head_bit 1501 kernel/trace/ring_buffer.c unsigned long head_bit; head_bit 1504 kernel/trace/ring_buffer.c head_bit = 0; head_bit 1533 kernel/trace/ring_buffer.c head_bit |= (unsigned long)to_remove & RB_PAGE_HEAD; head_bit 1544 kernel/trace/ring_buffer.c head_bit); head_bit 1552 kernel/trace/ring_buffer.c if (head_bit)