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authorJens Axboe <axboe@kernel.dk>2019-02-15 08:43:59 -0700
committerJens Axboe <axboe@kernel.dk>2019-02-15 08:43:59 -0700
commit6fb845f0e78de19eaaf6a2d351702474e44b6a9e (patch)
tree94c6474b38d8f59d8f0de0151053283812e456c6 /kernel/sched/psi.c
parent56d18f62f556b80105e38e7975975cf7465aae3e (diff)
parentd13937116f1e82bf508a6325111b322c30c85eb9 (diff)
Merge tag 'v5.0-rc6' into for-5.1/block
Pull in 5.0-rc6 to avoid a dumb merge conflict with fs/iomap.c. This is needed since io_uring is now based on the block branch, to avoid a conflict between the multi-page bvecs and the bits of io_uring that touch the core block parts. * tag 'v5.0-rc6': (525 commits) Linux 5.0-rc6 x86/mm: Make set_pmd_at() paravirt aware MAINTAINERS: Update the ocores i2c bus driver maintainer, etc blk-mq: remove duplicated definition of blk_mq_freeze_queue Blk-iolatency: warn on negative inflight IO counter blk-iolatency: fix IO hang due to negative inflight counter MAINTAINERS: unify reference to xen-devel list x86/mm/cpa: Fix set_mce_nospec() futex: Handle early deadlock return correctly futex: Fix barrier comment net: dsa: b53: Fix for failure when irq is not defined in dt blktrace: Show requests without sector mips: cm: reprime error cause mips: loongson64: remove unreachable(), fix loongson_poweroff(). sit: check if IPv6 enabled before calling ip6_err_gen_icmpv6_unreach() geneve: should not call rt6_lookup() when ipv6 was disabled KVM: nVMX: unconditionally cancel preemption timer in free_nested (CVE-2019-7221) KVM: x86: work around leak of uninitialized stack contents (CVE-2019-7222) kvm: fix kvm_ioctl_create_device() reference counting (CVE-2019-6974) signal: Better detection of synchronous signals ...
Diffstat (limited to 'kernel/sched/psi.c')
-rw-r--r--kernel/sched/psi.c21
1 files changed, 17 insertions, 4 deletions
diff --git a/kernel/sched/psi.c b/kernel/sched/psi.c
index fe24de3fbc93..c3484785b179 100644
--- a/kernel/sched/psi.c
+++ b/kernel/sched/psi.c
@@ -124,6 +124,7 @@
* sampling of the aggregate task states would be.
*/
+#include "../workqueue_internal.h"
#include <linux/sched/loadavg.h>
#include <linux/seq_file.h>
#include <linux/proc_fs.h>
@@ -480,9 +481,6 @@ static void psi_group_change(struct psi_group *group, int cpu,
groupc->tasks[t]++;
write_seqcount_end(&groupc->seq);
-
- if (!delayed_work_pending(&group->clock_work))
- schedule_delayed_work(&group->clock_work, PSI_FREQ);
}
static struct psi_group *iterate_groups(struct task_struct *task, void **iter)
@@ -513,6 +511,7 @@ void psi_task_change(struct task_struct *task, int clear, int set)
{
int cpu = task_cpu(task);
struct psi_group *group;
+ bool wake_clock = true;
void *iter = NULL;
if (!task->pid)
@@ -530,8 +529,22 @@ void psi_task_change(struct task_struct *task, int clear, int set)
task->psi_flags &= ~clear;
task->psi_flags |= set;
- while ((group = iterate_groups(task, &iter)))
+ /*
+ * Periodic aggregation shuts off if there is a period of no
+ * task changes, so we wake it back up if necessary. However,
+ * don't do this if the task change is the aggregation worker
+ * itself going to sleep, or we'll ping-pong forever.
+ */
+ if (unlikely((clear & TSK_RUNNING) &&
+ (task->flags & PF_WQ_WORKER) &&
+ wq_worker_last_func(task) == psi_update_work))
+ wake_clock = false;
+
+ while ((group = iterate_groups(task, &iter))) {
psi_group_change(group, cpu, clear, set);
+ if (wake_clock && !delayed_work_pending(&group->clock_work))
+ schedule_delayed_work(&group->clock_work, PSI_FREQ);
+ }
}
void psi_memstall_tick(struct task_struct *task, int cpu)