[PATCH] openrisc: use device tree to determine present cpus

[PATCH] openrisc: use device tree to determine present cpus

[Jan Henrik Weinstock]

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This patch proposes to use the device tree to determine the present cpus 
instead of assuming all CONFIG_NRCPUS are actually present in the system.

Signed-off-by: Jan Henrik Weinstock <jan.weinstock@rwth-aachen.de>
---
  arch/openrisc/kernel/smp.c | 18 +++++++++++++++---
  1 file changed, 15 insertions(+), 3 deletions(-)

diff --git a/arch/openrisc/kernel/smp.c b/arch/openrisc/kernel/smp.c
index 29c82ef2e..75be7e34f 100644
--- a/arch/openrisc/kernel/smp.c
+++ b/arch/openrisc/kernel/smp.c
@@ -16,6 +16,7 @@
  #include <linux/sched.h>
  #include <linux/sched/mm.h>
  #include <linux/irq.h>
+#include <linux/of.h>
  #include <asm/cpuinfo.h>
  #include <asm/mmu_context.h>
  #include <asm/tlbflush.h>
@@ -68,14 +69,25 @@ void __init smp_init_cpus(void)

  void __init smp_prepare_cpus(unsigned int max_cpus)
  {
-	int i;
+	u32 cpu_id;
+	struct device_node *cpu, *cpus;

  	/*
  	 * Initialise the present map, which describes the set of CPUs
  	 * actually populated at the present time.
  	 */
-	for (i = 0; i < max_cpus; i++)
-		set_cpu_present(i, true);
+	cpus = of_find_node_by_path("/cpus");
+	for_each_child_of_node(cpus, cpu) {
+		if (of_property_read_u32(cpu, "reg", &cpu_id)) {
+			pr_warn("%s missing reg property", cpu->full_name);
+			continue;
+		}
+
+		if (cpu_id >= max_cpus)
+			continue;
+
+		set_cpu_present(cpu_id, true);
+	}
  }

  void __init smp_cpus_done(unsigned int max_cpus)
-- 
2.17.1


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Re: [PATCH] openrisc: use device tree to determine present cpus

[Stafford Horne]

On Fri, Jan 29, 2021 at 07:29:31PM +0100, Jan Henrik Weinstock wrote:
> This patch proposes to use the device tree to determine the present cpus
> instead of assuming all CONFIG_NRCPUS are actually present in the system.
> 
> Signed-off-by: Jan Henrik Weinstock <jan.weinstock@rwth-aachen.de>
> ---
>  arch/openrisc/kernel/smp.c | 18 +++++++++++++++---
>  1 file changed, 15 insertions(+), 3 deletions(-)
> 
> diff --git a/arch/openrisc/kernel/smp.c b/arch/openrisc/kernel/smp.c
> index 29c82ef2e..75be7e34f 100644
> --- a/arch/openrisc/kernel/smp.c
> +++ b/arch/openrisc/kernel/smp.c
> @@ -16,6 +16,7 @@
>  #include <linux/sched.h>
>  #include <linux/sched/mm.h>
>  #include <linux/irq.h>
> +#include <linux/of.h>
>  #include <asm/cpuinfo.h>
>  #include <asm/mmu_context.h>
>  #include <asm/tlbflush.h>
> @@ -68,14 +69,25 @@ void __init smp_init_cpus(void)
> 
>  void __init smp_prepare_cpus(unsigned int max_cpus)
>  {
> -	int i;
> +	u32 cpu_id;
> +	struct device_node *cpu, *cpus;
> 
>  	/*
>  	 * Initialise the present map, which describes the set of CPUs
>  	 * actually populated at the present time.
>  	 */
> -	for (i = 0; i < max_cpus; i++)
> -		set_cpu_present(i, true);
> +	cpus = of_find_node_by_path("/cpus");
> +	for_each_child_of_node(cpus, cpu) {
> +		if (of_property_read_u32(cpu, "reg", &cpu_id)) {
> +			pr_warn("%s missing reg property", cpu->full_name);
> +			continue;
> +		}
> +
> +		if (cpu_id >= max_cpus)
> +			continue;
> +
> +		set_cpu_present(cpu_id, true);
> +	}

Hello, I looked into what other architectures do.  Risc-V does something similar
but it does the setup in 2 parts:

 - it uses the device tree to set possible CPU's in setup_smp. Using
   for_each_of_cpu_node and set_cpu_possible.

