* 2 of the License, or (at your option) any later version.
*/
-#include <linux/config.h>
#include <linux/errno.h>
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/percpu.h>
#include <linux/rtc.h>
#include <linux/jiffies.h>
+#include <linux/posix-timers.h>
+#include <linux/irq.h>
#include <asm/io.h>
#include <asm/processor.h>
/* keep track of when we need to update the rtc */
time_t last_rtc_update;
-extern int piranha_simulator;
#ifdef CONFIG_PPC_ISERIES
unsigned long iSeries_recal_titan = 0;
unsigned long iSeries_recal_tb = 0;
unsigned long tb_ticks_per_usec = 100; /* sane default */
EXPORT_SYMBOL(tb_ticks_per_usec);
unsigned long tb_ticks_per_sec;
+EXPORT_SYMBOL(tb_ticks_per_sec); /* for cputime_t conversions */
u64 tb_to_xs;
unsigned tb_to_us;
-#define TICKLEN_SCALE (SHIFT_SCALE - 10)
+#define TICKLEN_SCALE TICK_LENGTH_SHIFT
u64 last_tick_len; /* units are ns / 2^TICKLEN_SCALE */
u64 ticklen_to_xs; /* 0.64 fraction */
struct gettimeofday_struct do_gtod;
-extern unsigned long wall_jiffies;
-
extern struct timezone sys_tz;
static long timezone_offset;
unsigned long ppc_proc_freq;
unsigned long ppc_tb_freq;
-u64 tb_last_jiffy __cacheline_aligned_in_smp;
-unsigned long tb_last_stamp;
+static u64 tb_last_jiffy __cacheline_aligned_in_smp;
+static DEFINE_PER_CPU(u64, last_jiffy);
+
+#ifdef CONFIG_VIRT_CPU_ACCOUNTING
+/*
+ * Factors for converting from cputime_t (timebase ticks) to
+ * jiffies, milliseconds, seconds, and clock_t (1/USER_HZ seconds).
+ * These are all stored as 0.64 fixed-point binary fractions.
+ */
+u64 __cputime_jiffies_factor;
+EXPORT_SYMBOL(__cputime_jiffies_factor);
+u64 __cputime_msec_factor;
+EXPORT_SYMBOL(__cputime_msec_factor);
+u64 __cputime_sec_factor;
+EXPORT_SYMBOL(__cputime_sec_factor);
+u64 __cputime_clockt_factor;
+EXPORT_SYMBOL(__cputime_clockt_factor);
+
+static void calc_cputime_factors(void)
+{
+ struct div_result res;
+
+ div128_by_32(HZ, 0, tb_ticks_per_sec, &res);
+ __cputime_jiffies_factor = res.result_low;
+ div128_by_32(1000, 0, tb_ticks_per_sec, &res);
+ __cputime_msec_factor = res.result_low;
+ div128_by_32(1, 0, tb_ticks_per_sec, &res);
+ __cputime_sec_factor = res.result_low;
+ div128_by_32(USER_HZ, 0, tb_ticks_per_sec, &res);
+ __cputime_clockt_factor = res.result_low;
+}
+
+/*
+ * Read the PURR on systems that have it, otherwise the timebase.
+ */
+static u64 read_purr(void)
+{
+ if (cpu_has_feature(CPU_FTR_PURR))
+ return mfspr(SPRN_PURR);
+ return mftb();
+}
+
+/*
+ * Account time for a transition between system, hard irq
+ * or soft irq state.
+ */
+void account_system_vtime(struct task_struct *tsk)
+{
+ u64 now, delta;
+ unsigned long flags;
+
+ local_irq_save(flags);
+ now = read_purr();
+ delta = now - get_paca()->startpurr;
+ get_paca()->startpurr = now;
+ if (!in_interrupt()) {
+ delta += get_paca()->system_time;
+ get_paca()->system_time = 0;
+ }
+ account_system_time(tsk, 0, delta);
+ local_irq_restore(flags);
+}
/*
- * Note that on ppc32 this only stores the bottom 32 bits of
- * the timebase value, but that's enough to tell when a jiffy
- * has passed.
