[PATCH] s390 (5/19): system tick misaccounting.
From: Martin Schwidefsky
Date: Thu Sep 25 2003 - 12:24:39 EST
Fix system tick misaccounting problem.
diffstat:
arch/s390/kernel/entry.S | 26 ++++----------------------
arch/s390/kernel/entry64.S | 26 ++++----------------------
arch/s390/kernel/s390_ext.c | 28 +++++++++++++++++++++++-----
arch/s390/kernel/time.c | 21 ++++++++++-----------
drivers/s390/block/dasd_diag.c | 4 +---
drivers/s390/char/sclp.c | 2 --
drivers/s390/cio/cio.c | 6 ++++--
include/asm-s390/hardirq.h | 1 +
include/asm-s390/lowcore.h | 8 ++++++--
9 files changed, 53 insertions(+), 69 deletions(-)
diff -urN linux-2.6/arch/s390/kernel/entry.S linux-2.6-s390/arch/s390/kernel/entry.S
--- linux-2.6/arch/s390/kernel/entry.S Thu Sep 25 18:33:25 2003
+++ linux-2.6-s390/arch/s390/kernel/entry.S Thu Sep 25 18:33:25 2003
@@ -515,12 +515,9 @@
SAVE_ALL_BASE
SAVE_ALL __LC_IO_OLD_PSW,0
GET_THREAD_INFO # load pointer to task_struct to R9
+ stck __LC_INT_CLOCK
l %r1,BASED(.Ldo_IRQ) # load address of do_IRQ
la %r2,SP_PTREGS(%r15) # address of register-save area
- sr %r3,%r3
- icm %r3,3,__LC_SUBCHANNEL_NR # load subchannel nr & extend to int
- l %r4,__LC_IO_INT_PARM # load interruption parm
- l %r5,__LC_IO_INT_WORD # load interruption word
basr %r14,%r1 # branch to standard irq handler
io_return:
@@ -609,26 +606,11 @@
SAVE_ALL_BASE
SAVE_ALL __LC_EXT_OLD_PSW,0
GET_THREAD_INFO # load pointer to task_struct to R9
+ stck __LC_INT_CLOCK
+ la %r2,SP_PTREGS(%r15) # address of register-save area
+ lh %r3,__LC_EXT_INT_CODE # get interruption code
l %r1,BASED(.Ldo_extint)
basr %r14,%r1
- lh %r6,__LC_EXT_INT_CODE # get interruption code
- lr %r1,%r6 # calculate index = code & 0xff
- n %r1,BASED(.Lc0xff)
- sll %r1,2
- l %r7,BASED(.Lext_hash)
- l %r7,0(%r1,%r7) # get first list entry for hash value
- ltr %r7,%r7 # == NULL ?
- bz BASED(io_return) # yes, nothing to do, exit
-ext_int_loop:
- ch %r6,8(%r7) # compare external interrupt code
- bne BASED(ext_int_next)
- l %r1,4(%r7) # get handler address
- la %r2,SP_PTREGS(%r15) # address of register-save area
- lr %r3,%r6 # interruption code
- basr %r14,%r1 # call handler
-ext_int_next:
- icm %r7,15,0(%r7) # next list entry
- bnz BASED(ext_int_loop)
b BASED(io_return)
/*
diff -urN linux-2.6/arch/s390/kernel/entry64.S linux-2.6-s390/arch/s390/kernel/entry64.S
--- linux-2.6/arch/s390/kernel/entry64.S Thu Sep 25 18:33:25 2003
+++ linux-2.6-s390/arch/s390/kernel/entry64.S Thu Sep 25 18:33:25 2003
@@ -552,10 +552,8 @@
io_int_handler:
SAVE_ALL __LC_IO_OLD_PSW,0
GET_THREAD_INFO # load pointer to task_struct to R9
+ stck __LC_INT_CLOCK
la %r2,SP_PTREGS(%r15) # address of register-save area
- llgh %r3,__LC_SUBCHANNEL_NR # load subchannel number
- llgf %r4,__LC_IO_INT_PARM # load interruption parm
- llgf %r5,__LC_IO_INT_WORD # load interruption word
brasl %r14,do_IRQ # call standard irq handler
io_return:
@@ -640,26 +638,10 @@
ext_int_handler:
SAVE_ALL __LC_EXT_OLD_PSW,0
GET_THREAD_INFO # load pointer to task_struct to R9
- brasl %r14,do_extint
- llgh %r6,__LC_EXT_INT_CODE # get interruption code
- lgr %r1,%r6 # calculate index = code & 0xff
- nill %r1,0xff
- sll %r1,3
- larl %r7,ext_int_hash
- lg %r7,0(%r1,%r7) # get first list entry for hash value
- ltgr %r7,%r7 # == NULL ?
