2006-10-06 18:58:24

by Daniel Walker

Subject: [PATCH 08/10] -mm: clocksource: initialize list value

A change to clocksource initialization. It's optional for new clocksources,
but prefered. If the list field is initialized it allows clocksource_register
to complete faster since it doesn't have the scan the list of clocks doing
strcmp on each.

Signed-Off-By: Daniel Walker <[email protected]>

---
arch/i386/kernel/hpet.c | 1 +
arch/i386/kernel/i8253.c | 1 +
arch/i386/kernel/tsc.c | 1 +
drivers/clocksource/acpi_pm.c | 1 +
drivers/clocksource/cyclone.c | 1 +
drivers/clocksource/scx200_hrt.c | 1 +
include/linux/clocksource.h | 3 +++
7 files changed, 9 insertions(+)

Index: linux-2.6.18/arch/i386/kernel/hpet.c
===================================================================
--- linux-2.6.18.orig/arch/i386/kernel/hpet.c
+++ linux-2.6.18/arch/i386/kernel/hpet.c
@@ -27,6 +27,7 @@ static struct clocksource clocksource_hp
.mult = 0, /* set below */
.shift = HPET_SHIFT,
.is_continuous = 1,
+ .list = CLOCKSOURCE_LIST_INIT(clocksource_hpet.list),
};

static int __init init_hpet_clocksource(void)
Index: linux-2.6.18/arch/i386/kernel/i8253.c
===================================================================
--- linux-2.6.18.orig/arch/i386/kernel/i8253.c
+++ linux-2.6.18/arch/i386/kernel/i8253.c
@@ -105,6 +105,7 @@ static struct clocksource clocksource_pi
.mask = CLOCKSOURCE_MASK(32),
.mult = 0,
.shift = 20,
+ .list = CLOCKSOURCE_LIST_INIT(clocksource_pit.list),
};

static int __init init_pit_clocksource(void)
Index: linux-2.6.18/arch/i386/kernel/tsc.c
===================================================================
--- linux-2.6.18.orig/arch/i386/kernel/tsc.c
+++ linux-2.6.18/arch/i386/kernel/tsc.c
@@ -350,6 +350,7 @@ static struct clocksource clocksource_ts
.mult = 0, /* to be set */
.shift = 22,
.is_continuous = 1,
+ .list = CLOCKSOURCE_LIST_INIT(clocksource_tsc.list),
};


Index: linux-2.6.18/drivers/clocksource/acpi_pm.c
===================================================================
--- linux-2.6.18.orig/drivers/clocksource/acpi_pm.c
+++ linux-2.6.18/drivers/clocksource/acpi_pm.c
@@ -73,6 +73,7 @@ static struct clocksource clocksource_ac
.mult = 0, /*to be caluclated*/
.shift = 22,
.is_continuous = 1,
+ .list = CLOCKSOURCE_LIST_INIT(clocksource_acpi_pm.list),
};


Index: linux-2.6.18/drivers/clocksource/cyclone.c
===================================================================
--- linux-2.6.18.orig/drivers/clocksource/cyclone.c
+++ linux-2.6.18/drivers/clocksource/cyclone.c
@@ -32,6 +32,7 @@ static struct clocksource clocksource_cy
.mult = 10,
.shift = 0,
.is_continuous = 1,
+ .list = CLOCKSOURCE_LIST_INIT(clocksource_cyclone.list),
};

static int __init init_cyclone_clocksource(void)
Index: linux-2.6.18/drivers/clocksource/scx200_hrt.c
===================================================================
--- linux-2.6.18.orig/drivers/clocksource/scx200_hrt.c
+++ linux-2.6.18/drivers/clocksource/scx200_hrt.c
@@ -58,6 +58,7 @@ static struct clocksource cs_hrt = {
.read = read_hrt,
.mask = CLOCKSOURCE_MASK(32),
.is_continuous = 1,
+ .list = CLOCKSOURCE_LIST_INIT(cs_hrt.list),
/* mult, shift are set based on mhz27 flag */
};

Index: linux-2.6.18/include/linux/clocksource.h
===================================================================
--- linux-2.6.18.orig/include/linux/clocksource.h
+++ linux-2.6.18/include/linux/clocksource.h
@@ -82,6 +82,9 @@ struct clocksource {
/* simplify initialization of mask field */
#define CLOCKSOURCE_MASK(bits) (cycle_t)(bits<64 ? ((1ULL<<bits)-1) : -1)

+/* Abstracted list initialization */
+#define CLOCKSOURCE_LIST_INIT(x) LIST_HEAD_INIT(x)
+
/**
* clocksource_khz2mult - calculates mult from khz and shift
* @khz: Clocksource frequency in KHz

--

2006-10-09 19:59:51

by john stultz

Subject: Re: [PATCH 08/10] -mm: clocksource: initialize list value

On Fri, 2006-10-06 at 11:54 -0700, Daniel Walker wrote:
> plain text document attachment (clocksouce_list_init.patch)
> A change to clocksource initialization. It's optional for new clocksources,
> but prefered. If the list field is initialized it allows clocksource_register
> to complete faster since it doesn't have the scan the list of clocks doing
> strcmp on each.
>
> Signed-Off-By: Daniel Walker <[email protected]>

I dont' have any comments that haven't been said:

Drop the CLOCKSOURCE_LIST_INIT define, and make it required. Its easy
enough to add.

thanks
-john