 - Then in smp_prepare_cpus, it loops over possible cpus with
   for_each_possible_cpu.

Note, it seems risc-v does't actually check max_cpus when setting
set_cpu_present which may be a bug.

I think the two part approach is what we want to do:

 - we should do set_cpu_possible in smp_init_cpus based on device tree.
   Basically the same as your loop above but using for_each_of_cpu_node
   and NR_CPUS.
 - we can then do set_cpu_present using for_each_possible_cpu in
   smp_prepare_cpus.

What do you think?

-Stafford

>  }
> 
>  void __init smp_cpus_done(unsigned int max_cpus)
> -- 
> 2.17.1
> 

Re: [PATCH] openrisc: use device tree to determine present cpus

[Jan Henrik Weinstock]

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Hi Stafford, Geert,

thanks for your feedback. I have made the following changes to the patch:

1. use for_each_of_cpu_node
2. possible_cpus is now what is in the devicetree, up to NR_CPUS
3. present_cpus is now all possible cpus, up to max_cpus

Signed-off-by: Jan Henrik Weinstock <jan.weinstock@rwth-aachen.de>
---
  arch/openrisc/kernel/smp.c | 23 +++++++++++++++++------
  1 file changed, 17 insertions(+), 6 deletions(-)

diff --git a/arch/openrisc/kernel/smp.c b/arch/openrisc/kernel/smp.c
index 29c82ef2e..83cbf43d4 100644
--- a/arch/openrisc/kernel/smp.c
+++ b/arch/openrisc/kernel/smp.c
@@ -16,6 +16,7 @@
  #include <linux/sched.h>
  #include <linux/sched/mm.h>
  #include <linux/irq.h>
+#include <linux/of.h>
  #include <asm/cpuinfo.h>
  #include <asm/mmu_context.h>
  #include <asm/tlbflush.h>
@@ -60,22 +61,32 @@ void __init smp_prepare_boot_cpu(void)

  void __init smp_init_cpus(void)
  {
-	int i;
+	struct device_node* cpu;
+	u32 cpu_id;

-	for (i = 0; i < NR_CPUS; i++)
-		set_cpu_possible(i, true);
+	for_each_of_cpu_node(cpu) {
+		if (of_property_read_u32(cpu, "reg", &cpu_id)) {
+			pr_warn("%s missing reg property", cpu->full_name);
+			continue;
+		}
+
+		if (cpu_id < NR_CPUS)
+			set_cpu_possible(cpu_id, true);
+	}
  }

  void __init smp_prepare_cpus(unsigned int max_cpus)
  {
-	int i;
+	unsigned int cpu;

  	/*
  	 * Initialise the present map, which describes the set of CPUs
  	 * actually populated at the present time.
  	 */
-	for (i = 0; i < max_cpus; i++)
-		set_cpu_present(i, true);
+	for_each_possible_cpu(cpu) {
+		if (cpu < max_cpus)
+			set_cpu_present(cpu, true);
+	}
  }

  void __init smp_cpus_done(unsigned int max_cpus)
-- 
2.17.1



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Re: [PATCH] openrisc: use device tree to determine present cpus

[Stafford Horne]

On Sat, Jan 30, 2021 at 12:00:10PM +0100, Jan Henrik Weinstock wrote:
> Hi Stafford, Geert,
> 
> thanks for your feedback. I have made the following changes to the patch:

Hi, Thanks for the updates.

