summaryrefslogtreecommitdiffstats
path: root/kernel/trace
diff options
context:
space:
mode:
authorSteven Rostedt <srostedt@redhat.com>2009-12-10 23:20:52 -0500
committerSteven Rostedt <rostedt@goodmis.org>2009-12-10 23:20:52 -0500
commitdd7f59435782a02ceb6d16b9ce823dd3345d75ec (patch)
treed85e0a7b2b587b41afd1c764e7c25b3fa2962613 /kernel/trace
parent184210154b9aa570099183f6c062ac4eb11190b7 (diff)
downloadlinux-dd7f59435782a02ceb6d16b9ce823dd3345d75ec.tar.bz2
ring-buffer: Move resize integrity check under reader lock
While using an application that does splice on the ftrace ring buffer at start up, I triggered an integrity check failure. Looking into this, I discovered that resizing the buffer performs an integrity check after the buffer is resized. This check unfortunately is preformed after it releases the reader lock. If a reader is reading the buffer it may cause the integrity check to trigger a false failure. This patch simply moves the integrity checker under the protection of the ring buffer reader lock. Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Diffstat (limited to 'kernel/trace')
-rw-r--r--kernel/trace/ring_buffer.c8
1 files changed, 4 insertions, 4 deletions
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 0d64c51ab4df..eccb4cf1e998 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -1208,9 +1208,9 @@ rb_remove_pages(struct ring_buffer_per_cpu *cpu_buffer, unsigned nr_pages)
return;
rb_reset_cpu(cpu_buffer);
- spin_unlock_irq(&cpu_buffer->reader_lock);
-
rb_check_pages(cpu_buffer);
+
+ spin_unlock_irq(&cpu_buffer->reader_lock);
}
static void
@@ -1233,9 +1233,9 @@ rb_insert_pages(struct ring_buffer_per_cpu *cpu_buffer,
list_add_tail(&bpage->list, cpu_buffer->pages);
}
rb_reset_cpu(cpu_buffer);
- spin_unlock_irq(&cpu_buffer->reader_lock);
-
rb_check_pages(cpu_buffer);
+
+ spin_unlock_irq(&cpu_buffer->reader_lock);
}
/**