[PATCH] ACPI: Read TSC upon resume
From: Sameer Nanda
Date: Wed Oct 06 2010 - 19:16:01 EST
Read the TSC upon resuming and print it out. This is useful
in helping figure out amount of time spent in the BIOS when
resuming from suspend.
Change-Id: I1d6a32bd62421becddecd152d561763e5f3e1101
Signed-off-by: Sameer Nanda <snanda@xxxxxxxxxxxx>
---
drivers/acpi/sleep.c | 4 ++++
1 files changed, 4 insertions(+), 0 deletions(-)
diff --git a/drivers/acpi/sleep.c b/drivers/acpi/sleep.c
index c0fed2e..f0588fa 100644
--- a/drivers/acpi/sleep.c
+++ b/drivers/acpi/sleep.c
@@ -214,6 +214,7 @@ static int acpi_suspend_enter(suspend_state_t pm_state)
acpi_status status = AE_OK;
unsigned long flags = 0;
u32 acpi_state = acpi_target_sleep_state;
+ u64 tsc;
ACPI_FLUSH_CPU_CACHE();
@@ -235,6 +236,9 @@ static int acpi_suspend_enter(suspend_state_t pm_state)
case ACPI_STATE_S3:
do_suspend_lowlevel();
+ rdtscll(tsc);
+ printk(KERN_INFO "TSC at resume: %llu\n",
+ (unsigned long long)tsc);
break;
}
--
1.7.1
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