[PATCH 3/3] sched/cputime: Protect other sum_exec_runtime reads on 32 bit cpus
From: Stanislaw Gruszka
Date: Thu Sep 01 2016 - 05:32:10 EST
We protect sum_exec_runtime variable against inconsistency when reading
it on thread_group_cputime(), but we also read it on other places not
called with task_rq_lock() taken.
Patch changes that, except file kernel/sched/debug.c , where we also
read some other u64 variables (vrunime, exec_start) without protection.
But since this is for debug purpose and inconsistency is very very
improbable, we can ignore it.
Signed-off-by: Stanislaw Gruszka <sgruszka@xxxxxxxxxx>
---
fs/proc/base.c | 2 +-
kernel/delayacct.c | 2 +-
kernel/exit.c | 2 +-
kernel/sched/cputime.c | 2 +-
kernel/time/posix-cpu-timers.c | 4 ++--
5 files changed, 6 insertions(+), 6 deletions(-)
diff --git a/fs/proc/base.c b/fs/proc/base.c
index e9ff186..8118d97 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -505,7 +505,7 @@ static int proc_pid_schedstat(struct seq_file *m, struct pid_namespace *ns,
seq_printf(m, "0 0 0\n");
else
seq_printf(m, "%llu %llu %lu\n",
- (unsigned long long)task->se.sum_exec_runtime,
+ (unsigned long long)read_sum_exec_runtime(task),
(unsigned long long)task->sched_info.run_delay,
task->sched_info.pcount);
diff --git a/kernel/delayacct.c b/kernel/delayacct.c
index 435c14a..023b2ca 100644
--- a/kernel/delayacct.c
+++ b/kernel/delayacct.c
@@ -104,7 +104,7 @@ int __delayacct_add_tsk(struct taskstats *d, struct task_struct *tsk)
*/
t1 = tsk->sched_info.pcount;
t2 = tsk->sched_info.run_delay;
- t3 = tsk->se.sum_exec_runtime;
+ t3 = read_sum_exec_runtime(tsk);
d->cpu_count += t1;
diff --git a/kernel/exit.c b/kernel/exit.c
index 2f974ae..a46f96f 100644
--- a/kernel/exit.c
+++ b/kernel/exit.c
@@ -134,7 +134,7 @@ static void __exit_signal(struct task_struct *tsk)
sig->inblock += task_io_get_inblock(tsk);
sig->oublock += task_io_get_oublock(tsk);
task_io_accounting_add(&sig->ioac, &tsk->ioac);
- sig->sum_sched_runtime += tsk->se.sum_exec_runtime;
+ sig->sum_sched_runtime += read_sum_exec_runtime(tsk);
sig->nr_threads--;
__unhash_process(tsk, group_dead);
write_sequnlock(&sig->stats_lock);
diff --git a/kernel/sched/cputime.c b/kernel/sched/cputime.c
index 026c1c4..cd1dd43 100644
--- a/kernel/sched/cputime.c
+++ b/kernel/sched/cputime.c
@@ -682,7 +682,7 @@ out:
void task_cputime_adjusted(struct task_struct *p, cputime_t *ut, cputime_t *st)
{
struct task_cputime cputime = {
- .sum_exec_runtime = p->se.sum_exec_runtime,
+ .sum_exec_runtime = read_sum_exec_runtime(p),
};
task_cputime(p, &cputime.utime, &cputime.stime);
diff --git a/kernel/time/posix-cpu-timers.c b/kernel/time/posix-cpu-timers.c
index 4d8466b..b1e7275 100644
--- a/kernel/time/posix-cpu-timers.c
+++ b/kernel/time/posix-cpu-timers.c
@@ -849,7 +849,7 @@ static void check_thread_timers(struct task_struct *tsk,
tsk_expires->virt_exp = expires_to_cputime(expires);
tsk_expires->sched_exp = check_timers_list(++timers, firing,
- tsk->se.sum_exec_runtime);
+ read_sum_exec_runtime(tsk));
/*
* Check for the special case thread timers.
@@ -1116,7 +1116,7 @@ static inline int fastpath_timer_check(struct task_struct *tsk)
struct task_cputime task_sample;
task_cputime(tsk, &task_sample.utime, &task_sample.stime);
- task_sample.sum_exec_runtime = tsk->se.sum_exec_runtime;
+ task_sample.sum_exec_runtime = read_sum_exec_runtime(tsk);
if (task_cputime_expired(&task_sample, &tsk->cputime_expires))
return 1;
}
--
1.8.3.1