> 1. use for_each_of_cpu_node
> 2. possible_cpus is now what is in the devicetree, up to NR_CPUS
> 3. present_cpus is now all possible cpus, up to max_cpus

This looks good, one small comment below.  Can you send the next patch as a v2?

Using 'git format-patch -v2 ...'

> Signed-off-by: Jan Henrik Weinstock <jan.weinstock@rwth-aachen.de>
> ---
You can include the 'Changes since v1' in the space here after '---'.

>  arch/openrisc/kernel/smp.c | 23 +++++++++++++++++------
>  1 file changed, 17 insertions(+), 6 deletions(-)
> 
> diff --git a/arch/openrisc/kernel/smp.c b/arch/openrisc/kernel/smp.c
> index 29c82ef2e..83cbf43d4 100644
> --- a/arch/openrisc/kernel/smp.c
> +++ b/arch/openrisc/kernel/smp.c
> @@ -16,6 +16,7 @@
>  #include <linux/sched.h>
>  #include <linux/sched/mm.h>
>  #include <linux/irq.h>
> +#include <linux/of.h>
>  #include <asm/cpuinfo.h>
>  #include <asm/mmu_context.h>
>  #include <asm/tlbflush.h>
> @@ -60,22 +61,32 @@ void __init smp_prepare_boot_cpu(void)
> 
>  void __init smp_init_cpus(void)
>  {
> -	int i;
> +	struct device_node* cpu;
> +	u32 cpu_id;
> 
> -	for (i = 0; i < NR_CPUS; i++)
> -		set_cpu_possible(i, true);
> +	for_each_of_cpu_node(cpu) {
> +		if (of_property_read_u32(cpu, "reg", &cpu_id)) {
> +			pr_warn("%s missing reg property", cpu->full_name);
> +			continue;
> +		}
> +
> +		if (cpu_id < NR_CPUS)

Should we warn on the else case?

> +			set_cpu_possible(cpu_id, true);
> +	}
>  }

-Stafford

Re: [PATCH] openrisc: use device tree to determine present cpus

[Stafford Horne]

Sorry, Please disrecard the g@lianli.shorne-pla.net address in the mail
distribution list.  I must have it a incorrect button.

 -Stafford

Re: [PATCH] openrisc: use device tree to determine present cpus

[Jan Henrik Weinstock]

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On 31/01/2021 00:03, Stafford Horne wrote:

> This looks good, one small comment below.  Can you send the next patch as a v2?
> 
> Using 'git format-patch -v2 ...'

Sorry, was not aware of that, will do better next time!

> Should we warn on the else case?

I think it is fine for the kernel to have room for more CPUs than are 
actually present (i.e. NR_CPUs > present_cpus is OK). Other Archs do not 
show a warning in this case either, therefore I also omitted it.

Gruss
Jan


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Re: [PATCH] openrisc: use device tree to determine present cpus

[Stafford Horne]

On Sun, Jan 31, 2021 at 09:22:31AM +0100, Jan Henrik Weinstock wrote:
> On 31/01/2021 00:03, Stafford Horne wrote:
> 
> > This looks good, one small comment below.  Can you send the next patch as a v2?
> > 
> > Using 'git format-patch -v2 ...'
> 
> Sorry, was not aware of that, will do better next time!
> 
> > Should we warn on the else case?
> 
> I think it is fine for the kernel to have room for more CPUs than are
> actually present (i.e. NR_CPUs > present_cpus is OK). Other Archs do not
> show a warning in this case either, therefore I also omitted it.

Fair enough.

Reviewed-by: Stafford Horne <shorne@gmail.com>

I can queue this for 5.12 when you send v2.

-Stafford

[PATCH v2] openrisc: use device tree to determine present cpus

[Jan Henrik Weinstock]

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Use the device tree to determine the present cpus instead of assuming 
all CONFIG_NRCPUS are actually present in the system.

