diff -urNp --exclude CVS --exclude BitKeeper x-ref/arch/alpha/kernel/time.c x/arch/alpha/kernel/time.c
--- x-ref/arch/alpha/kernel/time.c 2003-06-13 22:07:23.000000000 +0200
+++ x/arch/alpha/kernel/time.c 2003-08-31 03:13:46.000000000 +0200
@@ -37,6 +37,7 @@
#include <linux/irq.h>
#include <linux/interrupt.h>
#include <linux/init.h>
+#include <linux/frlock.h>
#include <asm/uaccess.h>
#include <asm/io.h>
@@ -48,7 +49,7 @@
#include "proto.h"
#include "irq_impl.h"
-extern rwlock_t xtime_lock;
+extern frlock_t xtime_lock;
extern unsigned long wall_jiffies; /* kernel/timer.c */
static int set_rtc_mmss(unsigned long);
@@ -101,7 +102,7 @@ void timer_interrupt(int irq, void *dev,
alpha_do_profile(regs->pc);
#endif
- write_lock(&xtime_lock);
+ fr_write_lock(&xtime_lock);
/*
* Calculate how many ticks have passed since the last update,
@@ -133,7 +134,7 @@ void timer_interrupt(int irq, void *dev,
state.last_rtc_update = xtime.tv_sec - (tmp ? 600 : 0);
}
- write_unlock(&xtime_lock);
+ fr_write_unlock(&xtime_lock);
}
void
@@ -392,18 +393,19 @@ time_init(void)
void
do_gettimeofday(struct timeval *tv)
{
- unsigned long sec, usec, lost, flags;
+ unsigned long sec, usec, lost, seq;
unsigned long delta_cycles, delta_usec, partial_tick;
- read_lock_irqsave(&xtime_lock, flags);
+ do {
+ seq = fr_read_begin(&xtime_lock);
- delta_cycles = rpcc() - state.last_time;
- sec = xtime.tv_sec;
- usec = xtime.tv_usec;
- partial_tick = state.partial_tick;
- lost = jiffies - wall_jiffies;
+ delta_cycles = rpcc() - state.last_time;
+ sec = xtime.tv_sec;
+ usec = xtime.tv_usec;
+ partial_tick = state.partial_tick;
+ lost = jiffies - wall_jiffies;
- read_unlock_irqrestore(&xtime_lock, flags);
+ } while (seq != fr_read_end(&xtime_lock));
#ifdef CONFIG_SMP
/* Until and unless we figure out how to get cpu cycle counters
@@ -445,7 +447,7 @@ do_settimeofday(struct timeval *tv)
unsigned long delta_usec;
long sec, usec;
- write_lock_irq(&xtime_lock);
+ fr_write_lock_irq(&xtime_lock);
/* The offset that is added into time in do_gettimeofday above
must be subtracted out here to keep a coherent view of the
@@ -476,7 +478,7 @@ do_settimeofday(struct timeval *tv)
time_maxerror = NTP_PHASE_LIMIT;
time_esterror = NTP_PHASE_LIMIT;
- write_unlock_irq(&xtime_lock);
+ fr_write_unlock_irq(&xtime_lock);
}
diff -urNp --exclude CVS --exclude BitKeeper x-ref/arch/arm/kernel/time.c x/arch/arm/kernel/time.c
--- x-ref/arch/arm/kernel/time.c 2003-08-26 00:12:43.000000000 +0200
+++ x/arch/arm/kernel/time.c 2003-08-31 03:13:46.000000000 +0200
@@ -24,6 +24,7 @@
#include <linux/time.h>
#include <linux/init.h>
#include <linux/smp.h>
+#include <linux/frlock.h>
#include <asm/uaccess.h>
#include <asm/io.h>
@@ -33,7 +34,7 @@
#include <asm/hardware.h>
extern int setup_arm_irq(int, struct irqaction *);
-extern rwlock_t xtime_lock;
+extern frlock_t xtime_lock;
extern unsigned long wall_jiffies;
/* change this if you have some constant time drift */
@@ -151,20 +152,19 @@ static void do_leds(void)
void do_gettimeofday(struct timeval *tv)
{
- unsigned long flags;
+ unsigned long lost, seq;
unsigned long usec, sec;
- read_lock_irqsave(&xtime_lock, flags);
- usec = gettimeoffset();
- {
- unsigned long lost = jiffies - wall_jiffies;
+ do {
+ seq = fr_read_begin(&xtime_lock);
+ usec = gettimeoffset();
+ lost = jiffies - wall_jiffies;
if (lost)
usec += lost * USECS_PER_JIFFY;
- }
- sec = xtime.tv_sec;
- usec += xtime.tv_usec;
- read_unlock_irqrestore(&xtime_lock, flags);
+ sec = xtime.tv_sec;
+ usec += xtime.tv_usec;
+ } while (seq != fr_read_end(&xtime_lock));
/* usec may have gone up a lot: be safe */
while (usec >= 1000000) {
@@ -178,7 +178,7 @@ void do_gettimeofday(struct timeval *tv)
void do_settimeofday(struct timeval *tv)
{
- write_lock_irq(&xtime_lock);
+ fr_write_lock_irq(&xtime_lock);
/* This is revolting. We need to set the xtime.tv_usec
* correctly. However, the value in this location is
* is value at the last tick.
