[igt-dev] [PATCH i-g-t] lib/igt_sysfs: Add helpers to iterate over GTs

[igt-dev] [PATCH i-g-t] lib/igt_sysfs: Add helpers to iterate over GTs

[priyanka.dandamudi]

From: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>

Provide iterators to:
- construct the subdirectory string for a gt
- obtain fd for the subdirectory of the interface

v2: Separated out RPS functionality into seaparate patch (Ashutosh)

v3: Minute modifications. (Priyanka)

Cc: Kamil Konieczny <kamil.konieczny@linux.intel.com>
Cc: Andi Shyti <andi.shyti@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Sujaritha Sundaresan <sujaritha.sundaresan@intel.com>
Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: Priyanka Dandamudi <priyanka.dandamudi@intel.com>
Reviewed-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
---
 lib/igt_sysfs.c | 71 +++++++++++++++++++++++++++++++++++++++++++++++++
 lib/igt_sysfs.h | 13 +++++++++
 2 files changed, 84 insertions(+)

diff --git a/lib/igt_sysfs.c b/lib/igt_sysfs.c
index f8ef23e2..4ea93e05 100644
--- a/lib/igt_sysfs.c
+++ b/lib/igt_sysfs.c
@@ -54,6 +54,21 @@
  * provides basic support for like igt_sysfs_open().
  */
 
+/**
+ * igt_sysfs_has_attr:
+ * @dir: sysfs directory fd
+ * @attr: attr inside sysfs dir that needs to be checked for existence
+ *
+ * This checks if specified attr exists in device sysfs directory.
+ *
+ * Returns:
+ * true if attr exists in sysfs, false otherwise.
+ */
+bool igt_sysfs_has_attr(int dir, const char *attr)
+{
+	return !faccessat(dir, attr, F_OK, 0);
+}
+
 /**
  * igt_sysfs_path:
  * @device: fd of the device
@@ -104,6 +119,62 @@ int igt_sysfs_open(int device)
 	return open(path, O_RDONLY);
 }
 
+/**
+ * igt_sysfs_gt_path:
+ * @device: fd of the device
+ * @gt: gt number
+ * @path: buffer to fill with the sysfs gt path to the device
+ * @pathlen: length of @path buffer
+ *
+ * This finds the sysfs directory corresponding to @device and @gt. If the gt
+ * specific directory is not available and gt is 0, path is filled with sysfs
+ * base directory.
+ *
+ * Returns:
+ * The directory path, or NULL on failure.
+ */
+char *igt_sysfs_gt_path(int device, int gt, char *path, int pathlen)
+{
+	struct stat st;
+
+	if (device < 0)
+		return NULL;
+
+	if (igt_debug_on(fstat(device, &st)) || igt_debug_on(!S_ISCHR(st.st_mode)))
+		return NULL;
+
+	snprintf(path, pathlen, "/sys/dev/char/%d:%d/gt/gt%d",
+		 major(st.st_rdev), minor(st.st_rdev), gt);
+
+	if (!access(path, F_OK))
+		return path;
+	else if (!gt)
+		return igt_sysfs_path(device, path, pathlen);
+
+	return NULL;
+}
+
+/**
+ * igt_sysfs_gt_open:
+ * @device: fd of the device
+ * @gt: gt number
+ *
+ * This opens the sysfs gt directory corresponding to device and gt for use
+ * with igt_sysfs_set() and igt_sysfs_get().
+ *
+ * Returns:
+ * The directory fd, or -1 on failure.
+ */
+int igt_sysfs_gt_open(int device, int gt)
+{
+	char path[96];
+
+	if (igt_debug_on(!igt_sysfs_gt_path(device, gt, path, sizeof(path))))
+		return -1;
+
+	return open(path, O_RDONLY);
+}
+
 /**
  * igt_sysfs_write:
  * @dir: directory for the device from igt_sysfs_open()
diff --git a/lib/igt_sysfs.h b/lib/igt_sysfs.h
index 56741a0a..33317a96 100644
--- a/lib/igt_sysfs.h
+++ b/lib/igt_sysfs.h
@@ -28,8 +28,21 @@
 #include <stdbool.h>
 #include <stdarg.h>
 
