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am 763ac283: Merge changes Ibcba4b4f,I9af341e1 into eclair

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Merge commit '763ac28357f604e0e4196e0a7ad5b0f5cdcf274a' into eclair-mr2

* commit '763ac28357f604e0e4196e0a7ad5b0f5cdcf274a':
  bionic/linker: make the buddy allocator compute max_order on its own
  bionic/linker: change the buddy allocator to take a handle to the managed area
This commit is contained in:
Iliyan Malchev 2009-10-23 18:38:35 -07:00 committed by Android Git Automerger
commit 70bba5160f
3 changed files with 70 additions and 61 deletions
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76
linker/ba.c
View File

@ -30,65 +30,41 @@
#include "linker_debug.h"
#include "ba.h"
struct ba_bits {
unsigned allocated:1; /* 1 if allocated, 0 if free */
unsigned order:7; /* size of the region in ba space */
};
struct ba_info {
/* start address of the ba space */
unsigned long base;
/* total size of the ba space */
unsigned long size;
/* number of entries in the ba space */
int num_entries;
/* the bitmap for the region indicating which entries are allocated
* and which are free */
struct ba_bits *bitmap;
};
#undef min
#define min(a,b) ((a)<(b)?(a):(b))
#define BA_MIN_ALLOC LIBINC
#define BA_MAX_ORDER 128
#define BA_START LIBBASE
#define BA_SIZE (LIBLAST - LIBBASE)
#define BA_IS_FREE(index) (!(ba.bitmap[index].allocated))
#define BA_ORDER(index) ba.bitmap[index].order
#define BA_IS_FREE(index) (!(ba->bitmap[index].allocated))
#define BA_ORDER(index) ba->bitmap[index].order
#define BA_BUDDY_INDEX(index) ((index) ^ (1 << BA_ORDER(index)))
#define BA_NEXT_INDEX(index) ((index) + (1 << BA_ORDER(index)))
#define BA_OFFSET(index) ((index) * BA_MIN_ALLOC)
#define BA_START_ADDR(index) (BA_OFFSET(index) + ba.base)
#define BA_LEN(index) ((1 << BA_ORDER(index)) * BA_MIN_ALLOC)
#define BA_OFFSET(index) ((index) * ba->min_alloc)
#define BA_START_ADDR(index) (BA_OFFSET(index) + ba->base)
#define BA_LEN(index) ((1 << BA_ORDER(index)) * ba->min_alloc)
static struct ba_bits ba_bitmap[BA_SIZE / BA_MIN_ALLOC];
static unsigned long ba_order(struct ba *ba, unsigned long len);
static struct ba_info ba = {
.base = BA_START,
.size = BA_SIZE,
.bitmap = ba_bitmap,
.num_entries = sizeof(ba_bitmap)/sizeof(ba_bitmap[0]),
};
void ba_init(void)
void ba_init(struct ba *ba)
{
int i, index = 0;
for (i = sizeof(ba.num_entries) * 8 - 1; i >= 0; i--) {
if (ba.num_entries & 1<<i) {
unsigned long max_order = ba_order(ba, ba->size);
if (ba->max_order == 0 || ba->max_order > max_order)
ba->max_order = max_order;
for (i = sizeof(ba->num_entries) * 8 - 1; i >= 0; i--) {
if (ba->num_entries & 1<<i) {
BA_ORDER(index) = i;
index = BA_NEXT_INDEX(index);
}
}
}
int ba_free(int index)
int ba_free(struct ba *ba, int index)
{
int buddy, curr = index;
/* clean up the bitmap, merging any buddies */
ba.bitmap[curr].allocated = 0;
ba->bitmap[curr].allocated = 0;
/* find a slots buddy Buddy# = Slot# ^ (1 << order)
* if the buddy is also free merge them
* repeat until the buddy is not free or end of the bitmap is reached
@ -103,16 +79,16 @@ int ba_free(int index)
} else {
break;
}
} while (curr < ba.num_entries);
} while (curr < ba->num_entries);
return 0;
}
static unsigned long ba_order(unsigned long len)
static unsigned long ba_order(struct ba *ba, unsigned long len)
{
unsigned long i;
len = (len + BA_MIN_ALLOC - 1) / BA_MIN_ALLOC;
len = (len + ba->min_alloc - 1) / ba->min_alloc;
len--;
for (i = 0; i < sizeof(len)*8; i++)
if (len >> i == 0)
@ -120,14 +96,14 @@ static unsigned long ba_order(unsigned long len)
return i;
}
int ba_allocate(unsigned long len)
int ba_allocate(struct ba *ba, unsigned long len)
{
int curr = 0;
int end = ba.num_entries;
int end = ba->num_entries;
int best_fit = -1;
unsigned long order = ba_order(len);
unsigned long order = ba_order(ba, len);
if (order > BA_MAX_ORDER)
if (order > ba->max_order)
return -1;
/* look through the bitmap:
@ -165,16 +141,16 @@ int ba_allocate(unsigned long len)
buddy = BA_BUDDY_INDEX(best_fit);
BA_ORDER(buddy) = BA_ORDER(best_fit);
}
ba.bitmap[best_fit].allocated = 1;
ba->bitmap[best_fit].allocated = 1;
return best_fit;
}
unsigned long ba_start_addr(int index)
unsigned long ba_start_addr(struct ba *ba, int index)
{
return BA_START_ADDR(index);
}
unsigned long ba_len(int index)
unsigned long ba_len(struct ba *ba, int index)
{
return BA_LEN(index);
}