@@ -198,7 +198,7 @@ void do_settimeofday(struct timeval *tv)
time_status |= STA_UNSYNC;
time_maxerror = NTP_PHASE_LIMIT;
time_esterror = NTP_PHASE_LIMIT;
- write_unlock_irq(&xtime_lock);
+ fr_write_unlock_irq(&xtime_lock);
}
static struct irqaction timer_irq = {
diff -urNp --exclude CVS --exclude BitKeeper x-ref/arch/i386/kernel/time.c x/arch/i386/kernel/time.c
--- x-ref/arch/i386/kernel/time.c 2003-06-13 22:07:23.000000000 +0200
+++ x/arch/i386/kernel/time.c 2003-08-31 03:13:46.000000000 +0200
@@ -42,6 +42,7 @@
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/smp.h>
+#include <linux/frlock.h>
#include <asm/io.h>
#include <asm/smp.h>
@@ -79,7 +80,7 @@ static unsigned long last_tsc_low; /* ls
*/
unsigned long fast_gettimeoffset_quotient;
-extern rwlock_t xtime_lock;
+extern frlock_t xtime_lock;
extern unsigned long wall_jiffies;
spinlock_t rtc_lock = SPIN_LOCK_UNLOCKED;
@@ -158,6 +159,7 @@ extern spinlock_t i8259A_lock;
static unsigned long do_slow_gettimeoffset(void)
{
int count;
+ unsigned long flags;
static int count_p = LATCH; /* for the first call after boot */
static unsigned long jiffies_p = 0;
@@ -168,7 +170,7 @@ static unsigned long do_slow_gettimeoffs
unsigned long jiffies_t;
/* gets recalled with irq locally disabled */
- spin_lock(&i8253_lock);
+ spin_lock_irqsave(&i8253_lock, flags);
/* timer count may underflow right here */
outb_p(0x00, 0x43); /* latch the count ASAP */
@@ -190,7 +192,7 @@ static unsigned long do_slow_gettimeoffs
count = LATCH - 1;
}
- spin_unlock(&i8253_lock);
+ spin_unlock_irqrestore(&i8253_lock, flags);
/*
* avoiding timer inconsistencies (they are rare, but they happen)...
@@ -211,13 +213,13 @@ static unsigned long do_slow_gettimeoffs
int i;
- spin_lock(&i8259A_lock);
+ spin_lock_irqsave(&i8259A_lock, flags);
/*
* This is tricky when I/O APICs are used;
* see do_timer_interrupt().
*/
i = inb(0x20);
- spin_unlock(&i8259A_lock);
+ spin_unlock_irqrestore(&i8259A_lock, flags);
/* assumption about timer being IRQ0 */
if (i & 0x01) {
@@ -441,19 +443,21 @@ void __cyclone_delay(unsigned long loops
*/
void do_gettimeofday(struct timeval *tv)
{
- unsigned long flags;
+ unsigned long seq;
unsigned long usec, sec;
- read_lock_irqsave(&xtime_lock, flags);
- usec = do_gettimeoffset();
- {
- unsigned long lost = jiffies - wall_jiffies;
- if (lost)
- usec += lost * (1000000 / HZ);
- }
- sec = xtime.tv_sec;
- usec += xtime.tv_usec;
- read_unlock_irqrestore(&xtime_lock, flags);
+ do {
+ seq = fr_read_begin(&xtime_lock);
+ usec = do_gettimeoffset();
+ {
+ unsigned long lost = jiffies - wall_jiffies;
+ if (lost)
+ usec += lost * (1000000 / HZ);
+ }
+
+ sec = xtime.tv_sec;
+ usec += xtime.tv_usec;
+ } while (seq != fr_read_end(&xtime_lock));
while (usec >= 1000000) {
usec -= 1000000;
@@ -466,7 +470,7 @@ void do_gettimeofday(struct timeval *tv)
void do_settimeofday(struct timeval *tv)
{
- write_lock_irq(&xtime_lock);
+ fr_write_lock_irq(&xtime_lock);
/*
* This is revolting. We need to set "xtime" correctly. However, the
* value in this location is the value at the most recent update of
@@ -486,7 +490,7 @@ void do_settimeofday(struct timeval *tv)
time_status |= STA_UNSYNC;
time_maxerror = NTP_PHASE_LIMIT;
time_esterror = NTP_PHASE_LIMIT;
- write_unlock_irq(&xtime_lock);
+ fr_write_unlock_irq(&xtime_lock);
}
/*
@@ -652,7 +656,7 @@ static void timer_interrupt(int irq, voi
* the irq version of write_lock because as just said we have irq
* locally disabled. -arca
*/
- write_lock(&xtime_lock);
+ fr_write_lock(&xtime_lock);
if(use_cyclone)
mark_timeoffset_cyclone();
@@ -708,7 +712,7 @@ static void timer_interrupt(int irq, voi
do_timer_interrupt(irq, NULL, regs);
- write_unlock(&xtime_lock);
+ fr_write_unlock(&xtime_lock);
}
diff -urNp --exclude CVS --exclude BitKeeper x-ref/arch/ia64/kernel/time.c x/arch/ia64/kernel/time.c
--- x-ref/arch/ia64/kernel/time.c 2003-08-26 00:12:44.000000000 +0200
+++ x/arch/ia64/kernel/time.c 2003-08-31 03:13:46.000000000 +0200
@@ -16,6 +16,7 @@
#include <linux/time.h>
#include <linux/interrupt.h>
#include <linux/efi.h>
+#include <linux/frlock.h>
#include <asm/delay.h>
#include <asm/hw_irq.h>
@@ -23,7 +24,7 @@
#include <asm/sal.h>
#include <asm/system.h>
-extern rwlock_t xtime_lock;
+extern frlock_t xtime_lock;
extern unsigned long wall_jiffies;
extern unsigned long last_time_offset;
@@ -84,7 +85,7 @@ gettimeoffset (void)
void
do_settimeofday (struct timeval *tv)
{
- write_lock_irq(&xtime_lock);
+ fr_write_lock_irq(&xtime_lock);
{
/*
* This is revolting. We need to set "xtime" correctly. However, the value
@@ -106,16 +107,16 @@ do_settimeofday (struct timeval *tv)
time_maxerror = NTP_PHASE_LIMIT;
time_esterror = NTP_PHASE_LIMIT;
}
- write_unlock_irq(&xtime_lock);
+ fr_write_unlock_irq(&xtime_lock);
}
void
do_gettimeofday (struct timeval *tv)
{
- unsigned long flags, usec, sec, old;
+ unsigned long seq, usec, sec, old;
- read_lock_irqsave(&xtime_lock, flags);
- {
+ do {
+ seq = fr_read_begin(&xtime_lock);
usec = gettimeoffset();
/*
@@ -132,8 +133,7 @@ do_gettimeofday (struct timeval *tv)
sec = xtime.tv_sec;
usec += xtime.tv_usec;
- }
- read_unlock_irqrestore(&xtime_lock, flags);
+ } while (seq != fr_read_end(&xtime_lock));
while (usec >= 1000000) {
usec -= 1000000;
@@ -176,10 +176,10 @@ timer_interrupt(int irq, void *dev_id, s
* another CPU. We need to avoid to SMP race by acquiring the
* xtime_lock.