- jz io_return # yes, nothing to do, exit
-ext_int_loop:
- ch %r6,16(%r7) # compare external interrupt code
- jne ext_int_next
- lg %r1,8(%r7) # get handler address
+ stck __LC_INT_CLOCK
la %r2,SP_PTREGS(%r15) # address of register-save area
- lgr %r3,%r6 # interruption code
- basr %r14,%r1 # call handler
-ext_int_next:
- lg %r7,0(%r7) # next list entry
- ltgr %r7,%r7
- jnz ext_int_loop
+ llgh %r3,__LC_EXT_INT_CODE # get interruption code
+ brasl %r14,do_extint
j io_return
/*
diff -urN linux-2.6/arch/s390/kernel/s390_ext.c linux-2.6-s390/arch/s390/kernel/s390_ext.c
--- linux-2.6/arch/s390/kernel/s390_ext.c Mon Sep 8 21:50:03 2003
+++ linux-2.6-s390/arch/s390/kernel/s390_ext.c Thu Sep 25 18:33:25 2003
@@ -26,7 +26,8 @@
*/
ext_int_info_t *ext_int_hash[256] = { 0, };
-int register_external_interrupt(__u16 code, ext_int_handler_t handler) {
+int register_external_interrupt(__u16 code, ext_int_handler_t handler)
+{
ext_int_info_t *p;
int index;
@@ -42,7 +43,8 @@
}
int register_early_external_interrupt(__u16 code, ext_int_handler_t handler,
- ext_int_info_t *p) {
+ ext_int_info_t *p)
+{
int index;
if (p == NULL)
@@ -55,7 +57,8 @@
return 0;
}
-int unregister_external_interrupt(__u16 code, ext_int_handler_t handler) {
+int unregister_external_interrupt(__u16 code, ext_int_handler_t handler)
+{
ext_int_info_t *p, *q;
int index;
@@ -79,7 +82,8 @@
}
int unregister_early_external_interrupt(__u16 code, ext_int_handler_t handler,
- ext_int_info_t *p) {
+ ext_int_info_t *p)
+{
ext_int_info_t *q;
int index;
@@ -101,9 +105,23 @@
return 0;
}
-void do_extint(void)
+void do_extint(struct pt_regs *regs, unsigned short code)
{
+ ext_int_info_t *p;
+ int index;
+
+ irq_enter();
+ if (S390_lowcore.int_clock >= S390_lowcore.jiffy_timer)
+ account_ticks(regs);
kstat_cpu(smp_processor_id()).irqs[EXTERNAL_INTERRUPT]++;
+ index = code & 0xff;
+ for (p = ext_int_hash[index]; p; p = p->next) {
+ if (likely(p->code == code)) {
+ if (likely(p->handler))
+ p->handler(regs, code);
+ }
+ }
+ irq_exit();
}
EXPORT_SYMBOL(register_external_interrupt);
diff -urN linux-2.6/arch/s390/kernel/time.c linux-2.6-s390/arch/s390/kernel/time.c
--- linux-2.6/arch/s390/kernel/time.c Thu Sep 25 18:33:22 2003
+++ linux-2.6-s390/arch/s390/kernel/time.c Thu Sep 25 18:33:25 2003
@@ -166,28 +166,29 @@
* timer_interrupt() needs to keep up the real-time clock,
* as well as call the "do_timer()" routine every clocktick
*/
-static void do_comparator_interrupt(struct pt_regs *regs, __u16 error_code)
+void account_ticks(struct pt_regs *regs)
{
__u64 tmp;
__u32 ticks;
/* Calculate how many ticks have passed. */
- tmp = get_clock() - S390_lowcore.jiffy_timer;
