|author||Randy Dunlap <firstname.lastname@example.org>||2008-04-25 16:38:44 -0700|
|committer||Linus Torvalds <email@example.com>||2008-04-25 18:24:20 -0700|
documentation: remove smart-config.txt
As requested by Sam Ravnborg: Remove Documentation/smart-config.txt. It is outdated and has been (functionally) replaced by Documentation/kbuild/*.txt. Signed-off-by: Randy Dunlap <firstname.lastname@example.org> Signed-off-by: Linus Torvalds <email@example.com>
Diffstat (limited to 'Documentation')
2 files changed, 0 insertions, 100 deletions
diff --git a/Documentation/00-INDEX b/Documentation/00-INDEX
index a82a113b4a4b..1977fab38656 100644
@@ -329,8 +329,6 @@ sgi-visws.txt
- short blurb on the SGI Visual Workstations.
- directory with info on porting Linux to a new architecture.
- - description of the Smart Config makefile feature.
- directory with info on sound card support.
diff --git a/Documentation/smart-config.txt b/Documentation/smart-config.txt
deleted file mode 100644
@@ -1,98 +0,0 @@
-Smart CONFIG_* Dependencies
-1 August 1999
-Michael Chastain <firstname.lastname@example.org>
-Werner Almesberger <email@example.com>
-Martin von Loewis <firstname.lastname@example.org>
-Here is the problem:
- Suppose that drivers/net/foo.c has the following lines:
- #include <linux/config.h>
- #ifdef CONFIG_FOO_AUTOFROB
- /* Code for auto-frobbing */
- /* Manual frobbing only */
- #ifdef CONFIG_FOO_MODEL_TWO
- /* Code for model two */
- Now suppose the user (the person building kernels) reconfigures the
- kernel to change some unrelated setting. This will regenerate the
- file include/linux/autoconf.h, which will cause include/linux/config.h
- to be out of date, which will cause drivers/net/foo.c to be recompiled.
- Most kernel sources, perhaps 80% of them, have at least one CONFIG_*
- dependency somewhere. So changing _any_ CONFIG_* setting requires
- almost _all_ of the kernel to be recompiled.
-Here is the solution:
- We've made the dependency generator, mkdep.c, smarter. Instead of
- generating this dependency:
- drivers/net/foo.c: include/linux/config.h
- It now generates these dependencies:
- drivers/net/foo.c: \
- include/config/foo/autofrob.h \
- So drivers/net/foo.c depends only on the CONFIG_* lines that
- it actually uses.
- A new program, split-include.c, runs at the beginning of
- compilation (make bzImage or make zImage). split-include reads
- include/linux/autoconf.h and updates the include/config/ tree,
- writing one file per option. It updates only the files for options
- that have changed.
- Martin Von Loewis contributed another feature to this patch:
- 'flag dependencies'. The idea is that a .o file depends on
- the compilation flags used to build it. The file foo.o has
- its flags stored in .flags.foo.o.
- Suppose the user changes the foo driver from resident to modular.
- 'make' will notice that the current foo.o was not compiled with
- -DMODULE and will recompile foo.c.
- All .o files made from C source have flag dependencies. So do .o
- files made with ld, and .a files made with ar. However, .o files
- made from assembly source do not have flag dependencies (nobody
- needs this yet, but it would be good to fix).
- Flag dependencies also work with per-source-file flags.
- You can specify compilation flags for individual source files
- like this:
- CFLAGS_foo.o = -DSPECIAL_FOO_DEFINE
- This helps clean up drivers/net/Makefile, drivers/scsi/Makefile,
- and several other Makefiles.
- Werner Almesberger had the original idea and wrote the first
- version of this patch.
- Michael Chastain picked it up and continued development. He is
- now the principal author and maintainer. Please report any bugs
- to him.
- Martin von Loewis wrote flag dependencies, with some modifications
- by Michael Chastain.
- Thanks to all of the beta testers.