这些.o是我编译内核时找到的，但不知道它们对应的源文件是哪个(百度GOOGLE了很久，找不到)
我用的内核是linux3.0.101
对应目录在：linux3.0.101/sound/
生成这个文件的makefile语句是：obj-$(CONFIG_SND_PCM) += snd-pcm.o snd-page-alloc.o
但该目录下没有snd-pcm.s或者snd-pcm.c之类的源文件
详见如下命令：
linux-3.0.101$ find -iname snd*|sort
./drivers/staging/go7007/snd-go7007.c
./include/config/snd
./include/config/snd.h
./include/sound/snd_wavefront.h
./sound/core/snd.o
./sound/core/snd-page-alloc.o
./sound/core/snd-pcm.o
./sound/core/snd-timer.o
./sound/ppc/snd_ps3.c
./sound/ppc/snd_ps3.h
./sound/ppc/snd_ps3_reg.h
./sound/soc/atmel/snd-soc-afeb9260.c
./sound/soc/codecs/snd-soc-mxc-hdmi.o
./sound/soc/codecs/snd-soc-mxc-spdif.o
./sound/soc/codecs/snd-soc-wm8962.o
./sound/soc/imx/snd-soc-imx-hdmi.o
./sound/soc/imx/snd-soc-imx-mx2.o
./sound/soc/imx/snd-soc-imx.o
./sound/soc/imx/snd-soc-imx-spdif-dai.o
./sound/soc/imx/snd-soc-imx-spdif.o
./sound/soc/imx/snd-soc-imx-wm8962.o
./sound/soc/snd-soc-core.o
希望大神们能提供下思路，谢谢！