Signed-off-by: Jan Henrik Weinstock <jan.weinstock@rwth-aachen.de>
---
Changes since v1:
  1. use for_each_of_cpu_node
  2. possible_cpus is now what is in the devicetree, up to NR_CPUS
  3. present_cpus is now all possible cpus, up to max_cpus

  arch/openrisc/kernel/smp.c | 31 +++++++++++++++----------------
  1 file changed, 15 insertions(+), 16 deletions(-)

diff --git a/arch/openrisc/kernel/smp.c b/arch/openrisc/kernel/smp.c
index 75be7e34f..83cbf43d4 100644
--- a/arch/openrisc/kernel/smp.c
+++ b/arch/openrisc/kernel/smp.c
@@ -61,32 +61,31 @@ void __init smp_prepare_boot_cpu(void)

  void __init smp_init_cpus(void)
  {
-	int i;
+	struct device_node* cpu;
+	u32 cpu_id;
+
+	for_each_of_cpu_node(cpu) {
+		if (of_property_read_u32(cpu, "reg", &cpu_id)) {
+			pr_warn("%s missing reg property", cpu->full_name);
+			continue;
+		}

-	for (i = 0; i < NR_CPUS; i++)
-		set_cpu_possible(i, true);
+		if (cpu_id < NR_CPUS)
+			set_cpu_possible(cpu_id, true);
+	}
  }

  void __init smp_prepare_cpus(unsigned int max_cpus)
  {
-	u32 cpu_id;
-	struct device_node *cpu, *cpus;
+	unsigned int cpu;

  	/*
  	 * Initialise the present map, which describes the set of CPUs
  	 * actually populated at the present time.
  	 */
-	cpus = of_find_node_by_path("/cpus");
-	for_each_child_of_node(cpus, cpu) {
-		if (of_property_read_u32(cpu, "reg", &cpu_id)) {
-			pr_warn("%s missing reg property", cpu->full_name);
-			continue;
-		}
-
-		if (cpu_id >= max_cpus)
-			continue;
-
-		set_cpu_present(cpu_id, true);
+	for_each_possible_cpu(cpu) {
+		if (cpu < max_cpus)
+			set_cpu_present(cpu, true);
  	}
  }

-- 
2.17.1


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Re: [PATCH v2] openrisc: use device tree to determine present cpus

[Stafford Horne]

On Mon, Feb 01, 2021 at 12:49:31PM +0100, Jan Henrik Weinstock wrote:
> Use the device tree to determine the present cpus instead of assuming all
> CONFIG_NRCPUS are actually present in the system.
> 
> Signed-off-by: Jan Henrik Weinstock <jan.weinstock@rwth-aachen.de>

Hi Jan,

I cannot apply this patch, it seems you somehow sent it signed as a multipart
message via Thunderbird.

This causes errors when trying to apply, even after I tried to manually fix the
patch mail:

    Applying: openrisc: use device tree to determine present cpus
    error: sha1 information is lacking or useless (arch/openrisc/kernel/smp.c).
    error: could not build fake ancestor
    Patch failed at 0001 openrisc: use device tree to determine present cpus

Can you send this using 'git send-email?'

If not I can get it applied with some work, otherwise you can point me to a git
repo which I can pull it from.

-Stafford

Re: [PATCH v2] openrisc: use device tree to determine present cpus

[Geert Uytterhoeven]

Hi Stafford,

On Fri, Feb 5, 2021 at 3:43 PM Stafford Horne <shorne@gmail.com> wrote:
> On Mon, Feb 01, 2021 at 12:49:31PM +0100, Jan Henrik Weinstock wrote:
> > Use the device tree to determine the present cpus instead of assuming all
> > CONFIG_NRCPUS are actually present in the system.
> >
> > Signed-off-by: Jan Henrik Weinstock <jan.weinstock@rwth-aachen.de>
>
> Hi Jan,
>
> I cannot apply this patch, it seems you somehow sent it signed as a multipart
> message via Thunderbird.
>
> This causes errors when trying to apply, even after I tried to manually fix the
> patch mail:
>
>     Applying: openrisc: use device tree to determine present cpus
>     error: sha1 information is lacking or useless (arch/openrisc/kernel/smp.c).
>     error: could not build fake ancestor
>     Patch failed at 0001 openrisc: use device tree to determine present cpus
>
> Can you send this using 'git send-email?'
>
> If not I can get it applied with some work, otherwise you can point me to a git
> repo which I can pull it from.

