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-rw-r--r--kernel/fork.c32
-rw-r--r--kernel/kthread.c2
-rw-r--r--kernel/rcu/tree.c9
-rw-r--r--kernel/resource_kunit.c18
-rw-r--r--kernel/sched/core.c21
-rw-r--r--kernel/sched/ext.c32
-rw-r--r--kernel/sched/psi.c26
-rw-r--r--kernel/sched/sched.h3
-rw-r--r--kernel/trace/ring_buffer.c9
-rw-r--r--kernel/trace/trace.c15
-rw-r--r--kernel/trace/trace_hwlat.c2
-rw-r--r--kernel/trace/trace_osnoise.c22
12 files changed, 118 insertions, 73 deletions
diff --git a/kernel/fork.c b/kernel/fork.c
index 60c0b4868fd4..89ceb4a68af2 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -1756,33 +1756,30 @@ static int copy_files(unsigned long clone_flags, struct task_struct *tsk,
int no_files)
{
struct files_struct *oldf, *newf;
- int error = 0;
/*
* A background process may not have any files ...
*/
oldf = current->files;
if (!oldf)
- goto out;
+ return 0;
if (no_files) {
tsk->files = NULL;
- goto out;
+ return 0;
}
if (clone_flags & CLONE_FILES) {
atomic_inc(&oldf->count);
- goto out;
+ return 0;
}
- newf = dup_fd(oldf, NR_OPEN_MAX, &error);
- if (!newf)
- goto out;
+ newf = dup_fd(oldf, NULL);
+ if (IS_ERR(newf))
+ return PTR_ERR(newf);
tsk->files = newf;
- error = 0;
-out:
- return error;
+ return 0;
}
static int copy_sighand(unsigned long clone_flags, struct task_struct *tsk)
@@ -3238,17 +3235,16 @@ static int unshare_fs(unsigned long unshare_flags, struct fs_struct **new_fsp)
/*
* Unshare file descriptor table if it is being shared
*/
-int unshare_fd(unsigned long unshare_flags, unsigned int max_fds,
- struct files_struct **new_fdp)
+static int unshare_fd(unsigned long unshare_flags, struct files_struct **new_fdp)
{
struct files_struct *fd = current->files;
- int error = 0;
if ((unshare_flags & CLONE_FILES) &&
(fd && atomic_read(&fd->count) > 1)) {
- *new_fdp = dup_fd(fd, max_fds, &error);
- if (!*new_fdp)
- return error;
+ fd = dup_fd(fd, NULL);
+ if (IS_ERR(fd))
+ return PTR_ERR(fd);
+ *new_fdp = fd;
}
return 0;
@@ -3306,7 +3302,7 @@ int ksys_unshare(unsigned long unshare_flags)
err = unshare_fs(unshare_flags, &new_fs);
if (err)
goto bad_unshare_out;
- err = unshare_fd(unshare_flags, NR_OPEN_MAX, &new_fd);
+ err = unshare_fd(unshare_flags, &new_fd);
if (err)
goto bad_unshare_cleanup_fs;
err = unshare_userns(unshare_flags, &new_cred);
@@ -3398,7 +3394,7 @@ int unshare_files(void)
struct files_struct *old, *copy = NULL;
int error;
- error = unshare_fd(CLONE_FILES, NR_OPEN_MAX, &copy);
+ error = unshare_fd(CLONE_FILES, &copy);
if (error || !copy)
return error;
diff --git a/kernel/kthread.c b/kernel/kthread.c
index db4ceb0f503c..9bb36897b6c6 100644
--- a/kernel/kthread.c
+++ b/kernel/kthread.c
@@ -623,6 +623,8 @@ void kthread_unpark(struct task_struct *k)
{
struct kthread *kthread = to_kthread(k);
+ if (!test_bit(KTHREAD_SHOULD_PARK, &kthread->flags))
+ return;
/*
* Newly created kthread was parked when the CPU was offline.
* The binding was lost and we need to set it again.
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index a60616e69b66..b1f883fcd918 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -3607,11 +3607,12 @@ kvfree_rcu_queue_batch(struct kfree_rcu_cpu *krcp)
}
// One work is per one batch, so there are three
- // "free channels", the batch can handle. It can
- // be that the work is in the pending state when
- // channels have been detached following by each
- // other.