31
linker/ba.h
View File

@ -29,10 +29,31 @@
#ifndef __LINKER_BA_H
#define __LINKER_BA_H
extern void ba_init(void);
extern int ba_allocate(unsigned long len);
extern int ba_free(int index);
extern unsigned long ba_start_addr(int index);
extern unsigned long ba_len(int index);
struct ba_bits {
unsigned allocated:1; /* 1 if allocated, 0 if free */
unsigned order:7; /* size of the region in ba space */
};
struct ba {
/* start address of the ba space */
unsigned long base;
/* total size of the ba space */
unsigned long size;
/* the smaller allocation that can be made */
unsigned long min_alloc;
/* the order of the largest allocation that can be made */
unsigned long max_order;
/* number of entries in the ba space */
int num_entries;
/* the bitmap for the region indicating which entries are allocated
* and which are free */
struct ba_bits *bitmap;
};
extern void ba_init(struct ba *ba);
extern int ba_allocate(struct ba *ba, unsigned long len);
extern int ba_free(struct ba *ba, int index);
extern unsigned long ba_start_addr(struct ba *ba, int index);
extern unsigned long ba_len(struct ba *ba, int index);
#endif

24
linker/linker.c
View File

@ -91,6 +91,18 @@ static soinfo *sonext = &libdl_info;
static soinfo *somain; /* main process, always the one after libdl_info */
#endif
/* Set up for the buddy allocator managing the prelinked libraries. */
static struct ba_bits ba_prelink_bitmap[(LIBLAST - LIBBASE) / LIBINC];
static struct ba ba_prelink = {
.base = LIBBASE,
.size = LIBLAST - LIBBASE,
.min_alloc = LIBINC,
/* max_order will be determined automatically */
.bitmap = ba_prelink_bitmap,
.num_entries = sizeof(ba_prelink_bitmap)/sizeof(ba_prelink_bitmap[0]),
};
static inline int validate_soinfo(soinfo *si)
{
return (si >= sopool && si < sopool + SO_MAX) ||
@ -783,14 +795,14 @@ alloc_mem_region(soinfo *si)
for it from the buddy allocator, which manages the area between
LIBBASE and LIBLAST.
*/
si->ba_index = ba_allocate(si->size);
si->ba_index = ba_allocate(&ba_prelink, si->size);
if(si->ba_index >= 0) {
si->base = ba_start_addr(si->ba_index);
si->base = ba_start_addr(&ba_prelink, si->ba_index);
PRINT("%5d mapping library '%s' at %08x (index %d) " \
"through buddy allocator.\n",
pid, si->name, si->base, si->ba_index);
if (reserve_mem_region(si) < 0) {
ba_free(si->ba_index);
ba_free(&ba_prelink, si->ba_index);
si->ba_index = -1;
si->base = 0;
goto err;
@ -1086,7 +1098,7 @@ load_library(const char *name)
/* Now actually load the library's segments into right places in memory */
if (load_segments(fd, &__header[0], si) < 0) {
if (si->ba_index >= 0) {
ba_free(si->ba_index);
ba_free(&ba_prelink, si->ba_index);
si->ba_index = -1;
}
goto fail;
@ -1189,7 +1201,7 @@ unsigned unload_library(soinfo *si)
PRINT("%5d releasing library '%s' address space at %08x "\
"through buddy allocator.\n",
pid, si->name, si->base);
ba_free(si->ba_index);
ba_free(&ba_prelink, si->ba_index);
}
notify_gdb_of_unload(si);
free_info(si);
@ -1897,7 +1909,7 @@ unsigned __linker_init(unsigned **elfdata)
vecs += 2;
}
ba_init();
ba_init(&ba_prelink);
si->base = 0;
si->dynamic = (unsigned *)-1;