On 17 Nov 2002, Luca Barbieri wrote:
> > the attached patch
> -> The patch that was meant to be attached :)
yeah ...
--- linux/arch/i386/kernel/entry.S.orig 2002-11-17 11:22:18.000000000 +0100
+++ linux/arch/i386/kernel/entry.S 2002-11-17 11:31:32.000000000 +0100
@@ -193,10 +193,8 @@
ENTRY(ret_from_fork)
-#if CONFIG_SMP || CONFIG_PREEMPT
# NOTE: this function takes a parameter but it's unused on x86.
call schedule_tail
-#endif
GET_THREAD_INFO(%ebx)
jmp syscall_exit
@@ -767,6 +765,7 @@
.long sys_epoll_ctl /* 255 */
.long sys_epoll_wait
.long sys_remap_file_pages
+ .long sys_set_tid_address
.rept NR_syscalls-(.-sys_call_table)/4
--- linux/include/linux/sched.h.orig 2002-11-17 11:26:53.000000000 +0100
+++ linux/include/linux/sched.h 2002-11-17 12:58:20.000000000 +0100
@@ -46,10 +46,9 @@
#define CLONE_NEWNS 0x00020000 /* New namespace group? */
#define CLONE_SYSVSEM 0x00040000 /* share system V SEM_UNDO semantics */
#define CLONE_SETTLS 0x00080000 /* create a new TLS for the child */
-#define CLONE_SETTID 0x00100000 /* write the TID back to userspace */
-#define CLONE_CLEARTID 0x00200000 /* clear the userspace TID */
-#define CLONE_DETACHED 0x00400000 /* parent wants no child-exit signal */
-#define CLONE_UNTRACED 0x00800000 /* set if the tracing process can't force CLONE_PTRACE on this clone */
+#define CLONE_SETTID 0x00100000 /* set/clear the TID */
+#define CLONE_DETACHED 0x00200000 /* parent wants no child-exit signal */
+#define CLONE_UNTRACED 0x00400000 /* set if the tracing process can't force CLONE_PTRACE on this clone */
/*
* List of flags we want to share for kernel threads,
@@ -332,7 +331,7 @@
wait_queue_head_t wait_chldexit; /* for wait4() */
struct completion *vfork_done; /* for vfork() */
- int *user_tid; /* for CLONE_CLEARTID */
+ int *user_tid; /* for CLONE_SETTID */
unsigned long rt_priority;
unsigned long it_real_value, it_prof_value, it_virt_value;
--- linux/kernel/sched.c.orig 2002-11-17 11:22:48.000000000 +0100
+++ linux/kernel/sched.c 2002-11-17 11:30:58.000000000 +0100
@@ -503,12 +503,16 @@
* schedule_tail - first thing a freshly forked thread must call.
* @prev: the thread we just switched away from.
*/
-#if CONFIG_SMP || CONFIG_PREEMPT
+asmlinkage void FASTCALL(schedule_tail(task_t *prev));
asmlinkage void schedule_tail(task_t *prev)
{
finish_arch_switch(this_rq(), prev);
+ /*
+ * Does the child thread/process want to be notified of the TID/PID?
+ */
+ if (current->user_tid)
+ put_user(current->pid, current->user_tid);
}
-#endif
/*
* context_switch - switch to the new MM and the new
--- linux/kernel/fork.c.orig 2002-11-17 11:25:35.000000000 +0100
+++ linux/kernel/fork.c 2002-11-17 12:40:44.000000000 +0100
@@ -676,6 +676,13 @@
p->flags = new_flags;
}
+asmlinkage int sys_set_tid_address(int *user_tid)
+{
+ current->user_tid = user_tid;
+
+ return current->pid;
+}
+
/*
* This creates a new process as a copy of the old one,
* but does not actually start it yet.
@@ -813,18 +820,14 @@
if (retval)
goto bad_fork_cleanup_namespace;
/*
- * Notify the child of the TID?
+ * Does the userspace VM want the TID set in the child's
+ * address space and it cleared on mm_release()?
*/
- retval = -EFAULT;
- if (clone_flags & CLONE_SETTID)
- if (put_user(p->pid, user_tid))
- goto bad_fork_cleanup_namespace;
-
- /*
- * Does the userspace VM want the TID cleared on mm_release()?
- */
- if (clone_flags & CLONE_CLEARTID)
+ if (clone_flags & CLONE_SETTID) {
p->user_tid = user_tid;
+ if (clone_flags & CLONE_VM)
+ put_user(p->pid, user_tid);
+ }
/*
* Syscall tracing should be turned off in the child regardless
-
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This archive was generated by hypermail 2b29 : Sat Nov 23 2002 - 22:00:19 EST