- if (tmp >= 2*CLK_TICKS_PER_JIFFY) { /* more than one tick ? */
- ticks = __calculate_ticks(tmp);
+ tmp = S390_lowcore.int_clock - S390_lowcore.jiffy_timer;
+ if (tmp >= 2*CLK_TICKS_PER_JIFFY) { /* more than two ticks ? */
+ ticks = __calculate_ticks(tmp) + 1;
S390_lowcore.jiffy_timer +=
CLK_TICKS_PER_JIFFY * (__u64) ticks;
+ } else if (tmp >= CLK_TICKS_PER_JIFFY) {
+ ticks = 2;
+ S390_lowcore.jiffy_timer += 2*CLK_TICKS_PER_JIFFY;
} else {
ticks = 1;
S390_lowcore.jiffy_timer += CLK_TICKS_PER_JIFFY;
}
/* set clock comparator for next tick */
- tmp = S390_lowcore.jiffy_timer + CLK_TICKS_PER_JIFFY + CPU_DEVIATION;
+ tmp = S390_lowcore.jiffy_timer + CPU_DEVIATION;
asm volatile ("SCKC %0" : : "m" (tmp));
- irq_enter();
-
#ifdef CONFIG_SMP
/*
* Do not rely on the boot cpu to do the calls to do_timer.
@@ -215,8 +216,6 @@
while (ticks--)
do_timer(regs);
#endif
-
- irq_exit();
}
/*
@@ -228,7 +227,7 @@
__u64 timer;
timer = jiffies_timer_cc + jiffies_64 * CLK_TICKS_PER_JIFFY;
- S390_lowcore.jiffy_timer = timer;
+ S390_lowcore.jiffy_timer = timer + CLK_TICKS_PER_JIFFY;
timer += CLK_TICKS_PER_JIFFY + CPU_DEVIATION;
asm volatile ("SCKC %0" : : "m" (timer));
/* allow clock comparator timer interrupt */
@@ -275,7 +274,7 @@
-xtime.tv_sec, -xtime.tv_nsec);
/* request the 0x1004 external interrupt */
- if (register_early_external_interrupt(0x1004, do_comparator_interrupt,
+ if (register_early_external_interrupt(0x1004, 0,
&ext_int_info_timer) != 0)
panic("Couldn't request external interrupt 0x1004");
diff -urN linux-2.6/drivers/s390/block/dasd_diag.c linux-2.6-s390/drivers/s390/block/dasd_diag.c
--- linux-2.6/drivers/s390/block/dasd_diag.c Mon Sep 8 21:49:51 2003
+++ linux-2.6-s390/drivers/s390/block/dasd_diag.c Thu Sep 25 18:33:25 2003
@@ -6,7 +6,7 @@
* Bugreports.to..: <Linux390@xxxxxxxxxx>
* (C) IBM Corporation, IBM Deutschland Entwicklung GmbH, 1999,2000
*
- * $Revision: 1.31 $
+ * $Revision: 1.32 $
*/
#include <linux/config.h>
@@ -170,7 +170,6 @@
ip = S390_lowcore.ext_params;
cpu = smp_processor_id();
- irq_enter();
if (!ip) { /* no intparm: unsolicited interrupt */
MESSAGE(KERN_DEBUG, "%s", "caught unsolicited interrupt");
@@ -218,7 +217,6 @@
dasd_schedule_bh(device);
spin_unlock_irqrestore(get_ccwdev_lock(device->cdev), flags);
- irq_exit();
}
static int
diff -urN linux-2.6/drivers/s390/char/sclp.c linux-2.6-s390/drivers/s390/char/sclp.c
--- linux-2.6/drivers/s390/char/sclp.c Mon Sep 8 21:50:08 2003
+++ linux-2.6-s390/drivers/s390/char/sclp.c Thu Sep 25 18:33:25 2003
@@ -293,7 +293,6 @@
finished_sccb = ext_int_param & EXT_INT_SCCB_MASK;
evbuf_pending = ext_int_param & (EXT_INT_EVBUF_PENDING |
EXT_INT_STATECHANGE_PENDING);
