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Code Issues Releases Activity

Use auto LDT allocation for i386.

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This commit is contained in:
Daniel Eischen 2003-08-05 23:09:22 +00:00
parent b8b90678e3
commit 199d58cbfc
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=118512
2 changed files with 12 additions and 126 deletions
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69
lib/libkse/arch/i386/i386/pthread_md.c
View File

@ -41,58 +41,6 @@ __FBSDID("$FreeBSD$");
#include "pthread_md.h"
#define LDT_ENTRIES 8192
#define LDT_WORDS (8192/sizeof(unsigned int))
#define LDT_RESERVED NLDT
static unsigned int ldt_mask[LDT_WORDS];
static int initialized = 0;
static void initialize(void);
static void
initialize(void)
{
int i, j;
memset(ldt_mask, 0xFF, sizeof(ldt_mask));
/* Reserve system predefined LDT entries */
for (i = 0; i < LDT_RESERVED; ++i) {
j = i / 32;
ldt_mask[j] &= ~(1 << (i % 32));
}
initialized = 1;
}
static u_int
alloc_ldt_entry(void)
{
u_int i, j, index;
index = 0;
for (i = 0; i < LDT_WORDS; ++i) {
if (ldt_mask[i] != 0) {
j = bsfl(ldt_mask[i]);
ldt_mask[i] &= ~(1 << j);
index = i * 32 + j;
break;
}
}
return (index);
}
static void
free_ldt_entry(u_int index)
{
u_int i, j;
if (index < LDT_RESERVED || index >= LDT_ENTRIES)
return;
i = index / 32;
j = index % 32;
ldt_mask[i] |= (1 << j);
}
struct tcb *
_tcb_ctor(struct pthread *thread)
{
@ -131,18 +79,11 @@ _kcb_ctor(struct kse *kse)
union descriptor ldt;
struct kcb *kcb;
if (initialized == 0)
initialize();
kcb = malloc(sizeof(struct kcb));
if (kcb != NULL) {
bzero(kcb, sizeof(struct kcb));
kcb->kcb_self = kcb;
kcb->kcb_kse = kse;
kcb->kcb_ldt = alloc_ldt_entry();
if (kcb->kcb_ldt == 0) {
free(kcb);
return (NULL);
}
ldt.sd.sd_hibase = (unsigned int)kcb >> 24;
ldt.sd.sd_lobase = (unsigned int)kcb & 0xFFFFFF;
ldt.sd.sd_hilimit = (sizeof(struct kcb) >> 16) & 0xF;
@ -153,8 +94,8 @@ _kcb_ctor(struct kse *kse)
ldt.sd.sd_xx = 0;
ldt.sd.sd_def32 = 1;
ldt.sd.sd_gran = 0; /* no more than 1M */
if (i386_set_ldt(kcb->kcb_ldt, &ldt, 1) < 0) {
free_ldt_entry(kcb->kcb_ldt);
kcb->kcb_ldt = i386_set_ldt(LDT_AUTO_ALLOC, &ldt, 1);
if (kcb->kcb_ldt < 0) {
free(kcb);
return (NULL);
}
@ -165,7 +106,9 @@ _kcb_ctor(struct kse *kse)
void
_kcb_dtor(struct kcb *kcb)
{
if (kcb->kcb_ldt != -1)
free_ldt_entry(kcb->kcb_ldt);
if (kcb->kcb_ldt >= 0) {
i386_set_ldt(kcb->kcb_ldt, NULL, 1);
kcb->kcb_ldt = -1; /* just in case */
}
free(kcb);
}

69
lib/libpthread/arch/i386/i386/pthread_md.c
View File

@ -41,58 +41,6 @@ __FBSDID("$FreeBSD$");
#include "pthread_md.h"
#define LDT_ENTRIES 8192
#define LDT_WORDS (8192/sizeof(unsigned int))
#define LDT_RESERVED NLDT
static unsigned int ldt_mask[LDT_WORDS];
static int initialized = 0;
static void initialize(void);
static void
initialize(void)
{
int i, j;
memset(ldt_mask, 0xFF, sizeof(ldt_mask));
/* Reserve system predefined LDT entries */
for (i = 0; i < LDT_RESERVED; ++i) {
j = i / 32;
ldt_mask[j] &= ~(1 << (i % 32));
}
initialized = 1;
}
static u_int
alloc_ldt_entry(void)
{
u_int i, j, index;
index = 0;
for (i = 0; i < LDT_WORDS; ++i) {
if (ldt_mask[i] != 0) {
j = bsfl(ldt_mask[i]);
ldt_mask[i] &= ~(1 << j);
index = i * 32 + j;
break;
}
}
return (index);
}
static void
free_ldt_entry(u_int index)
{
u_int i, j;
if (index < LDT_RESERVED || index >= LDT_ENTRIES)
return;
i = index / 32;
j = index % 32;
ldt_mask[i] |= (1 << j);
}
struct tcb *
_tcb_ctor(struct pthread *thread)
{
@ -131,18 +79,11 @@ _kcb_ctor(struct kse *kse)
union descriptor ldt;
struct kcb *kcb;
if (initialized == 0)
initialize();
kcb = malloc(sizeof(struct kcb));
if (kcb != NULL) {
bzero(kcb, sizeof(struct kcb));
kcb->kcb_self = kcb;
kcb->kcb_kse = kse;
kcb->kcb_ldt = alloc_ldt_entry();
if (kcb->kcb_ldt == 0) {
free(kcb);
return (NULL);
}
ldt.sd.sd_hibase = (unsigned int)kcb >> 24;
ldt.sd.sd_lobase = (unsigned int)kcb & 0xFFFFFF;
ldt.sd.sd_hilimit = (sizeof(struct kcb) >> 16) & 0xF;
@ -153,8 +94,8 @@ _kcb_ctor(struct kse *kse)
ldt.sd.sd_xx = 0;
ldt.sd.sd_def32 = 1;
ldt.sd.sd_gran = 0; /* no more than 1M */
if (i386_set_ldt(kcb->kcb_ldt, &ldt, 1) < 0) {
free_ldt_entry(kcb->kcb_ldt);
kcb->kcb_ldt = i386_set_ldt(LDT_AUTO_ALLOC, &ldt, 1);
if (kcb->kcb_ldt < 0) {
free(kcb);
return (NULL);
}
@ -165,7 +106,9 @@ _kcb_ctor(struct kse *kse)
void
_kcb_dtor(struct kcb *kcb)
{
if (kcb->kcb_ldt != -1)
free_ldt_entry(kcb->kcb_ldt);
if (kcb->kcb_ldt >= 0) {
i386_set_ldt(kcb->kcb_ldt, NULL, 1);
kcb->kcb_ldt = -1; /* just in case */
}
free(kcb);
}