On Thu, Mar 03, 2022 at 11:25:05PM +0100, Christian Melki wrote: > * xz needs crc32 instead of crc64 for the kernel cpio.
Good point. I didn't know about that. > * Set zstd compression level to the same as for the kernel (19). Makes sense. > * Use multithreading for zstd (deterministic, afaiu). It is. I looked into this because I was curious. And it makes sense. zstd was developed at a time when reproducibility was already important. > Actively decided against -T0 for xz, as compression > is not deterministic when number of threads varies. We definitively want to be reproducible here. > Signed-off-by: Christian Melki <[email protected]> > --- > rules/image-root-cpio.make | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/rules/image-root-cpio.make b/rules/image-root-cpio.make > index fdb0ccfff..eb09dd53e 100644 > --- a/rules/image-root-cpio.make > +++ b/rules/image-root-cpio.make > @@ -26,6 +26,9 @@ IMAGE_ROOT_CPIO_CONFIG := cpio.config > > IMAGE_ROOT_CPIO_ENV := \ > FORMAT="newc" \ > + ZSTD_CLEVEL="19" \ > + ZSTD_NBTHREADS="0" \ > + XZ_OPT="--check=crc32" \ > COMPRESS=$(call remove_quotes, > $(PTXCONF_IMAGE_ROOT_CPIO_COMPRESSION_UTIL)) Add the options to the PTXCONF_IMAGE_ROOT_CPIO_COMPRESSION_UTIL defaults and keep the quotes here: COMPRESS=$(PTXCONF_IMAGE_ROOT_CPIO_COMPRESSION_UTIL) genimage explicitly does not quote to make to possible to specify the compressor with options. At least I thinks that should work. And maybe we could add a IMAGE_ROOT_CPIO_COMPRESSION_MODE_CUSTOM and then add 'prompt "suffix" if IMAGE_ROOT_CPIO_COMPRESSION_MODE_CUSTOM' to the suffix and similar for the util. This way the user could tweak things if absolutely necessary. What do you think? Michael > > ifdef PTXCONF_IMAGE_ROOT_CPIO > -- > 2.30.2 > > > _______________________________________________ > ptxdist mailing list > [email protected] > To unsubscribe, send a mail with subject "unsubscribe" to > [email protected] > -- Pengutronix e.K. | | Steuerwalder Str. 21 | http://www.pengutronix.de/ | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 | _______________________________________________ ptxdist mailing list [email protected] To unsubscribe, send a mail with subject "unsubscribe" to [email protected]
