make linux kernel tag files directory
$ mkdir linux_kernel_tagfiles # any name
$ cd linux_kernel_tagfiles/
$ export LINUX_TAGS_DIR=$PWD
make kernel version directory
$ mkdir v4.15 # any version
make linux kernel tag files and copy it to LINUX_TAGS_DIR
$ cd linux.git
$ gtags -v
$ cp -a G* $LINUX_TAGS_DIR/v4.15/
Usage: ling [global-options...] [version=<kernel_version>]
$ uname -r
5.0.0-stock
$ ling -x set_normalized_timespec
set_normalized_timespec 403 kernel/time/time.c void set_normalized_timespec(struct timespec *ts, time_t sec, s64 nsec)
$ ling -x set_normalized_timespec version=5.0
set_normalized_timespec 403 kernel/time/time.c void set_normalized_timespec(struct timespec *ts, time_t sec, s64 nsec)
$ ling -x set_normalized_timespec version=4.15
set_normalized_timespec 31 include/linux/time32.h # define set_normalized_timespec set_normalized_timespec64
set_normalized_timespec 425 kernel/time/time.c void set_normalized_timespec(struct timespec *ts, time_t sec, s64 nsec)