+#define for_each_sysfs_gt_path(i915__, path__, pathlen__) \
+	for (int gt__ = 0; \
+	     igt_sysfs_gt_path(i915__, gt__, path__, pathlen__) != NULL; \
+	     gt__++)
+
+#define for_each_sysfs_gt_dirfd(i915__, dirfd__, gt__) \
+	for (gt__ = 0; \
+	     (dirfd__ = igt_sysfs_gt_open(i915__, gt__)) != -1; \
+	     close(dirfd__), gt__++)
+
 char *igt_sysfs_path(int device, char *path, int pathlen);
 int igt_sysfs_open(int device);
+char *igt_sysfs_gt_path(int device, int gt, char *path, int pathlen);
+int igt_sysfs_gt_open(int device, int gt);
+bool igt_sysfs_has_attr(int dir, const char *attr);
 
 int igt_sysfs_read(int dir, const char *attr, void *data, int len);
 int igt_sysfs_write(int dir, const char *attr, const void *data, int len);
-- 
2.25.1

[igt-dev] ✗ Fi.CI.BUILD: failure for lib/igt_sysfs: Add helpers to iterate over GTs

[Patchwork]

== Series Details ==

Series: lib/igt_sysfs: Add helpers to iterate over GTs
URL   : https://patchwork.freedesktop.org/series/103152/
State : failure

== Summary ==

Applying: lib/igt_sysfs: Add helpers to iterate over GTs
Using index info to reconstruct a base tree...
M	lib/igt_sysfs.c
M	lib/igt_sysfs.h
Falling back to patching base and 3-way merge...
Auto-merging lib/igt_sysfs.h
CONFLICT (content): Merge conflict in lib/igt_sysfs.h
Auto-merging lib/igt_sysfs.c
CONFLICT (content): Merge conflict in lib/igt_sysfs.c
Patch failed at 0001 lib/igt_sysfs: Add helpers to iterate over GTs
When you have resolved this problem, run "git am --continue".
If you prefer to skip this patch, run "git am --skip" instead.
To restore the original branch and stop patching, run "git am --abort".

Re: [igt-dev] [PATCH i-g-t] lib/igt_sysfs: Add helpers to iterate over GTs

[Kamil Konieczny]

Hi Priyanka,

one more nit, see below.

On 2022-04-26 at 20:34:15 +0530, priyanka.dandamudi@intel.com wrote:
> From: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
> 
> Provide iterators to:
> - construct the subdirectory string for a gt
> - obtain fd for the subdirectory of the interface
> 
> v2: Separated out RPS functionality into seaparate patch (Ashutosh)
> 
> v3: Minute modifications. (Priyanka)
> 
> Cc: Kamil Konieczny <kamil.konieczny@linux.intel.com>
> Cc: Andi Shyti <andi.shyti@intel.com>
> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
> Cc: Sujaritha Sundaresan <sujaritha.sundaresan@intel.com>
> Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@intel.com>
> Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
> Signed-off-by: Priyanka Dandamudi <priyanka.dandamudi@intel.com>
> Reviewed-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
> ---
>  lib/igt_sysfs.c | 71 +++++++++++++++++++++++++++++++++++++++++++++++++
>  lib/igt_sysfs.h | 13 +++++++++
>  2 files changed, 84 insertions(+)
> 
> diff --git a/lib/igt_sysfs.c b/lib/igt_sysfs.c
> index f8ef23e2..4ea93e05 100644
> --- a/lib/igt_sysfs.c
> +++ b/lib/igt_sysfs.c
> @@ -54,6 +54,21 @@
>   * provides basic support for like igt_sysfs_open().
>   */
>  
> +/**
> + * igt_sysfs_has_attr:
> + * @dir: sysfs directory fd
> + * @attr: attr inside sysfs dir that needs to be checked for existence
> + *
> + * This checks if specified attr exists in device sysfs directory.
> + *
> + * Returns:
> + * true if attr exists in sysfs, false otherwise.
> + */
> +bool igt_sysfs_has_attr(int dir, const char *attr)
> +{
> +	return !faccessat(dir, attr, F_OK, 0);
> +}
> +
>  /**
>   * igt_sysfs_path:
>   * @device: fd of the device
> @@ -104,6 +119,62 @@ int igt_sysfs_open(int device)
>  	return open(path, O_RDONLY);
>  }
>  
> +/**
> + * igt_sysfs_gt_path:
> + * @device: fd of the device
> + * @gt: gt number
> + * @path: buffer to fill with the sysfs gt path to the device
> + * @pathlen: length of @path buffer
> + *
> + * This finds the sysfs directory corresponding to @device and @gt. If the gt
> + * specific directory is not available and gt is 0, path is filled with sysfs
> + * base directory.
> + *
> + * Returns:
> + * The directory path, or NULL on failure.
> + */
> +char *igt_sysfs_gt_path(int device, int gt, char *path, int pathlen)
> +{
> +	struct stat st;
> +
> +	if (device < 0)
> +		return NULL;
> +
> +	if (igt_debug_on(fstat(device, &st)) || igt_debug_on(!S_ISCHR(st.st_mode)))
> +		return NULL;
> +
> +	snprintf(path, pathlen, "/sys/dev/char/%d:%d/gt/gt%d",
> +		 major(st.st_rdev), minor(st.st_rdev), gt);
> +
> +	if (!access(path, F_OK))
> +		return path;
> +	else if (!gt)
> +		return igt_sysfs_path(device, path, pathlen);
> +
> +	return NULL;
> +}
> +
> +/**
> + * igt_sysfs_gt_open:
> + * @device: fd of the device
> + * @gt: gt number
> + *
> + * This opens the sysfs gt directory corresponding to device and gt for use
> + * with igt_sysfs_set() and igt_sysfs_get().
> + *
> + * Returns:
> + * The directory fd, or -1 on failure.
> + */
> +int igt_sysfs_gt_open(int device, int gt)
> +{
> +	char path[96];
> +
> +	if (igt_debug_on(!igt_sysfs_gt_path(device, gt, path, sizeof(path))))
----------- ^
imho here we should not use igt_debug_on because we use this
function in iterator macro for_each_sysfs_gt_dirfd and the end
condition is hitting end of available GTs and returning -1.

