This adds the RUSAGE_THREAD option for the getrusage system call.
Solaris calls this RUSAGE_LWP and uses the same value (1).
That name is not a natural one for Linux, but we keep it as an alias.
Signed-off-by: Roland McGrath <roland@redhat.com>
---
include/linux/resource.h | 2 ++
kernel/sys.c | 31 ++++++++++++++++++++++---------
2 files changed, 24 insertions(+), 9 deletions(-)
diff --git a/include/linux/resource.h b/include/linux/resource.h
index ae13db7..02b3377 100644
--- a/include/linux/resource.h
+++ b/include/linux/resource.h
@@ -19,6 +19,8 @@ struct task_struct;
#define RUSAGE_SELF 0
#define RUSAGE_CHILDREN (-1)
#define RUSAGE_BOTH (-2) /* sys_wait4() uses this */
+#define RUSAGE_THREAD 1 /* only the calling thread */
+#define RUSAGE_LWP RUSAGE_THREAD /* Solaris name for same */
struct rusage {
struct timeval ru_utime; /* user time used */
diff --git a/kernel/sys.c b/kernel/sys.c
index d1fe71e..6a62bc4 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -1554,6 +1554,19 @@ out:
*
*/
+static void accumulate_thread_rusage(struct task_struct *t, struct rusage *r,
+ cputime_t *utimep, cputime_t *stimep)
+{
+ *utimep = cputime_add(*utimep, t->utime);
+ *stimep = cputime_add(*stimep, t->stime);
+ r->ru_nvcsw += t->nvcsw;
+ r->ru_nivcsw += t->nivcsw;
+ r->ru_minflt += t->min_flt;
+ r->ru_majflt += t->maj_flt;
+ r->ru_inblock += task_io_get_inblock(t);
+ r->ru_oublock += task_io_get_oublock(t);
+}
+
static void k_getrusage(struct task_struct *p, int who, struct rusage *r)
{
struct task_struct *t;
@@ -1563,6 +1576,11 @@ static void k_getrusage(struct task_struct *p, int who, struct rusage *r)
memset((char *) r, 0, sizeof *r);
utime = stime = cputime_zero;
+ if (who == RUSAGE_THREAD) {
+ accumulate_thread_rusage(p, r, &utime, &stime);
+ goto out;
+ }
+
rcu_read_lock();
if (!lock_task_sighand(p, &flags)) {
rcu_read_unlock();
@@ -1595,14 +1613,7 @@ static void k_getrusage(struct task_struct *p, int who, struct rusage *r)
r->ru_oublock += p->signal->oublock;
t = p;
do {
- utime = cputime_add(utime, t->utime);
- stime = cputime_add(stime, t->stime);
- r->ru_nvcsw += t->nvcsw;
- r->ru_nivcsw += t->nivcsw;
- r->ru_minflt += t->min_flt;
- r->ru_majflt += t->maj_flt;
- r->ru_inblock += task_io_get_inblock(t);
- r->ru_oublock += task_io_get_oublock(t);
+ accumulate_thread_rusage(t, r, &utime, &stime);
t = next_thread(t);
} while (t != p);
break;
@@ -1614,6 +1625,7 @@ static void k_getrusage(struct task_struct *p, int who, struct rusage *r)
unlock_task_sighand(p, &flags);
rcu_read_unlock();
+out:
cputime_to_timeval(utime, &r->ru_utime);
cputime_to_timeval(stime, &r->ru_stime);
}
@@ -1627,7 +1639,8 @@ int getrusage(struct task_struct *p, int who, struct rusage __user *ru)
asmlinkage long sys_getrusage(int who, struct rusage __user *ru)
{
- if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN)
+ if (who != RUSAGE_SELF && who != RUSAGE_CHILDREN &&
+ who != RUSAGE_THREAD)
return -EINVAL;
return getrusage(current, who, ru);
}
--
