[PATCH] alpha: Fix getxpid on alpha so it works for threads
While looking in the code I discovered that alpha has fallen behind because
it doesn't use sys_getppid. The problem is that it doesn't follow the task
struct to the task_group_leader.
Acked-by: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/arch/alpha/kernel/asm-offsets.c b/arch/alpha/kernel/asm-offsets.c
index 8f2e5c7..6c56c75 100644
--- a/arch/alpha/kernel/asm-offsets.c
+++ b/arch/alpha/kernel/asm-offsets.c
@@ -28,6 +28,7 @@
DEFINE(TASK_GID, offsetof(struct task_struct, gid));
DEFINE(TASK_EGID, offsetof(struct task_struct, egid));
DEFINE(TASK_REAL_PARENT, offsetof(struct task_struct, real_parent));
+ DEFINE(TASK_GROUP_LEADER, offsetof(struct task_struct, group_leader));
DEFINE(TASK_TGID, offsetof(struct task_struct, tgid));
BLANK();
diff --git a/arch/alpha/kernel/entry.S b/arch/alpha/kernel/entry.S
index e38671c..7af15bf 100644
--- a/arch/alpha/kernel/entry.S
+++ b/arch/alpha/kernel/entry.S
@@ -879,17 +879,19 @@
/* See linux/kernel/timer.c sys_getppid for discussion
about this loop. */
- ldq $3, TASK_REAL_PARENT($2)
-1: ldl $1, TASK_TGID($3)
+ ldq $3, TASK_GROUP_LEADER($2)
+ ldq $4, TASK_REAL_PARENT($3)
+ ldl $0, TASK_TGID($2)
+1: ldl $1, TASK_TGID($4)
#ifdef CONFIG_SMP
- mov $3, $4
+ mov $4, $5
mb
- ldq $3, TASK_REAL_PARENT($2)
- cmpeq $3, $4, $4
- beq $4, 1b
+ ldq $3, TASK_GROUP_LEADER($2)
+ ldq $4, TASK_REAL_PARENT($3)
+ cmpeq $4, $5, $5
+ beq $5, 1b
#endif
stq $1, 80($sp)
- ldl $0, TASK_TGID($2)
ret
.end sys_getxpid