+ * Transfer the user and system times accumulated in the paca
+ * by the exception entry and exit code to the generic process
+ * user and system time records.
+ * Must be called with interrupts disabled.
*/
-DEFINE_PER_CPU(unsigned long, last_jiffy);
+void account_process_vtime(struct task_struct *tsk)
+{
+ cputime_t utime;
+
+ utime = get_paca()->user_time;
+ get_paca()->user_time = 0;
+ account_user_time(tsk, utime);
+}
+
+static void account_process_time(struct pt_regs *regs)
+{
+ int cpu = smp_processor_id();
+
+ account_process_vtime(current);
+ run_local_timers();
+ if (rcu_pending(cpu))
+ rcu_check_callbacks(cpu, user_mode(regs));
+ scheduler_tick();
+ run_posix_cpu_timers(current);
+}
+
+#ifdef CONFIG_PPC_SPLPAR
+/*
+ * Stuff for accounting stolen time.
+ */
+struct cpu_purr_data {
+ int initialized; /* thread is running */
+ u64 tb; /* last TB value read */
+ u64 purr; /* last PURR value read */
+ spinlock_t lock;
+};
+
+static DEFINE_PER_CPU(struct cpu_purr_data, cpu_purr_data);
+
+static void snapshot_tb_and_purr(void *data)
+{
+ struct cpu_purr_data *p = &__get_cpu_var(cpu_purr_data);
+
+ p->tb = mftb();
+ p->purr = mfspr(SPRN_PURR);
+ wmb();
+ p->initialized = 1;
+}
+
+/*
+ * Called during boot when all cpus have come up.
+ */
+void snapshot_timebases(void)
+{
+ int cpu;
+
+ if (!cpu_has_feature(CPU_FTR_PURR))
+ return;
+ for_each_possible_cpu(cpu)
+ spin_lock_init(&per_cpu(cpu_purr_data, cpu).lock);
+ on_each_cpu(snapshot_tb_and_purr, NULL, 0, 1);
+}
+
+void calculate_steal_time(void)
+{
+ u64 tb, purr;
+ s64 stolen;
+ struct cpu_purr_data *pme;
+
+ if (!cpu_has_feature(CPU_FTR_PURR))
+ return;
+ pme = &per_cpu(cpu_purr_data, smp_processor_id());
+ if (!pme->initialized)
+ return; /* this can happen in early boot */
+ spin_lock(&pme->lock);
+ tb = mftb();
+ purr = mfspr(SPRN_PURR);
+ stolen = (tb - pme->tb) - (purr - pme->purr);
+ if (stolen > 0)
+ account_steal_time(current, stolen);
+ pme->tb = tb;
+ pme->purr = purr;
+ spin_unlock(&pme->lock);
+}
+
+/*
+ * Must be called before the cpu is added to the online map when
+ * a cpu is being brought up at runtime.
+ */
+static void snapshot_purr(void)
+{
+ struct cpu_purr_data *pme;
+ unsigned long flags;
+
+ if (!cpu_has_feature(CPU_FTR_PURR))
+ return;
+ pme = &per_cpu(cpu_purr_data, smp_processor_id());
+ spin_lock_irqsave(&pme->lock, flags);
+ pme->tb = mftb();
+ pme->purr = mfspr(SPRN_PURR);
+ pme->initialized = 1;
+ spin_unlock_irqrestore(&pme->lock, flags);
+}
+
+#endif /* CONFIG_PPC_SPLPAR */
+
+#else /* ! CONFIG_VIRT_CPU_ACCOUNTING */
+#define calc_cputime_factors()
+#define account_process_time(regs) update_process_times(user_mode(regs))
+#define calculate_steal_time() do { } while (0)
+#endif
+
+#if !(defined(CONFIG_VIRT_CPU_ACCOUNTING) && defined(CONFIG_PPC_SPLPAR))
+#define snapshot_purr() do { } while (0)
+#endif
+
+/*
+ * Called when a cpu comes up after the system has finished booting,
+ * i.e. as a result of a hotplug cpu action.
