current changes

allocator/bump_alloc/HugePage/bump_alloc.c

@@ -24,22 +24,81 @@ int count = 0;       /* number of bytes allocated so far*/
 int max = 0;         /* upper limit for count */
 char *buffer = NULL; /* the allocation buffer */
 
-void init_alloc(int size_in_bytes)
+void init_alloc()
 {
-    /* request memory for our allocation buffer
-     * NB mmap min bounds for capability is 1 page (4K)
-     */
-    char *res = mmap(NULL, size_in_bytes, PROT_READ | PROT_WRITE, MAP_ANON | MAP_PRIVATE, -1, 0);
+    // /* request memory for our allocation buffer
+    //  * NB mmap min bounds for capability is 1 page (4K)
+    //  */
+    // char *res = mmap(NULL, size_in_bytes, PROT_READ | PROT_WRITE, MAP_ANON | MAP_PRIVATE, -1, 0);
 
-    if (res == MAP_FAILED)
+    // if (res == MAP_FAILED)
+    // {
+    //     perror("error in initial mem allocation");
+    //     exit(-1);
+    // }
+
+    // buffer = res;
+    // max = size_in_bytes;
+    // return;
+
+     size_t sz;
+   // Pre Allocate 400 MB 
+   sz = 1073741824;
+
+   int error, fd, pscnt, pn;
+
+   size_t ps[MAXPAGESIZES];
+
+   size_t size[3];
+
+   pn = getpagesizes(size, 3);
+   printf("page size is [%d]", size[2]);
+
+   pscnt = pagesizes(ps);
+
+	fd = shm_create_largepage(SHM_ANON, O_CREAT | O_RDWR, 1, SHM_LARGEPAGE_ALLOC_DEFAULT, 0);
+
+   if (fd < 0 && errno == ENOTTY) {
+      perror("sh_create_largepages");
+      close(fd);
+      exit(EXIT_FAILURE);
+   }
+   // if (fd < 0)
+   //     perror("no large page supported");
+   //     exit(EXIT_FAILURE);
+	// if (fd < 0 && errno == ENOTTY)
+	// 	atf_tc_skip("no large page support");
+	// ATF_REQUIRE_MSG(fd >= 0, "shm_create_largepage failed; errno=%d", errno);
+
+	if (ftruncate(fd, sz) < 0) {
+        perror("ftruncate");
+        close(fd);
+        exit(EXIT_FAILURE);
+    }
+	// if (error != 0 && errno == ENOMEM)
+	// 	/*
+	// 	 * The test system might not have enough memory to accommodate
+	// 	 * the request.
+	// 	 */
+	// 	atf_tc_skip("failed to allocate %zu-byte superpage", sz);
+	// ATF_REQUIRE_MSG(error == 0, "ftruncate failed; errno=%d", errno);
+
+   ptr = mmap(NULL, sz,
+    PROT_READ|PROT_WRITE, MAP_SHARED,fd,0);
+
+   // Added error handling
+    if(ptr == MAP_FAILED)
     {
-        perror("error in initial mem allocation");
-        exit(-1);
+        perror("mmap");
+        exit(EXIT_FAILURE);
     }
 
-    buffer = res;
-    max = size_in_bytes;
-    return;
+    buffer = ptr;
+
+    // Hard-coded huge page size
+    max = 1073741824;
+
+    return ptr;
 }
 
 /*