[PATCH] iommu/vt-d: Fix linker error on 32-bit

From: Joerg Roedel
Date: Thu Jun 10 2021 - 04:31:55 EST


From: Joerg Roedel <jroedel@xxxxxxx>

A recent commit broke the build on 32-bit x86. The linker throws these
messages:

ld: drivers/iommu/intel/perf.o: in function `dmar_latency_snapshot':
perf.c:(.text+0x40c): undefined reference to `__udivdi3'
ld: perf.c:(.text+0x458): undefined reference to `__udivdi3'

The reason are the 64-bit divides in dmar_latency_snapshot(). Use the
div_u64() helper function for those.

Fixes: 55ee5e67a59a ("iommu/vt-d: Add common code for dmar latency performance monitors")
Signed-off-by: Joerg Roedel <jroedel@xxxxxxx>
---
drivers/iommu/intel/perf.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/iommu/intel/perf.c b/drivers/iommu/intel/perf.c
index faaa96dda437..73b7ec705552 100644
--- a/drivers/iommu/intel/perf.c
+++ b/drivers/iommu/intel/perf.c
@@ -141,14 +141,14 @@ int dmar_latency_snapshot(struct intel_iommu *iommu, char *str, size_t size)
if (val == UINT_MAX)
val = 0;
else
- val /= 1000;
+ val = div_u64(val, 1000);
break;
case COUNTS_MAX:
- val /= 1000;
+ val = div_u64(val, 1000);
break;
case COUNTS_SUM:
if (lstat[i].samples)
- val /= (lstat[i].samples * 1000);
+ val = div_u64(val, (lstat[i].samples * 1000));
else
val = 0;
break;
--
2.31.1