2 files changed, 4 insertions, 2 deletions

diff --git a/drivers/scsi/ipr.c b/drivers/scsi/ipr.c
index 486ffaf5109a..7ae9cd743eb2 100644
--- a/drivers/scsi/ipr.c
+++ b/drivers/scsi/ipr.c
@@ -599,9 +599,10 @@ static void ipr_trc_hook(struct ipr_cmnd *ipr_cmd,
 {
         struct ipr_trace_entry *trace_entry;
         struct ipr_ioa_cfg *ioa_cfg = ipr_cmd->ioa_cfg;
+        unsigned int trace_index;
 
-        trace_entry = &ioa_cfg->trace[atomic_add_return
-                        (1, &ioa_cfg->trace_index)%IPR_NUM_TRACE_ENTRIES];
+        trace_index = atomic_add_return(1, &ioa_cfg->trace_index) & IPR_TRACE_INDEX_MASK;
+        trace_entry = &ioa_cfg->trace[trace_index];
         trace_entry->time = jiffies;
         trace_entry->op_code = ipr_cmd->ioarcb.cmd_pkt.cdb[0];
         trace_entry->type = type;
diff --git a/drivers/scsi/ipr.h b/drivers/scsi/ipr.h
index 73790a1d0969..6b97ee45c7b4 100644
--- a/drivers/scsi/ipr.h
+++ b/drivers/scsi/ipr.h
@@ -1486,6 +1486,7 @@ struct ipr_ioa_cfg {
 
 #define IPR_NUM_TRACE_INDEX_BITS        8
 #define IPR_NUM_TRACE_ENTRIES           (1 << IPR_NUM_TRACE_INDEX_BITS)
+#define IPR_TRACE_INDEX_MASK            (IPR_NUM_TRACE_ENTRIES - 1)
 #define IPR_TRACE_SIZE  (sizeof(struct ipr_trace_entry) * IPR_NUM_TRACE_ENTRIES)
         char trace_start[8];
 #define IPR_TRACE_START_LABEL                   "trace"