bitkeeper revision 1.862 (407bfad05PmdmZtBnhfJMLp1dqPBYQ)

Various cleanups. Also fix a bug in Xenolinux timer interrupt.

5 files changed, 21 insertions, 20 deletions

diff --git a/xen/common/schedule.c b/xen/common/schedule.c
index 2655b08c28..dfacb65bd0 100644
--- a/xen/common/schedule.c
+++ b/xen/common/schedule.c
@@ -558,8 +558,6 @@ static void t_timer_fn(unsigned long unused)
 
     TRACE_0D(TRC_SCHED_T_TIMER_FN);
 
-    TRACE_0D(TRC_SCHED_T_TIMER_FN);
-
     if ( !is_idle_task(p) )
         send_guest_virq(p, VIRQ_TIMER);
 
diff --git a/xen/include/xen/event.h b/xen/include/xen/event.h
index 542cd3c6ef..320a265a4c 100644
--- a/xen/include/xen/event.h
+++ b/xen/include/xen/event.h
@@ -56,7 +56,7 @@ static inline void evtchn_set_pending(struct task_struct *p, int port)
          !test_and_set_bit(port>>5, &s->evtchn_pending_sel) )
     {
         /* The VCPU pending flag must be set /after/ update to evtchn-pend. */
-        p->shared_info->vcpu_data[0].evtchn_upcall_pending = 1;
+        s->vcpu_data[0].evtchn_upcall_pending = 1;
         guest_schedule_to_run(p);
     }
 }
diff --git a/xenolinux-2.4.25-sparse/arch/xen/kernel/entry.S b/xenolinux-2.4.25-sparse/arch/xen/kernel/entry.S
index b78c74fd9c..305bd42c70 100644
--- a/xenolinux-2.4.25-sparse/arch/xen/kernel/entry.S
+++ b/xenolinux-2.4.25-sparse/arch/xen/kernel/entry.S
@@ -15,7 +15,7 @@
  * I changed all the .align's to 4 (16 byte alignment), as that's faster
  * on a 486.
  *
- * Stack layout in 'ret_from_system_call':
+ * Stack layout in 'ret_to_user':
  * 	ptrace needs to have all regs on the stack.
  *	if the order here is changed, it needs to be
  *	updated in fork.c:copy_process, signal.c:do_signal,
@@ -157,7 +157,7 @@ ENTRY(lcall7)
 	call *%edx
 	addl $4, %esp
 	popl %eax
-	jmp ret_from_sys_call
+	jmp ret_to_user
 
 ENTRY(lcall27)
 	pushfl			# We get a different stack layout with call
@@ -181,7 +181,7 @@ ENTRY(lcall27)
 	call *%edx
 	addl $4, %esp
 	popl %eax
-	jmp ret_from_sys_call
+	jmp ret_to_user
 
 ENTRY(ret_from_fork)
 	pushl %ebx
@@ -190,7 +190,7 @@ ENTRY(ret_from_fork)
 	GET_CURRENT(%ebx)
 	testb $0x02,tsk_ptrace(%ebx)	# PT_TRACESYS
 	jne tracesys_exit
-	jmp	ret_from_sys_call
+	jmp ret_to_user
 
 /*
  * Return to user mode is not as complex as all this looks,
@@ -208,15 +208,15 @@ ENTRY(system_call)
 	jae badsys
 	call *SYMBOL_NAME(sys_call_table)(,%eax,4)
 	movl %eax,EAX(%esp)		# save the return value
-ENTRY(ret_from_sys_call)
+ret_to_user:
         movl SYMBOL_NAME(HYPERVISOR_shared_info),%esi
         movb $1,evtchn_upcall_mask(%esi) # make tests atomic
-ret_syscall_tests:
+ret_to_user_nocli:
 	cmpl $0,need_resched(%ebx)
-	jne reschedule
+	jne  reschedule
 	cmpl $0,sigpending(%ebx)
 	je   safesti                    # ensure need_resched updates are seen
-signal_return:
+/*signal_return:*/
 	movb $0,evtchn_upcall_mask(%esi) # reenable event callbacks
 	movl %esp,%eax
 	xorl %edx,%edx
@@ -238,10 +238,10 @@ tracesys:
 	movl %eax,EAX(%esp)		# save the return value
 tracesys_exit:
 	call SYMBOL_NAME(syscall_trace)
-	jmp ret_from_sys_call
+	jmp ret_to_user
 badsys:
 	movl $-ENOSYS,EAX(%esp)
-	jmp ret_from_sys_call
+	jmp ret_to_user
 
