From: Dominik Brodowski <linux@xxxxxxxxxxxxxxxxxxxx>
Do not assume there was bus mastering activity if the idle handler didn't get
called, as there's only reason to not enter C3-type sleep if there is bus
master activity going on. Only for the "promotion" into C3-type sleep bus
mastering activity is taken into account, and there only current bus mastering
activity, and not pure guessing should lead to the decision on whether to
enter C3-type sleep or not.
Also, as bm_activity is a jiffy-based bitmask (bit 0: bus mastering activity
during this juffy, bit 31: bus mastering activity 31 jiffies ago), fix the
setting of bit 0, as it might be called multiple times within one jiffy.
Signed-off-by: Dominik Brodowski <linux@xxxxxxxxxxxxxxxxxxxx>
Cc: <linux-acpi@xxxxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxx>
---
drivers/acpi/processor_idle.c | 18 ++++++------------
1 file changed, 6 insertions(+), 12 deletions(-)
diff -puN drivers/acpi/processor_idle.c~acpi-c-states-bm_activity-improvements drivers/acpi/processor_idle.c
--- a/drivers/acpi/processor_idle.c~acpi-c-states-bm_activity-improvements
+++ a/drivers/acpi/processor_idle.c
@@ -3,7 +3,7 @@
*
* Copyright (C) 2001, 2002 Andy Grover <andrew.grover@xxxxxxxxx>
* Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@xxxxxxxxx>
- * Copyright (C) 2004 Dominik Brodowski <linux@xxxxxxxx>
+ * Copyright (C) 2004, 2005 Dominik Brodowski <linux@xxxxxxxx>
* Copyright (C) 2004 Anil S Keshavamurthy <anil.s.keshavamurthy@xxxxxxxxx>
* - Added processor hotplug support
* Copyright (C) 2005 Venkatesh Pallipadi <venkatesh.pallipadi@xxxxxxxxx>
@@ -264,21 +264,15 @@ static void acpi_processor_idle(void)
u32 bm_status = 0;
unsigned long diff = jiffies - pr->power.bm_check_timestamp;
- if (diff > 32)
- diff = 32;
+ if (diff > 31)
+ diff = 31;
- while (diff) {
- /* if we didn't get called, assume there was busmaster activity */
- diff--;
- if (diff)
- pr->power.bm_activity |= 0x1;
- pr->power.bm_activity <<= 1;
- }
+ pr->power.bm_activity <<= diff;
acpi_get_register(ACPI_BITREG_BUS_MASTER_STATUS,
&bm_status, ACPI_MTX_DO_NOT_LOCK);
if (bm_status) {
- pr->power.bm_activity++;
+ pr->power.bm_activity |= 0x1;
acpi_set_register(ACPI_BITREG_BUS_MASTER_STATUS,
1, ACPI_MTX_DO_NOT_LOCK);
}
@@ -290,7 +284,7 @@ static void acpi_processor_idle(void)
else if (errata.piix4.bmisx) {
if ((inb_p(errata.piix4.bmisx + 0x02) & 0x01)
|| (inb_p(errata.piix4.bmisx + 0x0A) & 0x01))
- pr->power.bm_activity++;
+ pr->power.bm_activity |= 0x1;
}
pr->power.bm_check_timestamp = jiffies;
_
-
To unsubscribe from this list: send the line "unsubscribe linux-acpi" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
