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authorTakashi Iwai <tiwai@suse.de>2017-11-01 17:43:20 +0100
committerTakashi Iwai <tiwai@suse.de>2017-11-01 17:43:20 +0100
commita53a0ab8ff725672fcb47bb9a5ef75fce45679d0 (patch)
tree75cdea78f27fdd569d72cea0b7837bbcc8d871f7 /kernel/sched/membarrier.c
parent1f20f9ff57ca23b9f5502fca85ce3977e8496cb1 (diff)
parentb817d936248b9bcee8282e97fb1dda1b03c903fe (diff)
downloadlinux-a53a0ab8ff725672fcb47bb9a5ef75fce45679d0.tar.bz2
Merge tag 'asoc-fix-v4.14-rc7' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/sound into for-linus
ASoC: Fixes for v4.14 A bunch of fixes here, mostly device specific ones (the biggest one being the revert of the hotword support for rt5514), with a couple of core fixes for potential issues with corrupted or otherwise invalid topology files.
Diffstat (limited to 'kernel/sched/membarrier.c')
-rw-r--r--kernel/sched/membarrier.c34
1 files changed, 30 insertions, 4 deletions
diff --git a/kernel/sched/membarrier.c b/kernel/sched/membarrier.c
index a92fddc22747..dd7908743dab 100644
--- a/kernel/sched/membarrier.c
+++ b/kernel/sched/membarrier.c
@@ -18,6 +18,7 @@
#include <linux/membarrier.h>
#include <linux/tick.h>
#include <linux/cpumask.h>
+#include <linux/atomic.h>
#include "sched.h" /* for cpu_rq(). */
@@ -26,21 +27,26 @@
* except MEMBARRIER_CMD_QUERY.
*/
#define MEMBARRIER_CMD_BITMASK \
- (MEMBARRIER_CMD_SHARED | MEMBARRIER_CMD_PRIVATE_EXPEDITED)
+ (MEMBARRIER_CMD_SHARED | MEMBARRIER_CMD_PRIVATE_EXPEDITED \
+ | MEMBARRIER_CMD_REGISTER_PRIVATE_EXPEDITED)
static void ipi_mb(void *info)
{
smp_mb(); /* IPIs should be serializing but paranoid. */
}
-static void membarrier_private_expedited(void)
+static int membarrier_private_expedited(void)
{
int cpu;
bool fallback = false;
cpumask_var_t tmpmask;
+ if (!(atomic_read(&current->mm->membarrier_state)
+ & MEMBARRIER_STATE_PRIVATE_EXPEDITED_READY))
+ return -EPERM;
+
if (num_online_cpus() == 1)
- return;
+ return 0;
/*
* Matches memory barriers around rq->curr modification in
@@ -94,6 +100,24 @@ static void membarrier_private_expedited(void)
* rq->curr modification in scheduler.
*/
smp_mb(); /* exit from system call is not a mb */
+ return 0;
+}
+
+static void membarrier_register_private_expedited(void)
+{
+ struct task_struct *p = current;
+ struct mm_struct *mm = p->mm;
+
+ /*
+ * We need to consider threads belonging to different thread
+ * groups, which use the same mm. (CLONE_VM but not
+ * CLONE_THREAD).
+ */
+ if (atomic_read(&mm->membarrier_state)
+ & MEMBARRIER_STATE_PRIVATE_EXPEDITED_READY)
+ return;
+ atomic_or(MEMBARRIER_STATE_PRIVATE_EXPEDITED_READY,
+ &mm->membarrier_state);
}
/**
@@ -144,7 +168,9 @@ SYSCALL_DEFINE2(membarrier, int, cmd, int, flags)
synchronize_sched();
return 0;
case MEMBARRIER_CMD_PRIVATE_EXPEDITED:
- membarrier_private_expedited();
+ return membarrier_private_expedited();
+ case MEMBARRIER_CMD_REGISTER_PRIVATE_EXPEDITED:
+ membarrier_register_private_expedited();
return 0;
default:
return -EINVAL;