diff options
Diffstat (limited to 'kernel/trace/ring_buffer.c')
| -rw-r--r-- | kernel/trace/ring_buffer.c | 25 |
1 files changed, 9 insertions, 16 deletions
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index a1ca4956ab5..0d64c51ab4d 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -1193,9 +1193,6 @@ rb_remove_pages(struct ring_buffer_per_cpu *cpu_buffer, unsigned nr_pages) struct list_head *p; unsigned i; - atomic_inc(&cpu_buffer->record_disabled); - synchronize_sched(); - spin_lock_irq(&cpu_buffer->reader_lock); rb_head_page_deactivate(cpu_buffer); @@ -1214,9 +1211,6 @@ rb_remove_pages(struct ring_buffer_per_cpu *cpu_buffer, unsigned nr_pages) spin_unlock_irq(&cpu_buffer->reader_lock); rb_check_pages(cpu_buffer); - - atomic_dec(&cpu_buffer->record_disabled); - } static void @@ -1227,9 +1221,6 @@ rb_insert_pages(struct ring_buffer_per_cpu *cpu_buffer, struct list_head *p; unsigned i; - atomic_inc(&cpu_buffer->record_disabled); - synchronize_sched(); - spin_lock_irq(&cpu_buffer->reader_lock); rb_head_page_deactivate(cpu_buffer); @@ -1245,8 +1236,6 @@ rb_insert_pages(struct ring_buffer_per_cpu *cpu_buffer, spin_unlock_irq(&cpu_buffer->reader_lock); rb_check_pages(cpu_buffer); - - atomic_dec(&cpu_buffer->record_disabled); } /** @@ -1254,11 +1243,6 @@ rb_insert_pages(struct ring_buffer_per_cpu *cpu_buffer, * @buffer: the buffer to resize. * @size: the new size. * - * The tracer is responsible for making sure that the buffer is - * not being used while changing the size. - * Note: We may be able to change the above requirement by using - * RCU synchronizations. - * * Minimum size is 2 * BUF_PAGE_SIZE. * * Returns -1 on failure. @@ -1290,6 +1274,11 @@ int ring_buffer_resize(struct ring_buffer *buffer, unsigned long size) if (size == buffer_size) return size; + atomic_inc(&buffer->record_disabled); + + /* Make sure all writers are done with this buffer. */ + synchronize_sched(); + mutex_lock(&buffer->mutex); get_online_cpus(); @@ -1352,6 +1341,8 @@ int ring_buffer_resize(struct ring_buffer *buffer, unsigned long size) put_online_cpus(); mutex_unlock(&buffer->mutex); + atomic_dec(&buffer->record_disabled); + return size; free_pages: @@ -1361,6 +1352,7 @@ int ring_buffer_resize(struct ring_buffer *buffer, unsigned long size) } put_online_cpus(); mutex_unlock(&buffer->mutex); + atomic_dec(&buffer->record_disabled); return -ENOMEM; /* @@ -1370,6 +1362,7 @@ int ring_buffer_resize(struct ring_buffer *buffer, unsigned long size) out_fail: put_online_cpus(); mutex_unlock(&buffer->mutex); + atomic_dec(&buffer->record_disabled); return -1; } EXPORT_SYMBOL_GPL(ring_buffer_resize); |