[ANNOUNCE] 4.19.106-rt45
From: Steven Rostedt
Date: Tue Mar 10 2020 - 13:32:00 EST
Dear RT Folks,
I'm pleased to announce the 4.19.106-rt45 stable release.
You can get this release via the git tree at:
git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-stable-rt.git
branch: v4.19-rt
Head SHA1: d515995ead09469fbddcb2ffff800caab9cb0c5f
Or to build 4.19.106-rt45 directly, the following patches should be applied:
http://www.kernel.org/pub/linux/kernel/v4.x/linux-4.19.tar.xz
http://www.kernel.org/pub/linux/kernel/v4.x/patch-4.19.106.xz
http://www.kernel.org/pub/linux/kernel/projects/rt/4.19/patch-4.19.106-rt45.patch.xz
You can also build from 4.19.106-rt44 by applying the incremental patch:
http://www.kernel.org/pub/linux/kernel/projects/rt/4.19/incr/patch-4.19.106-rt44-rt45.patch.xz
Enjoy,
-- Steve
Changes from v4.19.106-rt44:
---
Matt Fleming (1):
mm/memcontrol: Move misplaced local_unlock_irqrestore()
Scott Wood (2):
sched: migrate_enable: Use per-cpu cpu_stop_work
sched: migrate_enable: Remove __schedule() call
Sebastian Andrzej Siewior (4):
userfaultfd: Use a seqlock instead of seqcount
locallock: Include header for the `current' macro
drm/vmwgfx: Drop preempt_disable() in vmw_fifo_ping_host()
tracing: make preempt_lazy and migrate_disable counter smaller
Steven Rostedt (VMware) (1):
Linux 4.19.106-rt45
----
drivers/gpu/drm/vmwgfx/vmwgfx_fifo.c | 2 --
fs/userfaultfd.c | 12 ++++++------
include/linux/locallock.h | 1 +
include/linux/trace_events.h | 3 +--
kernel/sched/core.c | 23 ++++++++++++++---------
kernel/trace/trace_events.c | 4 ++--
localversion-rt | 2 +-
mm/memcontrol.c | 2 +-
8 files changed, 26 insertions(+), 23 deletions(-)
---------------------------
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_fifo.c b/drivers/gpu/drm/vmwgfx/vmwgfx_fifo.c
index d0fd147ef75f..fb5a3461bb8c 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_fifo.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_fifo.c
@@ -167,10 +167,8 @@ void vmw_fifo_ping_host(struct vmw_private *dev_priv, uint32_t reason)
{
u32 *fifo_mem = dev_priv->mmio_virt;
- preempt_disable();
if (cmpxchg(fifo_mem + SVGA_FIFO_BUSY, 0, 1) == 0)
vmw_write(dev_priv, SVGA_REG_SYNC, reason);
- preempt_enable();
}
void vmw_fifo_release(struct vmw_private *dev_priv, struct vmw_fifo_state *fifo)
diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c
index d269d1139f7f..ff6be687f68e 100644
--- a/fs/userfaultfd.c
+++ b/fs/userfaultfd.c
@@ -61,7 +61,7 @@ struct userfaultfd_ctx {
/* waitqueue head for events */
wait_queue_head_t event_wqh;
/* a refile sequence protected by fault_pending_wqh lock */
- struct seqcount refile_seq;
+ seqlock_t refile_seq;
/* pseudo fd refcounting */
atomic_t refcount;
/* userfaultfd syscall flags */
@@ -1064,7 +1064,7 @@ static ssize_t userfaultfd_ctx_read(struct userfaultfd_ctx *ctx, int no_wait,
* waitqueue could become empty if this is the
* only userfault.
*/
- write_seqcount_begin(&ctx->refile_seq);
+ write_seqlock(&ctx->refile_seq);
/*
* The fault_pending_wqh.lock prevents the uwq
@@ -1090,7 +1090,7 @@ static ssize_t userfaultfd_ctx_read(struct userfaultfd_ctx *ctx, int no_wait,
list_del(&uwq->wq.entry);
add_wait_queue(&ctx->fault_wqh, &uwq->wq);
- write_seqcount_end(&ctx->refile_seq);
+ write_sequnlock(&ctx->refile_seq);
/* careful to always initialize msg if ret == 0 */
*msg = uwq->msg;
@@ -1263,11 +1263,11 @@ static __always_inline void wake_userfault(struct userfaultfd_ctx *ctx,
* sure we've userfaults to wake.