*/
- write_lock(&xtime_lock);
+ fr_write_lock(&xtime_lock);
do_timer(regs);
local_cpu_data->itm_next = new_itm;
- write_unlock(&xtime_lock);
+ fr_write_unlock(&xtime_lock);
} else
local_cpu_data->itm_next = new_itm;
diff -urNp --exclude CVS --exclude BitKeeper x-ref/arch/m68k/kernel/time.c x/arch/m68k/kernel/time.c
--- x-ref/arch/m68k/kernel/time.c 2003-06-13 22:07:23.000000000 +0200
+++ x/arch/m68k/kernel/time.c 2003-08-31 03:13:46.000000000 +0200
@@ -17,6 +17,7 @@
#include <linux/param.h>
#include <linux/string.h>
#include <linux/mm.h>
+#include <linux/frlock.h>
#include <asm/machdep.h>
#include <asm/io.h>
@@ -102,7 +103,7 @@ void time_init(void)
mach_sched_init(timer_interrupt);
}
-extern rwlock_t xtime_lock;
+extern frlock_t xtime_lock;
/*
* This version of gettimeofday has near microsecond resolution.
@@ -110,17 +111,18 @@ extern rwlock_t xtime_lock;
void do_gettimeofday(struct timeval *tv)
{
extern unsigned long wall_jiffies;
- unsigned long flags;
+ unsigned long seq;
unsigned long usec, sec, lost;
- read_lock_irqsave(&xtime_lock, flags);
- usec = mach_gettimeoffset();
- lost = jiffies - wall_jiffies;
- if (lost)
- usec += lost * (1000000/HZ);
- sec = xtime.tv_sec;
- usec += xtime.tv_usec;
- read_unlock_irqrestore(&xtime_lock, flags);
+ do {
+ seq = fr_read_begin(&xtime_lock);
+ usec = mach_gettimeoffset();
+ lost = jiffies - wall_jiffies;
+ if (lost)
+ usec += lost * (1000000/HZ);
+ sec = xtime.tv_sec;
+ usec += xtime.tv_usec;
+ } while (seq != fr_read_end(&xtime_lock));
while (usec >= 1000000) {
usec -= 1000000;
@@ -133,7 +135,7 @@ void do_gettimeofday(struct timeval *tv)
void do_settimeofday(struct timeval *tv)
{
- write_lock_irq(&xtime_lock);
+ fr_write_lock_irq(&xtime_lock);
/* This is revolting. We need to set the xtime.tv_usec
* correctly. However, the value in this location is
* is value at the last tick.
@@ -152,5 +154,5 @@ void do_settimeofday(struct timeval *tv)
time_status |= STA_UNSYNC;
time_maxerror = NTP_PHASE_LIMIT;
time_esterror = NTP_PHASE_LIMIT;
- write_unlock_irq(&xtime_lock);
+ fr_write_unlock_irq(&xtime_lock);
}
diff -urNp --exclude CVS --exclude BitKeeper x-ref/arch/parisc/kernel/time.c x/arch/parisc/kernel/time.c
--- x-ref/arch/parisc/kernel/time.c 2002-11-29 02:22:56.000000000 +0100
+++ x/arch/parisc/kernel/time.c 2003-08-31 03:13:46.000000000 +0200
@@ -21,6 +21,7 @@
#include <linux/time.h>
#include <linux/init.h>
#include <linux/smp.h>
+#include <linux/frlock.h>
#include <asm/uaccess.h>
#include <asm/io.h>
@@ -33,7 +34,7 @@
/* xtime and wall_jiffies keep wall-clock time */
extern unsigned long wall_jiffies;
-extern rwlock_t xtime_lock;
+extern frlock_t xtime_lock;
static long clocktick; /* timer cycles per tick */
static long halftick;
@@ -95,7 +96,7 @@ void timer_interrupt(int irq, void *dev_
#endif
if (cpu == 0) {
extern int pc_in_user_space;
- write_lock(&xtime_lock);
+ fr_write_lock(&xtime_lock);
#ifndef CONFIG_SMP
if (!user_mode(regs))
parisc_do_profile(regs->iaoq[0]);
@@ -103,7 +104,7 @@ void timer_interrupt(int irq, void *dev_
parisc_do_profile(&pc_in_user_space);
#endif
do_timer(regs);
- write_unlock(&xtime_lock);
+ fr_write_unlock(&xtime_lock);
}
}
@@ -158,16 +159,15 @@ gettimeoffset (void)
void
do_gettimeofday (struct timeval *tv)
{
- unsigned long flags, usec, sec;
+ unsigned long seq, usec, sec;
- read_lock_irqsave(&xtime_lock, flags);
- {
+ do {
+ seq = fr_read_begin(&xtime_lock);
usec = gettimeoffset();
sec = xtime.tv_sec;
usec += xtime.tv_usec;
- }
- read_unlock_irqrestore(&xtime_lock, flags);
+ } while (seq != fr_read_end(&xtime_lock));
while (usec >= 1000000) {
usec -= 1000000;
@@ -181,7 +181,7 @@ do_gettimeofday (struct timeval *tv)
void
do_settimeofday (struct timeval *tv)
{
- write_lock_irq(&xtime_lock);
+ fr_write_lock_irq(&xtime_lock);
{
/*
* This is revolting. We need to set "xtime"
@@ -204,7 +204,7 @@ do_settimeofday (struct timeval *tv)
time_maxerror = NTP_PHASE_LIMIT;
time_esterror = NTP_PHASE_LIMIT;
}
- write_unlock_irq(&xtime_lock);
+ fr_write_unlock_irq(&xtime_lock);
}
@@ -226,10 +226,10 @@ void __init time_init(void)
mtctl(next_tick, 16);
if(pdc_tod_read(&tod_data) == 0) {
- write_lock_irq(&xtime_lock);
+ fr_write_lock_irq(&xtime_lock);
xtime.tv_sec = tod_data.tod_sec;
xtime.tv_usec = tod_data.tod_usec;
- write_unlock_irq(&xtime_lock);
+ fr_write_unlock_irq(&xtime_lock);
} else {
printk(KERN_ERR "Error reading tod clock\n");
xtime.tv_sec = 0;
diff -urNp --exclude CVS --exclude BitKeeper x-ref/arch/ppc/kernel/time.c x/arch/ppc/kernel/time.c
--- x-ref/arch/ppc/kernel/time.c 2003-08-26 00:12:47.000000000 +0200
+++ x/arch/ppc/kernel/time.c 2003-08-31 03:13:46.000000000 +0200
