2021-02-23 12:51:16

by Álvaro Fernández Rojas

Subject: [PATCH] mips: smp-bmips: fix CPU mappings

When booting bmips with SMP enabled on a BCM6358 running on CPU #1 instead of
CPU #0, the current CPU mapping code produces the following:
- smp_processor_id(): 0
- cpu_logical_map(): 1
- cpu_number_map(): 1

This is because SMP isn't supported on BCM6358 since it has a shared TLB, so
it is disabled and max_cpus is decreased from 2 to 1.

Signed-off-by: Álvaro Fernández Rojas <[email protected]>
---
arch/mips/kernel/smp-bmips.c | 27 +++++++++++++++++----------
1 file changed, 17 insertions(+), 10 deletions(-)

diff --git a/arch/mips/kernel/smp-bmips.c b/arch/mips/kernel/smp-bmips.c
index 359b176b665f..c4760cb48a67 100644
--- a/arch/mips/kernel/smp-bmips.c
+++ b/arch/mips/kernel/smp-bmips.c
@@ -134,17 +134,24 @@ static void __init bmips_smp_setup(void)
if (!board_ebase_setup)
board_ebase_setup = &bmips_ebase_setup;

- __cpu_number_map[boot_cpu] = 0;
- __cpu_logical_map[0] = boot_cpu;
-
- for (i = 0; i < max_cpus; i++) {
- if (i != boot_cpu) {
- __cpu_number_map[i] = cpu;
- __cpu_logical_map[cpu] = i;
- cpu++;
+ if (max_cpus > 1) {
+ __cpu_number_map[boot_cpu] = 0;
+ __cpu_logical_map[0] = boot_cpu;
+
+ for (i = 0; i < max_cpus; i++) {
+ if (i != boot_cpu) {
+ __cpu_number_map[i] = cpu;
+ __cpu_logical_map[cpu] = i;
+ cpu++;
+ }
+ set_cpu_possible(i, 1);
+ set_cpu_present(i, 1);
}
- set_cpu_possible(i, 1);
- set_cpu_present(i, 1);
+ } else {
+ __cpu_number_map[0] = boot_cpu;
+ __cpu_logical_map[0] = 0;
+ set_cpu_possible(0, 1);
+ set_cpu_possible(0, 1);
}
}

--
2.20.1

2021-02-24 07:21:44

by Florian Fainelli

Subject: Re: [PATCH] mips: smp-bmips: fix CPU mappings

On 2/23/2021 4:48 AM, Álvaro Fernández Rojas wrote:
> When booting bmips with SMP enabled on a BCM6358 running on CPU #1 instead of
> CPU #0, the current CPU mapping code produces the following:
> - smp_processor_id(): 0
> - cpu_logical_map(): 1
> - cpu_number_map(): 1
>
> This is because SMP isn't supported on BCM6358 since it has a shared TLB, so
> it is disabled and max_cpus is decreased from 2 to 1.
>
> Signed-off-by: Álvaro Fernández Rojas <[email protected]>
> ---
> arch/mips/kernel/smp-bmips.c | 27 +++++++++++++++++----------
> 1 file changed, 17 insertions(+), 10 deletions(-)
>
> diff --git a/arch/mips/kernel/smp-bmips.c b/arch/mips/kernel/smp-bmips.c
> index 359b176b665f..c4760cb48a67 100644
> --- a/arch/mips/kernel/smp-bmips.c
> +++ b/arch/mips/kernel/smp-bmips.c
> @@ -134,17 +134,24 @@ static void __init bmips_smp_setup(void)
> if (!board_ebase_setup)
> board_ebase_setup = &bmips_ebase_setup;
>
> - __cpu_number_map[boot_cpu] = 0;
> - __cpu_logical_map[0] = boot_cpu;
> -
> - for (i = 0; i < max_cpus; i++) {
> - if (i != boot_cpu) {
> - __cpu_number_map[i] = cpu;
> - __cpu_logical_map[cpu] = i;
> - cpu++;
> + if (max_cpus > 1) {
> + __cpu_number_map[boot_cpu] = 0;
> + __cpu_logical_map[0] = boot_cpu;
> +
> + for (i = 0; i < max_cpus; i++) {
> + if (i != boot_cpu) {
> + __cpu_number_map[i] = cpu;
> + __cpu_logical_map[cpu] = i;
> + cpu++;
> + }
> + set_cpu_possible(i, 1);
> + set_cpu_present(i, 1);
> }
> - set_cpu_possible(i, 1);
> - set_cpu_present(i, 1);
> + } else {
> + __cpu_number_map[0] = boot_cpu;
> + __cpu_logical_map[0] = 0;
> + set_cpu_possible(0, 1);
> + set_cpu_possible(0, 1);

