blk-iocost: avoid 64-bit division in ioc_timer_fn
authorArnd Bergmann <arnd@arndb.de>
Wed, 18 Jan 2023 08:07:01 +0000 (09:07 +0100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 11 May 2023 14:03:41 +0000 (23:03 +0900)
commita744060574889927f2c22a0562d69aa820e3c9e1
tree48758c76af7b780c66cffbfc5fd89fd585fa55e0
parent7ac1a137beb391198a888f1ba24d42d664717f91
blk-iocost: avoid 64-bit division in ioc_timer_fn

commit 5f2779dfa7b8cc7dfd4a1b6586d86e0d193266f3 upstream.

The behavior of 'enum' types has changed in gcc-13, so now the
UNBUSY_THR_PCT constant is interpreted as a 64-bit number because
it is defined as part of the same enum definition as some other
constants that do not fit within a 32-bit integer. This in turn
leads to some inefficient code on 32-bit architectures as well
as a link error:

arm-linux-gnueabi/bin/arm-linux-gnueabi-ld: block/blk-iocost.o: in function `ioc_timer_fn':
blk-iocost.c:(.text+0x68e8): undefined reference to `__aeabi_uldivmod'
arm-linux-gnueabi-ld: blk-iocost.c:(.text+0x6908): undefined reference to `__aeabi_uldivmod'

Split the enum definition to keep the 64-bit timing constants in
a separate enum type from those constants that can clearly fit
within a smaller type.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20230118080706.3303186-1-arnd@kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
block/blk-iocost.c