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gettimeofday: avoid per-cpu data in calculation

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Because it is difficult to safely update per-cpu data of other cpus in
settimeofday().
This commit is contained in:
NAKAMURA Gou
2015-10-15 15:16:10 +09:00
parent cad72a8562
commit 153a59a6f4
4 changed files with 43 additions and 41 deletions
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27
kernel/init.c
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@ -201,11 +201,21 @@ static void pc_test(void)
}
extern void ihk_mc_get_boot_time(unsigned long *tv_sec, unsigned long *tv_nsec);
extern unsigned long ihk_mc_get_ns_per_tsc(void);
static void time_init(void)
{
ihk_mc_get_boot_time(&cpu_local_var(tv_sec),
&cpu_local_var(tv_nsec));
cpu_local_var(last_tsc) = 0;
unsigned long tv_sec, tv_nsec;
unsigned long ns_per_kclock;
ihk_mc_get_boot_time(&tv_sec, &tv_nsec);
ns_per_kclock = ihk_mc_get_ns_per_tsc();
origin_ts.tv_sec = tv_sec;
origin_ts.tv_nsec = tv_nsec;
clocks_per_sec = (1000L * NS_PER_SEC) / ns_per_kclock;
return;
}
static void rest_init(void)
@ -233,11 +243,9 @@ static void rest_init(void)
int host_ikc_inited = 0;
extern int num_processors;
extern void zero_tsc(void);
extern void update_cpu_local_time(void);
static void post_init(void)
{
int i;
cpu_enable_interrupt();
while (!host_ikc_inited) {
@ -253,16 +261,9 @@ static void post_init(void)
ihk_mc_spinlock_init(&syscall_lock);
}
/* Update time elapsed so far during boot, distribute the current
* date to all cores and zero TSC.
/* Zero TSC.
* All AP cores are wait spinning for ap_start() and they will zero
* their TSC immediatly. */
update_cpu_local_time();
cpu_local_var(last_tsc) = 0;
for (i = 0; i < num_processors; ++i) {
get_cpu_local_var(i)->tv_sec = cpu_local_var(tv_sec);
get_cpu_local_var(i)->tv_nsec = cpu_local_var(tv_nsec);
}
zero_tsc();
ap_start();