Duplicate line, with that fixed:

Reviewed-by: Florian Fainelli <[email protected]>
--
Florian

2021-02-24 08:12:53

by Álvaro Fernández Rojas

Subject: Re: [PATCH] mips: smp-bmips: fix CPU mappings

Hi Florian,

> El 24 feb 2021, a las 4:45, Florian Fainelli <[email protected]> escribió:
>
>
>
> On 2/23/2021 4:48 AM, Álvaro Fernández Rojas wrote:
>> When booting bmips with SMP enabled on a BCM6358 running on CPU #1 instead of
>> CPU #0, the current CPU mapping code produces the following:
>> - smp_processor_id(): 0
>> - cpu_logical_map(): 1
>> - cpu_number_map(): 1
>>
>> This is because SMP isn't supported on BCM6358 since it has a shared TLB, so
>> it is disabled and max_cpus is decreased from 2 to 1.
>>
>> Signed-off-by: Álvaro Fernández Rojas <[email protected]>
>> ---
>> arch/mips/kernel/smp-bmips.c | 27 +++++++++++++++++----------
>> 1 file changed, 17 insertions(+), 10 deletions(-)
>>
>> diff --git a/arch/mips/kernel/smp-bmips.c b/arch/mips/kernel/smp-bmips.c
>> index 359b176b665f..c4760cb48a67 100644
>> --- a/arch/mips/kernel/smp-bmips.c
>> +++ b/arch/mips/kernel/smp-bmips.c
>> @@ -134,17 +134,24 @@ static void __init bmips_smp_setup(void)
>> if (!board_ebase_setup)
>> board_ebase_setup = &bmips_ebase_setup;
>>
>> - __cpu_number_map[boot_cpu] = 0;
>> - __cpu_logical_map[0] = boot_cpu;
>> -
>> - for (i = 0; i < max_cpus; i++) {
>> - if (i != boot_cpu) {
>> - __cpu_number_map[i] = cpu;
>> - __cpu_logical_map[cpu] = i;
>> - cpu++;
>> + if (max_cpus > 1) {
>> + __cpu_number_map[boot_cpu] = 0;
>> + __cpu_logical_map[0] = boot_cpu;
>> +
>> + for (i = 0; i < max_cpus; i++) {
>> + if (i != boot_cpu) {
>> + __cpu_number_map[i] = cpu;
>> + __cpu_logical_map[cpu] = i;
>> + cpu++;
>> + }
>> + set_cpu_possible(i, 1);
>> + set_cpu_present(i, 1);
>> }
>> - set_cpu_possible(i, 1);
>> - set_cpu_present(i, 1);
>> + } else {
>> + __cpu_number_map[0] = boot_cpu;
>> + __cpu_logical_map[0] = 0;
>> + set_cpu_possible(0, 1);
>> + set_cpu_possible(0, 1);
>
> Duplicate line, with that fixed:

Nice catch, it should be set_cpu_present().

>
> Reviewed-by: Florian Fainelli <[email protected]>
> --
> Florian

2021-02-24 08:21:57

by Álvaro Fernández Rojas

Subject: [PATCH v2] mips: smp-bmips: fix CPU mappings

When booting bmips with SMP enabled on a BCM6358 running on CPU #1 instead of
CPU #0, the current CPU mapping code produces the following:
- smp_processor_id(): 0
- cpu_logical_map(0): 1
- cpu_number_map(0): 1

This is because SMP isn't supported on BCM6358 since it has a shared TLB, so
it is disabled and max_cpus is decreased from 2 to 1.

