[PATCH] syscall latency improvement #1

From: David Howells <dhowells@redhat.com>
To: torvalds@transmeta.com
Cc: linux-kernel@vger.kernel.org, dhowells@redhat.com
Subject: [PATCH] syscall latency improvement #1
Date: Fri, 25 Jan 2002 18:54:02 +0000	[thread overview]
Message-ID: <18993.1011984842@warthog.cambridge.redhat.com> (raw)


Hi Linus,

The attached patch does the following to 2.5.3-pre5:

 * consolidates various status items that are found in the lower reaches of
   task_struct into one 32-bit word, thus allowing them to be tested
   atomically without the need to disable interrupts in entry.S.

 * optimises the instructions in the system_call path in entry.S

 * frees up a hole in the bottom part of the task_struct (on the 1st cache
   line).

 * improves base syscall latency by approximately 5.4% (dual PIII) or 3.6%
   (dual Athlon) as measured by lmbench's "lat_syscall null" command against
   the vanilla kernel.

Most notable are the changes to the following files:

	arch/i386/kernel/entry.S
	include/linux/sched.h

David

diff -uNr linux-2.5.3-pre5/arch/i386/kernel/entry.S linux-work-253p5/arch/i386/kernel/entry.S

--- linux-2.5.3-pre5/arch/i386/kernel/entry.S	Tue Jan 22 09:06:49 2002
+++ linux-work-253p5/arch/i386/kernel/entry.S	Fri Jan 25 15:01:07 2002
@@ -72,10 +72,13 @@
  */
 state		=  0
 flags		=  4
-sigpending	=  8
+work		=  8
+need_resched	= work+0
+syscall_trace	= work+1
+sigpending	= work+2
+notify_resume	= work+3
 addr_limit	= 12
 exec_domain	= 16
-need_resched	= 20
 tsk_ptrace	= 24
 processor	= 52
 
@@ -151,7 +154,7 @@
 	call *%edx
 	addl $4, %esp
 	popl %eax
-	jmp ret_from_sys_call
+	jmp resume_userspace
 
 ENTRY(lcall27)
 	pushfl			# We get a different stack layout with call gates,
@@ -172,7 +175,7 @@
 	call *%edx
 	addl $4, %esp
 	popl %eax
-	jmp ret_from_sys_call
+	jmp resume_userspace
 
 
 ENTRY(ret_from_fork)
@@ -180,9 +183,7 @@
 	call SYMBOL_NAME(schedule_tail)
 	addl $4, %esp
 	GET_CURRENT(%ebx)
-	testb $0x02,tsk_ptrace(%ebx)	# PT_TRACESYS
-	jne tracesys_exit
-	jmp	ret_from_sys_call
+	jmp syscall_exit
 
 /*
  * Return to user mode is not as complex as all this looks,
@@ -191,73 +192,99 @@
  * less clear than it otherwise should be.
  */
 
+	# userspace resumption stub bypassing syscall exit tracing
+	ALIGN
+ENTRY(ret_from_intr)
+	GET_CURRENT(%ebx)
+ret_from_exception:
+	movl EFLAGS(%esp),%eax		# mix EFLAGS and CS
+	movb CS(%esp),%al
+	testl $(VM_MASK | 3),%eax
+	jz restore_all			# returning to kernel-space or vm86-space
+	sti				# we may have come from an interrupt handler
+ENTRY(resume_userspace)
+	movl work(%ebx),%ecx
+	andl $0xffff00ff,%ecx		# current->work (ignoring syscall_trace)
+	jne work_pending
+	jmp restore_all
+
+	# system call handler stub
+	ALIGN
 ENTRY(system_call)
 	pushl %eax			# save orig_eax
 	SAVE_ALL
 	GET_CURRENT(%ebx)
-	testb $0x02,tsk_ptrace(%ebx)	# PT_TRACESYS
-	jne tracesys
 	cmpl $(NR_syscalls),%eax
-	jae badsys
+	jae syscall_badsys
+	testb $0xff,syscall_trace(%ebx)	# system call tracing in operation
+	jnz syscall_trace_entry
+syscall_traced:
 	call *SYMBOL_NAME(sys_call_table)(,%eax,4)
-	movl %eax,EAX(%esp)		# save the return value
-ENTRY(ret_from_sys_call)
-	cli				# need_resched and signals atomic test
-	cmpl $0,need_resched(%ebx)
-	jne reschedule
-	cmpl $0,sigpending(%ebx)
-	jne signal_return
+	movl %eax,EAX(%esp)			# store the return value
+syscall_exit:
+	movl work(%ebx),%ecx
+	testl %ecx,%ecx				# current->work
+	jne syscall_exit_work
 restore_all:
 	RESTORE_ALL
 
