lockdep: Reduce stack_trace usage

[safe/jmp/linux-2.6] / kernel / relay.c

diff --git a/kernel/relay.c b/kernel/relay.c
index 9d79b78..3d97f28 100644 (file)
--- a/kernel/relay.c
+++ b/kernel/relay.c
@@ -60,7 +60,7 @@ static int relay_buf_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
 /*
  * vm_ops for relay file mappings.
  */
-static struct vm_operations_struct relay_file_mmap_ops = {
+static const struct vm_operations_struct relay_file_mmap_ops = {
        .fault = relay_buf_fault,
        .close = relay_file_mmap_close,
 };
@@ -677,9 +677,7 @@ int relay_late_setup_files(struct rchan *chan,
         */
        for_each_online_cpu(i) {
                if (unlikely(!chan->buf[i])) {
-                       printk(KERN_ERR "relay_late_setup_files: CPU %u "
-                                       "has no buffer, it must have!\n", i);
-                       BUG();
+                       WARN_ONCE(1, KERN_ERR "CPU has no buffer!\n");
                        err = -EINVAL;
                        break;
                }
@@ -750,7 +748,7 @@ size_t relay_switch_subbuf(struct rchan_buf *buf, size_t length)
                         * from the scheduler (trying to re-grab
                         * rq->lock), so defer it.
                         */
-                       __mod_timer(&buf->timer, jiffies + 1);
+                       mod_timer(&buf->timer, jiffies + 1);
        }
 
        old = buf->data;
@@ -797,13 +795,15 @@ void relay_subbufs_consumed(struct rchan *chan,
        if (!chan)
                return;
 
-       if (cpu >= NR_CPUS || !chan->buf[cpu])
+       if (cpu >= NR_CPUS || !chan->buf[cpu] ||
+                                       subbufs_consumed > chan->n_subbufs)
                return;
 
        buf = chan->buf[cpu];
-       buf->subbufs_consumed += subbufs_consumed;
-       if (buf->subbufs_consumed > buf->subbufs_produced)
+       if (subbufs_consumed > buf->subbufs_produced - buf->subbufs_consumed)
                buf->subbufs_consumed = buf->subbufs_produced;
+       else
+               buf->subbufs_consumed += subbufs_consumed;
 }
 EXPORT_SYMBOL_GPL(relay_subbufs_consumed);
 
@@ -1198,7 +1198,7 @@ static void relay_pipe_buf_release(struct pipe_inode_info *pipe,
        relay_consume_bytes(rbuf, buf->private);
 }
 
-static struct pipe_buf_operations relay_pipe_buf_ops = {
+static const struct pipe_buf_operations relay_pipe_buf_ops = {
        .can_merge = 0,
        .map = generic_pipe_buf_map,
        .unmap = generic_pipe_buf_unmap,
@@ -1215,14 +1215,14 @@ static void relay_page_release(struct splice_pipe_desc *spd, unsigned int i)
 /*
  *     subbuf_splice_actor - splice up to one subbuf's worth of data
  */
-static int subbuf_splice_actor(struct file *in,
+static ssize_t subbuf_splice_actor(struct file *in,
                               loff_t *ppos,
                               struct pipe_inode_info *pipe,
                               size_t len,
                               unsigned int flags,
                               int *nonpad_ret)
 {
-       unsigned int pidx, poff, total_len, subbuf_pages, nr_pages, ret;
+       unsigned int pidx, poff, total_len, subbuf_pages, nr_pages;
        struct rchan_buf *rbuf = in->private_data;
        unsigned int subbuf_size = rbuf->chan->subbuf_size;
        uint64_t pos = (uint64_t) *ppos;
@@ -1241,6 +1241,7 @@ static int subbuf_splice_actor(struct file *in,
                .ops = &relay_pipe_buf_ops,
                .spd_release = relay_page_release,
        };
+       ssize_t ret;
 
        if (rbuf->subbufs_produced == rbuf->subbufs_consumed)
                return 0;