0.8.20.20:

[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 07b8e33..15eb762 100644 (file)
--- a/src/runtime/x86-linux-os.c
+++ b/src/runtime/x86-linux-os.c
@@ -22,6 +22,7 @@
 #include <unistd.h>
 #include <errno.h>
 
+#include "sbcl.h"
 #include "./signal.h"
 #include "os.h"
 #include "arch.h"
@@ -29,7 +30,6 @@
 #include "interrupt.h"
 #include "interr.h"
 #include "lispregs.h"
-#include "sbcl.h"
 #include <sys/socket.h>
 #include <sys/utsname.h>
 
@@ -42,8 +42,13 @@
 #include <asm/ldt.h>
 #include <linux/unistd.h>
 #include <sys/mman.h>
+#include <linux/version.h>
 #include "thread.h"            /* dynamic_values_bytes */
 
+#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,0)
+#define user_desc  modify_ldt_ldt_s 
+#endif
+
 _syscall3(int, modify_ldt, int, func, void *, ptr, unsigned long, bytecount );
 
 #include "validate.h"
@@ -51,9 +56,8 @@ size_t os_vm_page_size;
 
 u32 local_ldt_copy[LDT_ENTRIES*LDT_ENTRY_SIZE/sizeof(u32)];
 
-/* XXX this could be conditionally compiled based on some
- * "debug-friendly" flag.  But it doesn't really make stuff slower,
- * just the runtime gets fractionally larger */
+/* This is never actually called, but it's great for calling from gdb when
+ * users have thread-related problems that maintainers can't duplicate */
 
 void debug_get_ldt()
 { 
@@ -61,15 +65,15 @@ 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 */
+volatile 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
-    /* this must be called from a function that has an exclusive lock
-     * on all_threads
+    /* FIXME Lock ordering rules: all_threads_lock must usually be
+     * held when getting modify_ldt_lock
      */
-    struct modify_ldt_ldt_s ldt_entry = {
+    struct user_desc ldt_entry = {
        1, 0, 0, /* index, address, length filled in later */
        1, MODIFY_LDT_CONTENTS_DATA, 0, 0, 0, 1
     }; 
@@ -113,21 +117,6 @@ int arch_os_thread_init(struct thread *thread) {
     return 1;
 }
 
-/* if you can't do something like this (maybe because you're using a 
- * register for thread base that is only available in Lisp code)
- * you'll just have to find_thread_by_pid(getpid())
- */
-struct thread *arch_os_get_current_thread() {
-#ifdef LISP_FEATURE_SB_THREAD
-    register struct thread *me=0;
-    if(all_threads)
-       __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)  : );
@@ -139,7 +128,7 @@ struct thread *debug_get_fs() {
  */
 
 int arch_os_thread_cleanup(struct thread *thread) {
-    struct modify_ldt_ldt_s ldt_entry = {
+    struct user_desc ldt_entry = {
        0, 0, 0, 
        0, MODIFY_LDT_CONTENTS_DATA, 0, 0, 0, 0
     };