@@ -56,6 +56,7 @@
#include <linux/mc146818rtc.h>
#include <linux/time.h>
#include <linux/init.h>
+#include <linux/frlock.h>
#include <asm/segment.h>
#include <asm/io.h>
@@ -73,7 +74,7 @@ extern int do_sys_settimeofday(struct ti
/* keep track of when we need to update the rtc */
time_t last_rtc_update;
-extern rwlock_t xtime_lock;
+extern frlock_t xtime_lock;
/* The decrementer counts down by 128 every 128ns on a 601. */
#define DECREMENTER_COUNT_601 (1000000000 / HZ)
@@ -163,7 +164,7 @@ int timer_interrupt(struct pt_regs * reg
continue;
/* We are in an interrupt, no need to save/restore flags */
- write_lock(&xtime_lock);
+ fr_write_lock(&xtime_lock);
tb_last_stamp = jiffy_stamp;
do_timer(regs);
@@ -193,7 +194,7 @@ int timer_interrupt(struct pt_regs * reg
/* Try again one minute later */
last_rtc_update += 60;
}
- write_unlock(&xtime_lock);
+ fr_write_unlock(&xtime_lock);
}
if (!disarm_decr[cpu])
set_dec(next_dec);
@@ -216,22 +217,23 @@ int timer_interrupt(struct pt_regs * reg
*/
void do_gettimeofday(struct timeval *tv)
{
- unsigned long flags;
+ unsigned long seq;
unsigned delta, lost_ticks, usec, sec;
- read_lock_irqsave(&xtime_lock, flags);
- sec = xtime.tv_sec;
- usec = xtime.tv_usec;
- delta = tb_ticks_since(tb_last_stamp);
+ do {
+ seq = fr_read_begin(&xtime_lock);
+ sec = xtime.tv_sec;
+ usec = xtime.tv_usec;
+ delta = tb_ticks_since(tb_last_stamp);
#ifdef CONFIG_SMP
- /* As long as timebases are not in sync, gettimeofday can only
- * have jiffy resolution on SMP.
- */
- if (!smp_tb_synchronized)
- delta = 0;
+ /* As long as timebases are not in sync, gettimeofday can only
+ * have jiffy resolution on SMP.
+ */
+ if (!smp_tb_synchronized)
+ delta = 0;
#endif /* CONFIG_SMP */
- lost_ticks = jiffies - wall_jiffies;
- read_unlock_irqrestore(&xtime_lock, flags);
+ lost_ticks = jiffies - wall_jiffies;
+ } while (seq != fr_read_end(&xtime_lock));
usec += mulhwu(tb_to_us, tb_ticks_per_jiffy * lost_ticks + delta);
while (usec >= 1000000) {
@@ -247,7 +249,7 @@ void do_settimeofday(struct timeval *tv)
unsigned long flags;
int tb_delta, new_usec, new_sec;
- write_lock_irqsave(&xtime_lock, flags);
+ fr_write_lock_irqsave(&xtime_lock, flags);
/* Updating the RTC is not the job of this code. If the time is
* stepped under NTP, the RTC will be update after STA_UNSYNC
* is cleared. Tool like clock/hwclock either copy the RTC
@@ -287,7 +289,7 @@ void do_settimeofday(struct timeval *tv)
time_state = TIME_ERROR; /* p. 24, (a) */
time_maxerror = NTP_PHASE_LIMIT;
time_esterror = NTP_PHASE_LIMIT;
- write_unlock_irqrestore(&xtime_lock, flags);
+ fr_write_unlock_irqrestore(&xtime_lock, flags);
}
/* This function is only called on the boot processor */
diff -urNp --exclude CVS --exclude BitKeeper x-ref/arch/ppc64/kernel/time.c x/arch/ppc64/kernel/time.c
--- x-ref/arch/ppc64/kernel/time.c 2003-08-26 00:12:47.000000000 +0200
+++ x/arch/ppc64/kernel/time.c 2003-08-31 03:13:46.000000000 +0200
@@ -46,6 +46,7 @@
#include <linux/mc146818rtc.h>
#include <linux/time.h>
#include <linux/init.h>
+#include <linux/frlock.h>
#include <asm/naca.h>
#include <asm/segment.h>
@@ -69,7 +70,7 @@ extern void setup_before_console_init();
/* keep track of when we need to update the rtc */
time_t last_rtc_update;
-extern rwlock_t xtime_lock;
+extern frlock_t xtime_lock;
extern int piranha_simulator;
#ifdef CONFIG_PPC_ISERIES
unsigned long iSeries_recal_titan = 0;
@@ -268,12 +269,12 @@ int timer_interrupt(struct pt_regs * reg
smp_local_timer_interrupt(regs);
#endif
if (cpu == 0) {
- write_lock(&xtime_lock);
+ fr_write_lock(&xtime_lock);
tb_last_stamp = lpaca->next_jiffy_update_tb;
do_timer(regs);
timer_sync_xtime( cur_tb );
timer_check_rtc();
- write_unlock(&xtime_lock);
+ fr_write_unlock(&xtime_lock);
if ( adjusting_time && (time_adjust == 0) )
ppc_adjtimex();
}
@@ -378,7 +379,7 @@ void do_settimeofday(struct timeval *tv)
long int tb_delta, new_usec, new_sec;
unsigned long new_xsec;
- write_lock_irqsave(&xtime_lock, flags);
+ fr_write_lock_irqsave(&xtime_lock, flags);
/* Updating the RTC is not the job of this code. If the time is
* stepped under NTP, the RTC will be update after STA_UNSYNC
* is cleared. Tool like clock/hwclock either copy the RTC
@@ -432,7 +433,7 @@ void do_settimeofday(struct timeval *tv)
systemcfg->tz_minuteswest = sys_tz.tz_minuteswest;
systemcfg->tz_dsttime = sys_tz.tz_dsttime;
- write_unlock_irqrestore(&xtime_lock, flags);
+ fr_write_unlock_irqrestore(&xtime_lock, flags);
}
/*
@@ -496,7 +497,7 @@ void __init time_init(void)
if ( ! piranha_simulator ) {
ppc_md.get_boot_time(&tm);
}
