Minki/linux
1
0
Fork 1
mirror of https://github.com/torvalds/linux.git synced 2024-11-22 12:11:40 +00:00
Code Issues Packages Projects Releases Wiki Activity

sched: Make task->start_time nanoseconds based

Browse Source 
Simplify the timespec to nsec/usec conversions.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: John Stultz <john.stultz@linaro.org>
This commit is contained in:
Thomas Gleixner 2014-07-16 21:04:34 +00:00 committed by John Stultz
parent 57e0be041d
commit ccbf62d8a2
4 changed files with 14 additions and 19 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
include/linux/sched.h
View File

@ -1367,7 +1367,7 @@ struct task_struct {
} vtime_snap_whence;
#endif
unsigned long nvcsw, nivcsw; /* context switch counts */
struct timespec start_time; /* monotonic time */
u64 start_time; /* monotonic time in nsec */
u64 real_start_time; /* boot based time in nsec */
/* mm fault and swap info: this can arguably be seen as either mm-specific or thread-specific */
unsigned long min_flt, maj_flt;

10
kernel/acct.c
View File

@ -458,9 +458,7 @@ static void do_acct_process(struct bsd_acct_struct *acct,
acct_t ac;
mm_segment_t fs;
unsigned long flim;
u64 elapsed;
u64 run_time;
struct timespec uptime;
u64 elapsed, run_time;
struct tty_struct *tty;
const struct cred *orig_cred;
@ -484,10 +482,8 @@ static void do_acct_process(struct bsd_acct_struct *acct,
strlcpy(ac.ac_comm, current->comm, sizeof(ac.ac_comm));
/* calculate run_time in nsec*/
ktime_get_ts(&uptime);
run_time = (u64)uptime.tv_sec*NSEC_PER_SEC + uptime.tv_nsec;
run_time -= (u64)current->group_leader->start_time.tv_sec * NSEC_PER_SEC
+ current->group_leader->start_time.tv_nsec;
run_time = ktime_get_ns();
run_time -= current->group_leader->start_time;
/* convert nsec -> AHZ */
elapsed = nsec_to_AHZ(run_time);
#if ACCT_VERSION==3

2
kernel/fork.c
View File

@ -1262,7 +1262,7 @@ static struct task_struct *copy_process(unsigned long clone_flags,
posix_cpu_timers_init(p);
ktime_get_ts(&p->start_time);
p->start_time = ktime_get_ns();
p->real_start_time = ktime_get_boot_ns();
p->io_context = NULL;
p->audit_context = NULL;

19
kernel/tsacct.c
View File

@ -31,20 +31,19 @@ void bacct_add_tsk(struct user_namespace *user_ns,
struct taskstats *stats, struct task_struct *tsk)
{
const struct cred *tcred;
struct timespec uptime, ts;
cputime_t utime, stime, utimescaled, stimescaled;
u64 ac_etime;
u64 delta;
BUILD_BUG_ON(TS_COMM_LEN < TASK_COMM_LEN);
/* calculate task elapsed time in timespec */
ktime_get_ts(&uptime);
ts = timespec_sub(uptime, tsk->start_time);
/* rebase elapsed time to usec (should never be negative) */
ac_etime = timespec_to_ns(&ts);
do_div(ac_etime, NSEC_PER_USEC);
stats->ac_etime = ac_etime;
stats->ac_btime = get_seconds() - ts.tv_sec;
/* calculate task elapsed time in nsec */
delta = ktime_get_ns() - tsk->start_time;
/* Convert to micro seconds */
do_div(delta, NSEC_PER_USEC);
stats->ac_etime = delta;
/* Convert to seconds for btime */
do_div(delta, USEC_PER_SEC);
stats->ac_btime = get_seconds() - delta;
if (thread_group_leader(tsk)) {
stats->ac_exitcode = tsk->exit_code;
if (tsk->flags & PF_FORKNOEXEC)