+ */
+void snapshot_timebase(void)
+{
+ __get_cpu_var(last_jiffy) = get_tb();
+ snapshot_purr();
+}
void __delay(unsigned long loops)
{
/*
* This version of gettimeofday has microsecond resolution.
*/
-static inline void __do_gettimeofday(struct timeval *tv, u64 tb_val)
+static inline void __do_gettimeofday(struct timeval *tv)
{
unsigned long sec, usec;
u64 tb_ticks, xsec;
* without a divide (and in fact, without a multiply)
*/
temp_varp = do_gtod.varp;
- tb_ticks = tb_val - temp_varp->tb_orig_stamp;
+
+ /* Sampling the time base must be done after loading
+ * do_gtod.varp in order to avoid racing with update_gtod.
+ */
+ data_barrier(temp_varp);
+ tb_ticks = get_tb() - temp_varp->tb_orig_stamp;
temp_tb_to_xs = temp_varp->tb_to_xs;
temp_stamp_xsec = temp_varp->stamp_xsec;
xsec = temp_stamp_xsec + mulhdu(tb_ticks, temp_tb_to_xs);
do {
seq = read_seqbegin_irqsave(&xtime_lock, flags);
sec = xtime.tv_sec;
- nsec = xtime.tv_nsec + tb_ticks_since(tb_last_stamp);
+ nsec = xtime.tv_nsec + tb_ticks_since(tb_last_jiffy);
} while (read_seqretry_irqrestore(&xtime_lock, seq, flags));
usec = nsec / 1000;
while (usec >= 1000000) {
tv->tv_usec = usec;
return;
}
- __do_gettimeofday(tv, get_tb());
+ __do_gettimeofday(tv);
}
EXPORT_SYMBOL(do_gettimeofday);
new_tb_ticks_per_jiffy, sign, tick_diff );
tb_ticks_per_jiffy = new_tb_ticks_per_jiffy;
tb_ticks_per_sec = new_tb_ticks_per_sec;
+ calc_cputime_factors();
div128_by_32( XSEC_PER_SEC, 0, tb_ticks_per_sec, &divres );
do_gtod.tb_ticks_per_sec = tb_ticks_per_sec;
tb_to_xs = divres.result_low;
*/
void timer_interrupt(struct pt_regs * regs)
{
+ struct pt_regs *old_regs;
int next_dec;
int cpu = smp_processor_id();
unsigned long ticks;
+ u64 tb_next_jiffy;
#ifdef CONFIG_PPC32
if (atomic_read(&ppc_n_lost_interrupts) != 0)
do_IRQ(regs);
#endif
+ old_regs = set_irq_regs(regs);
irq_enter();
- profile_tick(CPU_PROFILING, regs);
+ profile_tick(CPU_PROFILING);
+ calculate_steal_time();
#ifdef CONFIG_PPC_ISERIES
- get_lppaca()->int_dword.fields.decr_int = 0;
+ if (firmware_has_feature(FW_FEATURE_ISERIES))
+ get_lppaca()->int_dword.fields.decr_int = 0;
#endif
while ((ticks = tb_ticks_since(per_cpu(last_jiffy, cpu)))
* is the case.
