kernel/linux.git/lib/crc32.c, branch v4.14.307

lib/crc32.c: fix trivial typo in preprocessor condition

2020-10-29T08:07:10+00:00

[ Upstream commit 904542dc56524f921a6bab0639ff6249c01e775f ] Whether crc32_be needs a lookup table is chosen based on CRC_LE_BITS. Obviously, the _be function should be governed by the _BE_ define. This probably never pops up as it's hard to come up with a configuration where CRC_BE_BITS isn't the same as CRC_LE_BITS and as nobody is using bitwise CRC anyway. Fixes: 46c5801eaf86 ("crc32: bolt on crc32c") Signed-off-by: Tobias Jordan Signed-off-by: Andrew Morton Cc: Krzysztof Kozlowski Cc: Jonathan Corbet Cc: Mauro Carvalho Chehab Link: https://lkml.kernel.org/r/20200923182122.GA3338@agrajag.zerfleddert.de Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin

lib: add module support to crc32 tests

2017-02-25T01:46:57+00:00

Extract the crc32 test code into its own source file, to allow to compile it either to a loadable module, or builtin into the kernel. Link: http://lkml.kernel.org/r/1483470276-10517-1-git-send-email-geert@linux-m68k.org Signed-off-by: Geert Uytterhoeven Reviewed-by: Andy Shevchenko Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

crc32: use ktime_get_ns() for measurement

2016-08-02T23:35:08+00:00

The crc32 test function measures the elapsed time in nanoseconds, but uses 'struct timespec' for that. We want to remove timespec from the kernel for y2038 compatibility, and ktime_get_ns() also helps make the code simpler here. It is also slightly better to use monontonic time, as we are only interested in the time difference. Link: http://lkml.kernel.org/r/20160617143932.3289626-1-arnd@arndb.de Signed-off-by: Arnd Bergmann Cc: "David S . Miller" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

lib: crc32: Add some additional __pure annotations

2014-06-25T23:04:00+00:00

In case they help the compiler. Signed-off-by: George Spelvin Signed-off-by: Daniel Borkmann Signed-off-by: David S. Miller

lib: crc32: Mark test data __initconst

2014-06-25T23:03:59+00:00

So it gets discarded after the selftest. Signed-off-by: George Spelvin Signed-off-by: Daniel Borkmann Signed-off-by: David S. Miller

lib: crc32: Greatly shrink CRC combining code

2014-06-25T23:03:59+00:00

There's no need for a full 32x32 matrix, when rows before the last are just shifted copies of the rows after them. There's still room for improvement (especially on X86 processors with CRC32 and PCLMUL instructions), but this is a large step in the right direction [which is in particular useful for its current user, namely SCTP checksumming over multiple skb frags[] entries, i.e. in IPVS balancing when other CRC32 offloads are not available]. The internal primitive is now called crc32_generic_shift and takes one less argument; the XOR with crc2 is done in inline wrappers. Signed-off-by: George Spelvin Signed-off-by: Daniel Borkmann Signed-off-by: David S. Miller

lib/crc32.c: remove unnecessary __constant

2014-06-04T23:54:19+00:00

Use cpu_to_le32 instead of __constant_cpu_to_le32. Signed-off-by: Fabian Frederick Cc: "David S. Miller" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

lib: crc32: reduce number of cases for crc32{, c}_combine

2013-11-04T20:27:08+00:00

We can safely reduce the number of test cases by a tenth. There is no particular need to run as many as we're running now for crc32{,c}_combine, that gives us still ~8000 tests we're doing if people run kernels with crc selftests enabled which is perfectly fine. Signed-off-by: Daniel Borkmann Signed-off-by: David S. Miller

lib: crc32: conditionally resched when running testcases

2013-11-04T20:27:08+00:00

Fengguang reports that when crc32 selftests are running on startup, on some e.g. 32bit systems, we can get a CPU stall like "INFO: rcu_sched self-detected stall on CPU { 0} (t=2101 jiffies g=4294967081 c=4294967080 q=41)". As this is not intended, add a cond_resched() at the end of a test case to fix it. Introduced by efba721f63 ("lib: crc32: add test cases for crc32{, c}_combine routines"). Reported-by: Fengguang Wu Signed-off-by: Daniel Borkmann Signed-off-by: David S. Miller

lib: crc32: add test cases for crc32{, c}_combine routines

2013-11-04T04:04:56+00:00

We already have 100 test cases for crcs itself, so split the test buffer with a-prio known checksums, and test crc of two blocks against crc of the whole block for the same results. Output/result with CONFIG_CRC32_SELFTEST=y: [ 2.687095] crc32: CRC_LE_BITS = 64, CRC_BE BITS = 64 [ 2.687097] crc32: self tests passed, processed 225944 bytes in 278177 nsec [ 2.687383] crc32c: CRC_LE_BITS = 64 [ 2.687385] crc32c: self tests passed, processed 225944 bytes in 141708 nsec [ 7.336771] crc32_combine: 113072 self tests passed [ 12.050479] crc32c_combine: 113072 self tests passed [ 17.633089] alg: No test for crc32 (crc32-pclmul) Signed-off-by: Daniel Borkmann Cc: linux-kernel@vger.kernel.org Signed-off-by: David S. Miller