2009-03-11 06:04:25

by Rusty Russell

Subject: [PATCH] cpumask: x86 mmio-mod.c use cpumask_var_t for downed_cpus.

Impact: cleanup, reduce memory usage for CONFIG_CPUMASK_OFFSTACK=y

Part of the "getting rid of obsolete cpumask_t" patch:
1) Use cpumask_var_t: this is a pointer if CONFIG_CPUMASK_OFFSTACK=y
2) Call alloc_cpumask_var() on first entry into enter_uniprocessor()
3) Use modern cpumask_* functions.

To: Pekka Paalanen <[email protected]>
Signed-off-by: Rusty Russell <[email protected]>
---
arch/x86/mm/mmio-mod.c | 19 +++++++++++++------
1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/arch/x86/mm/mmio-mod.c b/arch/x86/mm/mmio-mod.c
--- a/arch/x86/mm/mmio-mod.c
+++ b/arch/x86/mm/mmio-mod.c
@@ -378,27 +378,34 @@ static void clear_trace_list(void)
}

#ifdef CONFIG_HOTPLUG_CPU
-static cpumask_t downed_cpus;
+static cpumask_var_t downed_cpus;

static void enter_uniprocessor(void)
{
int cpu;
int err;

+ if (downed_cpus == NULL &&
+ !alloc_cpumask_var(&downed_cpus, GFP_KERNEL)) {
+ pr_notice(NAME "Failed to allocate mask\n");
+ goto out;
+ }
+
get_online_cpus();
- downed_cpus = cpu_online_map;
- cpu_clear(first_cpu(cpu_online_map), downed_cpus);
+ cpumask_copy(downed_cpus, cpu_online_mask);
+ cpumask_clear_cpu(cpumask_first(cpu_online_mask), downed_cpus);
if (num_online_cpus() > 1)
pr_notice(NAME "Disabling non-boot CPUs...\n");
put_online_cpus();

- for_each_cpu_mask(cpu, downed_cpus) {
+ for_each_cpu(cpu, downed_cpus) {
err = cpu_down(cpu);
if (!err)
pr_info(NAME "CPU%d is down.\n", cpu);
else
pr_err(NAME "Error taking CPU%d down: %d\n", cpu, err);
}
+out:
if (num_online_cpus() > 1)
pr_warning(NAME "multiple CPUs still online, "
"may miss events.\n");
@@ -411,10 +418,10 @@ static void __ref leave_uniprocessor(voi
int cpu;
int err;

- if (cpus_weight(downed_cpus) == 0)
+ if (downed_cpus == NULL || cpumask_weight(downed_cpus) == 0)
return;
pr_notice(NAME "Re-enabling CPUs...\n");
- for_each_cpu_mask(cpu, downed_cpus) {
+ for_each_cpu(cpu, downed_cpus) {
err = cpu_up(cpu);
if (!err)
pr_info(NAME "enabled CPU%d.\n", cpu);

2009-03-11 11:15:14

by Rusty Russell

Subject: [tip:cpus4096] x86: cpumask: x86 mmio-mod.c use cpumask_var_t for downed_cpus

Commit-ID: f5c14fe200f4315b305ae44e5633cbe62070aaea
Gitweb: http://git.kernel.org/tip/f5c14fe200f4315b305ae44e5633cbe62070aaea
Author: "Rusty Russell" <[email protected]>
AuthorDate: Wed, 11 Mar 2009 16:33:55 +1030
Commit: Ingo Molnar <[email protected]>
CommitDate: Wed, 11 Mar 2009 11:19:47 +0100

x86: cpumask: x86 mmio-mod.c use cpumask_var_t for downed_cpus

Impact: cleanup, reduce memory usage for CONFIG_CPUMASK_OFFSTACK=y

Part of the "getting rid of obsolete cpumask_t" patch:

1) Use cpumask_var_t: this is a pointer if CONFIG_CPUMASK_OFFSTACK=y
2) Call alloc_cpumask_var() on first entry into enter_uniprocessor()
3) Use modern cpumask_* functions.

Signed-off-by: Rusty Russell <[email protected]>
Cc: Pekka Paalanen <[email protected]>
LKML-Reference: <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>


---
arch/x86/mm/mmio-mod.c | 19 +++++++++++++------
1 files changed, 13 insertions(+), 6 deletions(-)

diff --git a/arch/x86/mm/mmio-mod.c b/arch/x86/mm/mmio-mod.c
index 2c4baa8..c9342ed 100644
--- a/arch/x86/mm/mmio-mod.c
+++ b/arch/x86/mm/mmio-mod.c
@@ -378,27 +378,34 @@ static void clear_trace_list(void)
}

#ifdef CONFIG_HOTPLUG_CPU
-static cpumask_t downed_cpus;
+static cpumask_var_t downed_cpus;

static void enter_uniprocessor(void)
{
int cpu;
int err;

