-ENTRY(fsys_getppid)
- .prologue
- .altrp b6
- .body
- add r17=IA64_TASK_GROUP_LEADER_OFFSET,r16
- ;;
- ld8 r17=[r17] // r17 = current->group_leader
- add r9=TI_FLAGS+IA64_TASK_SIZE,r16
- ;;
-
- ld4 r9=[r9]
- add r17=IA64_TASK_REAL_PARENT_OFFSET,r17 // r17 = ¤t->group_leader->real_parent
- ;;
- and r9=TIF_ALLWORK_MASK,r9
-
-1: ld8 r18=[r17] // r18 = current->group_leader->real_parent
- ;;
- cmp.ne p8,p0=0,r9
- add r8=IA64_TASK_TGID_OFFSET,r18 // r8 = ¤t->group_leader->real_parent->tgid
- ;;
-
- /*
- * The .acq is needed to ensure that the read of tgid has returned its data before
- * we re-check "real_parent".
- */
- ld4.acq r8=[r8] // r8 = current->group_leader->real_parent->tgid
-#ifdef CONFIG_SMP
- /*
- * Re-read current->group_leader->real_parent.
- */
- ld8 r19=[r17] // r19 = current->group_leader->real_parent
-(p8) br.spnt.many fsys_fallback_syscall
- ;;
- cmp.ne p6,p0=r18,r19 // did real_parent change?
- mov r19=0 // i must not leak kernel bits...
-(p6) br.cond.spnt.few 1b // yes -> redo the read of tgid and the check
- ;;
- mov r17=0 // i must not leak kernel bits...
- mov r18=0 // i must not leak kernel bits...
-#else
- mov r17=0 // i must not leak kernel bits...
- mov r18=0 // i must not leak kernel bits...
- mov r19=0 // i must not leak kernel bits...
-#endif
- FSYS_RETURN
-END(fsys_getppid)
-