X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=folly%2Fexperimental%2Fio%2FHugePages.h;h=dcf07e7c06021da1a04cd2f84c5dd943a16542a6;hb=7fda1f29212ba8402e8b43c08e1c66dd1e8e7c95;hp=ef7dcffae79b236b51b75ed74e57ee9d624a6e96;hpb=30be8ac1ced8cb583ed9ac1d894506341e7c77d1;p=folly.git

diff --git a/folly/experimental/io/HugePages.h b/folly/experimental/io/HugePages.h
index ef7dcffa..dcf07e7c 100644
--- a/folly/experimental/io/HugePages.h
+++ b/folly/experimental/io/HugePages.h
@@ -17,8 +17,11 @@
 #ifndef FOLLY_IO_HUGEPAGES_H_
 #define FOLLY_IO_HUGEPAGES_H_
 
+#include <sys/stat.h>
+#include <sys/types.h>
 #include <cstddef>
 #include <string>
+#include <unistd.h>
 #include <utility>
 #include <vector>
 
@@ -30,10 +33,15 @@
 namespace folly {
 
 struct HugePageSize : private boost::totally_ordered<HugePageSize> {
-  HugePageSize() : size(0) { }
   explicit HugePageSize(size_t s) : size(s) { }
-  size_t size;
+
+  fs::path filePath(const fs::path& relpath) const {
+    return mountPoint / relpath;
+  }
+
+  size_t size = 0;
   fs::path mountPoint;
+  dev_t device = 0;
 };
 
 inline bool operator<(const HugePageSize& a, const HugePageSize& b) {
@@ -52,50 +60,23 @@ inline bool operator==(const HugePageSize& a, const HugePageSize& b) {
 typedef std::vector<HugePageSize> HugePageSizeVec;
 
 /**
- * Class to interface with Linux huge pages (hugetlbfs).
+ * Get list of supported huge page sizes and their mount points, if
+ * hugetlbfs file systems are mounted for those sizes.
  */
-class HugePages {
- public:
-  HugePages();
-
-  /**
-   * Get list of supported huge page sizes and their mount points, if
-   * hugetlbfs file systems are mounted for those sizes.
-   */
-  const HugePageSizeVec& sizes() const { return sizes_; }
-
-  /**
-   * Return the mount point for the requested huge page size.
-   * 0 = use smallest available.
-   * Throws on error.
-   */
-  const HugePageSize& getSize(size_t hugePageSize = 0) const;
-
-  /**
-   * Create a file on a huge page filesystem containing a copy of the data
-   * from data.  If multiple huge page sizes are allowed, we
-   * pick the smallest huge page size available, unless you request one
-   * explicitly with the hugePageSize argument.
-   *
-   * The "path" argument must be rooted under the mount point for the
-   * selected huge page size.  If relative, it is considered relative to the
-   * mount point.
-   *
-   * We return a struct File structure containing the full path and size
-   * (rounded up to a multiple of the huge page size)
-   */
-  struct File {
-    File() : size(0) { }
-    fs::path path;
-    size_t size;
-  };
-  File create(
-      ByteRange data, const fs::path& path,
-      HugePageSize hugePageSize = HugePageSize()) const;
-
- private:
-  HugePageSizeVec sizes_;
-};
+const HugePageSizeVec& getHugePageSizes();
+
+/**
+ * Return the mount point for the requested huge page size.
+ * 0 = use smallest available.
+ * Returns nullptr if the requested huge page size is not available.
+ */
+const HugePageSize* getHugePageSize(size_t size = 0);
+
+/**
+ * Return the huge page size for a device.
+ * returns nullptr if device does not refer to a huge page filesystem.
+ */
+const HugePageSize* getHugePageSizeForDevice(dev_t device);
 
 }  // namespace folly