Perform proper memory commit. Many bug fizes

src/platform.c

@@ -1,29 +1,16 @@
 #include "base_core.h"
+#include "platform.h"
 #include <stdlib.h>
 #include <stdio.h>
 #include <unistd.h>
 #include <sys/mman.h>
 
 
+#define IsPageAligned(x) (IsAlignedToPow2(x, platform_page_size()))
+
 U32 platform_page_size(void)
 {
-    return getpagesize();
-}
-
-static INLINE size_t AlignToPageSize(size_t size)
-{
-    U32 page_size = platform_page_size();
-    size_t aligned_size = AlignUpPow2(size, page_size);
-
-    return aligned_size;
-}
-
-static INLINE size_t AlignToPageStart(size_t size)
-{
-    U32 page_size = platform_page_size();
-    size_t aligned_size = AlignDownPow2(size, page_size);
-
-    return aligned_size;
+    return sysconf(_SC_PAGESIZE);
 }
 
 void *platform_malloc(size_t size)
@@ -36,54 +23,67 @@ void platform_free(void *mem)
     free(mem);
 }
 
-
-void *memory_allocate(size_t size)
+void *memory_allocate_and_commit(size_t size)
 {
-    if (size == 0) {
-        size = 1;
+    Assert(IsPageAligned(size));
+
+    void *mem = mmap(0, size, PROT_READ | PROT_WRITE, MAP_ANONYMOUS  | MAP_PRIVATE, -1, 0);
+    TRACEF("memory_allocate size=%7zu mem=%p\n", size, mem);
+    if (mem == MAP_FAILED) {
+        mem = NULL;
+    } else {
+        int rc = madvise(mem, size, MADV_POPULATE_WRITE);
+        if (rc != 0) {
+            munmap(mem, size);
+            mem = NULL;
+        }
     }
 
-    size_t aligned_size = AlignToPageSize(size);
-    void *mem = mmap(0, aligned_size, PROT_READ | PROT_WRITE, MAP_ANONYMOUS  | MAP_PRIVATE, -1, 0);
-    TRACEF("memory_allocate size=%zu aligned_size=%zu mem=%p\n", size, aligned_size, mem);
+    return mem;
+}
+
+void memory_free(void *mem, size_t size)
+{
+    TRACEF("        memory_free     size=%7zu mem=%p\n", size, mem);
+    Assert(IsPageAligned((uintptr_t)mem));
+    Assert(IsPageAligned(size));
+    int rc = munmap(mem, size);
+
+    Assert(rc == 0);
+
+}
+void *memory_reserve(size_t size)
+{
+    Assert(IsPageAligned(size));
+    void *mem = mmap(0, size, PROT_NONE, MAP_ANONYMOUS  | MAP_PRIVATE, -1, 0);
+    TRACEF("memory_reserve  size=%7zu mem=%p\n", size, mem);
     if (mem == MAP_FAILED) {
         mem = NULL;
     }
     return mem;
 }
 
-void memory_free(void *mem, size_t size)
-{
-    size_t aligned_size = AlignToPageSize(size);
-    TRACEF("        memory_free     size=%zu aligned_size=%zu mem=%p\n", size, aligned_size, mem);
-
-    int rc = munmap(mem, aligned_size);
-
-    Assert(rc == 0);
-}
-
 void memory_commit(void *mem, size_t size)
 {
-    size_t aligned_size = AlignToPageSize(size);
-    void *aligned_mem = (void *)AlignToPageStart((uintptr_t)mem);
-    TRACEF("memory_commit size=%zu aligned_size=%zu ptr=%p aligned_mem=%p\n", size, aligned_size, mem, aligned_mem);
+    Assert(IsPageAligned((uintptr_t)mem));
+    Assert(IsPageAligned(size));
+    TRACEF("memory_commit   size=%7zu mem=%p\n", size, mem);
 
     int rc;
-    rc = mprotect(aligned_mem, aligned_size, PROT_READ | PROT_WRITE);
+    rc = mprotect(mem, size, PROT_READ | PROT_WRITE);
     Assert(rc == 0);
-    rc = madvise(aligned_mem, aligned_size, MADV_WILLNEED);
+    rc = madvise(mem, size, MADV_WILLNEED);
     Assert(rc == 0);
 }
 
 void memory_decommit(void *mem, size_t size)
 {
-    size_t aligned_size = AlignToPageSize(size);
-    void *aligned_mem = (void *)AlignToPageStart((uintptr_t)mem);
-    TRACEF("memory_commit size=%zu aligned_size=%zu ptr=%p aligned_mem=%p\n", size, aligned_size, mem, aligned_mem);
-
+    TRACEF("memory_decommit size=%7zu mem=%p\n", size, mem);
+    Assert(IsPageAligned((uintptr_t)mem));
+    Assert(IsPageAligned(size));
     int rc;
-    rc = mprotect(aligned_mem, aligned_size, PROT_NONE);
+    rc = mprotect(mem, size, PROT_NONE);
     Assert(rc == 0);
-    rc = madvise(aligned_mem, aligned_size, MADV_DONTNEED);
+    rc = madvise(mem, size, MADV_DONTNEED);
     Assert(rc == 0);
 }