- write_lock_irqsave(&xtime_lock, flags);
+ fr_write_lock_irqsave(&xtime_lock, flags);
xtime.tv_sec = mktime(tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday,
tm.tm_hour, tm.tm_min, tm.tm_sec);
tb_last_stamp = get_tb();
@@ -513,7 +514,7 @@ void __init time_init(void)
xtime.tv_usec = 0;
last_rtc_update = xtime.tv_sec;
- write_unlock_irqrestore(&xtime_lock, flags);
+ fr_write_unlock_irqrestore(&xtime_lock, flags);
/* Not exact, but the timer interrupt takes care of this */
set_dec(tb_ticks_per_jiffy);
@@ -621,7 +622,7 @@ void ppc_adjtimex(void)
new_tb_to_xs = divres.result_low;
new_xsec = mulhdu( tb_ticks, new_tb_to_xs );
- write_lock_irqsave( &xtime_lock, flags );
+ fr_write_lock_irqsave( &xtime_lock, flags );
old_xsec = mulhdu( tb_ticks, systemcfg->tb_to_xs );
new_stamp_xsec = systemcfg->stamp_xsec + old_xsec - new_xsec;
@@ -641,7 +642,7 @@ void ppc_adjtimex(void)
wmb();
++(systemcfg->tb_update_count);
- write_unlock_irqrestore( &xtime_lock, flags );
+ fr_write_unlock_irqrestore( &xtime_lock, flags );
}
diff -urNp --exclude CVS --exclude BitKeeper x-ref/arch/s390/kernel/time.c x/arch/s390/kernel/time.c
--- x-ref/arch/s390/kernel/time.c 2003-06-13 22:07:24.000000000 +0200
+++ x/arch/s390/kernel/time.c 2003-08-31 03:13:46.000000000 +0200
@@ -23,6 +23,7 @@
#include <linux/init.h>
#include <linux/smp.h>
#include <linux/types.h>
+#include <linux/frlock.h>
#include <asm/uaccess.h>
#include <asm/delay.h>
@@ -42,7 +43,7 @@
static ext_int_info_t ext_int_info_timer;
static uint64_t init_timer_cc;
-extern rwlock_t xtime_lock;
+extern frlock_t xtime_lock;
extern unsigned long wall_jiffies;
void tod_to_timeval(__u64 todval, struct timeval *xtime)
@@ -95,13 +96,14 @@ static inline unsigned long do_gettimeof
*/
void do_gettimeofday(struct timeval *tv)
{
- unsigned long flags;
+ unsigned long seq;
unsigned long usec, sec;
- read_lock_irqsave(&xtime_lock, flags);
- sec = xtime.tv_sec;
- usec = xtime.tv_usec + do_gettimeoffset();
- read_unlock_irqrestore(&xtime_lock, flags);
+ do {
+ seq = fr_read_begin(&xtime_lock);
+ sec = xtime.tv_sec;
+ usec = xtime.tv_usec + do_gettimeoffset();
+ } while (seq != fr_read_end(&xtime_lock));
while (usec >= 1000000) {
usec -= 1000000;
@@ -115,7 +117,7 @@ void do_gettimeofday(struct timeval *tv)
void do_settimeofday(struct timeval *tv)
{
- write_lock_irq(&xtime_lock);
+ fr_write_lock_irq(&xtime_lock);
/* This is revolting. We need to set the xtime.tv_usec
* correctly. However, the value in this location is
* is value at the last tick.
@@ -134,7 +136,7 @@ void do_settimeofday(struct timeval *tv)
time_status |= STA_UNSYNC;
time_maxerror = NTP_PHASE_LIMIT;
time_esterror = NTP_PHASE_LIMIT;
- write_unlock_irq(&xtime_lock);
+ fr_write_unlock_irq(&xtime_lock);
}
/*
@@ -160,13 +162,13 @@ static void do_comparator_interrupt(stru
#ifdef CONFIG_SMP
if (S390_lowcore.cpu_data.cpu_addr == boot_cpu_addr)
- write_lock(&xtime_lock);
+ fr_write_lock(&xtime_lock);
update_process_times(user_mode(regs));
if (S390_lowcore.cpu_data.cpu_addr == boot_cpu_addr) {
do_timer(regs);
- write_unlock(&xtime_lock);
+ fr_write_unlock(&xtime_lock);
}
#else
do_timer(regs);
diff -urNp --exclude CVS --exclude BitKeeper x-ref/arch/s390x/kernel/time.c x/arch/s390x/kernel/time.c
--- x-ref/arch/s390x/kernel/time.c 2003-06-13 22:07:24.000000000 +0200
+++ x/arch/s390x/kernel/time.c 2003-08-31 03:13:46.000000000 +0200
@@ -23,6 +23,7 @@
#include <linux/init.h>
#include <linux/smp.h>
#include <linux/types.h>
+#include <linux/frlock.h>
#include <asm/uaccess.h>
#include <asm/delay.h>
@@ -42,7 +43,7 @@
static ext_int_info_t ext_int_info_timer;
static uint64_t init_timer_cc;
-extern rwlock_t xtime_lock;
+extern frlock_t xtime_lock;
extern unsigned long wall_jiffies;
void tod_to_timeval(__u64 todval, struct timeval *xtime)
@@ -68,13 +69,14 @@ static inline unsigned long do_gettimeof
*/
void do_gettimeofday(struct timeval *tv)
{
- unsigned long flags;
+ unsigned long seq;
unsigned long usec, sec;
- read_lock_irqsave(&xtime_lock, flags);
- sec = xtime.tv_sec;
- usec = xtime.tv_usec + do_gettimeoffset();
- read_unlock_irqrestore(&xtime_lock, flags);
+ do {
+ seq = fr_read_begin(&xtime_lock);
+ sec = xtime.tv_sec;
+ usec = xtime.tv_usec + do_gettimeoffset();
+ } while (seq != fr_read_end(&xtime_lock));
while (usec >= 1000000) {
usec -= 1000000;
@@ -88,7 +90,7 @@ void do_gettimeofday(struct timeval *tv)
void do_settimeofday(struct timeval *tv)
{
- write_lock_irq(&xtime_lock);
+ fr_write_lock_irq(&xtime_lock);
/* This is revolting. We need to set the xtime.tv_usec
* correctly. However, the value in this location is
* is value at the last tick.