+	# perform work that needs to be done immediately before resumption
 	ALIGN
-signal_return:
-	sti				# we can get here from an interrupt handler
+work_pending:
+	testb %cl,%cl			# current->work.need_resched
+	jz work_notifysig
+work_resched:
+	call SYMBOL_NAME(schedule)
+	movl work(%ebx),%ecx
+	andl $0xffff00ff,%ecx		# ignore the syscall trace counter
+	jz restore_all
+	testb %cl,%cl			# current->work.need_resched
+	jnz work_resched
+
+work_notifysig:				# deal with pending signals and notify-resume requests
 	testl $(VM_MASK),EFLAGS(%esp)
 	movl %esp,%eax
-	jne v86_signal_return
+	jne work_notifysig_v86		# returning to kernel-space or vm86-space
 	xorl %edx,%edx
-	call SYMBOL_NAME(do_signal)
+	call SYMBOL_NAME(do_notify_resume)
 	jmp restore_all
 
 	ALIGN
-v86_signal_return:
+work_notifysig_v86:
+	pushl %ecx
 	call SYMBOL_NAME(save_v86_state)
+	popl %ecx
 	movl %eax,%esp
 	xorl %edx,%edx
-	call SYMBOL_NAME(do_signal)
+	call SYMBOL_NAME(do_notify_resume)
 	jmp restore_all
 
+	# perform syscall exit tracing
 	ALIGN
-tracesys:
+syscall_trace_entry:
 	movl $-ENOSYS,EAX(%esp)
-	call SYMBOL_NAME(syscall_trace)
+	movl %esp,%eax
+	xorl %edx,%edx
+	call SYMBOL_NAME(do_syscall_trace)
 	movl ORIG_EAX(%esp),%eax
 	cmpl $(NR_syscalls),%eax
-	jae tracesys_exit
-	call *SYMBOL_NAME(sys_call_table)(,%eax,4)
-	movl %eax,EAX(%esp)		# save the return value
-tracesys_exit:
-	call SYMBOL_NAME(syscall_trace)
-	jmp ret_from_sys_call
-badsys:
-	movl $-ENOSYS,EAX(%esp)
-	jmp ret_from_sys_call
+	jnae syscall_traced
+	jmp syscall_exit
 
+	# perform syscall exit tracing
 	ALIGN
-ENTRY(ret_from_intr)
-	GET_CURRENT(%ebx)
-ret_from_exception:
-	movl EFLAGS(%esp),%eax		# mix EFLAGS and CS
-	movb CS(%esp),%al
-	testl $(VM_MASK | 3),%eax	# return to VM86 mode or non-supervisor?
-	jne ret_from_sys_call
-	jmp restore_all
+syscall_exit_work:
+	testb %ch,%ch				# current->work.syscall_trace
+	jz work_pending
+	movl %esp,%eax
+	movl $1,%edx
+	call SYMBOL_NAME(do_syscall_trace)
+	jmp resume_userspace
 
 	ALIGN
-reschedule:
-	call SYMBOL_NAME(schedule)    # test
-	jmp ret_from_sys_call
+syscall_badsys:
+	movl $-ENOSYS,EAX(%esp)
+	jmp resume_userspace
 
