hwmon: (dell-smm) Rework SMM function debugging

Drop #ifdef DEBUG and use ktime_us_delta()
for improved precision.

Signed-off-by: Armin Wolf <W_Armin@gmx.de>
Reviewed-by: Pali Rohár <pali@kernel.org>
Link: https://lore.kernel.org/r/20210814190516.26718-1-W_Armin@gmx.de
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

diff --git a/drivers/hwmon/dell-smm-hwmon.c b/drivers/hwmon/dell-smm-hwmon.c
index f93baf1..774c1b0 100644 (file)
--- a/drivers/hwmon/dell-smm-hwmon.c
+++ b/drivers/hwmon/dell-smm-hwmon.c
@@ -158,17 +158,12 @@ static inline const char __init *i8k_get_dmi_data(int field)
  */
 static int i8k_smm_func(void *par)
 {
-       int rc;
+       ktime_t calltime = ktime_get();
        struct smm_regs *regs = par;
        int eax = regs->eax;
-
-#ifdef DEBUG
        int ebx = regs->ebx;
-       unsigned long duration;
-       ktime_t calltime, delta, rettime;
-
-       calltime = ktime_get();
-#endif
+       long long duration;
+       int rc;
 
        /* SMM requires CPU 0 */
        if (smp_processor_id() != 0)
@@ -230,13 +225,9 @@ static int i8k_smm_func(void *par)
        if (rc != 0 || (regs->eax & 0xffff) == 0xffff || regs->eax == eax)
                rc = -EINVAL;
 
-#ifdef DEBUG
-       rettime = ktime_get();
-       delta = ktime_sub(rettime, calltime);
-       duration = ktime_to_ns(delta) >> 10;
-       pr_debug("smm(0x%.4x 0x%.4x) = 0x%.4x  (took %7lu usecs)\n", eax, ebx,
-               (rc ? 0xffff : regs->eax & 0xffff), duration);
-#endif
+       duration = ktime_us_delta(ktime_get(), calltime);
+       pr_debug("smm(0x%.4x 0x%.4x) = 0x%.4x  (took %7lld usecs)\n", eax, ebx,
+                (rc ? 0xffff : regs->eax & 0xffff), duration);
 
        return rc;
 }