pmm: Added NBBS definitions and init() function. WIP.

Signed-off-by: TunaCici <[email protected]>

Kernel/Include/Memory/NBBS.h

@@ -0,0 +1,82 @@
+/*
+ * Non-Blocking Buddy System - To be used to the new physical memory mngr.
+ *
+ * As described in:
+ * "A Non-blocking Buddy System for Scalable Memory Allocation on Multi-core 
+ * Machines by" R. Marotta, M. Ianni, A. Scarselli, A. Pellegrini and F. Quaglia
+ *
+ * Reference:
+ * https://github.com/HPDCS/NBBS
+ *
+ * Author: Tuna CICI
+ */
+
+#include <stdint.h>
+
+/*
+ * Tree node status bits:
+ *
+ *  7       5          4            3            2          1          0
+ * +---------+----------+------------+------------+----------+----------+
+ * | ignored | occupied |    left    |    rigth   |   left   |   right  |
+ * |         |          | coalescent | coalescent | occupied | occupied |
+ * +---------+----------+------------+------------+----------+----------+
+ */
+
+#define OCC_RIGHT       0x1
+#define OCC_LEFT        0x2
+#define COAL_RIGHT      0x4
+#define COAL_LEFT       0x8
+#define OCC             0x10
+#define BUSY            (OCC | OCC_LEFT | OCC_RIGHT)
+
+/*
+ * Public APIs
+ *
+ * TODO: Explain.
+ */
+
+int  nb_init(uint64_t base_addr, uint64_t size);
+void* nb_alloc(uint64_t size);
+void* nb_free(void *addr);
+
+/*
+ * Helpers
+ *
+ * TODO:? Explain.
+ */
+
+static inline uint8_t clean_coal(uint8_t val, uint32_t child)
+{
+        return ((uint8_t) (val & !(COAL_LEFT >> (child % 2))));
+}
+
+static inline uint8_t mark(uint8_t val, uint32_t child)
+{
+        return ((uint8_t) (val | (OCC_LEFT >> (child % 2))));
+}
+
+static inline uint8_t unmark(uint8_t val, uint32_t child)
+{
+        return ((uint8_t) (val & !((COAL_LEFT | OCC_LEFT) >> (child % 2))));
+}
+
+static inline uint8_t is_coal(uint8_t val, uint32_t child)
+{
+        return ((uint8_t) (val & (COAL_LEFT >> (child % 2))));
+}
+
+static inline uint8_t is_occ_buddy(uint8_t val, uint32_t child)
+{
+        return ((uint8_t) (val & (OCC_RIGHT << (child % 2))));
+}
+
+static inline uint8_t is_coal_buddy(uint8_t val, uint32_t child)
+{
+        return ((uint8_t) (val & (COAL_RIGHT << (child % 2))));
+}
+
+static inline uint8_t is_free(uint8_t val)
+{
+        return !(val & BUSY);
+}

Kernel/Main.c

@@ -19,6 +19,7 @@
 #include "Memory/PageDef.h"
 #include "Memory/BootMem.h"
 #include "Memory/Physical.h"
+#include "Memory/NBBS.h"
 #include "Memory/Virtual.h"
 
 /*
@@ -77,17 +78,26 @@ void kmain(boot_sysinfo* boot_params)
                 pageCount, (pageCount * PAGE_SIZE) / 1024
         );
 
-        /* 2. Init PMM */
-        klog("[kmain] Initializing physical memory manager...\n");
+        /* 2. Init NBBS */
+        klog("[kmain] Initializing NBBS...\n");
 
-        uint64_t blockCount = init_allocator(
-                (const void *) boot_params->k_phy_base + boot_params->k_size + pageCount * PAGE_SIZE,
-                (const void *) mem_end
-        );
+        if (nb_init(mem_start, mem_end - mem_start)) {
+                klog("[kmain] Failed to initialize NBBS ;(\n");
+        } else {
+                klog("[kmain] Initialized NBBS!\n");
+        }
 