 ENTRY(divide_error)
 	pushl $0		# no error code
diff -uNr linux-2.5.3-pre5/arch/i386/kernel/process.c linux-work-253p5/arch/i386/kernel/process.c
--- linux-2.5.3-pre5/arch/i386/kernel/process.c	Fri Jan 25 14:52:14 2002
+++ linux-work-253p5/arch/i386/kernel/process.c	Fri Jan 25 15:01:07 2002
@@ -89,7 +89,7 @@
 
 /*
  * On SMP it's slightly faster (but much more power-consuming!)
- * to poll the ->need_resched flag instead of waiting for the
+ * to poll the ->work.need_resched flag instead of waiting for the
  * cross-CPU IPI to arrive. Use this option with caution.
  */
 static void poll_idle (void)
@@ -102,15 +102,15 @@
 	 * Deal with another CPU just having chosen a thread to
 	 * run here:
 	 */
-	oldval = xchg(&current->need_resched, -1);
+	oldval = xchg(&current->work.need_resched, -1);
 
 	if (!oldval)
 		asm volatile(
 			"2:"
-			"cmpl $-1, %0;"
+			"cmpb $-1, %0;"
 			"rep; nop;"
 			"je 2b;"
-				: :"m" (current->need_resched));
+				: :"m" (current->work.need_resched));
 }
 
 /*
diff -uNr linux-2.5.3-pre5/arch/i386/kernel/ptrace.c linux-work-253p5/arch/i386/kernel/ptrace.c
--- linux-2.5.3-pre5/arch/i386/kernel/ptrace.c	Tue Jan 22 09:06:49 2002
+++ linux-work-253p5/arch/i386/kernel/ptrace.c	Fri Jan 25 15:01:07 2002
@@ -277,10 +277,18 @@
 		ret = -EIO;
 		if ((unsigned long) data > _NSIG)
 			break;
-		if (request == PTRACE_SYSCALL)
-			child->ptrace |= PT_TRACESYS;
-		else
-			child->ptrace &= ~PT_TRACESYS;
+		if (request == PTRACE_SYSCALL) {
+			if (!(child->ptrace & PT_SYSCALLTRACE)) {
+				child->ptrace |= PT_SYSCALLTRACE;
+				child->work.syscall_trace++;
+			}
+		}
+		else {
+			if (child->ptrace & PT_SYSCALLTRACE) {
+				child->ptrace &= ~PT_SYSCALLTRACE;
+				child->work.syscall_trace--;
+			}
+		}
 		child->exit_code = data;
 	/* make sure the single step bit is not set. */
 		tmp = get_stack_long(child, EFL_OFFSET) & ~TRAP_FLAG;
@@ -315,7 +323,10 @@
 		ret = -EIO;
 		if ((unsigned long) data > _NSIG)
 			break;
-		child->ptrace &= ~PT_TRACESYS;
+		if (child->ptrace & PT_SYSCALLTRACE) {
+			child->ptrace &= ~PT_SYSCALLTRACE;
+			child->work.syscall_trace--;
+		}
 		if ((child->ptrace & PT_DTRACE) == 0) {
 			/* Spurious delayed TF traps may occur */
 			child->ptrace |= PT_DTRACE;
@@ -439,10 +450,14 @@
 	return ret;
 }
 
