Messages in this thread | | | Date | Wed, 1 Oct 2014 20:15:33 +0200 | From | Nicholas Mc Guire <> | Subject | Re: [PATCH 1/3] handling of _shipped files |
| |
On Wed, 01 Oct 2014, Randy Dunlap wrote:
> On 10/01/14 06:36, Nicholas Mc Guire wrote: > > > > handling of _shipped files > > > > This adds a section on handling of _shipped files in kbuild > > Makefiles and the build process. > > > > Signed-off-by: Nicholas Mc Guire <der.herr@hofr.at> > > --- > > Documentation/kbuild/makefiles.txt | 57 +++++++++++++++++++++++++++++++++++- > > 1 file changed, 56 insertions(+), 1 deletion(-) > > > > diff --git a/Documentation/kbuild/makefiles.txt b/Documentation/kbuild/makefiles.txt > > index 764f599..d0bd91a 100644 > > --- a/Documentation/kbuild/makefiles.txt > > +++ b/Documentation/kbuild/makefiles.txt > > @@ -19,6 +19,7 @@ This document describes the Linux kernel Makefiles. > > --- 3.10 Special Rules > > --- 3.11 $(CC) support functions > > --- 3.12 $(LD) support functions > > + --- 3.13 _shipped - generated files > > > > === 4 Host Program support > > --- 4.1 Simple Host Program > > @@ -595,6 +596,60 @@ more details, with real examples. > > LDFLAGS_vmlinux += $(call ld-option, -X) > > > > > > +--- 3.13 _shipped - generated files > > + > > + Some sources in the kernel are generated by tools or special > > + purpose scrips so that the build process dependencies can be kept > > scripts > > > + at a resonable level. Also in cases where the translation is not > > reasonable > > > + configuration dependent but might impact build time _shipped files > > build time, > > > + may be added along with the actual sources to speed up the build > > + process. > > + > > + For standard tools like lex and yacc the make process will actually > > + generate the _shipped files (see scripts/Makefile.lib) and retain > > + them by marking them .PRECIOUS so they are not removed by the clean > > + targets. > > + > > + For non standard tools the generation of the _shipped file it self > > non-standard itself > > > + may be manually achived by building and then renaming. A makefile > > achieved > > > + target for generate the actual target file should to be provided > > to generate > > > + though and can be conditioned on an environment variable. > > Most examples that I see just expect the Makefile to be modified to set > (or define) the variable. >
Yes - but is that the prefered way of doing it ? I guess it would be more clear to have a variable that is taken from the environment and not via .config to trigger a conditional rebuild as the defkeymap example does it.
> > + > > + Example: > > + ifdef GENERATE_KEYMAP > > + > > + $(obj)/defkeymap.c: $(obj)/%.c: $(src)/%.map > > + loadkeys --mktable $< > $@ > > + > > + endif > > + > > + The _shipped file does not appear in the actual Makefile, this is > > + handled by the rules found in scripts/Makefile.lib. > > + > > + <snip> > > + cmd_shipped = cat $< > $@ > > + > > + $(obj)/%: $(src)/%_shipped > > + $(call cmd,shipped) > > + <snip> > > + > > + which simply will copy the target_shipped to the target > > + > > + If a file of a make target is found in the build directory with the > > + extension _shipped make will used it, rather than generating the > > _shipped, make will use it rather than generating the > > > + respective target file from source. > > + > > + The build will indicate the use of the _shipped file by the SHIPPED > > + quiet command in the make output. > > + > > + Example: > > + LD drivers/scsi/aic7xxx/built-in.o > > + SHIPPED drivers/scsi/aic7xxx/aic79xx_seq.h > > + SHIPPED drivers/scsi/aic7xxx/aic79xx_reg.h > > + CC [M] drivers/scsi/aic7xxx/aic79xx_core.o > > + CC [M] drivers/scsi/aic7xxx/aic79xx_pci.o > > + SHIPPED drivers/scsi/aic7xxx/aic79xx_reg_print.c > > + CC [M] drivers/scsi/aic7xxx/aic79xx_reg_print.o > > === 4 Host Program support > > > > Kbuild supports building executables on the host for use during the > > @@ -1423,10 +1478,10 @@ Original version made by Michael Elizabeth Chastain, <mailto:mec@shout.net> > > Updates by Kai Germaschewski <kai@tp1.ruhr-uni-bochum.de> > > Updates by Sam Ravnborg <sam@ravnborg.org> > > Language QA by Jan Engelhardt <jengelh@gmx.de> > > +Kbuild support for shipped files Nicholas Mc Guire <der.herr@hofr.at> > > > > === 11 TODO > > > > -- Describe how kbuild supports shipped files with _shipped. > > - Generating offset header files. > > - Add more variables to section 7? > > > > > and thanks for the language fixes - thought I had spellchecked it but obviously I did not
thx! hofrat
| |