+ if (downed_cpus == NULL &&
+ !alloc_cpumask_var(&downed_cpus, GFP_KERNEL)) {
+ pr_notice(NAME "Failed to allocate mask\n");
+ goto out;
+ }
+
get_online_cpus();
- downed_cpus = cpu_online_map;
- cpu_clear(first_cpu(cpu_online_map), downed_cpus);
+ cpumask_copy(downed_cpus, cpu_online_mask);
+ cpumask_clear_cpu(cpumask_first(cpu_online_mask), downed_cpus);
if (num_online_cpus() > 1)
pr_notice(NAME "Disabling non-boot CPUs...\n");
put_online_cpus();

- for_each_cpu_mask(cpu, downed_cpus) {
+ for_each_cpu(cpu, downed_cpus) {
err = cpu_down(cpu);
if (!err)
pr_info(NAME "CPU%d is down.\n", cpu);
else
pr_err(NAME "Error taking CPU%d down: %d\n", cpu, err);
}
+out:
if (num_online_cpus() > 1)
pr_warning(NAME "multiple CPUs still online, "
"may miss events.\n");
@@ -411,10 +418,10 @@ static void __ref leave_uniprocessor(void)
int cpu;
int err;

- if (cpus_weight(downed_cpus) == 0)
+ if (downed_cpus == NULL || cpumask_weight(downed_cpus) == 0)
return;
pr_notice(NAME "Re-enabling CPUs...\n");
- for_each_cpu_mask(cpu, downed_cpus) {
+ for_each_cpu(cpu, downed_cpus) {
err = cpu_up(cpu);
if (!err)
pr_info(NAME "enabled CPU%d.\n", cpu);

2009-03-11 17:46:18

by Pekka Paalanen

Subject: Re: [tip:cpus4096] x86: cpumask: x86 mmio-mod.c use cpumask_var_t for downed_cpus

On Wed, 11 Mar 2009 11:13:59 GMT
Rusty Russell <[email protected]> wrote:

> Commit-ID: f5c14fe200f4315b305ae44e5633cbe62070aaea
> Gitweb: http://git.kernel.org/tip/f5c14fe200f4315b305ae44e5633cbe62070aaea
> Author: "Rusty Russell" <[email protected]>
> AuthorDate: Wed, 11 Mar 2009 16:33:55 +1030
> Commit: Ingo Molnar <[email protected]>
> CommitDate: Wed, 11 Mar 2009 11:19:47 +0100
>
> x86: cpumask: x86 mmio-mod.c use cpumask_var_t for downed_cpus
>
> Impact: cleanup, reduce memory usage for CONFIG_CPUMASK_OFFSTACK=y
>
> Part of the "getting rid of obsolete cpumask_t" patch:
>
> 1) Use cpumask_var_t: this is a pointer if CONFIG_CPUMASK_OFFSTACK=y
> 2) Call alloc_cpumask_var() on first entry into enter_uniprocessor()
> 3) Use modern cpumask_* functions.
>
> Signed-off-by: Rusty Russell <[email protected]>
> Cc: Pekka Paalanen <[email protected]>
> LKML-Reference: <[email protected]>
> Signed-off-by: Ingo Molnar <[email protected]>

Acked-by: Pekka Paalanen <[email protected]>

>
>
> ---
> arch/x86/mm/mmio-mod.c | 19 +++++++++++++------
> 1 files changed, 13 insertions(+), 6 deletions(-)
>
> diff --git a/arch/x86/mm/mmio-mod.c b/arch/x86/mm/mmio-mod.c
> index 2c4baa8..c9342ed 100644
> --- a/arch/x86/mm/mmio-mod.c
> +++ b/arch/x86/mm/mmio-mod.c
> @@ -378,27 +378,34 @@ static void clear_trace_list(void)
> }
>
> #ifdef CONFIG_HOTPLUG_CPU
> -static cpumask_t downed_cpus;
> +static cpumask_var_t downed_cpus;
>
> static void enter_uniprocessor(void)
> {
> int cpu;
> int err;
>
> + if (downed_cpus == NULL &&
> + !alloc_cpumask_var(&downed_cpus, GFP_KERNEL)) {
> + pr_notice(NAME "Failed to allocate mask\n");
> + goto out;
> + }
> +
> get_online_cpus();
> - downed_cpus = cpu_online_map;
> - cpu_clear(first_cpu(cpu_online_map), downed_cpus);
> + cpumask_copy(downed_cpus, cpu_online_mask);
> + cpumask_clear_cpu(cpumask_first(cpu_online_mask), downed_cpus);
> if (num_online_cpus() > 1)
> pr_notice(NAME "Disabling non-boot CPUs...\n");
> put_online_cpus();
>
> - for_each_cpu_mask(cpu, downed_cpus) {
> + for_each_cpu(cpu, downed_cpus) {
> err = cpu_down(cpu);
> if (!err)
> pr_info(NAME "CPU%d is down.\n", cpu);
> else
> pr_err(NAME "Error taking CPU%d down: %d\n", cpu, err);
> }
> +out:
> if (num_online_cpus() > 1)
> pr_warning(NAME "multiple CPUs still online, "
> "may miss events.\n");
> @@ -411,10 +418,10 @@ static void __ref leave_uniprocessor(void)
> int cpu;
> int err;
>
> - if (cpus_weight(downed_cpus) == 0)
> + if (downed_cpus == NULL || cpumask_weight(downed_cpus) == 0)
> return;
> pr_notice(NAME "Re-enabling CPUs...\n");
> - for_each_cpu_mask(cpu, downed_cpus) {
> + for_each_cpu(cpu, downed_cpus) {
> err = cpu_up(cpu);
> if (!err)
> pr_info(NAME "enabled CPU%d.\n", cpu);
>