-asmlinkage void syscall_trace(void)
+/* notification of system call entry/exit
+ * - triggered by current->work.syscall_trace
+ */
+__attribute__((regparm(3)))
+void do_syscall_trace(struct pt_regs *regs, int entryexit)
 {
-	if ((current->ptrace & (PT_PTRACED|PT_TRACESYS)) !=
-			(PT_PTRACED|PT_TRACESYS))
+	if ((current->ptrace & (PT_PTRACED|PT_SYSCALLTRACE)) !=
+	    (PT_PTRACED|PT_SYSCALLTRACE))
 		return;
 	/* the 0x80 provides a way for the tracing parent to distinguish
 	   between a syscall stop and SIGTRAP delivery */
@@ -461,3 +476,15 @@
 		current->exit_code = 0;
 	}
 }
+
+/* notification of userspace execution resumption
+ * - triggered by current->work.notify_resume
+ */
+__attribute__((regparm(3)))
+void do_notify_resume(struct pt_regs *regs, sigset_t *oldset,
+		      struct task_work work_pending)
+{
+	/* deal with pending signal delivery */
+	if (work_pending.sigpending)
+		do_signal(regs,oldset);
+}
diff -uNr linux-2.5.3-pre5/arch/i386/kernel/signal.c linux-work-253p5/arch/i386/kernel/signal.c
--- linux-2.5.3-pre5/arch/i386/kernel/signal.c	Tue Jan 22 09:06:49 2002
+++ linux-work-253p5/arch/i386/kernel/signal.c	Fri Jan 25 15:01:07 2002
@@ -28,8 +28,6 @@
 
 #define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP)))
 
-int FASTCALL(do_signal(struct pt_regs *regs, sigset_t *oldset));
-
 int copy_siginfo_to_user(siginfo_t *to, siginfo_t *from)
 {
 	if (!access_ok (VERIFY_WRITE, to, sizeof(siginfo_t)))
diff -uNr linux-2.5.3-pre5/arch/i386/kernel/vm86.c linux-work-253p5/arch/i386/kernel/vm86.c
--- linux-2.5.3-pre5/arch/i386/kernel/vm86.c	Tue Jan 22 09:06:49 2002
+++ linux-work-253p5/arch/i386/kernel/vm86.c	Fri Jan 25 15:01:07 2002
@@ -212,7 +212,7 @@
 	info->regs.__null_ds = 0;
 	info->regs.__null_es = 0;
 
-/* we are clearing fs,gs later just before "jmp ret_from_sys_call",
+/* we are clearing fs,gs later just before "jmp resume_userspace",
  * because starting with Linux 2.1.x they aren't no longer saved/restored
  */
 
@@ -255,7 +255,7 @@
 	__asm__ __volatile__(
 		"xorl %%eax,%%eax; movl %%eax,%%fs; movl %%eax,%%gs\n\t"
 		"movl %0,%%esp\n\t"
-		"jmp ret_from_sys_call"
+		"jmp resume_userspace"
 		: /* no outputs */
 		:"r" (&info->regs), "b" (tsk) : "ax");
 	/* we never return here */
@@ -268,7 +268,7 @@
 	regs32 = save_v86_state(regs16);
 	regs32->eax = retval;
 	__asm__ __volatile__("movl %0,%%esp\n\t"
-		"jmp ret_from_sys_call"
+		"jmp resume_userspace"
 		: : "r" (regs32), "b" (current));
 }
 
diff -uNr linux-2.5.3-pre5/fs/lockd/svc.c linux-work-253p5/fs/lockd/svc.c
--- linux-2.5.3-pre5/fs/lockd/svc.c	Tue Jan 22 09:05:58 2002
+++ linux-work-253p5/fs/lockd/svc.c	Fri Jan 25 15:01:07 2002
@@ -304,7 +304,7 @@
 	 * Wait for the lockd process to exit, but since we're holding
 	 * the lockd semaphore, we can't wait around forever ...
 	 */
-	current->sigpending = 0;
+	current->work.sigpending = 0;
 	interruptible_sleep_on_timeout(&lockd_exit, HZ);
 	if (nlmsvc_pid) {
 		printk(KERN_WARNING 
diff -uNr linux-2.5.3-pre5/fs/nfsd/export.c linux-work-253p5/fs/nfsd/export.c
--- linux-2.5.3-pre5/fs/nfsd/export.c	Tue Jan 22 09:05:58 2002
+++ linux-work-253p5/fs/nfsd/export.c	Fri Jan 25 15:01:07 2002
@@ -468,7 +468,7 @@
 		return 0;
 	}
 