"b4 am 6dbc27f8-5261-59c5-acba-70f6c6a74ba1@rwth-aachen.de" works
fine for me.

git://git.kernel.org/pub/scm/utils/b4/b4.git

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH v2] openrisc: use device tree to determine present cpus

[Stafford Horne]

On Fri, Feb 05, 2021 at 05:07:51PM +0100, Geert Uytterhoeven wrote:
> Hi Stafford,
> 
> On Fri, Feb 5, 2021 at 3:43 PM Stafford Horne <shorne@gmail.com> wrote:
> > On Mon, Feb 01, 2021 at 12:49:31PM +0100, Jan Henrik Weinstock wrote:
> > > Use the device tree to determine the present cpus instead of assuming all
> > > CONFIG_NRCPUS are actually present in the system.
> > >
> > > Signed-off-by: Jan Henrik Weinstock <jan.weinstock@rwth-aachen.de>
> >
> > Hi Jan,
> >
> > I cannot apply this patch, it seems you somehow sent it signed as a multipart
> > message via Thunderbird.
> >
> > This causes errors when trying to apply, even after I tried to manually fix the
> > patch mail:
> >
> >     Applying: openrisc: use device tree to determine present cpus
> >     error: sha1 information is lacking or useless (arch/openrisc/kernel/smp.c).
> >     error: could not build fake ancestor
> >     Patch failed at 0001 openrisc: use device tree to determine present cpus
> >
> > Can you send this using 'git send-email?'
> >
> > If not I can get it applied with some work, otherwise you can point me to a git
> > repo which I can pull it from.
> 
> "b4 am 6dbc27f8-5261-59c5-acba-70f6c6a74ba1@rwth-aachen.de" works
> fine for me.
> 
> git://git.kernel.org/pub/scm/utils/b4/b4.git

Did it work?  For me I got, base not found.

    Looking up
    https://lore.kernel.org/r/6dbc27f8-5261-59c5-acba-70f6c6a74ba1%40rwth-aachen.de
    Grabbing thread from lore.kernel.org/lkml
    Analyzing 9 messages in the thread
    Will use the latest revision: v2
    You can pick other revisions using the -vN flag
    ---
    Writing
    ./v2_20210201_jan_weinstock_openrisc_use_device_tree_to_determine_present_cpus.mbx
      [PATCH v2] openrisc: use device tree to determine present cpus
    ---
    Total patches: 1
    ---
     Link:
    https://lore.kernel.org/r/6dbc27f8-5261-59c5-acba-70f6c6a74ba1@rwth-aachen.de
     Base: not found
	   git am
    ./v2_20210201_jan_weinstock_openrisc_use_device_tree_to_determine_present_cpus.mbx

-Stafford

Re: [PATCH v2] openrisc: use device tree to determine present cpus

[Geert Uytterhoeven]

