0.8.1.50

[sbcl.git] / src / runtime / x86-linux-os.c

diff --git a/src/runtime/x86-linux-os.c b/src/runtime/x86-linux-os.c
index 140f0fd..f02ea8d 100644 (file)
--- a/src/runtime/x86-linux-os.c
+++ b/src/runtime/x86-linux-os.c
@@ -20,6 +20,7 @@
 #include <sys/file.h>
 #include <sys/types.h>
 #include <unistd.h>
+#include <errno.h>
 
 #include "./signal.h"
 #include "os.h"
@@ -60,6 +61,8 @@ void debug_get_ldt()
     printf("%d bytes in ldt: print/x local_ldt_copy\n", n);
 }
 
+lispobj modify_ldt_lock;       /* protect all calls to modify_ldt */
+
 int arch_os_thread_init(struct thread *thread) {
     stack_t sigstack;
 #ifdef LISP_FEATURE_SB_THREAD
@@ -70,8 +73,11 @@ int arch_os_thread_init(struct thread *thread) {
        1, 0, 0, /* index, address, length filled in later */
        1, MODIFY_LDT_CONTENTS_DATA, 0, 0, 0, 1
     }; 
+    int n;
+    get_spinlock(&modify_ldt_lock,thread);
+    n=modify_ldt(0,local_ldt_copy,sizeof local_ldt_copy);
     /* get next free ldt entry */
-    int n=modify_ldt(0,local_ldt_copy,sizeof local_ldt_copy);
+
     if(n) {
        u32 *p;
        for(n=0,p=local_ldt_copy;*p;p+=LDT_ENTRY_SIZE/sizeof(u32))
@@ -81,14 +87,18 @@ int arch_os_thread_init(struct thread *thread) {
     ldt_entry.base_addr=(unsigned long) thread;
     ldt_entry.limit=dynamic_values_bytes;
     ldt_entry.limit_in_pages=0;
-    if (modify_ldt (1, &ldt_entry, sizeof (ldt_entry)) != 0) 
+    if (modify_ldt (1, &ldt_entry, sizeof (ldt_entry)) != 0) {
+       modify_ldt_lock=0;
        /* modify_ldt call failed: something magical is not happening */
        return -1;
+    }
     __asm__ __volatile__ ("movw %w0, %%fs" : : "q" 
                          ((n << 3) /* selector number */
                           + (1 << 2) /* TI set = LDT */
                           + 3)); /* privilege level */
     thread->tls_cookie=n;
+    modify_ldt_lock=0;
+
     if(n<0) return 0;
 #endif
 #ifdef LISP_FEATURE_C_STACK_IS_CONTROL_STACK
@@ -111,13 +121,18 @@ struct thread *arch_os_get_current_thread() {
 #ifdef LISP_FEATURE_SB_THREAD
     register struct thread *me=0;
     if(all_threads)
-       __asm__ ("movl %%fs:%c1,%0" : "=r" (me)
+       __asm__ __volatile__ ("movl %%fs:%c1,%0" : "=r" (me)
                 : "i" (offsetof (struct thread,this)));
     return me;
 #else
     return all_threads;
 #endif
 }
+struct thread *debug_get_fs() {
+    register u32 fs;
+    __asm__ __volatile__ ("movl %%fs,%0" : "=r" (fs)  : );
+    return fs;
+}
 
 /* free any arch/os-specific resources used by thread, which is now
  * defunct.  Not called on live threads
@@ -130,9 +145,13 @@ int arch_os_thread_cleanup(struct thread *thread) {
     }; 
 
     ldt_entry.entry_number=thread->tls_cookie;
-    if (modify_ldt (1, &ldt_entry, sizeof (ldt_entry)) != 0) 
+    get_spinlock(&modify_ldt_lock,thread);
+    if (modify_ldt (1, &ldt_entry, sizeof (ldt_entry)) != 0) {
+       modify_ldt_lock=0;
        /* modify_ldt call failed: something magical is not happening */
        return 0;
+    }
+    modify_ldt_lock=0;
     return 1;
 }