-	current->sigpending = 0;
+	current->work.sigpending = 0;
 	want_lock++;
 	while (hash_count || hash_lock) {
 		interruptible_sleep_on(&hash_wait);
diff -uNr linux-2.5.3-pre5/include/asm-i386/signal.h linux-work-253p5/include/asm-i386/signal.h
--- linux-2.5.3-pre5/include/asm-i386/signal.h	Thu Jan 24 14:53:26 2002
+++ linux-work-253p5/include/asm-i386/signal.h	Fri Jan 25 15:05:45 2002
@@ -2,6 +2,7 @@
 #define _ASMi386_SIGNAL_H
 
 #include <linux/types.h>
+#include <linux/linkage.h>
 
 /* Avoid too many header ordering problems.  */
 struct siginfo;
@@ -216,6 +217,8 @@
 	return word;
 }
 
+extern int FASTCALL(do_signal(struct pt_regs *regs, sigset_t *oldset));
+
 #endif /* __KERNEL__ */
 
 #endif
diff -uNr linux-2.5.3-pre5/include/linux/init_task.h linux-work-253p5/include/linux/init_task.h
--- linux-2.5.3-pre5/include/linux/init_task.h	Fri Jan 25 14:52:17 2002
+++ linux-work-253p5/include/linux/init_task.h	Fri Jan 25 15:12:17 2002
@@ -35,6 +35,14 @@
 	siglock:	SPIN_LOCK_UNLOCKED 		\
 }
 
+#define INIT_TASK_WORK				\
+{						\
+	need_resched:	0,			\
+	syscall_trace:	0,			\
+	sigpending:	0,			\
+	notify_resume:	0,			\
+}
+
 /*
  *  INIT_TASK is used to set up the first task table, touch at
  * your own risk!. Base=0, limit=0x1fffff (=2MB)
@@ -43,7 +51,7 @@
 {									\
     state:		0,						\
     flags:		0,						\
-    sigpending:		0,						\
+    work:		INIT_TASK_WORK,					\
     addr_limit:		KERNEL_DS,					\
     exec_domain:	&default_exec_domain,				\
     lock_depth:		-1,						\
diff -uNr linux-2.5.3-pre5/include/linux/sched.h linux-work-253p5/include/linux/sched.h
--- linux-2.5.3-pre5/include/linux/sched.h	Fri Jan 25 14:52:17 2002
+++ linux-work-253p5/include/linux/sched.h	Fri Jan 25 15:05:45 2002
@@ -228,19 +228,29 @@
 
 typedef struct prio_array prio_array_t;
 
+/* this struct must occupy one 32-bit chunk so that is can be read in one go */
+struct task_work {
+	__s8	need_resched;
+	__u8	syscall_trace;	/* count of syscall interceptors */
+	__u8	sigpending;
+	__u8	notify_resume;	/* request for notification on
+				   userspace execution resumption */
+} __attribute__((packed));
+
 struct task_struct {
 	/*
 	 * offsets of these are hardcoded elsewhere - touch with care
 	 */
 	volatile long state;	/* -1 unrunnable, 0 runnable, >0 stopped */
 	unsigned long flags;	/* per process flags, defined below */
-	int sigpending;
+	volatile struct task_work work;
+
 	mm_segment_t addr_limit;	/* thread address space:
 					 	0-0xBFFFFFFF for user-thead
 						0-0xFFFFFFFF for kernel-thread
 					 */
 	struct exec_domain *exec_domain;
-	volatile long need_resched;
+	long __pad;
 	unsigned long ptrace;
 