Hi Stafford,

On Fri, Feb 5, 2021 at 11:36 PM Stafford Horne <shorne@gmail.com> wrote:
> On Fri, Feb 05, 2021 at 05:07:51PM +0100, Geert Uytterhoeven wrote:
> > On Fri, Feb 5, 2021 at 3:43 PM Stafford Horne <shorne@gmail.com> wrote:
> > > On Mon, Feb 01, 2021 at 12:49:31PM +0100, Jan Henrik Weinstock wrote:
> > > > Use the device tree to determine the present cpus instead of assuming all
> > > > CONFIG_NRCPUS are actually present in the system.
> > > >
> > > > Signed-off-by: Jan Henrik Weinstock <jan.weinstock@rwth-aachen.de>
> > >
> > > I cannot apply this patch, it seems you somehow sent it signed as a multipart
> > > message via Thunderbird.
> > >
> > > This causes errors when trying to apply, even after I tried to manually fix the
> > > patch mail:
> > >
> > >     Applying: openrisc: use device tree to determine present cpus
> > >     error: sha1 information is lacking or useless (arch/openrisc/kernel/smp.c).
> > >     error: could not build fake ancestor
> > >     Patch failed at 0001 openrisc: use device tree to determine present cpus
> > >
> > > Can you send this using 'git send-email?'
> > >
> > > If not I can get it applied with some work, otherwise you can point me to a git
> > > repo which I can pull it from.
> >
> > "b4 am 6dbc27f8-5261-59c5-acba-70f6c6a74ba1@rwth-aachen.de" works
> > fine for me.
> >
> > git://git.kernel.org/pub/scm/utils/b4/b4.git
>
> Did it work?  For me I got, base not found.
>
>     Looking up
>     https://lore.kernel.org/r/6dbc27f8-5261-59c5-acba-70f6c6a74ba1%40rwth-aachen.de
>     Grabbing thread from lore.kernel.org/lkml
>     Analyzing 9 messages in the thread
>     Will use the latest revision: v2
>     You can pick other revisions using the -vN flag
>     ---
>     Writing
>     ./v2_20210201_jan_weinstock_openrisc_use_device_tree_to_determine_present_cpus.mbx
>       [PATCH v2] openrisc: use device tree to determine present cpus
>     ---
>     Total patches: 1
>     ---
>      Link:
>     https://lore.kernel.org/r/6dbc27f8-5261-59c5-acba-70f6c6a74ba1@rwth-aachen.de
>      Base: not found

That just means the patch contains no information w.r.t. its base, i.e.
against which tree/commit it applies to.  To be ignored.

>            git am
>     ./v2_20210201_jan_weinstock_openrisc_use_device_tree_to_determine_present_cpus.mbx

Just run the above command ;-)

In addition, you can run "formail -s scripts/checkpatch.pl < *mbx" first, to
run the mbox (which could contain multiple patches) through checkpatch.


Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH v2] openrisc: use device tree to determine present cpus

[Geert Uytterhoeven]