*/
if (!cpu_is_offline(cpu))
- update_process_times(user_mode(regs));
+ account_process_time(regs);
/*
* No need to check whether cpu is offline here; boot_cpuid
continue;
write_seqlock(&xtime_lock);
- tb_last_jiffy += tb_ticks_per_jiffy;
- tb_last_stamp = per_cpu(last_jiffy, cpu);
- do_timer(regs);
- timer_recalc_offset(tb_last_jiffy);
- timer_check_rtc();
+ tb_next_jiffy = tb_last_jiffy + tb_ticks_per_jiffy;
+ if (per_cpu(last_jiffy, cpu) >= tb_next_jiffy) {
+ tb_last_jiffy = tb_next_jiffy;
+ do_timer(1);
+ timer_recalc_offset(tb_last_jiffy);
+ timer_check_rtc();
+ }
write_sequnlock(&xtime_lock);
}
set_dec(next_dec);
#ifdef CONFIG_PPC_ISERIES
- if (hvlpevent_is_pending())
- process_hvlpevents(regs);
+ if (firmware_has_feature(FW_FEATURE_ISERIES) && hvlpevent_is_pending())
+ process_hvlpevents();
#endif
#ifdef CONFIG_PPC64
#endif
irq_exit();
+ set_irq_regs(old_regs);
}
void wakeup_decrementer(void)
void __init smp_space_timers(unsigned int max_cpus)
{
int i;
+ unsigned long half = tb_ticks_per_jiffy / 2;
unsigned long offset = tb_ticks_per_jiffy / max_cpus;
- unsigned long previous_tb = per_cpu(last_jiffy, boot_cpuid);
+ u64 previous_tb = per_cpu(last_jiffy, boot_cpuid);
/* make sure tb > per_cpu(last_jiffy, cpu) for all cpus always */
previous_tb -= tb_ticks_per_jiffy;
- for_each_cpu(i) {
- if (i != boot_cpuid) {
+ /*
+ * The stolen time calculation for POWER5 shared-processor LPAR
+ * systems works better if the two threads' timebase interrupts
+ * are staggered by half a jiffy with respect to each other.
+ */
+ for_each_possible_cpu(i) {
+ if (i == boot_cpuid)
+ continue;
+ if (i == (boot_cpuid ^ 1))
+ per_cpu(last_jiffy, i) =
+ per_cpu(last_jiffy, boot_cpuid) - half;
+ else if (i & 1)
+ per_cpu(last_jiffy, i) =
+ per_cpu(last_jiffy, i ^ 1) + half;
+ else {
previous_tb += offset;
per_cpu(last_jiffy, i) = previous_tb;
}
* settimeofday to perform this operation.
*/
#ifdef CONFIG_PPC_ISERIES
- if (first_settimeofday) {
+ if (firmware_has_feature(FW_FEATURE_ISERIES) && first_settimeofday) {
iSeries_tb_recal();
first_settimeofday = 0;
}
/*
* Subtract off the number of nanoseconds since the
* beginning of the last tick.
- * Note that since we don't increment jiffies_64 anywhere other
- * than in do_timer (since we don't have a lost tick problem),
- * wall_jiffies will always be the same as jiffies,
- * and therefore the (jiffies - wall_jiffies) computation
- * has been removed.
*/
- tb_delta = tb_ticks_since(tb_last_stamp);
+ tb_delta = tb_ticks_since(tb_last_jiffy);
tb_delta = mulhdu(tb_delta, do_gtod.varp->tb_to_xs); /* in xsec */
new_nsec -= SCALE_XSEC(tb_delta, 1000000000);
EXPORT_SYMBOL(do_settimeofday);
-void __init generic_calibrate_decr(void)
+static int __init get_freq(char *name, int cells, unsigned long *val)
{
struct device_node *cpu;
- unsigned int *fp;
- int node_found;
+ const unsigned int *fp;
+ int found = 0;
- /*
- * The cpu node should have a timebase-frequency property
- * to tell us the rate at which the decrementer counts.
