Commit 5d76065 moved the creation of the symvers directory to
include/kernel-build.mk. This is fine when building from scratch. But
when unpacking an SDK the directory doesn't exist and because the kernel
won't be built (again) this directory will not be created by the build
system, causing build failure if make tries to copy files into it.
This moves the creation of the symvers directory back into
include/kernel.mk so that the directory is created in any case.
Signed-off-by: Sebastian Kemper <sebastian_ml@gmx.net>
Define wildcard patterns for filtering in target/linux/generic/config-filter
Preparation for supporting newer kernels
Signed-off-by: Felix Fietkau <nbd@nbd.name>
This replaces the previous (deprecated) method of collecting symvers data
in $(PKG_BUILD_DIR)/Module.symvers, which does not work on newer kernels
Signed-off-by: Felix Fietkau <nbd@nbd.name>
zstd with its default settings (compression level -3) compresses better
than bzip2 -9 (which is the default setting), and is an order of magnitude
faster.
I made the following measurements for the most common compression tools
(all standard Debian Buster versions, default flags unless noted
otherwise), using the debug information of a large x86-64 kernel with
ALL_KMODS:
* kernel-debug.tar: 376M
* kernel-debug.tar.gz: 101M, compressed in ~12s
* kernel-debug.tar.bz2: 91M, compressed in ~15s
* kernel-debug.tar.xz: 57M, compressed in ~101s
* kernel-debug.tar.zst: 86M, compressed in ~1s
With zstd, there is still some room for improvement by increasing the
compression, but the slight increase in compression ratio
(22.83% -> 19.46%) does not justify the significant increase in
compression time (about 5 times on my machine) in my opinion.
Note that multithreaded compression (-T argument) does not affect
reproducibility with zstd.
Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
