diff options
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/fork.c | 7 | ||||
| -rw-r--r-- | kernel/kfifo.c | 9 | ||||
| -rw-r--r-- | kernel/sched.c | 10 | ||||
| -rw-r--r-- | kernel/watchdog.c | 3 | ||||
| -rw-r--r-- | kernel/workqueue.c | 9 |
5 files changed, 35 insertions, 3 deletions
diff --git a/kernel/fork.c b/kernel/fork.c index 856eac3ec52..b7e9d60a675 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -300,7 +300,7 @@ out: #ifdef CONFIG_MMU static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm) { - struct vm_area_struct *mpnt, *tmp, **pprev; + struct vm_area_struct *mpnt, *tmp, *prev, **pprev; struct rb_node **rb_link, *rb_parent; int retval; unsigned long charge; @@ -328,6 +328,7 @@ static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm) if (retval) goto out; + prev = NULL; for (mpnt = oldmm->mmap; mpnt; mpnt = mpnt->vm_next) { struct file *file; @@ -359,7 +360,7 @@ static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm) goto fail_nomem_anon_vma_fork; tmp->vm_flags &= ~VM_LOCKED; tmp->vm_mm = mm; - tmp->vm_next = NULL; + tmp->vm_next = tmp->vm_prev = NULL; file = tmp->vm_file; if (file) { struct inode *inode = file->f_path.dentry->d_inode; @@ -392,6 +393,8 @@ static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm) */ *pprev = tmp; pprev = &tmp->vm_next; + tmp->vm_prev = prev; + prev = tmp; __vma_link_rb(mm, tmp, rb_link, rb_parent); rb_link = &tmp->vm_rb.rb_right; diff --git a/kernel/kfifo.c b/kernel/kfifo.c index 4502604ecad..6b5580c5764 100644 --- a/kernel/kfifo.c +++ b/kernel/kfifo.c @@ -503,6 +503,15 @@ unsigned int __kfifo_out_r(struct __kfifo *fifo, void *buf, } EXPORT_SYMBOL(__kfifo_out_r); +void __kfifo_skip_r(struct __kfifo *fifo, size_t recsize) +{ + unsigned int n; + + n = __kfifo_peek_n(fifo, recsize); + fifo->out += n + recsize; +} +EXPORT_SYMBOL(__kfifo_skip_r); + int __kfifo_from_user_r(struct __kfifo *fifo, const void __user *from, unsigned long len, unsigned int *copied, size_t recsize) { diff --git a/kernel/sched.c b/kernel/sched.c index 41541d79e3c..09b574e7f4d 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -3865,8 +3865,16 @@ int mutex_spin_on_owner(struct mutex *lock, struct thread_info *owner) /* * Owner changed, break to re-assess state. */ - if (lock->owner != owner) + if (lock->owner != owner) { + /* + * If the lock has switched to a different owner, + * we likely have heavy contention. Return 0 to quit + * optimistic spinning and not contend further: + */ + if (lock->owner) + return 0; break; + } /* * Is that owner really running on that cpu? diff --git a/kernel/watchdog.c b/kernel/watchdog.c index 613bc1f0461..0d53c8e853b 100644 --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -206,6 +206,9 @@ void watchdog_overflow_callback(struct perf_event *event, int nmi, struct perf_sample_data *data, struct pt_regs *regs) { + /* Ensure the watchdog never gets throttled */ + event->hw.interrupts = 0; + if (__get_cpu_var(watchdog_nmi_touch) == true) { __get_cpu_var(watchdog_nmi_touch) = false; return; diff --git a/kernel/workqueue.c b/kernel/workqueue.c index 2994a0e3a61..8bd600c020e 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -35,6 +35,9 @@ #include <linux/lockdep.h> #include <linux/idr.h> +#define CREATE_TRACE_POINTS +#include <trace/events/workqueue.h> + #include "workqueue_sched.h" enum { @@ -1790,7 +1793,13 @@ static void process_one_work(struct worker *worker, struct work_struct *work) work_clear_pending(work); lock_map_acquire(&cwq->wq->lockdep_map); lock_map_acquire(&lockdep_map); + trace_workqueue_execute_start(work); f(work); + /* + * While we must be careful to not use "work" after this, the trace + * point will only record its address. + */ + trace_workqueue_execute_end(work); lock_map_release(&lockdep_map); lock_map_release(&cwq->wq->lockdep_map); |