- */
+ /* The cpu node should have timebase and clock frequency properties */
cpu = of_find_node_by_type(NULL, "cpu");
- ppc_tb_freq = DEFAULT_TB_FREQ; /* hardcoded default */
- node_found = 0;
if (cpu) {
- fp = (unsigned int *)get_property(cpu, "timebase-frequency",
- NULL);
+ fp = get_property(cpu, name, NULL);
if (fp) {
- node_found = 1;
- ppc_tb_freq = *fp;
+ found = 1;
+ *val = of_read_ulong(fp, cells);
}
+
+ of_node_put(cpu);
}
- if (!node_found)
+
+ return found;
+}
+
+void __init generic_calibrate_decr(void)
+{
+ ppc_tb_freq = DEFAULT_TB_FREQ; /* hardcoded default */
+
+ if (!get_freq("ibm,extended-timebase-frequency", 2, &ppc_tb_freq) &&
+ !get_freq("timebase-frequency", 1, &ppc_tb_freq)) {
+
printk(KERN_ERR "WARNING: Estimating decrementer frequency "
"(not found)\n");
+ }
- ppc_proc_freq = DEFAULT_PROC_FREQ;
- node_found = 0;
- if (cpu) {
- fp = (unsigned int *)get_property(cpu, "clock-frequency",
- NULL);
- if (fp) {
- node_found = 1;
- ppc_proc_freq = *fp;
- }
+ ppc_proc_freq = DEFAULT_PROC_FREQ; /* hardcoded default */
+
+ if (!get_freq("ibm,extended-clock-frequency", 2, &ppc_proc_freq) &&
+ !get_freq("clock-frequency", 1, &ppc_proc_freq)) {
+
+ printk(KERN_ERR "WARNING: Estimating processor frequency "
+ "(not found)\n");
}
+
#ifdef CONFIG_BOOKE
/* Set the time base to zero */
mtspr(SPRN_TBWL, 0);
/* Enable decrementer interrupt */
mtspr(SPRN_TCR, TCR_DIE);
#endif
- if (!node_found)
- printk(KERN_ERR "WARNING: Estimating processor frequency "
- "(not found)\n");
-
- of_node_put(cpu);
}
unsigned long get_boot_time(void)
if (__USE_RTC()) {
/* 601 processor: dec counts down by 128 every 128ns */
ppc_tb_freq = 1000000000;
- tb_last_stamp = get_rtcl();
- tb_last_jiffy = tb_last_stamp;
+ tb_last_jiffy = get_rtcl();
} else {
/* Normal PowerPC with timebase register */
ppc_md.calibrate_decr();
- printk(KERN_INFO "time_init: decrementer frequency = %lu.%.6lu MHz\n",
+ printk(KERN_DEBUG "time_init: decrementer frequency = %lu.%.6lu MHz\n",
ppc_tb_freq / 1000000, ppc_tb_freq % 1000000);
- printk(KERN_INFO "time_init: processor frequency = %lu.%.6lu MHz\n",
+ printk(KERN_DEBUG "time_init: processor frequency = %lu.%.6lu MHz\n",
ppc_proc_freq / 1000000, ppc_proc_freq % 1000000);
- tb_last_stamp = tb_last_jiffy = get_tb();
+ tb_last_jiffy = get_tb();
}
tb_ticks_per_jiffy = ppc_tb_freq / HZ;
tb_ticks_per_sec = ppc_tb_freq;
tb_ticks_per_usec = ppc_tb_freq / 1000000;
tb_to_us = mulhwu_scale_factor(ppc_tb_freq, 1000000);
+ calc_cputime_factors();
/*
* Calculate the length of each tick in ns. It will not be
tb_to_ns_scale = scale;
tb_to_ns_shift = shift;
-#ifdef CONFIG_PPC_ISERIES
- if (!piranha_simulator)
-#endif
- tm = get_boot_time();
+ tm = get_boot_time();
write_seqlock_irqsave(&xtime_lock, flags);
do_gtod.varp = &do_gtod.vars[0];
do_gtod.var_idx = 0;
do_gtod.varp->tb_orig_stamp = tb_last_jiffy;
- __get_cpu_var(last_jiffy) = tb_last_stamp;
+ __get_cpu_var(last_jiffy) = tb_last_jiffy;
do_gtod.varp->stamp_xsec = (u64) xtime.tv_sec * XSEC_PER_SEC;
do_gtod.tb_ticks_per_sec = tb_ticks_per_sec;
do_gtod.varp->tb_to_xs = tb_to_xs;
git://git.onelab.eu / linux-2.6.git / blobdiff