ * @device: open i915 drm fd
+ * @gt: gt instance number
+ * @filename: name of the debugfs node to open
+ * @mode: mode bits as used by open()
+ *
+ * This opens a debugfs file as a Unix file descriptor. The filename should be
+ * relative to the drm device's root, i.e. without "drm/$minor".
+ *
+ * Returns:
+ * The Unix file descriptor for the debugfs file or -1 if that didn't work out.
+ */
+int
+igt_debugfs_gt_open(int device, unsigned int gt, const char *filename, int 
mode)
+{
+   int dir, ret;
+
+   dir = igt_debugfs_gt_dir(device, gt);
+   if (dir < 0)
+   return dir;
+
+   ret = openat(dir, filename, mode);
+
+   close(dir);
+
+   return ret;
+}
+
 /**
  * igt_debugfs_simple_read:
  * @dir: fd of the debugfs directory
diff --git a/lib/igt_debugfs.h b/lib/igt_debugfs.h
index 4824344a..3e6194ad 100644
--- a/lib/igt_debugfs.h
+++ b/lib/igt_debugfs.h
@@ -45,6 +45,10 @@ void __igt_debugfs_write(int fd, const char *filename, const 
char *buf, int size
 int igt_debugfs_simple_read(int dir, const char *filename, char *buf, int 
size);
 bool igt_debugfs_search(int fd, const char *filename, const char *substring);
 
+int igt_debugfs_gt_dir(int device, unsigned int gt);
+int igt_debugfs_gt_open(int device, unsigned int gt, const char *filename,
+   int mode);
+
 /**
  * igt_debugfs_read:
  * @filename: name of the debugfs file
-- 
2.38.1