Dear RT folks!
I'm pleased to announce the v5.14-rt16 patch set.
Changes since v5.14-rt15:
- The scheduler related "balance_push()" fix in the previous release
had a logic error which has been now corrected. Patch by Thomas
Gleixner.
- The kcov related warning, reported by Clark Williams, has been
addressed.
Known issues
- netconsole triggers WARN.
- The "Memory controller" (CONFIG_MEMCG) has been disabled.
- A RCU and ARM64 warning has been fixed by Valentin Schneider. It is
still not clear if the RCU related change is correct.
- Clark Williams reported issues in i915 (execlists_dequeue_irq())
- Valentin Schneider reported a few splats on ARM64, see
https://https://lkml.kernel.org/r/.kernel.org/lkml/20210810134127.1394269-1-valentin.schneider@xxxxxxx/
The delta patch against v5.14-rt15 is appended below and can be found here:
https://cdn.kernel.org/pub/linux/kernel/projects/rt/5.14/incr/patch-5.14-rt15-rt16.patch.xz
You can get this release via the git tree at:
git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git v5.14-rt16
The RT patch against v5.14 can be found here:
https://cdn.kernel.org/pub/linux/kernel/projects/rt/5.14/older/patch-5.14-rt16.patch.xz
The split quilt queue is available at:
https://cdn.kernel.org/pub/linux/kernel/projects/rt/5.14/older/patches-5.14-rt16.tar.xz
Sebastian
diff --git a/Documentation/dev-tools/kcov.rst b/Documentation/dev-tools/kcov.rst
index d2c4c27e1702d..d83c9ab494275 100644
--- a/Documentation/dev-tools/kcov.rst
+++ b/Documentation/dev-tools/kcov.rst
@@ -50,6 +50,7 @@ The following program demonstrates coverage collection from within a test
#include <sys/mman.h>
#include <unistd.h>
#include <fcntl.h>
+ #include <linux/types.h>
#define KCOV_INIT_TRACE _IOR('c', 1, unsigned long)
#define KCOV_ENABLE _IO('c', 100)
@@ -177,6 +178,8 @@ Comparison operands collection
/* Read number of comparisons collected. */
n = __atomic_load_n(&cover[0], __ATOMIC_RELAXED);
for (i = 0; i < n; i++) {
+ uint64_t ip;
+
type = cover[i * KCOV_WORDS_PER_CMP + 1];
/* arg1 and arg2 - operands of the comparison. */
arg1 = cover[i * KCOV_WORDS_PER_CMP + 2];
@@ -251,6 +254,8 @@ selectively from different subsystems.
.. code-block:: c
+ /* Same includes and defines as above. */
+
struct kcov_remote_arg {
__u32 trace_mode;
__u32 area_size;
diff --git a/kernel/kcov.c b/kernel/kcov.c
index 80bfe71bbe13e..36ca640c4f8e7 100644
--- a/kernel/kcov.c
+++ b/kernel/kcov.c
@@ -88,6 +88,7 @@ static struct list_head kcov_remote_areas = LIST_HEAD_INIT(kcov_remote_areas);
struct kcov_percpu_data {
void *irq_area;
+ local_lock_t lock;
unsigned int saved_mode;
unsigned int saved_size;
@@ -96,7 +97,9 @@ struct kcov_percpu_data {
int saved_sequence;
};
-static DEFINE_PER_CPU(struct kcov_percpu_data, kcov_percpu_data);
+static DEFINE_PER_CPU(struct kcov_percpu_data, kcov_percpu_data) = {
+ .lock = INIT_LOCAL_LOCK(lock),
+};
/* Must be called with kcov_remote_lock locked. */
static struct kcov_remote *kcov_remote_find(u64 handle)
@@ -824,7 +827,7 @@ void kcov_remote_start(u64 handle)
if (!in_task() && !in_serving_softirq())
return;
- local_irq_save(flags);
+ local_lock_irqsave(&kcov_percpu_data.lock, flags);
/*
* Check that kcov_remote_start() is not called twice in background
@@ -832,7 +835,7 @@ void kcov_remote_start(u64 handle)
*/
mode = READ_ONCE(t->kcov_mode);
if (WARN_ON(in_task() && kcov_mode_enabled(mode))) {
- local_irq_restore(flags);
+ local_unlock_irqrestore(&kcov_percpu_data.lock, flags);
return;
}
/*
@@ -841,14 +844,15 @@ void kcov_remote_start(u64 handle)
* happened while collecting coverage from a background thread.