+ // "free channels", the batch can handle. Break
+ // the loop since it is done with this CPU thus
+ // queuing an RCU work is _always_ success here.
queued = queue_rcu_work(system_unbound_wq, &krwp->rcu_work);
+ WARN_ON_ONCE(!queued);
+ break;
}
}
diff --git a/kernel/resource_kunit.c b/kernel/resource_kunit.c
index 42d2d8d20f5d..b8ef75b99eb2 100644
--- a/kernel/resource_kunit.c
+++ b/kernel/resource_kunit.c
@@ -169,6 +169,8 @@ static void resource_test_intersection(struct kunit *test)
#define RES_TEST_RAM3_SIZE SZ_1M
#define RES_TEST_TOTAL_SIZE ((RES_TEST_WIN1_OFFSET + RES_TEST_WIN1_SIZE))
+KUNIT_DEFINE_ACTION_WRAPPER(kfree_wrapper, kfree, const void *);
+
static void remove_free_resource(void *ctx)
{
struct resource *res = (struct resource *)ctx;
@@ -177,6 +179,14 @@ static void remove_free_resource(void *ctx)
kfree(res);
}
+static void resource_test_add_action_or_abort(
+ struct kunit *test, void (*action)(void *), void *ctx)
+{
+ KUNIT_ASSERT_EQ_MSG(test, 0,
+ kunit_add_action_or_reset(test, action, ctx),
+ "Fail to add action");
+}
+
static void resource_test_request_region(struct kunit *test, struct resource *parent,
resource_size_t start, resource_size_t size,
const char *name, unsigned long flags)
@@ -185,7 +195,7 @@ static void resource_test_request_region(struct kunit *test, struct resource *pa
res = __request_region(parent, start, size, name, flags);
KUNIT_ASSERT_NOT_NULL(test, res);
- kunit_add_action_or_reset(test, remove_free_resource, res);
+ resource_test_add_action_or_abort(test, remove_free_resource, res);
}
static void resource_test_insert_resource(struct kunit *test, struct resource *parent,
@@ -202,11 +212,11 @@ static void resource_test_insert_resource(struct kunit *test, struct resource *p
res->end = start + size - 1;
res->flags = flags;
if (insert_resource(parent, res)) {
- kfree(res);
+ resource_test_add_action_or_abort(test, kfree_wrapper, res);
KUNIT_FAIL_AND_ABORT(test, "Fail to insert resource %pR\n", res);
}
- kunit_add_action_or_reset(test, remove_free_resource, res);
+ resource_test_add_action_or_abort(test, remove_free_resource, res);
}
static void resource_test_region_intersects(struct kunit *test)
@@ -220,7 +230,7 @@ static void resource_test_region_intersects(struct kunit *test)
"test resources");
KUNIT_ASSERT_NOT_ERR_OR_NULL(test, parent);
start = parent->start;
- kunit_add_action_or_reset(test, remove_free_resource, parent);
+ resource_test_add_action_or_abort(test, remove_free_resource, parent);
resource_test_request_region(test, parent, start + RES_TEST_RAM0_OFFSET,
RES_TEST_RAM0_SIZE, "Test System RAM 0", flags);
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 43e453ab7e20..aeb595514461 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -3518,14 +3518,16 @@ out:
* The caller (fork, wakeup) owns p->pi_lock, ->cpus_ptr is stable.