@@ -107,7 +109,7 @@ void do_settimeofday(struct timeval *tv)
time_status |= STA_UNSYNC;
time_maxerror = NTP_PHASE_LIMIT;
time_esterror = NTP_PHASE_LIMIT;
- write_unlock_irq(&xtime_lock);
+ fr_write_unlock_irq(&xtime_lock);
}
/*
@@ -133,13 +135,13 @@ static void do_comparator_interrupt(stru
#ifdef CONFIG_SMP
if (S390_lowcore.cpu_data.cpu_addr == boot_cpu_addr)
- write_lock(&xtime_lock);
+ fr_write_lock(&xtime_lock);
update_process_times(user_mode(regs));
if (S390_lowcore.cpu_data.cpu_addr == boot_cpu_addr) {
do_timer(regs);
- write_unlock(&xtime_lock);
+ fr_write_unlock(&xtime_lock);
}
#else
do_timer(regs);
diff -urNp --exclude CVS --exclude BitKeeper x-ref/arch/sh/kernel/time.c x/arch/sh/kernel/time.c
--- x-ref/arch/sh/kernel/time.c 2003-08-26 00:12:51.000000000 +0200
+++ x/arch/sh/kernel/time.c 2003-08-31 03:13:46.000000000 +0200
@@ -22,6 +22,7 @@
#include <linux/delay.h>
#include <linux/init.h>
#include <linux/smp.h>
+#include <linux/frlock.h>
#include <asm/processor.h>
#include <asm/uaccess.h>
@@ -99,7 +100,7 @@
#endif /* CONFIG_CPU_SUBTYPE_ST40 */
#endif /* __sh3__ or __SH4__ */
-extern rwlock_t xtime_lock;
+extern frlock_t xtime_lock;
extern unsigned long wall_jiffies;
#define TICK_SIZE tick
@@ -154,19 +155,18 @@ static unsigned long do_gettimeoffset(vo
void do_gettimeofday(struct timeval *tv)
{
- unsigned long flags;
+ unsigned long seq, lost;
unsigned long usec, sec;
- read_lock_irqsave(&xtime_lock, flags);
- usec = do_gettimeoffset();
- {
- unsigned long lost = jiffies - wall_jiffies;
+ do {
+ seq = fr_read_begin(&xtime_lock);
+ usec = do_gettimeoffset();
+ lost = jiffies - wall_jiffies;
if (lost)
usec += lost * (1000000 / HZ);
- }
- sec = xtime.tv_sec;
- usec += xtime.tv_usec;
- read_unlock_irqrestore(&xtime_lock, flags);
+ sec = xtime.tv_sec;
+ usec += xtime.tv_usec;
+ } while (seq != fr_read_end(&xtime_lock));
while (usec >= 1000000) {
usec -= 1000000;
@@ -179,7 +179,7 @@ void do_gettimeofday(struct timeval *tv)
void do_settimeofday(struct timeval *tv)
{
- write_lock_irq(&xtime_lock);
+ fr_write_lock_irq(&xtime_lock);
/*
* This is revolting. We need to set "xtime" correctly. However, the
* value in this location is the value at the most recent update of
@@ -199,7 +199,7 @@ void do_settimeofday(struct timeval *tv)
time_status |= STA_UNSYNC;
time_maxerror = NTP_PHASE_LIMIT;
time_esterror = NTP_PHASE_LIMIT;
- write_unlock_irq(&xtime_lock);
+ fr_write_unlock_irq(&xtime_lock);
}
/* last time the RTC clock got updated */
@@ -279,9 +279,9 @@ static void timer_interrupt(int irq, voi
* the irq version of write_lock because as just said we have irq
* locally disabled. -arca
*/
- write_lock(&xtime_lock);
+ fr_write_lock(&xtime_lock);
do_timer_interrupt(irq, NULL, regs);
- write_unlock(&xtime_lock);
+ fr_write_unlock(&xtime_lock);
}
static unsigned int __init get_timer_frequency(void)
diff -urNp --exclude CVS --exclude BitKeeper x-ref/arch/sparc/kernel/time.c x/arch/sparc/kernel/time.c
--- x-ref/arch/sparc/kernel/time.c 2003-06-13 22:07:24.000000000 +0200
+++ x/arch/sparc/kernel/time.c 2003-08-31 03:13:46.000000000 +0200
@@ -27,6 +27,7 @@
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/ioport.h>
+#include <linux/frlock.h>
#include <asm/oplib.h>
#include <asm/segment.h>
@@ -41,7 +42,7 @@
#include <asm/page.h>
#include <asm/pcic.h>
-extern rwlock_t xtime_lock;
+extern frlock_t xtime_lock;
enum sparc_clock_type sp_clock_typ;
spinlock_t mostek_lock = SPIN_LOCK_UNLOCKED;
@@ -133,7 +134,7 @@ void timer_interrupt(int irq, void *dev_
#endif
clear_clock_irq();
- write_lock(&xtime_lock);
+ fr_write_lock(&xtime_lock);
do_timer(regs);
@@ -147,7 +148,7 @@ void timer_interrupt(int irq, void *dev_
else
last_rtc_update = xtime.tv_sec - 600; /* do it again in 60 s */
}
- write_unlock(&xtime_lock);
+ fr_write_unlock(&xtime_lock);
}
/* Kick start a stopped clock (procedure from the Sun NVRAM/hostid FAQ). */
@@ -511,9 +512,9 @@ void do_gettimeofday(struct timeval *tv)
void do_settimeofday(struct timeval *tv)
{
- write_lock_irq(&xtime_lock);
+ fr_write_lock_irq(&xtime_lock);
bus_do_settimeofday(tv);
- write_unlock_irq(&xtime_lock);
+ fr_write_unlock_irq(&xtime_lock);
}
static void sbus_do_settimeofday(struct timeval *tv)
diff -urNp --exclude CVS --exclude BitKeeper x-ref/arch/sparc64/kernel/time.c x/arch/sparc64/kernel/time.c
