The following commit has been merged into the core/rcu branch of tip: Commit-ID: 7c944d7c67daee84e3c756bb74ad2f32b28c41cf Gitweb: https://git.kernel.org/tip/7c944d7c67daee84e3c756bb74ad2f32b28c41cf Author: Arnd Bergmann <arnd@xxxxxxxx> AuthorDate: Fri, 29 May 2020 14:36:26 -07:00 Committer: Paul E. McKenney <paulmck@xxxxxxxxxx> CommitterDate: Mon, 29 Jun 2020 12:00:45 -07:00 refperf: Work around 64-bit division A 64-bit division was introduced in refperf, breaking compilation on all 32-bit architectures: kernel/rcu/refperf.o: in function `main_func': refperf.c:(.text+0x57c): undefined reference to `__aeabi_uldivmod' Fix this by using div_u64 to mark the expensive operation. [ paulmck: Update primitive and format per Nathan Chancellor. ] Fixes: bd5b16d6c88d ("refperf: Allow decimal nanoseconds") Reported-by: kbuild test robot <lkp@xxxxxxxxx> Reported-by: Valdis Klētnieks <valdis.kletnieks@xxxxxx> Acked-by: Randy Dunlap <rdunlap@xxxxxxxxxxxxx> # build-tested Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx> Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxx> --- kernel/rcu/refperf.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/kernel/rcu/refperf.c b/kernel/rcu/refperf.c index 063eeb0..80d4490 100644 --- a/kernel/rcu/refperf.c +++ b/kernel/rcu/refperf.c @@ -478,7 +478,7 @@ static int main_func(void *arg) if (torture_must_stop()) goto end; - result_avg[exp] = 1000 * process_durations(nreaders) / (nreaders * loops); + result_avg[exp] = div_u64(1000 * process_durations(nreaders), nreaders * loops); } // Print the average of all experiments @@ -489,9 +489,13 @@ static int main_func(void *arg) strcat(buf, "Runs\tTime(ns)\n"); for (exp = 0; exp < nruns; exp++) { + u64 avg; + u32 rem; + if (errexit) break; - sprintf(buf1, "%d\t%llu.%03d\n", exp + 1, result_avg[exp] / 1000, (int)(result_avg[exp] % 1000)); + avg = div_u64_rem(result_avg[exp], 1000, &rem); + sprintf(buf1, "%d\t%llu.%03u\n", exp + 1, avg, rem); strcat(buf, buf1); }
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