*/
static inline
-int select_task_rq(struct task_struct *p, int cpu, int wake_flags)
+int select_task_rq(struct task_struct *p, int cpu, int *wake_flags)
{
lockdep_assert_held(&p->pi_lock);
- if (p->nr_cpus_allowed > 1 && !is_migration_disabled(p))
- cpu = p->sched_class->select_task_rq(p, cpu, wake_flags);
- else
+ if (p->nr_cpus_allowed > 1 && !is_migration_disabled(p)) {
+ cpu = p->sched_class->select_task_rq(p, cpu, *wake_flags);
+ *wake_flags |= WF_RQ_SELECTED;
+ } else {
cpu = cpumask_any(p->cpus_ptr);
+ }
/*
* In order not to call set_task_cpu() on a blocking task we need
@@ -3659,6 +3661,8 @@ ttwu_do_activate(struct rq *rq, struct task_struct *p, int wake_flags,
rq->nr_uninterruptible--;
#ifdef CONFIG_SMP
+ if (wake_flags & WF_RQ_SELECTED)
+ en_flags |= ENQUEUE_RQ_SELECTED;
if (wake_flags & WF_MIGRATED)
en_flags |= ENQUEUE_MIGRATED;
else
@@ -4120,6 +4124,8 @@ int try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags)
guard(preempt)();
int cpu, success = 0;
+ wake_flags |= WF_TTWU;
+
if (p == current) {
/*
* We're waking current, this means 'p->on_rq' and 'task_cpu(p)
@@ -4252,7 +4258,7 @@ int try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags)
*/
smp_cond_load_acquire(&p->on_cpu, !VAL);
- cpu = select_task_rq(p, p->wake_cpu, wake_flags | WF_TTWU);
+ cpu = select_task_rq(p, p->wake_cpu, &wake_flags);
if (task_cpu(p) != cpu) {
if (p->in_iowait) {
delayacct_blkio_end(p);
@@ -4793,6 +4799,7 @@ void wake_up_new_task(struct task_struct *p)
{
struct rq_flags rf;
struct rq *rq;
+ int wake_flags = WF_FORK;
raw_spin_lock_irqsave(&p->pi_lock, rf.flags);
WRITE_ONCE(p->__state, TASK_RUNNING);
@@ -4807,7 +4814,7 @@ void wake_up_new_task(struct task_struct *p)
*/
p->recent_used_cpu = task_cpu(p);
rseq_migrate(p);
- __set_task_cpu(p, select_task_rq(p, task_cpu(p), WF_FORK));
+ __set_task_cpu(p, select_task_rq(p, task_cpu(p), &wake_flags));
#endif
rq = __task_rq_lock(p, &rf);
update_rq_clock(rq);
@@ -4815,7 +4822,7 @@ void wake_up_new_task(struct task_struct *p)
activate_task(rq, p, ENQUEUE_NOCLOCK | ENQUEUE_INITIAL);
trace_sched_wakeup_new(p);
- wakeup_preempt(rq, p, WF_FORK);
+ wakeup_preempt(rq, p, wake_flags);
#ifdef CONFIG_SMP
if (p->sched_class->task_woken) {
/*
diff --git a/kernel/sched/ext.c b/kernel/sched/ext.c
index 3cd7c50a51c5..410a4df8a121 100644
--- a/kernel/sched/ext.c
+++ b/kernel/sched/ext.c
@@ -625,6 +625,10 @@ struct sched_ext_ops {
/**
* exit - Clean up after the BPF scheduler
* @info: Exit info
+ *
+ * ops.exit() is also called on ops.init() failure, which is a bit
+ * unusual. This is to allow rich reporting through @info on how
+ * ops.init() failed.
*/
void (*exit)(struct scx_exit_info *info);
@@ -692,6 +696,7 @@ enum scx_enq_flags {
/* expose select ENQUEUE_* flags as enums */
SCX_ENQ_WAKEUP = ENQUEUE_WAKEUP,
SCX_ENQ_HEAD = ENQUEUE_HEAD,
+ SCX_ENQ_CPU_SELECTED = ENQUEUE_RQ_SELECTED,
/* high 32bits are SCX specific */
@@ -4048,7 +4053,6 @@ static void scx_cgroup_exit(void)
percpu_rwsem_assert_held(&scx_cgroup_rwsem);
- WARN_ON_ONCE(!scx_cgroup_enabled);
scx_cgroup_enabled = false;
/*
@@ -4117,6 +4121,7 @@ static int scx_cgroup_init(void)
css->cgroup, &args);
if (ret) {
css_put(css);
+ scx_ops_error("ops.cgroup_init() failed (%d)", ret);
return ret;
}
tg->scx_flags |= SCX_TG_INITED;
@@ -5041,6 +5046,7 @@ static int scx_ops_enable(struct sched_ext_ops *ops, struct bpf_link *link)
if (ret) {
ret = ops_sanitize_err("init", ret);
cpus_read_unlock();
+ scx_ops_error("ops.init() failed (%d)", ret);
goto err_disable;
}
}
@@ -5150,8 +5156,8 @@ static int scx_ops_enable(struct sched_ext_ops *ops, struct bpf_link *link)
spin_lock_irq(&scx_tasks_lock);
scx_task_iter_exit(&sti);
spin_unlock_irq(&scx_tasks_lock);
- pr_err("sched_ext: ops.init_task() failed (%d) for %s[%d] while loading\n",
- ret, p->comm, p->pid);
+ scx_ops_error("ops.init_task() failed (%d) for %s[%d]",
+ ret, p->comm, p->pid);
goto err_disable_unlock_all;
}
@@ -5199,14 +5205,8 @@ static int scx_ops_enable(struct sched_ext_ops *ops, struct bpf_link *link)
scx_ops_bypass(false);
- /*
- * Returning an error code here would lose the recorded error
- * information. Exit indicating success so that the error is notified
- * through ops.exit() with all the details.
