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author | Andreas Baumann <mail@andreasbaumann.cc> | 2017-07-05 13:53:42 +0200 |
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committer | Andreas Baumann <mail@andreasbaumann.cc> | 2017-07-05 13:53:42 +0200 |
commit | c55bc80baa51dc1028cbbae8a02540cfe4c56557 (patch) | |
tree | cc8f9e327d9e68eb6aee9ca781838c473074fa60 /src/kernel | |
parent | b281252aac949fe54057608edb20cdfbe20eaed0 (diff) | |
download | abaos-c55bc80baa51dc1028cbbae8a02540cfe4c56557.tar.gz abaos-c55bc80baa51dc1028cbbae8a02540cfe4c56557.tar.bz2 |
'mem' command shows memory usage of kernel heap now
implemented a malloc/free and memory manager (simplest possible implementation,
just allocating linearly and never freeing)
Diffstat (limited to 'src/kernel')
-rw-r--r-- | src/kernel/kernel.c | 34 | ||||
-rw-r--r-- | src/kernel/memorymanagement.c | 40 | ||||
-rw-r--r-- | src/kernel/memorymanagement.h | 16 |
3 files changed, 87 insertions, 3 deletions
diff --git a/src/kernel/kernel.c b/src/kernel/kernel.c index a9802e1..a6594f6 100644 --- a/src/kernel/kernel.c +++ b/src/kernel/kernel.c @@ -42,6 +42,7 @@ typedef struct { vga_text_t vga_text; driver_manager_t driver_manager; task_manager_t task_manager; + memory_manager_t memory_manager; vga_t vga; mode_t mode; mouse_t mouse; @@ -60,6 +61,7 @@ static void refresh_screen( void ); static void switch_to_graphics_mode( global_context_t *global_context ); static void switch_to_text_mode( global_context_t *global_context ); static void print_task_status( global_context_t *global_context ); +static void print_memory_status( global_context_t *global_context ); // must be first entry in kernel.bin (0x8800) as stage 2 of // the boot loader expects the entry point to be here! @@ -78,13 +80,25 @@ void kernel_main( void ) console_init( &console ); console_add_vga_text_output( &console, &global_context.vga_text ); console_add_serial_output( &console, &serial ); - + // initialize the early console of the kernel - stdio_set_console( &console ); + __stdio_set_console( &console ); puts( "Started early kernel console" ); // TODO: get those values somehow from the boot loader printf( "Kernel code and data is at 0x%X, kernel stack at 0x%X\n", 0x8800, 0x90000 ); + // initialize memory management first, we may need it + // TODO: get memupper from multiboot header (but this needs + // a multiboot compliant entry function first) or use BIOS + // functions to determine size of memory, for now assume we + // have at least, for now use the memory above 1 MB, 64 MB + // heap is enough for what we are doing in the kernel + memory_manager_init( &global_context.memory_manager, 0x100000, 0xFFFF ); + __stdlib_set_memory_manager( &global_context.memory_manager ); + printf( "Kernel heap at 0x%X, size 0x%X\n", 0x100000, 0xFFFF ); + void *test = malloc( 2048 ); + free( test ); + // exit point in case of kernel panic, do this as soon as // possible, as soon we have an early console we can croak on if( setjmp( panic_jmp_buf ) > 0 ) { @@ -211,7 +225,7 @@ static void handle_keyboard_event( keyboard_event_t *event, void *context ) } else if( strcmp( buf, "halt" ) == 0 ) { longjmp( panic_jmp_buf, 0 ); } else if( strcmp( buf, "mem" ) == 0 ) { - // TODO: print memory usage + print_memory_status( global_context ); } else if( strcmp( buf, "task" ) == 0 ) { print_task_status( global_context ); } else if( strcmp( buf, "driver" ) == 0 ) { @@ -411,3 +425,17 @@ static void print_task_status( global_context_t *global_context ) } } +static void print_memory_status( global_context_t *global_context ) +{ + memory_manager_t *memory_manager = &global_context->memory_manager; + + printf( "heap memory size: %d\n", memory_manager->size ); + printf( "heap memory offset: 0x%X\n", memory_manager->offset ); + printf( "heap memory in use: %d\n", + memory_manager->free_ptr - memory_manager->offset ); + printf( "heap memory free: %d\n", + memory_manager->size - ( memory_manager->free_ptr - memory_manager->offset ) - 1 ); + +} + + diff --git a/src/kernel/memorymanagement.c b/src/kernel/memorymanagement.c new file mode 100644 index 0000000..dc2d160 --- /dev/null +++ b/src/kernel/memorymanagement.c @@ -0,0 +1,40 @@ +#include "memorymanagement.h" + +#include "string.h" + +#include "kernel.h" + +void memory_manager_init( memory_manager_t *memory_manager, size_t offset, size_t size ) +{ + memset( memory_manager, 0, sizeof( memory_manager_t ) ); + + memory_manager->offset = offset; + memory_manager->size = size; + memory_manager->free_ptr = offset; +} + +void *memory_manager_allocate( memory_manager_t *memory_manager, size_t size ) +{ + void *p = NULL; + + if( memory_manager->free_ptr - memory_manager->offset + size > memory_manager->size ) { + kernel_panic( "Heap allocation out of memory (requested %d bytes, available %d)", + size, size - ( memory_manager->free_ptr - memory_manager->offset ) - 1 ); + } + + p = (void *)memory_manager->free_ptr; + memory_manager->free_ptr += size; + + return p; +} + +void memory_manager_deallocate( memory_manager_t *memory_manager, void **p ) +{ + if( *p == NULL ) { + kernel_panic( "Double free of pointer 0x%X in heap", *p ); + } + + *p = NULL; +} + + diff --git a/src/kernel/memorymanagement.h b/src/kernel/memorymanagement.h new file mode 100644 index 0000000..16f0b29 --- /dev/null +++ b/src/kernel/memorymanagement.h @@ -0,0 +1,16 @@ +#ifndef MEMORYMANAGEMENT_H +#define MEMORYMANAGEMENT_H + +#include "stddef.h" + +typedef struct { + size_t offset; + size_t size; + uint32_t free_ptr; +} memory_manager_t; + +void memory_manager_init( memory_manager_t *memory_manager, size_t offset, size_t size ); +void *memory_manager_allocate( memory_manager_t *memory_manager, size_t size ); +void memory_manager_deallocate( memory_manager_t *memory_manager, void **p ); + +#endif // MEMORYMANAGEMENT_H |