Regards,
Kamil

> +		return -1;
> +
> +	return open(path, O_RDONLY);
> +}
> +
>  /**
>   * igt_sysfs_write:
>   * @dir: directory for the device from igt_sysfs_open()
> diff --git a/lib/igt_sysfs.h b/lib/igt_sysfs.h
> index 56741a0a..33317a96 100644
> --- a/lib/igt_sysfs.h
> +++ b/lib/igt_sysfs.h
> @@ -28,8 +28,21 @@
>  #include <stdbool.h>
>  #include <stdarg.h>
>  
> +#define for_each_sysfs_gt_path(i915__, path__, pathlen__) \
> +	for (int gt__ = 0; \
> +	     igt_sysfs_gt_path(i915__, gt__, path__, pathlen__) != NULL; \
> +	     gt__++)
> +
> +#define for_each_sysfs_gt_dirfd(i915__, dirfd__, gt__) \
> +	for (gt__ = 0; \
> +	     (dirfd__ = igt_sysfs_gt_open(i915__, gt__)) != -1; \
> +	     close(dirfd__), gt__++)
> +
>  char *igt_sysfs_path(int device, char *path, int pathlen);
>  int igt_sysfs_open(int device);
> +char *igt_sysfs_gt_path(int device, int gt, char *path, int pathlen);
> +int igt_sysfs_gt_open(int device, int gt);
> +bool igt_sysfs_has_attr(int dir, const char *attr);
>  
>  int igt_sysfs_read(int dir, const char *attr, void *data, int len);
>  int igt_sysfs_write(int dir, const char *attr, const void *data, int len);
> -- 
> 2.25.1
> 

Re: [igt-dev] [PATCH i-g-t] lib/igt_sysfs: Add helpers to iterate over GTs

[Dixit, Ashutosh]

On Wed, 27 Apr 2022 04:38:54 -0700, Kamil Konieczny wrote:
>
> > +/**
> > + * igt_sysfs_gt_open:
> > + * @device: fd of the device
> > + * @gt: gt number
> > + *
> > + * This opens the sysfs gt directory corresponding to device and gt for use
> > + * with igt_sysfs_set() and igt_sysfs_get().
> > + *
> > + * Returns:
> > + * The directory fd, or -1 on failure.
> > + */
> > +int igt_sysfs_gt_open(int device, int gt)
> > +{
> > +	char path[96];
> > +
> > +	if (igt_debug_on(!igt_sysfs_gt_path(device, gt, path, sizeof(path))))
> ----------- ^
> imho here we should not use igt_debug_on because we use this
> function in iterator macro for_each_sysfs_gt_dirfd and the end
> condition is hitting end of available GTs and returning -1.

Hi Kamil,

You are right, I removed other igt_debug_on's and merged it but missed this
one. Somebody will need to send a patch for this. Sorry about that.

Thanks.
--
Ashutosh