[PATCH 03/22] drm/i915/gemfs: enable THP

Matthew Auld
2017-08-15T18:16:56Z

Enable transparent-huge-pages through gemfs by mounting with
huge=within_size.

Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
---
drivers/gpu/drm/i915/i915_gemfs.c | 15 +++++++++++++++
1 file changed, 15 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_gemfs.c b/drivers/gpu/drm/i915/i915_gemfs.c
index 168d0bd98f60..999f0b6a2d64 100644
--- a/drivers/gpu/drm/i915/i915_gemfs.c
+++ b/drivers/gpu/drm/i915/i915_gemfs.c
@@ -24,6 +24,7 @@

#include <linux/fs.h>
#include <linux/mount.h>
+#include <linux/pagemap.h>

#include "i915_drv.h"
#include "i915_gemfs.h"
@@ -41,6 +42,20 @@ int i915_gemfs_init(struct drm_i915_private *i915)
if (IS_ERR(gemfs))
return PTR_ERR(gemfs);

+ if (has_transparent_hugepage()) {
+ struct super_block *sb = gemfs->mnt_sb;
+ char options[] = "huge=within_size";
+ int flags = 0;
+
+ /* We don't consider failure to remount fatal, since this should
+ * only ever attempt to modify the mount options of the sb, and
+ * so should always leave us with a working mount upon failure.
+ * Hence decoupling this from the actual kern_mount is probably
+ * advisable.
+ */
+ WARN_ON(sb->s_op->remount_fs(sb, &flags, options));
+ }
+
i915->mm.gemfs = gemfs;

return 0;