 	int lock_depth;		/* Lock depth */
@@ -381,7 +391,7 @@
  */
 
 #define PT_PTRACED	0x00000001
-#define PT_TRACESYS	0x00000002
+#define PT_SYSCALLTRACE	0x00000002	/* T if syscall_trace is +1 for ptrace() */
 #define PT_DTRACE	0x00000004	/* delayed trace (used on m68k, i386) */
 #define PT_TRACESYSGOOD	0x00000008
 #define PT_PTRACE_CAP	0x00000010	/* ptracer can follow suid-exec */
@@ -564,12 +574,12 @@
 
 static inline int signal_pending(struct task_struct *p)
 {
-	return (p->sigpending != 0);
+	return (p->work.sigpending != 0);
 }
   
 static inline int need_resched(void)
 {
-	return unlikely(current->need_resched != 0);
+	return unlikely(current->work.need_resched != 0);
 }
 
 static inline void cond_resched(void)
@@ -614,7 +624,7 @@
 
 static inline void recalc_sigpending(struct task_struct *t)
 {
-	t->sigpending = has_pending_signals(&t->pending.signal, &t->blocked);
+	t->work.sigpending = has_pending_signals(&t->pending.signal, &t->blocked);
 }
 
 /* True if we are on the alternate signal stack.  */
diff -uNr linux-2.5.3-pre5/kernel/fork.c linux-work-253p5/kernel/fork.c
--- linux-2.5.3-pre5/kernel/fork.c	Fri Jan 25 14:52:17 2002
+++ linux-work-253p5/kernel/fork.c	Fri Jan 25 15:01:07 2002
@@ -631,7 +631,7 @@
 	}
 	spin_lock_init(&p->alloc_lock);
 
-	p->sigpending = 0;
+	p->work.sigpending = 0;
 	init_sigpending(&p->pending);
 
 	p->it_real_value = p->it_virt_value = p->it_prof_value = 0;
@@ -756,7 +756,7 @@
 		 * Let the child process run first, to avoid most of the
 		 * COW overhead when the child exec()s afterwards.
 		 */
-		current->need_resched = 1;
+		current->work.need_resched = 1;
 
 fork_out:
 	return retval;
diff -uNr linux-2.5.3-pre5/kernel/sched.c linux-work-253p5/kernel/sched.c
--- linux-2.5.3-pre5/kernel/sched.c	Fri Jan 25 14:52:17 2002
+++ linux-work-253p5/kernel/sched.c	Fri Jan 25 15:01:07 2002
@@ -176,9 +176,9 @@
 {
 	int need_resched;
 
-	need_resched = p->need_resched;
+	need_resched = p->work.need_resched;
 	wmb();
-	p->need_resched = 1;
+	p->work.need_resched = 1;
 	if (!need_resched && (p->cpu != smp_processor_id()))
 		smp_send_reschedule(p->cpu);
 }
@@ -483,7 +483,7 @@
 	this_rq->nr_running++;
 	enqueue_task(next, this_rq->active);
 	if (next->prio < current->prio)
-		current->need_resched = 1;
+		current->work.need_resched = 1;
 	if (!idle && --imbalance) {
 		if (array == busiest->expired) {
 			array = busiest->active;
@@ -528,7 +528,7 @@
 		return idle_tick();
 	/* Task might have expired already, but not scheduled off yet */
 	if (p->array != rq->active) {
-		p->need_resched = 1;
+		p->work.need_resched = 1;
 		return;
 	}
 	spin_lock(&rq->lock);
@@ -539,7 +539,7 @@
 		 */
 		if ((p->policy == SCHED_RR) && !--p->time_slice) {
 			p->time_slice = NICE_TO_TIMESLICE(p->__nice);
-			p->need_resched = 1;
+			p->work.need_resched = 1;
 