--
Pekka Paalanen
http://www.iki.fi/pq/

2009-03-18 12:59:11

by Rusty Russell

Subject: [tip:cpus4096] x86: cpumask: x86 mmio-mod.c use cpumask_var_t for downed_cpus

Commit-ID: c38da5692e3a4d5d303c04cbf7e526f1eb761076
Gitweb: http://git.kernel.org/tip/c38da5692e3a4d5d303c04cbf7e526f1eb761076
Author: Rusty Russell <[email protected]>
AuthorDate: Wed, 11 Mar 2009 16:33:55 +1030
Commit: Ingo Molnar <[email protected]>
CommitDate: Wed, 18 Mar 2009 13:51:51 +0100

x86: cpumask: x86 mmio-mod.c use cpumask_var_t for downed_cpus

Impact: cleanup, reduce memory usage for CONFIG_CPUMASK_OFFSTACK=y

Part of the "getting rid of obsolete cpumask_t" patch:

1) Use cpumask_var_t: this is a pointer if CONFIG_CPUMASK_OFFSTACK=y
2) Call alloc_cpumask_var() on first entry into enter_uniprocessor()
3) Use modern cpumask_* functions.

Signed-off-by: Rusty Russell <[email protected]>
Cc: Pekka Paalanen <[email protected]>
LKML-Reference: <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>


---
arch/x86/mm/mmio-mod.c | 19 +++++++++++++------
1 files changed, 13 insertions(+), 6 deletions(-)

diff --git a/arch/x86/mm/mmio-mod.c b/arch/x86/mm/mmio-mod.c
index 2c4baa8..c9342ed 100644
--- a/arch/x86/mm/mmio-mod.c
+++ b/arch/x86/mm/mmio-mod.c
@@ -378,27 +378,34 @@ static void clear_trace_list(void)
}

#ifdef CONFIG_HOTPLUG_CPU
-static cpumask_t downed_cpus;
+static cpumask_var_t downed_cpus;

static void enter_uniprocessor(void)
{
int cpu;
int err;

+ if (downed_cpus == NULL &&
+ !alloc_cpumask_var(&downed_cpus, GFP_KERNEL)) {
+ pr_notice(NAME "Failed to allocate mask\n");
+ goto out;
+ }
+
get_online_cpus();
- downed_cpus = cpu_online_map;
- cpu_clear(first_cpu(cpu_online_map), downed_cpus);
+ cpumask_copy(downed_cpus, cpu_online_mask);
+ cpumask_clear_cpu(cpumask_first(cpu_online_mask), downed_cpus);
if (num_online_cpus() > 1)
pr_notice(NAME "Disabling non-boot CPUs...\n");
put_online_cpus();

- for_each_cpu_mask(cpu, downed_cpus) {
+ for_each_cpu(cpu, downed_cpus) {
err = cpu_down(cpu);
if (!err)
pr_info(NAME "CPU%d is down.\n", cpu);
else
pr_err(NAME "Error taking CPU%d down: %d\n", cpu, err);
}
+out:
if (num_online_cpus() > 1)
pr_warning(NAME "multiple CPUs still online, "
"may miss events.\n");
@@ -411,10 +418,10 @@ static void __ref leave_uniprocessor(void)
int cpu;
int err;

- if (cpus_weight(downed_cpus) == 0)
+ if (downed_cpus == NULL || cpumask_weight(downed_cpus) == 0)
return;
pr_notice(NAME "Re-enabling CPUs...\n");
- for_each_cpu_mask(cpu, downed_cpus) {
+ for_each_cpu(cpu, downed_cpus) {
err = cpu_up(cpu);
if (!err)
pr_info(NAME "enabled CPU%d.\n", cpu);