Hi Stafford,

On Mon, Feb 8, 2021 at 1:16 PM Stafford Horne <shorne@gmail.com> wrote:
> On Sat, Feb 06, 2021 at 10:33:24AM +0100, Geert Uytterhoeven wrote:
> > On Fri, Feb 5, 2021 at 11:36 PM Stafford Horne <shorne@gmail.com> wrote:
> > > On Fri, Feb 05, 2021 at 05:07:51PM +0100, Geert Uytterhoeven wrote:
> > > > On Fri, Feb 5, 2021 at 3:43 PM Stafford Horne <shorne@gmail.com> wrote:
> > > > > On Mon, Feb 01, 2021 at 12:49:31PM +0100, Jan Henrik Weinstock wrote:
> > > > > > Use the device tree to determine the present cpus instead of assuming all
> > > > > > CONFIG_NRCPUS are actually present in the system.
> > > > > >
> > > > > > Signed-off-by: Jan Henrik Weinstock <jan.weinstock@rwth-aachen.de>
> > > > >
> > > > > I cannot apply this patch, it seems you somehow sent it signed as a multipart
> > > > > message via Thunderbird.
> > > > >
> > > > > This causes errors when trying to apply, even after I tried to manually fix the
> > > > > patch mail:
> > > > >
> > > > >     Applying: openrisc: use device tree to determine present cpus
> > > > >     error: sha1 information is lacking or useless (arch/openrisc/kernel/smp.c).
> > > > >     error: could not build fake ancestor
> > > > >     Patch failed at 0001 openrisc: use device tree to determine present cpus
> > > > >
> > > > > Can you send this using 'git send-email?'
> > > > >
> > > > > If not I can get it applied with some work, otherwise you can point me to a git
> > > > > repo which I can pull it from.
> > > >
> > > > "b4 am 6dbc27f8-5261-59c5-acba-70f6c6a74ba1@rwth-aachen.de" works
> > > > fine for me.
> > > >
> > > > git://git.kernel.org/pub/scm/utils/b4/b4.git
> > >
> > > Did it work?  For me I got, base not found.
> > >
> > >     Looking up
> > >     https://lore.kernel.org/r/6dbc27f8-5261-59c5-acba-70f6c6a74ba1%40rwth-aachen.de
> > >     Grabbing thread from lore.kernel.org/lkml
> > >     Analyzing 9 messages in the thread
> > >     Will use the latest revision: v2
> > >     You can pick other revisions using the -vN flag
> > >     ---
> > >     Writing
> > >     ./v2_20210201_jan_weinstock_openrisc_use_device_tree_to_determine_present_cpus.mbx
> > >       [PATCH v2] openrisc: use device tree to determine present cpus
> > >     ---
> > >     Total patches: 1
> > >     ---
> > >      Link:
> > >     https://lore.kernel.org/r/6dbc27f8-5261-59c5-acba-70f6c6a74ba1@rwth-aachen.de
> > >      Base: not found
> >
> > That just means the patch contains no information w.r.t. its base, i.e.
> > against which tree/commit it applies to.  To be ignored.
> >
> > >            git am
> > >     ./v2_20210201_jan_weinstock_openrisc_use_device_tree_to_determine_present_cpus.mbx
> >
> > Just run the above command ;-)
> >
> > In addition, you can run "formail -s scripts/checkpatch.pl < *mbx" first, to
> > run the mbox (which could contain multiple patches) through checkpatch.
>
> Thanks for your help, but this is still not working.  See that attached patch.
> If your patch doesn't have this corruption then please forward it.  If Jan could
> point to a git repo or reset with 'git send-email' that would be great too.
>
> It seems that the mailer has corrupted the patch by adding and removing
> whitespace to each line.
>
> I don't have a 'formail' command, but I did try 'git am' and 'checkpatch.pl' and
> it shows:
>
>     < shorne@lianli ~/work/linux > git am v2_20210201_jan_weinstock_openrisc_use_device_tree_to_determine_present_cpus.mbx
>     Applying: openrisc: use device tree to determine present cpus
>     error: corrupt patch at line 62

Indeed, the patch is corrupt.
Sorry for not verifying that before. I just thought you had an issue
saving multipart patches.

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH] openrisc: use device tree to determine present cpus

[Geert Uytterhoeven]

Hi Jan,

On Fri, Jan 29, 2021 at 7:34 PM Jan Henrik Weinstock
<jan.weinstock@rwth-aachen.de> wrote:
> This patch proposes to use the device tree to determine the present cpus
> instead of assuming all CONFIG_NRCPUS are actually present in the system.
>
> Signed-off-by: Jan Henrik Weinstock <jan.weinstock@rwth-aachen.de>

Thanks for your patch!

> --- a/arch/openrisc/kernel/smp.c
> +++ b/arch/openrisc/kernel/smp.c

> @@ -68,14 +69,25 @@ void __init smp_init_cpus(void)
>
>   void __init smp_prepare_cpus(unsigned int max_cpus)
>   {
> -       int i;
> +       u32 cpu_id;
> +       struct device_node *cpu, *cpus;
>
>         /*
>          * Initialise the present map, which describes the set of CPUs
>          * actually populated at the present time.
>          */
> -       for (i = 0; i < max_cpus; i++)
> -               set_cpu_present(i, true);
> +       cpus = of_find_node_by_path("/cpus");
> +       for_each_child_of_node(cpus, cpu) {

for_each_of_cpu_node()?

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds