We currently check the atomic headers at build-time to ensure they
haven't been modified directly, and these checks require regenerating
the headers in full. As this takes a few seconds, even when
parallelized, this is too slow to run for every kernel build.
Instead, we can generate a hash of each header as we generate them,
which we can cheaply check at build time (~0.16s for all headers).
This patch does so, updating headers with their hashes using the new
gen-atomics.sh script. As some users apparently build the kernel wihout
coreutils, lacking sha1sum, the checks are skipped in this case.
Presumably, most developers have a working coreutils installation.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: anders.roxell@linaro.org
Cc: linux-kernel@vger.kernel.rg
Cc: naresh.kamboju@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
As a step to ensuring the atomic* APIs are consistent, switch to fallbacks
generated by gen-atomic-fallback.sh.
These are checked in rather than generated with Kbuild, since:
* This allows inspection of the atomics with git grep and ctags on a
pristine tree, which Linus strongly prefers being able to do.
* The fallbacks are not affected by machine details or configuration
options, so it is not necessary to regenerate them to take these into
account.
* These are included by files required *very* early in the build process
(e.g. for generating bounds.h), and we'd rather not complicate the
top-level Kbuild file with dependencies.
The new fallback header should be equivalent to the old fallbacks in
<linux/atomic.h>, but:
* It is formatted a little differently due to scripting ensuring things
are more regular than they used to be.
* Fallbacks are now expanded in-place as static inline functions rather
than macros.
* The prototypes for fallbacks are arragned consistently with the return
type on a separate line to try to keep to a sensible line length.
There should be no functional change as a result of this patch.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: catalin.marinas@arm.com
Cc: linuxdrivers@attotech.com
Cc: dvyukov@google.com
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: arnd@arndb.de
Cc: aryabinin@virtuozzo.com
Cc: glider@google.com
Link: http://lkml.kernel.org/r/20180904104830.2975-3-mark.rutland@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
