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| author | Heiko Carstens <heiko.carstens@de.ibm.com> | 2015-11-24 13:48:27 +0100 |
|---|---|---|
| committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2015-12-18 14:59:23 +0100 |
| commit | 6ab6c31a5450b73133e04c3976469d6d72f55df3 (patch) | |
| tree | a9a07f28080e174b44deb196d9df64fb31c22c17 /arch/s390/include/asm/facility.h | |
| parent | s390/facilities: remove unneeded facility bits (diff) | |
| download | linux-6ab6c31a5450b73133e04c3976469d6d72f55df3.tar.xz linux-6ab6c31a5450b73133e04c3976469d6d72f55df3.zip | |
s390/facilities: optimize test_facility()
test_facility() can be optimized for bits which must be set anyway,
due to the check in head.S. This removes a couple of superfluous
runtime checks.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'arch/s390/include/asm/facility.h')
| -rw-r--r-- | arch/s390/include/asm/facility.h | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/arch/s390/include/asm/facility.h b/arch/s390/include/asm/facility.h index 007163f91856..09b406db7529 100644 --- a/arch/s390/include/asm/facility.h +++ b/arch/s390/include/asm/facility.h @@ -34,6 +34,12 @@ static inline int __test_facility(unsigned long nr, void *facilities) */ static inline int test_facility(unsigned long nr) { + unsigned long facilities_als[] = { FACILITIES_ALS }; + + if (__builtin_constant_p(nr) && nr < sizeof(facilities_als) * 8) { + if (__test_facility(nr, &facilities_als)) + return 1; + } return __test_facility(nr, &S390_lowcore.stfle_fac_list); } |