- */
if (!scx_ops_tryset_enable_state(SCX_OPS_ENABLED, SCX_OPS_ENABLING)) {
WARN_ON_ONCE(atomic_read(&scx_exit_kind) == SCX_EXIT_NONE);
- ret = 0;
goto err_disable;
}
@@ -5241,10 +5241,18 @@ err_disable_unlock_all:
scx_ops_bypass(false);
err_disable:
mutex_unlock(&scx_ops_enable_mutex);
- /* must be fully disabled before returning */
- scx_ops_disable(SCX_EXIT_ERROR);
+ /*
+ * Returning an error code here would not pass all the error information
+ * to userspace. Record errno using scx_ops_error() for cases
+ * scx_ops_error() wasn't already invoked and exit indicating success so
+ * that the error is notified through ops.exit() with all the details.
+ *
+ * Flush scx_ops_disable_work to ensure that error is reported before
+ * init completion.
+ */
+ scx_ops_error("scx_ops_enable() failed (%d)", ret);
kthread_flush_work(&scx_ops_disable_work);
- return ret;
+ return 0;
}
diff --git a/kernel/sched/psi.c b/kernel/sched/psi.c
index 020d58967d4e..84dad1511d1e 100644
--- a/kernel/sched/psi.c
+++ b/kernel/sched/psi.c
@@ -769,12 +769,13 @@ static void record_times(struct psi_group_cpu *groupc, u64 now)
}
static void psi_group_change(struct psi_group *group, int cpu,
- unsigned int clear, unsigned int set, u64 now,
+ unsigned int clear, unsigned int set,
bool wake_clock)
{
struct psi_group_cpu *groupc;
unsigned int t, m;
u32 state_mask;
+ u64 now;
lockdep_assert_rq_held(cpu_rq(cpu));
groupc = per_cpu_ptr(group->pcpu, cpu);
@@ -789,6 +790,7 @@ static void psi_group_change(struct psi_group *group, int cpu,
* SOME and FULL time these may have resulted in.
*/
write_seqcount_begin(&groupc->seq);
+ now = cpu_clock(cpu);
/*
* Start with TSK_ONCPU, which doesn't have a corresponding
@@ -899,18 +901,15 @@ void psi_task_change(struct task_struct *task, int clear, int set)
{
int cpu = task_cpu(task);
struct psi_group *group;
- u64 now;
if (!task->pid)
return;
psi_flags_change(task, clear, set);
- now = cpu_clock(cpu);
-
group = task_psi_group(task);
do {
- psi_group_change(group, cpu, clear, set, now, true);
+ psi_group_change(group, cpu, clear, set, true);
} while ((group = group->parent));
}
@@ -919,7 +918,6 @@ void psi_task_switch(struct task_struct *prev, struct task_struct *next,
{
struct psi_group *group, *common = NULL;
int cpu = task_cpu(prev);
- u64 now = cpu_clock(cpu);
if (next->pid) {
psi_flags_change(next, 0, TSK_ONCPU);
@@ -936,7 +934,7 @@ void psi_task_switch(struct task_struct *prev, struct task_struct *next,
break;
}
- psi_group_change(group, cpu, 0, TSK_ONCPU, now, true);
+ psi_group_change(group, cpu, 0, TSK_ONCPU, true);
} while ((group = group->parent));
}
@@ -974,7 +972,7 @@ void psi_task_switch(struct task_struct *prev, struct task_struct *next,
do {
if (group == common)
break;
- psi_group_change(group, cpu, clear, set, now, wake_clock);
+ psi_group_change(group, cpu, clear, set, wake_clock);
} while ((group = group->parent));
/*
@@ -986,7 +984,7 @@ void psi_task_switch(struct task_struct *prev, struct task_struct *next,
if ((prev->psi_flags ^ next->psi_flags) & ~TSK_ONCPU) {
clear &= ~TSK_ONCPU;
for (; group; group = group->parent)
- psi_group_change(group, cpu, clear, set, now, wake_clock);
+ psi_group_change(group, cpu, clear, set, wake_clock);
}
}
}
@@ -997,8 +995,8 @@ void psi_account_irqtime(struct rq *rq, struct task_struct *curr, struct task_st
int cpu = task_cpu(curr);
struct psi_group *group;
struct psi_group_cpu *groupc;
- u64 now, irq;
s64 delta;
