diff options
| author | Pali Rohár | 2016-06-18 00:54:49 +0200 |
|---|---|---|
| committer | Guenter Roeck | 2016-06-27 18:58:03 -0700 |
| commit | 9d58bec0966bfc87948244b81056137e6d214e04 (patch) | |
| tree | 493334143c74d8663b72d3c0b6aa06c63c5460fb /drivers/hwmon | |
| parent | 747bc8b063ae6b66447918280922253721cb1d9b (diff) | |
hwmon: (dell-smm) In debug mode log duration of SMM calls
This allow us to debug how long take each SMM call and how long is system
frozen in SMM handler.
Signed-off-by: Pali Rohár <pali.rohar@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Diffstat (limited to 'drivers/hwmon')
| -rw-r--r-- | drivers/hwmon/dell-smm-hwmon.c | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/drivers/hwmon/dell-smm-hwmon.c b/drivers/hwmon/dell-smm-hwmon.c index 571d4984d39c..acf9c0361d9f 100644 --- a/drivers/hwmon/dell-smm-hwmon.c +++ b/drivers/hwmon/dell-smm-hwmon.c @@ -140,6 +140,14 @@ static int i8k_smm(struct smm_regs *regs) int eax = regs->eax; cpumask_var_t old_mask; +#ifdef DEBUG + int ebx = regs->ebx; + unsigned long duration; + ktime_t calltime, delta, rettime; + + calltime = ktime_get(); +#endif + /* SMM requires CPU 0 */ if (!alloc_cpumask_var(&old_mask, GFP_KERNEL)) return -ENOMEM; @@ -211,6 +219,15 @@ static int i8k_smm(struct smm_regs *regs) out: set_cpus_allowed_ptr(current, old_mask); free_cpumask_var(old_mask); + +#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 + return rc; } |