*/
if (WARN_ON(in_serving_softirq() && t->kcov_softirq)) {
- local_irq_restore(flags);
+ local_unlock_irqrestore(&kcov_percpu_data.lock, flags);
return;
}
spin_lock(&kcov_remote_lock);
remote = kcov_remote_find(handle);
if (!remote) {
- spin_unlock_irqrestore(&kcov_remote_lock, flags);
+ spin_unlock(&kcov_remote_lock);
+ local_unlock_irqrestore(&kcov_percpu_data.lock, flags);
return;
}
kcov_debug("handle = %llx, context: %s\n", handle,
@@ -869,19 +873,19 @@ void kcov_remote_start(u64 handle)
size = CONFIG_KCOV_IRQ_AREA_SIZE;
area = this_cpu_ptr(&kcov_percpu_data)->irq_area;
}
- spin_unlock_irqrestore(&kcov_remote_lock, flags);
+ spin_unlock(&kcov_remote_lock);
/* Can only happen when in_task(). */
if (!area) {
+ local_unlock_irqrestore(&kcov_percpu_data.lock, flags);
area = vmalloc(size * sizeof(unsigned long));
if (!area) {
kcov_put(kcov);
return;
}
+ local_lock_irqsave(&kcov_percpu_data.lock, flags);
}
- local_irq_save(flags);
-
/* Reset coverage size. */
*(u64 *)area = 0;
@@ -891,7 +895,7 @@ void kcov_remote_start(u64 handle)
}
kcov_start(t, kcov, size, area, mode, sequence);
- local_irq_restore(flags);
+ local_unlock_irqrestore(&kcov_percpu_data.lock, flags);
}
EXPORT_SYMBOL(kcov_remote_start);
@@ -965,12 +969,12 @@ void kcov_remote_stop(void)
if (!in_task() && !in_serving_softirq())
return;
- local_irq_save(flags);
+ local_lock_irqsave(&kcov_percpu_data.lock, flags);
mode = READ_ONCE(t->kcov_mode);
barrier();
if (!kcov_mode_enabled(mode)) {
- local_irq_restore(flags);
+ local_unlock_irqrestore(&kcov_percpu_data.lock, flags);
return;
}
/*
@@ -978,12 +982,12 @@ void kcov_remote_stop(void)
* actually found the remote handle and started collecting coverage.
*/
if (in_serving_softirq() && !t->kcov_softirq) {
- local_irq_restore(flags);
+ local_unlock_irqrestore(&kcov_percpu_data.lock, flags);
return;
}
/* Make sure that kcov_softirq is only set when in softirq. */
if (WARN_ON(!in_serving_softirq() && t->kcov_softirq)) {
- local_irq_restore(flags);
+ local_unlock_irqrestore(&kcov_percpu_data.lock, flags);
return;
}
@@ -1013,7 +1017,7 @@ void kcov_remote_stop(void)
spin_unlock(&kcov_remote_lock);
}
- local_irq_restore(flags);
+ local_unlock_irqrestore(&kcov_percpu_data.lock, flags);
/* Get in kcov_remote_start(). */
kcov_put(kcov);
@@ -1034,8 +1038,8 @@ static int __init kcov_init(void)
int cpu;
for_each_possible_cpu(cpu) {
- void *area = vmalloc(CONFIG_KCOV_IRQ_AREA_SIZE *
- sizeof(unsigned long));
+ void *area = vmalloc_node(CONFIG_KCOV_IRQ_AREA_SIZE *
+ sizeof(unsigned long), cpu_to_node(cpu));
if (!area)
return -ENOMEM;
per_cpu_ptr(&kcov_percpu_data, cpu)->irq_area = area;
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 7ce1935e74540..bb115218bb78b 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -8686,7 +8686,7 @@ static void balance_push(struct rq *rq)
* Only active while going offline and when invoked on the outgoing
* CPU.
*/
- if (!cpu_dying(rq->cpu) && rq == this_rq())
+ if (!cpu_dying(rq->cpu) || rq != this_rq())
return;
/*
diff --git a/localversion-rt b/localversion-rt
index 18777ec0c27d4..1199ebade17b4 100644
--- a/localversion-rt
+++ b/localversion-rt
@@ -1 +1 @@
--rt15
+-rt16