+ u64 irq;
if (static_branch_likely(&psi_disabled))
return;
@@ -1011,7 +1009,6 @@ void psi_account_irqtime(struct rq *rq, struct task_struct *curr, struct task_st
if (prev && task_psi_group(prev) == group)
return;
- now = cpu_clock(cpu);
irq = irq_time_read(cpu);
delta = (s64)(irq - rq->psi_irq_time);
if (delta < 0)
@@ -1019,12 +1016,15 @@ void psi_account_irqtime(struct rq *rq, struct task_struct *curr, struct task_st
rq->psi_irq_time = irq;
do {
+ u64 now;
+
if (!group->enabled)
continue;
groupc = per_cpu_ptr(group->pcpu, cpu);
write_seqcount_begin(&groupc->seq);
+ now = cpu_clock(cpu);
record_times(groupc, now);
groupc->times[PSI_IRQ_FULL] += delta;
@@ -1223,11 +1223,9 @@ void psi_cgroup_restart(struct psi_group *group)
for_each_possible_cpu(cpu) {
struct rq *rq = cpu_rq(cpu);
struct rq_flags rf;
- u64 now;
rq_lock_irq(rq, &rf);
- now = cpu_clock(cpu);
- psi_group_change(group, cpu, 0, 0, now, true);
+ psi_group_change(group, cpu, 0, 0, true);
rq_unlock_irq(rq, &rf);
}
}
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index b1c3588a8f00..6085ef50febf 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -2292,6 +2292,7 @@ static inline int task_on_rq_migrating(struct task_struct *p)
#define WF_SYNC 0x10 /* Waker goes to sleep after wakeup */
#define WF_MIGRATED 0x20 /* Internal use, task got migrated */
#define WF_CURRENT_CPU 0x40 /* Prefer to move the wakee to the current CPU. */
+#define WF_RQ_SELECTED 0x80 /* ->select_task_rq() was called */
#ifdef CONFIG_SMP
static_assert(WF_EXEC == SD_BALANCE_EXEC);
@@ -2334,6 +2335,7 @@ extern const u32 sched_prio_to_wmult[40];
* ENQUEUE_HEAD - place at front of runqueue (tail if not specified)
* ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline)
* ENQUEUE_MIGRATED - the task was migrated during wakeup
+ * ENQUEUE_RQ_SELECTED - ->select_task_rq() was called
*
*/
@@ -2360,6 +2362,7 @@ extern const u32 sched_prio_to_wmult[40];
#define ENQUEUE_INITIAL 0x80
#define ENQUEUE_MIGRATING 0x100
#define ENQUEUE_DELAYED 0x200
+#define ENQUEUE_RQ_SELECTED 0x400
#define RETRY_TASK ((void *)-1UL)
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 77dc0b25140e..fb04445f92c3 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -2337,9 +2337,12 @@ static struct trace_buffer *alloc_buffer(unsigned long size, unsigned flags,
if (!buffer->buffers[cpu])
goto fail_free_buffers;
- ret = cpuhp_state_add_instance(CPUHP_TRACE_RB_PREPARE, &buffer->node);
- if (ret < 0)
- goto fail_free_buffers;
+ /* If already mapped, do not hook to CPU hotplug */
+ if (!start) {
+ ret = cpuhp_state_add_instance(CPUHP_TRACE_RB_PREPARE, &buffer->node);
+ if (ret < 0)
+ goto fail_free_buffers;
+ }
mutex_init(&buffer->mutex);
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index c01375adc471..1c69ca1f1088 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -3697,8 +3697,8 @@ static void test_can_verify(void)
void trace_check_vprintf(struct trace_iterator *iter, const char *fmt,
va_list ap)
{
- long text_delta = iter->tr->text_delta;
- long data_delta = iter->tr->data_delta;
+ long text_delta = 0;
+ long data_delta = 0;
const char *p = fmt;
const char *str;
bool good;
@@ -3710,6 +3710,17 @@ void trace_check_vprintf(struct trace_iterator *iter, const char *fmt,
if (static_branch_unlikely(&trace_no_verify))
goto print;
+ /*
+ * When the kernel is booted with the tp_printk command line
+ * parameter, trace events go directly through to printk().