- irq_enter();
req = NULL;
if (finished_sccb != 0U) {
list_for_each(l, &sclp_req_queue) {
@@ -321,7 +320,6 @@
spin_unlock(&sclp_lock);
/* and start next request on the queue */
sclp_start_request();
- irq_exit();
}
/*
diff -urN linux-2.6/drivers/s390/cio/cio.c linux-2.6-s390/drivers/s390/cio/cio.c
--- linux-2.6/drivers/s390/cio/cio.c Thu Sep 25 18:33:23 2003
+++ linux-2.6-s390/drivers/s390/cio/cio.c Thu Sep 25 18:33:25 2003
@@ -588,13 +588,15 @@
*
*/
void
-do_IRQ (struct pt_regs regs)
+do_IRQ (struct pt_regs *regs)
{
struct tpi_info *tpi_info;
struct subchannel *sch;
struct irb *irb;
irq_enter ();
+ if (S390_lowcore.int_clock >= S390_lowcore.jiffy_timer)
+ account_ticks(regs);
/*
* Get interrupt information from lowcore
*/
@@ -663,7 +665,7 @@
do {
spin_unlock(&console_subchannel.lock);
if (!cio_tpi())
- udelay (100);
+ cpu_relax();
spin_lock(&console_subchannel.lock);
} while (console_subchannel.schib.scsw.actl != 0);
/*
diff -urN linux-2.6/include/asm-s390/hardirq.h linux-2.6-s390/include/asm-s390/hardirq.h
--- linux-2.6/include/asm-s390/hardirq.h Thu Sep 25 18:33:25 2003
+++ linux-2.6-s390/include/asm-s390/hardirq.h Thu Sep 25 18:33:25 2003
@@ -87,6 +87,7 @@
extern void do_call_softirq(void);
+extern void account_ticks(struct pt_regs *);
#define invoke_softirq() do_call_softirq()
diff -urN linux-2.6/include/asm-s390/lowcore.h linux-2.6-s390/include/asm-s390/lowcore.h
--- linux-2.6/include/asm-s390/lowcore.h Thu Sep 25 18:33:25 2003
+++ linux-2.6-s390/include/asm-s390/lowcore.h Thu Sep 25 18:33:25 2003
@@ -66,6 +66,7 @@
#define __LC_IPLDEV 0xC7C
#define __LC_JIFFY_TIMER 0xC80
#define __LC_CURRENT 0xC90
+#define __LC_INT_CLOCK 0xC98
#else /* __s390x__ */
#define __LC_KERNEL_STACK 0xD40
#define __LC_ASYNC_STACK 0xD48
@@ -74,6 +75,7 @@
#define __LC_IPLDEV 0xDB8
#define __LC_JIFFY_TIMER 0xDC0
#define __LC_CURRENT 0xDD8
+#define __LC_INT_CLOCK 0xDE8
#endif /* __s390x__ */
#define __LC_PANIC_MAGIC 0xE00
@@ -174,7 +176,8 @@
__u32 percpu_offset; /* 0xc8c */
__u32 current_task; /* 0xc90 */
__u32 softirq_pending; /* 0xc94 */
- __u8 pad11[0xe00-0xc98]; /* 0xc98 */
+ __u64 int_clock; /* 0xc98 */
+ __u8 pad11[0xe00-0xca0]; /* 0xca0 */
/* 0xe00 is used as indicator for dump tools */
/* whether the kernel died with panic() or not */
@@ -252,7 +255,8 @@
__u64 percpu_offset; /* 0xdd0 */
__u64 current_task; /* 0xdd8 */
__u64 softirq_pending; /* 0xde0 */
- __u8 pad12[0xe00-0xde8]; /* 0xde8 */
+ __u64 int_clock; /* 0xde8 */
+ __u8 pad12[0xe00-0xdf0]; /* 0xdf0 */
/* 0xe00 is used as indicator for dump tools */
/* whether the kernel died with panic() or not */
-
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