| Message ID | 20180710152146.2371336-1-arnd@arndb.de |
|---|---|
| State | Accepted |
| Commit | 88b7210c81096c018f5836aff4749743c0d34623 |
| Headers | show |
| Series | block: iolatency: avoid 64-bit division | expand |
On Tue, Jul 10, 2018 at 05:21:34PM +0200, Arnd Bergmann wrote: > On 32-bit architectures, dividing a 64-bit number needs to use the > do_div() function or something like it to avoid a link failure: > > block/blk-iolatency.o: In function `iolatency_prfill_limit': > blk-iolatency.c:(.text+0x8cc): undefined reference to `__aeabi_uldivmod' > > Using div_u64() gives us the best output and avoids the need for an > explicit cast. > > Fixes: d70675121546 ("block: introduce blk-iolatency io controller") > Signed-off-by: Arnd Bergmann <arnd@arndb.de> Oops sorry Arnd, Reviewed-by: Josef Bacik <josef@toxicpanda.com>
On 7/10/18 9:21 AM, Arnd Bergmann wrote: > On 32-bit architectures, dividing a 64-bit number needs to use the > do_div() function or something like it to avoid a link failure: > > block/blk-iolatency.o: In function `iolatency_prfill_limit': > blk-iolatency.c:(.text+0x8cc): undefined reference to `__aeabi_uldivmod' > > Using div_u64() gives us the best output and avoids the need for an > explicit cast. Applied, thanks Arnd. -- Jens Axboe
diff --git a/block/blk-iolatency.c b/block/blk-iolatency.c index a35a1f580337..56ddb2c68752 100644 --- a/block/blk-iolatency.c +++ b/block/blk-iolatency.c @@ -798,8 +798,7 @@ static u64 iolatency_prfill_limit(struct seq_file *sf, if (!dname || !iolat->min_lat_nsec) return 0; seq_printf(sf, "%s target=%llu\n", - dname, - (unsigned long long)iolat->min_lat_nsec / NSEC_PER_USEC); + dname, div_u64(iolat->min_lat_nsec, NSEC_PER_USEC)); return 0; }
On 32-bit architectures, dividing a 64-bit number needs to use the do_div() function or something like it to avoid a link failure: block/blk-iolatency.o: In function `iolatency_prfill_limit': blk-iolatency.c:(.text+0x8cc): undefined reference to `__aeabi_uldivmod' Using div_u64() gives us the best output and avoids the need for an explicit cast. Fixes: d70675121546 ("block: introduce blk-iolatency io controller") Signed-off-by: Arnd Bergmann <arnd@arndb.de> --- block/blk-iolatency.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) -- 2.9.0