christoph/lecture-operating-system-development
1
Fork 0
Code Activity

add vorgabe03 + initial bump allocator

Browse Source
This commit is contained in:
churl
2022-05-06 11:28:20 +02:00
parent ab7a9c2ecb
commit 4ee0b701d7
17 changed files with 472 additions and 59 deletions
Download Patch File Download Diff File Expand all files Collapse all files

80
c_os/kernel/allocator/BumpAllocator.cc Normal file
View File

@ -0,0 +1,80 @@
/*****************************************************************************
* *
* B U M P A L L O C A T O R *
* *
*---------------------------------------------------------------------------*
* Beschreibung: Eine sehr einfache Heap-Verwaltung, welche freigegebenen *
* Speicher nicht mehr nutzen kann. *
* *
* Autor: Michael Schoettner, HHU, 3.3.2022 *
*****************************************************************************/
#include "kernel/Globals.h"
#include <stddef.h>
// #include "kernel/allocator/LinkedListAllocator.h"
/*****************************************************************************
* Methode: BumpAllocator::init *
*---------------------------------------------------------------------------*
* Beschreibung: BumpAllokartor intitialisieren. *
*****************************************************************************/
void BumpAllocator::init() {
/* Hier muess Code eingefuegt werden */
this->heap_start = 3 * 1024 * 1024; // 3 MB
this->heap_size = 1 * 1024 * 1024; // 1 MB
this->heap_end = this->heap_start + this->heap_size; // 4 MB
this->allocations = 0;
this->next = (unsigned char*)heap_start;
this->initialized = true;
}
/*****************************************************************************
* Methode: BumpAllocator::dump_free_memory *
*---------------------------------------------------------------------------*
* Beschreibung: Ausgabe der Freispeicherinfos. Zu Debuggingzwecken. *
*****************************************************************************/
void BumpAllocator::dump_free_memory() {
/* Hier muess Code eingefuegt werden */
kout << "Freier Speicher:" << endl
<< " Heap Start: " << this->heap_start << ", Heap End: " << this->heap_end << endl
<< " Next: " << this->next << ", Allocations: " << this->allocations << endl;
}
/*****************************************************************************
* Methode: BumpAllocator::alloc *
*---------------------------------------------------------------------------*
* Beschreibung: Einen neuen Speicherblock allozieren. *
*****************************************************************************/
void* BumpAllocator::alloc(unsigned int req_size) {
/* Hier muess Code eingefuegt werden */
if (!this->initialized) {
kout << "Allocator not initialized :(" << endl;
return NULL;
}
if (req_size > this->heap_end - (unsigned int)this->next) {
kout << "More memory requested than available :(" << endl;
return NULL;
}
void* allocated = this->next;
this->next = this->next + req_size;
this->allocations = this->allocations + 1;
return allocated;
}
/*****************************************************************************
* Methode: BumpAllocator::free *
*---------------------------------------------------------------------------*
* Beschreibung: Nicht implementiert. *
*****************************************************************************/
void BumpAllocator::free(void* ptr) {
kout << " mm_free: ptr= " << hex << (unsigned int)ptr << ", not supported" << endl;
}