 	ALIGN
 ENTRY(ret_from_intr)
@@ -249,14 +249,14 @@ ENTRY(ret_from_intr)
 ret_from_exception:
 	movb CS(%esp),%al
 	testl $2,%eax
-	jne ret_from_sys_call
+	jne ret_to_user
 	jmp restore_all
 
 	ALIGN
 reschedule:
         movb $0,evtchn_upcall_mask(%esi)  # reenable event callbacks
 	call SYMBOL_NAME(schedule)        # test
-	jmp  ret_from_sys_call
+	jmp  ret_to_user
 
 ENTRY(divide_error)
 	pushl $0		# no error code
@@ -316,7 +316,7 @@ ENTRY(hypervisor_callback)
         movl SYMBOL_NAME(HYPERVISOR_shared_info),%esi
         movb CS(%esp),%cl
 	test $2,%cl          # slow return to ring 2 or 3
-	jne  ret_syscall_tests
+	jne  ret_to_user_nocli
 safesti:movb $0,evtchn_upcall_mask(%esi) # reenable event callbacks
 scrit:  /**** START OF CRITICAL REGION ****/
         testb $0xFF,evtchn_upcall_pending(%esi)
diff --git a/xenolinux-2.4.25-sparse/arch/xen/kernel/time.c b/xenolinux-2.4.25-sparse/arch/xen/kernel/time.c
index 3674aef2ef..52920cd0fc 100644
--- a/xenolinux-2.4.25-sparse/arch/xen/kernel/time.c
+++ b/xenolinux-2.4.25-sparse/arch/xen/kernel/time.c
@@ -492,8 +492,7 @@ static inline void do_timer_interrupt(int irq, void *dev_id,
 static void timer_interrupt(int irq, void *dev_id, struct pt_regs *regs)
 {
     write_lock(&xtime_lock);
-    while ( !TIME_VALUES_UP_TO_DATE )
-        do_timer_interrupt(irq, NULL, regs);
+    do_timer_interrupt(irq, NULL, regs);
     write_unlock(&xtime_lock);
 }
 
diff --git a/xenolinux-2.4.25-sparse/include/asm-xen/system.h b/xenolinux-2.4.25-sparse/include/asm-xen/system.h
index 40e11d3e68..6a8e352ac5 100644
--- a/xenolinux-2.4.25-sparse/include/asm-xen/system.h
+++ b/xenolinux-2.4.25-sparse/include/asm-xen/system.h
@@ -351,9 +351,13 @@ do {                                                                          \
 
 #define __save_and_sti(x)                                                     \
 do {                                                                          \
+    shared_info_t *_shared = HYPERVISOR_shared_info;                          \
     barrier();                                                                \
-    (x) = HYPERVISOR_shared_info->vcpu_data[0].evtchn_upcall_mask;            \
-    HYPERVISOR_shared_info->vcpu_data[0].evtchn_upcall_mask = 0;              \
+    (x) = _shared->vcpu_data[0].evtchn_upcall_mask;                           \
+    _shared->vcpu_data[0].evtchn_upcall_mask = 0;                             \
+    barrier(); /* unmask then check (avoid races) */                          \
+    if ( unlikely(_shared->vcpu_data[0].evtchn_upcall_pending) )              \
+        evtchn_do_upcall(NULL);                                               \
 } while (0)
 
 #define local_irq_save(x)       __save_and_cli(x)