--- x-ref/arch/sparc64/kernel/time.c 2003-06-13 22:07:24.000000000 +0200
+++ x/arch/sparc64/kernel/time.c 2003-08-31 03:13:46.000000000 +0200
@@ -23,6 +23,7 @@
#include <linux/mc146818rtc.h>
#include <linux/delay.h>
#include <linux/timer.h>
+#include <linux/frlock.h>
#include <asm/oplib.h>
#include <asm/mostek.h>
@@ -37,7 +38,7 @@
#include <asm/starfire.h>
#include <asm/smp.h>
-extern rwlock_t xtime_lock;
+extern frlock_t xtime_lock;
extern unsigned long wall_jiffies;
spinlock_t mostek_lock = SPIN_LOCK_UNLOCKED;
@@ -461,7 +462,7 @@ static void timer_interrupt(int irq, voi
{
unsigned long ticks, pstate;
- write_lock(&xtime_lock);
+ fr_write_lock(&xtime_lock);
do {
#ifndef CONFIG_SMP
@@ -489,13 +490,13 @@ static void timer_interrupt(int irq, voi
timer_check_rtc();
- write_unlock(&xtime_lock);
+ fr_write_unlock(&xtime_lock);
}
#ifdef CONFIG_SMP
void timer_tick_interrupt(struct pt_regs *regs)
{
- write_lock(&xtime_lock);
+ fr_write_lock(&xtime_lock);
do_timer(regs);
@@ -506,7 +507,7 @@ void timer_tick_interrupt(struct pt_regs
timer_check_rtc();
- write_unlock(&xtime_lock);
+ fr_write_unlock(&xtime_lock);
}
#endif
@@ -1004,7 +1005,7 @@ void do_settimeofday(struct timeval *tv)
if (this_is_starfire)
return;
- write_lock_irq(&xtime_lock);
+ fr_write_lock_irq(&xtime_lock);
tv->tv_usec -= do_gettimeoffset();
tv->tv_usec -= (jiffies - wall_jiffies) * (1000000 / HZ);
@@ -1020,7 +1021,7 @@ void do_settimeofday(struct timeval *tv)
time_maxerror = NTP_PHASE_LIMIT;
time_esterror = NTP_PHASE_LIMIT;
- write_unlock_irq(&xtime_lock);
+ fr_write_unlock_irq(&xtime_lock);
}
void do_gettimeofday(struct timeval *tv)
diff -urNp --exclude CVS --exclude BitKeeper x-ref/arch/x86_64/kernel/time.c x/arch/x86_64/kernel/time.c
--- x-ref/arch/x86_64/kernel/time.c 2003-08-26 00:12:51.000000000 +0200
+++ x/arch/x86_64/kernel/time.c 2003-08-31 03:13:46.000000000 +0200
@@ -19,10 +19,11 @@
#include <linux/mc146818rtc.h>
#include <linux/irq.h>
#include <linux/ioport.h>
+#include <linux/frlock.h>
#include <asm/vsyscall.h>
#include <asm/timex.h>
-extern rwlock_t xtime_lock;
+extern frlock_t xtime_lock;
spinlock_t rtc_lock = SPIN_LOCK_UNLOCKED;
spinlock_t i8253_lock = SPIN_LOCK_UNLOCKED;
@@ -105,7 +106,7 @@ void do_gettimeofday(struct timeval *tv)
void do_settimeofday(struct timeval *tv)
{
- write_lock_irq(&xtime_lock);
+ fr_write_lock_irq(&xtime_lock);
vxtime_lock();
tv->tv_usec -= (jiffies - wall_jiffies) * tick
@@ -124,7 +125,7 @@ void do_settimeofday(struct timeval *tv)
time_maxerror = NTP_PHASE_LIMIT;
time_esterror = NTP_PHASE_LIMIT;
- write_unlock_irq(&xtime_lock);
+ fr_write_unlock_irq(&xtime_lock);
}
/*
@@ -207,7 +208,7 @@ static void timer_interrupt(int irq, voi
* variables, because both do_timer() and us change them -arca+vojtech
*/
- write_lock(&xtime_lock);
+ fr_write_lock(&xtime_lock);
vxtime_lock();
{
@@ -283,7 +284,7 @@ static void timer_interrupt(int irq, voi
}
vxtime_unlock();
- write_unlock(&xtime_lock);
+ fr_write_unlock(&xtime_lock);
}
static unsigned long get_cmos_time(void)
@@ -506,10 +507,10 @@ void __init time_init(void)
hpet_address = 0;
#endif
- write_lock(&xtime_lock);
+ fr_write_lock(&xtime_lock);
xtime.tv_sec = get_cmos_time();
xtime.tv_usec = 0;
- write_unlock(&xtime_lock);
+ fr_write_unlock(&xtime_lock);
if (!hpet_init()) {
vxtime_hz = (1000000000000000L + hpet_period / 2) / hpet_period;
diff -urNp --exclude CVS --exclude BitKeeper x-ref/include/linux/frlock.h x/include/linux/frlock.h
--- x-ref/include/linux/frlock.h 1970-01-01 01:00:00.000000000 +0100
+++ x/include/linux/frlock.h 2003-08-31 03:13:46.000000000 +0200
@@ -0,0 +1,101 @@
+#ifndef __LINUX_FRLOCK_H
+#define __LINUX_FRLOCK_H
+
+/*
+ * Fast read-write spinlocks.
+ *
+ * Fast reader/writer locks without starving writers. This type of
+ * lock for data where the reader wants a consitent set of information
+ * and is willing to retry if the information changes. Readers never
+ * block but they may have to retry if a writer is in
+ * progress. Writers do not wait for readers.
+ *
+ * Generalization on sequence variables used for gettimeofday on x86-64
+ * by Andrea Arcangeli
+ *
+ * This is not as cache friendly as brlock. Also, this will not work
+ * for data that contains pointers, because any writer could
+ * invalidate a pointer that a reader was following.
+ *
+ *
+ * Expected reader usage:
+ * do {
+ * seq = fr_read_begin();
+ * ...
