[PATCH] workqueue: avoid unguarded 64-bit division

From: Arnd Bergmann

Date: Thu Apr 02 2026 - 16:59:32 EST


From: Arnd Bergmann <arnd@xxxxxxxx>

The printk() requires a division that is not allowed on 32-bit architectures:

x86_64-linux-ld: lib/test_workqueue.o: in function `test_workqueue_init':
test_workqueue.c:(.init.text+0x36f): undefined reference to `__udivdi3'

Use div_u64() to print the resulting elapsed microseconds.

Fixes: 24b2e73f9700 ("workqueue: add test_workqueue benchmark module")
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
lib/test_workqueue.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/test_workqueue.c b/lib/test_workqueue.c
index f2ae1ac4bd93..99e160bd5ad1 100644
--- a/lib/test_workqueue.c
+++ b/lib/test_workqueue.c
@@ -242,7 +242,7 @@ static int __init run_bench(int n_threads, const char *scope, const char *label)

pr_info("test_workqueue: %-16s %llu items/sec\tp50=%llu\tp90=%llu\tp95=%llu ns\n",
label,
- elapsed_us ? total_items * 1000000ULL / elapsed_us : 0,
+ elapsed_us ? div_u64(total_items * 1000000ULL, elapsed_us) : 0,
all_latencies[total_items * 50 / 100],
all_latencies[total_items * 90 / 100],
all_latencies[total_items * 95 / 100]);
--
2.39.5