+ * It also is checked by this function, but it does not
+ * have an associated trace_array (tr) for it.
+ */
+ if (iter->tr) {
+ text_delta = iter->tr->text_delta;
+ data_delta = iter->tr->data_delta;
+ }
+
/* Don't bother checking when doing a ftrace_dump() */
if (iter->fmt == static_fmt_buf)
goto print;
diff --git a/kernel/trace/trace_hwlat.c b/kernel/trace/trace_hwlat.c
index b791524a6536..3bd6071441ad 100644
--- a/kernel/trace/trace_hwlat.c
+++ b/kernel/trace/trace_hwlat.c
@@ -520,6 +520,8 @@ static void hwlat_hotplug_workfn(struct work_struct *dummy)
if (!hwlat_busy || hwlat_data.thread_mode != MODE_PER_CPU)
goto out_unlock;
+ if (!cpu_online(cpu))
+ goto out_unlock;
if (!cpumask_test_cpu(cpu, tr->tracing_cpumask))
goto out_unlock;
diff --git a/kernel/trace/trace_osnoise.c b/kernel/trace/trace_osnoise.c
index 1439064f65d6..a50ed23bee77 100644
--- a/kernel/trace/trace_osnoise.c
+++ b/kernel/trace/trace_osnoise.c
@@ -1953,12 +1953,8 @@ static void stop_kthread(unsigned int cpu)
{
struct task_struct *kthread;
- mutex_lock(&interface_lock);
- kthread = per_cpu(per_cpu_osnoise_var, cpu).kthread;
+ kthread = xchg_relaxed(&(per_cpu(per_cpu_osnoise_var, cpu).kthread), NULL);
if (kthread) {
- per_cpu(per_cpu_osnoise_var, cpu).kthread = NULL;
- mutex_unlock(&interface_lock);
-
if (cpumask_test_and_clear_cpu(cpu, &kthread_cpumask) &&
!WARN_ON(!test_bit(OSN_WORKLOAD, &osnoise_options))) {
kthread_stop(kthread);
@@ -1972,7 +1968,6 @@ static void stop_kthread(unsigned int cpu)
put_task_struct(kthread);
}
} else {
- mutex_unlock(&interface_lock);
/* if no workload, just return */
if (!test_bit(OSN_WORKLOAD, &osnoise_options)) {
/*
@@ -1994,8 +1989,12 @@ static void stop_per_cpu_kthreads(void)
{
int cpu;
- for_each_possible_cpu(cpu)
+ cpus_read_lock();
+
+ for_each_online_cpu(cpu)
stop_kthread(cpu);
+
+ cpus_read_unlock();
}
/*
@@ -2007,6 +2006,10 @@ static int start_kthread(unsigned int cpu)
void *main = osnoise_main;
char comm[24];
+ /* Do not start a new thread if it is already running */
+ if (per_cpu(per_cpu_osnoise_var, cpu).kthread)
+ return 0;
+
if (timerlat_enabled()) {
snprintf(comm, 24, "timerlat/%d", cpu);
main = timerlat_main;
@@ -2061,11 +2064,10 @@ static int start_per_cpu_kthreads(void)
if (cpumask_test_and_clear_cpu(cpu, &kthread_cpumask)) {
struct task_struct *kthread;
- kthread = per_cpu(per_cpu_osnoise_var, cpu).kthread;
+ kthread = xchg_relaxed(&(per_cpu(per_cpu_osnoise_var, cpu).kthread), NULL);
if (!WARN_ON(!kthread))
kthread_stop(kthread);
}
- per_cpu(per_cpu_osnoise_var, cpu).kthread = NULL;
}
for_each_cpu(cpu, current_mask) {
@@ -2095,6 +2097,8 @@ static void osnoise_hotplug_workfn(struct work_struct *dummy)
mutex_lock(&interface_lock);
cpus_read_lock();
+ if (!cpu_online(cpu))
+ goto out_unlock;
if (!cpumask_test_cpu(cpu, &osnoise_cpumask))
goto out_unlock;
generated by cgit v1.2.3 (git 2.39.1) at 2026-01-09 16:56:03 +0000