*/
do {
- seq = read_seqcount_begin(&ctx->refile_seq);
+ seq = read_seqbegin(&ctx->refile_seq);
need_wakeup = waitqueue_active(&ctx->fault_pending_wqh) ||
waitqueue_active(&ctx->fault_wqh);
cond_resched();
- } while (read_seqcount_retry(&ctx->refile_seq, seq));
+ } while (read_seqretry(&ctx->refile_seq, seq));
if (need_wakeup)
__wake_userfault(ctx, range);
}
@@ -1938,7 +1938,7 @@ static void init_once_userfaultfd_ctx(void *mem)
init_waitqueue_head(&ctx->fault_wqh);
init_waitqueue_head(&ctx->event_wqh);
init_waitqueue_head(&ctx->fd_wqh);
- seqcount_init(&ctx->refile_seq);
+ seqlock_init(&ctx->refile_seq);
}
SYSCALL_DEFINE1(userfaultfd, int, flags)
diff --git a/include/linux/locallock.h b/include/linux/locallock.h
index 921eab83cd34..81c89d87723b 100644
--- a/include/linux/locallock.h
+++ b/include/linux/locallock.h
@@ -3,6 +3,7 @@
#include <linux/percpu.h>
#include <linux/spinlock.h>
+#include <asm/current.h>
#ifdef CONFIG_PREEMPT_RT_BASE
diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h
index 72864a11cec0..e26a85c1b7ba 100644
--- a/include/linux/trace_events.h
+++ b/include/linux/trace_events.h
@@ -62,8 +62,7 @@ struct trace_entry {
unsigned char flags;
unsigned char preempt_count;
int pid;
- unsigned short migrate_disable;
- unsigned short padding;
+ unsigned char migrate_disable;
unsigned char preempt_lazy_count;
};
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 4616c086dd26..02e51c74e0bf 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -7291,6 +7291,9 @@ static void migrate_disabled_sched(struct task_struct *p)
p->migrate_disable_scheduled = 1;
}
+static DEFINE_PER_CPU(struct cpu_stop_work, migrate_work);
+static DEFINE_PER_CPU(struct migration_arg, migrate_arg);
+
void migrate_enable(void)
{
struct task_struct *p = current;
@@ -7329,23 +7332,25 @@ void migrate_enable(void)
WARN_ON(smp_processor_id() != cpu);
if (!is_cpu_allowed(p, cpu)) {
- struct migration_arg arg = { .task = p };
- struct cpu_stop_work work;
+ struct migration_arg __percpu *arg;
+ struct cpu_stop_work __percpu *work;
struct rq_flags rf;
+ work = this_cpu_ptr(&migrate_work);
+ arg = this_cpu_ptr(&migrate_arg);
+ WARN_ON_ONCE(!arg->done && !work->disabled && work->arg);
+
+ arg->task = p;
+ arg->done = false;
+
rq = task_rq_lock(p, &rf);
update_rq_clock(rq);
- arg.dest_cpu = select_fallback_rq(cpu, p);
+ arg->dest_cpu = select_fallback_rq(cpu, p);
task_rq_unlock(rq, p, &rf);
stop_one_cpu_nowait(task_cpu(p), migration_cpu_stop,
- &arg, &work);
+ arg, work);
tlb_migrate_finish(p->mm);
- __schedule(true);
- if (!work.disabled) {
- while (!arg.done)
- cpu_relax();
- }
}
out:
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 1febb0ca4c81..07b8f5bfd263 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -188,8 +188,8 @@ static int trace_define_common_fields(void)
__common_field(unsigned char, flags);
__common_field(unsigned char, preempt_count);
__common_field(int, pid);
- __common_field(unsigned short, migrate_disable);
- __common_field(unsigned short, padding);
+ __common_field(unsigned char, migrate_disable);
+ __common_field(unsigned char, preempt_lazy_count);
return ret;
}
diff --git a/localversion-rt b/localversion-rt
index ac4d836a809d..38c40b21a885 100644
--- a/localversion-rt
+++ b/localversion-rt
@@ -1 +1 @@
--rt44
+-rt45
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 421ac74450f6..519528959eef 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -6540,10 +6540,10 @@ void mem_cgroup_swapout(struct page *page, swp_entry_t entry)
mem_cgroup_charge_statistics(memcg, page, PageTransHuge(page),
-nr_entries);
memcg_check_events(memcg, page);
+ local_unlock_irqrestore(event_lock, flags);
if (!mem_cgroup_is_root(memcg))
css_put_many(&memcg->css, nr_entries);
- local_unlock_irqrestore(event_lock, flags);
}
/**