-        klog("[kmain] 2 MiB blocks available: %lu (%lu MiB) in pmm\n",
-                blockCount, blockCount * 2
-        );
+        /* 2. Init PMM */
+        // klog("[kmain] Initializing physical memory manager...\n");
+        // 
+        // uint64_t blockCount = init_allocator(
+        //         (const void *) boot_params->k_phy_base + boot_params->k_size + pageCount * PAGE_SIZE,
+        //         (const void *) mem_end
+        // );
+
+        // klog("[kmain] 2 MiB blocks available: %lu (%lu MiB) in pmm\n",
+        //         blockCount, blockCount * 2
+        // );
 
         /* 3. Init Kernel Page Tables & Enable MMU */
 

Kernel/Memory/NBBS.c

@@ -0,0 +1,83 @@
+/*
+ * This file (NBSS.c) implements the Non-Blocking Buddy System
+ */
+
+#ifndef NBBS_H
+#define NBBS_H
+
+#include <stdint.h>
+
+#include "LibKern/String.h"
+#include "Libkern/String.h"
+
+#include "Memory/PageDef.h"
+#include "Memory/BootMem.h"
+#include "Memory/NBBS.h"
+
+static volatile uint8_t *tree = 0;
+static volatile uint32_t *index = 0;
+
+static volatile uint64_t tree_size = 0; /* bytes */
+static volatile uint64_t index_size = 0; /* bytes */
+
+/*
+ * Maximum allowed alloc size is: 2^(max_level - 1) * min_size
+ * Naturally max_allowed <= total_memory
+*/
+static volatile uint32_t max_level = 10;
+
+static volatile uint64_t min_size = PAGE_SIZE;
+static volatile uint64_t max_size = 0;
+
+int nb_init(uint64_t base_addr, uint64_t size)
+{
+        if (base_addr == 0 | size == 0) {
+                return 1;
+        }
+
+        /* Calculate required tree size */
+        uint32_t total_nodes = 1; // we start at idx 1
+        for (uint32_t i = 0; i < max_level; i++) {
+                total_nodes += (size / ((0x1 << i) * min_size));
+        }
+
+        /* Calculate required index size */
+        uint32_t total_elems = (size / min_size);
+
+        tree_size = total_nodes * 1;   // each node is 1 byte
+        index_size = total_elems * 4; // each elem is 4 byte
+
+        /* Allocate */
+        uint32_t req_pages = (tree_size + PAGE_SIZE - 1) / PAGE_SIZE;
+        tree = (uint8_t*) bootmem_alloc(req_pages);
+
+        if (!tree) {
+                return 1;
+        } 
+
+        req_pages = (index_size + PAGE_SIZE - 1) / PAGE_SIZE;
+        index = (uint32_t*) bootmem_alloc(req_pages);
+
+        if (!index) {
+                return 1;
+        }
+
+        /* Initialize */
+        memset((void*) tree, 0x0, tree_size);
+        memset((void*) index, 0x0, index_size);
+
+        return 0;
+}
+
+void* nb_alloc(uint64_t size)
+{
+
+}
+
+void* nb_free(void *addr)
+{
+
+}
+
+
+#endif /* NBBS_H */

Makefile

@@ -80,6 +80,7 @@ SRCS = \
 	Kernel/Library/LibKern/Time.c \
 	Kernel/Memory/BootMem.c \
 	Kernel/Memory/Physical.c \
+	Kernel/Memory/NBBS.c \
 	Kernel/Memory/Virtual.c
 OBJS = ${SRCS:.c=.o}
 
@@ -165,7 +166,7 @@ debug:
 
 compiledb:
 	@echo "COMPILEDB -n make all"
-	@python3 -m compiledb -n make all
+	@compiledb -n make all
 	@echo "COMPILEDB -n make all ${GREEN}ok${NC}"
 
 all: