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| author | Heiko Carstens <hca@linux.ibm.com> | 2025-02-10 09:56:53 +0100 |
|---|---|---|
| committer | Vasily Gorbik <gor@linux.ibm.com> | 2025-02-11 19:35:08 +0100 |
| commit | 6166caf3bbe2429e4fac71b77e1c8254f2690383 (patch) | |
| tree | d778e371ff5d315f4780a081ee0e0156988801fb | |
| parent | 32ae4a2992529e2c7934e422035fad1d9b0f1fb5 (diff) | |
s390/bitops: Disable arch_test_bit() optimization for PROFILE_ALL_BRANCHES
With PROFILE_ALL_BRANCHES enabled gcc sometimes fails to handle
__builtin_constant_p() correctly:
In function 'arch_test_bit',
inlined from 'node_state' at include/linux/nodemask.h:423:9,
inlined from 'warn_if_node_offline' at include/linux/gfp.h:252:2,
inlined from '__alloc_pages_node_noprof' at include/linux/gfp.h:267:2,
inlined from 'alloc_pages_node_noprof' at include/linux/gfp.h:296:9,
inlined from 'vm_area_alloc_pages.constprop' at mm/vmalloc.c:3591:11:
>> arch/s390/include/asm/bitops.h:60:17: warning: 'asm' operand 2 probably does not match constraints
60 | asm volatile(
| ^~~
>> arch/s390/include/asm/bitops.h:60:17: error: impossible constraint in 'asm'
Therefore disable the optimization for this case. This is similar to
commit 63678eecec57 ("s390/preempt: disable __preempt_count_add()
optimization for PROFILE_ALL_BRANCHES")
Fixes: b2bc1b1a77c0 ("s390/bitops: Provide optimized arch_test_bit()")
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202502091912.xL2xTCGw-lkp@intel.com/
Acked-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
| -rw-r--r-- | arch/s390/include/asm/bitops.h | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/arch/s390/include/asm/bitops.h b/arch/s390/include/asm/bitops.h index d5125296ade2..a5ca0a947691 100644 --- a/arch/s390/include/asm/bitops.h +++ b/arch/s390/include/asm/bitops.h @@ -53,7 +53,11 @@ static __always_inline bool arch_test_bit(unsigned long nr, const volatile unsig unsigned long mask; int cc; - if (__builtin_constant_p(nr)) { + /* + * With CONFIG_PROFILE_ALL_BRANCHES enabled gcc fails to + * handle __builtin_constant_p() in some cases. + */ + if (!IS_ENABLED(CONFIG_PROFILE_ALL_BRANCHES) && __builtin_constant_p(nr)) { addr = (const volatile unsigned char *)ptr; addr += (nr ^ (BITS_PER_LONG - BITS_PER_BYTE)) / BITS_PER_BYTE; mask = 1UL << (nr & (BITS_PER_BYTE - 1)); |