 			/* put it at the end of the queue: */
 			dequeue_task(p, rq->active);
@@ -559,7 +559,7 @@
 		p->sleep_avg--;
 	if (!--p->time_slice) {
 		dequeue_task(p, rq->active);
-		p->need_resched = 1;
+		p->work.need_resched = 1;
 		p->prio = effective_prio(p);
 		p->time_slice = NICE_TO_TIMESLICE(p->__nice);
 		enqueue_task(p, TASK_INTERACTIVE(p) ? rq->active : rq->expired);
@@ -622,7 +622,7 @@
 	next = list_entry(queue->next, task_t, run_list);
 
 switch_tasks:
-	prev->need_resched = 0;
+	prev->work.need_resched = 0;
 
 	if (likely(prev != next)) {
 		rq->nr_switches++;
@@ -1246,7 +1246,7 @@
 	current->prio = MAX_PRIO;
 	current->state = TASK_RUNNING;
 	double_rq_unlock(this_rq, rq);
-	current->need_resched = 1;
+	current->work.need_resched = 1;
 	__restore_flags(flags);
 }
 
diff -uNr linux-2.5.3-pre5/kernel/signal.c linux-work-253p5/kernel/signal.c
--- linux-2.5.3-pre5/kernel/signal.c	Tue Jan 22 09:06:00 2002
+++ linux-work-253p5/kernel/signal.c	Fri Jan 25 15:01:07 2002
@@ -105,7 +105,7 @@
 void
 flush_signals(struct task_struct *t)
 {
-	t->sigpending = 0;
+	t->work.sigpending = 0;
 	flush_sigqueue(&t->pending);
 }
 
@@ -119,7 +119,7 @@
 		if (atomic_dec_and_test(&sig->count))
 			kmem_cache_free(sigact_cachep, sig);
 	}
-	tsk->sigpending = 0;
+	tsk->work.sigpending = 0;
 	flush_sigqueue(&tsk->pending);
 	spin_unlock_irq(&tsk->sigmask_lock);
 }
@@ -246,7 +246,7 @@
 		if (current->notifier) {
 			if (sigismember(current->notifier_mask, sig)) {
 				if (!(current->notifier)(current->notifier_data)) {
-					current->sigpending = 0;
+					current->work.sigpending = 0;
 					return 0;
 				}
 			}
@@ -465,7 +465,7 @@
  */
 static inline void signal_wake_up(struct task_struct *t)
 {
-	t->sigpending = 1;
+	t->work.sigpending = 1;
 
 #ifdef CONFIG_SMP
 	/*
diff -uNr linux-2.5.3-pre5/net/sunrpc/sched.c linux-work-253p5/net/sunrpc/sched.c
--- linux-2.5.3-pre5/net/sunrpc/sched.c	Fri Jan 25 14:52:17 2002
+++ linux-work-253p5/net/sunrpc/sched.c	Fri Jan 25 15:01:07 2002
@@ -1109,7 +1109,7 @@
 	unsigned long flags;
 
 	while (all_tasks) {
-		current->sigpending = 0;
+		current->work.sigpending = 0;
 		rpc_killall_tasks(NULL);
 		__rpc_schedule();
 		if (all_tasks) {
@@ -1183,7 +1183,7 @@
 	 * Usually rpciod will exit very quickly, so we
 	 * wait briefly before checking the process id.
 	 */
-	current->sigpending = 0;
+	current->work.sigpending = 0;
 	yield();
 	/*
 	 * Display a message if we're going to wait longer.
diff -uNr linux-2.5.3-pre5/net/sunrpc/svc.c linux-work-253p5/net/sunrpc/svc.c
--- linux-2.5.3-pre5/net/sunrpc/svc.c	Tue Jan 22 09:06:09 2002
+++ linux-work-253p5/net/sunrpc/svc.c	Fri Jan 25 15:01:08 2002
@@ -185,7 +185,7 @@
 		progp->pg_name, proto == IPPROTO_UDP? "udp" : "tcp", port);
 
 	if (!port)
-		current->sigpending = 0;
+		current->work.sigpending = 0;
 
 	for (i = 0; i < progp->pg_nvers; i++) {
 		if (progp->pg_vers[i] == NULL)