+ * } while (seq != fr_read_end());
+ *
+ * On non-SMP the spin locks disappear but the writer still needs
+ * to increment the sequence variables because an interrupt routine could
+ * change the state of the data.
+ */
+
+#include <linux/config.h>
+#include <linux/spinlock.h>
+#include <asm/system.h>
+
+typedef struct {
+ spinlock_t lock;
+ unsigned pre_sequence;
+ unsigned post_sequence;
+} frlock_t;
+
+#define FR_LOCK_UNLOCKED { SPIN_LOCK_UNLOCKED, 0, 0 }
+#define frlock_init(x) do { *(x) = (frlock_t) FR_LOCK_UNLOCKED; } while (0)
+
+static inline void fr_write_lock(frlock_t *rw)
+{
+ spin_lock(&rw->lock);
+ rw->pre_sequence++;
+ wmb();
+}
+
+static inline void fr_write_unlock(frlock_t *rw)
+{
+ wmb();
+ rw->post_sequence++;
+ spin_unlock(&rw->lock);
+}
+
+static inline int fr_write_trylock(frlock_t *rw)
+{
+ int ret = spin_trylock(&rw->lock);
+
+ if (ret) {
+ ++rw->pre_sequence;
+ wmb();
+ }
+ return ret;
+}
+
+static inline unsigned fr_read_begin(frlock_t *rw)
+{
+ unsigned ret = rw->post_sequence;
+ rmb();
+ return ret;
+
+}
+
+static inline unsigned fr_read_end(frlock_t *rw)
+{
+ rmb();
+ return rw->pre_sequence;
+}
+
+/*
+ * Possible sw/hw IRQ protected versions of the interfaces.
+ */
+#define fr_write_lock_irqsave(lock, flags) \
+ do { local_irq_save(flags); fr_write_lock(lock); } while (0)
+#define fr_write_lock_irq(lock) \
+ do { local_irq_disable(); fr_write_lock(lock); } while (0)
+#define fr_write_lock_bh(lock) \
+ do { local_bh_disable(); fr_write_lock(lock); } while (0)
+
+#define fr_write_unlock_irqrestore(lock, flags) \
+ do { fr_write_unlock(lock); local_irq_restore(flags); } while(0)
+#define fr_write_unlock_irq(lock) \
+ do { fr_write_unlock(lock); local_irq_enable(); } while(0)
+#define fr_write_unlock_bh(lock) \
+ do { fr_write_unlock(lock); local_bh_enable(); } while(0)
+
+#endif /* __LINUX_FRLOCK_H */
diff -urNp --exclude CVS --exclude BitKeeper x-ref/kernel/time.c x/kernel/time.c
--- x-ref/kernel/time.c 2002-11-29 02:23:18.000000000 +0100
+++ x/kernel/time.c 2003-08-31 03:13:46.000000000 +0200
@@ -27,6 +27,7 @@
#include <linux/mm.h>
#include <linux/timex.h>
#include <linux/smp_lock.h>
+#include <linux/frlock.h>
#include <asm/uaccess.h>
@@ -38,7 +39,7 @@ struct timezone sys_tz;
/* The xtime_lock is not only serializing the xtime read/writes but it's also
serializing all accesses to the global NTP variables now. */
-extern rwlock_t xtime_lock;
+extern frlock_t xtime_lock;
#if !defined(__alpha__) && !defined(__ia64__)
@@ -79,7 +80,7 @@ asmlinkage long sys_stime(int * tptr)
return -EPERM;
if (get_user(value, tptr))
return -EFAULT;
- write_lock_irq(&xtime_lock);
+ fr_write_lock_irq(&xtime_lock);
vxtime_lock();
xtime.tv_sec = value;
xtime.tv_usec = 0;
@@ -88,7 +89,7 @@ asmlinkage long sys_stime(int * tptr)
time_status |= STA_UNSYNC;
time_maxerror = NTP_PHASE_LIMIT;
time_esterror = NTP_PHASE_LIMIT;
- write_unlock_irq(&xtime_lock);
+ fr_write_unlock_irq(&xtime_lock);
return 0;
}
@@ -127,11 +128,11 @@ asmlinkage long sys_gettimeofday(struct
*/
inline static void warp_clock(void)
{
- write_lock_irq(&xtime_lock);
+ fr_write_lock_irq(&xtime_lock);
vxtime_lock();
xtime.tv_sec += sys_tz.tz_minuteswest * 60;
vxtime_unlock();
- write_unlock_irq(&xtime_lock);
+ fr_write_unlock_irq(&xtime_lock);
}
/*
@@ -235,7 +236,7 @@ int do_adjtimex(struct timex *txc)
if (txc->tick < 900000/HZ || txc->tick > 1100000/HZ)
return -EINVAL;
- write_lock_irq(&xtime_lock);
+ fr_write_lock_irq(&xtime_lock);
result = time_state; /* mostly `TIME_OK' */
/* Save for later - semantics of adjtime is to return old value */
@@ -390,7 +391,7 @@ leave: if ((time_status & (STA_UNSYNC|ST
txc->calcnt = pps_calcnt;
txc->errcnt = pps_errcnt;
txc->stbcnt = pps_stbcnt;
- write_unlock_irq(&xtime_lock);
+ fr_write_unlock_irq(&xtime_lock);
do_gettimeofday(&txc->time);
return(result);
}
diff -urNp --exclude CVS --exclude BitKeeper x-ref/kernel/timer.c x/kernel/timer.c
--- x-ref/kernel/timer.c 2003-08-31 03:13:37.000000000 +0200
+++ x/kernel/timer.c 2003-08-31 03:13:46.000000000 +0200
@@ -27,6 +27,7 @@
#include <linux/smp_lock.h>
#include <linux/interrupt.h>
#include <linux/kernel_stat.h>
+#include <linux/frlock.h>
#include <asm/uaccess.h>
@@ -86,7 +87,7 @@ unsigned long wall_jiffies;
/*
* This spinlock protect us from races in SMP while playing with xtime. -arca
*/
-rwlock_t xtime_lock = RW_LOCK_UNLOCKED;
+frlock_t xtime_lock = FR_LOCK_UNLOCKED;
/*
* This is the 'global' timer BH. This gets called only if one of