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authorRandy Dunlap <randy.dunlap@oracle.com>2008-04-25 16:38:44 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2008-04-25 18:24:20 -0700
commit753d7054c318f323a7c135c71c68171a6b6a88fc (patch)
treef32efb19dc9b447eb488ec620c51546e140a0b9f /Documentation
parent3dd7b71ca0f7ff8410a6b8cb15e5f670f90181e4 (diff)
downloadlinux-stericsson-753d7054c318f323a7c135c71c68171a6b6a88fc.tar.gz
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 It is outdated and has been (functionally) replaced by Documentation/kbuild/*.txt.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 <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/00-INDEX2
-rw-r--r--Documentation/smart-config.txt98
2 files changed, 0 insertions, 100 deletions
diff --git a/Documentation/00-INDEX b/Documentation/00-INDEX
index a82a113b4a4b..1977fab38656 100644
--- a/Documentation/00-INDEX
+++ b/Documentation/00-INDEX
@@ -329,8 +329,6 @@ sgi-visws.txt
- short blurb on the SGI Visual Workstations.
sh/
- directory with info on porting Linux to a new architecture.
-smart-config.txt
- - description of the Smart Config makefile feature.
sound/
- directory with info on sound card support.
sparc/
diff --git a/Documentation/smart-config.txt b/Documentation/smart-config.txt
deleted file mode 100644
index 8467447b5a87..000000000000
--- a/Documentation/smart-config.txt
+++ /dev/null
@@ -1,98 +0,0 @@
-Smart CONFIG_* Dependencies
-1 August 1999
-
-Michael Chastain <mec@shout.net>
-Werner Almesberger <almesber@lrc.di.epfl.ch>
-Martin von Loewis <martin@mira.isdn.cs.tu-berlin.de>
-
-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 */
- #else
- /* Manual frobbing only */
- #endif
-
- ...
-
- #ifdef CONFIG_FOO_MODEL_TWO
- /* Code for model two */
- #endif
-
- 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- to be out of date, which will cause drivers/net/foo.c to be recompiled.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 \
- include/config/foo/model/two.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.
-
-Flag Dependencies
-
- 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).
-
-Per-source-file Flags
-
- 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.
-
-Credit
-
- 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.