Signed-off-by: Álvaro Fernández Rojas <[email protected]>
Reviewed-by: Florian Fainelli <[email protected]>
---
v2: Fix duplicated line

arch/mips/kernel/smp-bmips.c | 27 +++++++++++++++++----------
1 file changed, 17 insertions(+), 10 deletions(-)

diff --git a/arch/mips/kernel/smp-bmips.c b/arch/mips/kernel/smp-bmips.c
index 359b176b665f..b6ef5f7312cf 100644
--- a/arch/mips/kernel/smp-bmips.c
+++ b/arch/mips/kernel/smp-bmips.c
@@ -134,17 +134,24 @@ static void __init bmips_smp_setup(void)
if (!board_ebase_setup)
board_ebase_setup = &bmips_ebase_setup;

- __cpu_number_map[boot_cpu] = 0;
- __cpu_logical_map[0] = boot_cpu;
-
- for (i = 0; i < max_cpus; i++) {
- if (i != boot_cpu) {
- __cpu_number_map[i] = cpu;
- __cpu_logical_map[cpu] = i;
- cpu++;
+ if (max_cpus > 1) {
+ __cpu_number_map[boot_cpu] = 0;
+ __cpu_logical_map[0] = boot_cpu;
+
+ for (i = 0; i < max_cpus; i++) {
+ if (i != boot_cpu) {
+ __cpu_number_map[i] = cpu;
+ __cpu_logical_map[cpu] = i;
+ cpu++;
+ }
+ set_cpu_possible(i, 1);
+ set_cpu_present(i, 1);
}
- set_cpu_possible(i, 1);
- set_cpu_present(i, 1);
+ } else {
+ __cpu_number_map[0] = boot_cpu;
+ __cpu_logical_map[0] = 0;
+ set_cpu_possible(0, 1);
+ set_cpu_present(0, 1);
}
}

--
2.20.1

2021-02-27 06:50:10

by Álvaro Fernández Rojas

Subject: Re: [PATCH v2] mips: smp-bmips: fix CPU mappings

Hi all,

Apparently, this patch was flagged as "Not Applicable" without an explanation. Why?
https://patchwork.kernel.org/project/linux-mips/patch/[email protected]/

Best regarss,
Álvaro.

> El 24 feb 2021, a las 8:33, Álvaro Fernández Rojas <[email protected]> escribió:
>
> When booting bmips with SMP enabled on a BCM6358 running on CPU #1 instead of
> CPU #0, the current CPU mapping code produces the following:
> - smp_processor_id(): 0
> - cpu_logical_map(0): 1
> - cpu_number_map(0): 1
>
> This is because SMP isn't supported on BCM6358 since it has a shared TLB, so
> it is disabled and max_cpus is decreased from 2 to 1.
>
> Signed-off-by: Álvaro Fernández Rojas <[email protected]>
> Reviewed-by: Florian Fainelli <[email protected]>
> ---
> v2: Fix duplicated line
>
> arch/mips/kernel/smp-bmips.c | 27 +++++++++++++++++----------
> 1 file changed, 17 insertions(+), 10 deletions(-)
>
> diff --git a/arch/mips/kernel/smp-bmips.c b/arch/mips/kernel/smp-bmips.c
> index 359b176b665f..b6ef5f7312cf 100644
> --- a/arch/mips/kernel/smp-bmips.c
> +++ b/arch/mips/kernel/smp-bmips.c
> @@ -134,17 +134,24 @@ static void __init bmips_smp_setup(void)
> if (!board_ebase_setup)
> board_ebase_setup = &bmips_ebase_setup;
>
> - __cpu_number_map[boot_cpu] = 0;
> - __cpu_logical_map[0] = boot_cpu;
> -
> - for (i = 0; i < max_cpus; i++) {
> - if (i != boot_cpu) {
> - __cpu_number_map[i] = cpu;
> - __cpu_logical_map[cpu] = i;
> - cpu++;
> + if (max_cpus > 1) {
> + __cpu_number_map[boot_cpu] = 0;
> + __cpu_logical_map[0] = boot_cpu;
> +
> + for (i = 0; i < max_cpus; i++) {
> + if (i != boot_cpu) {
> + __cpu_number_map[i] = cpu;
> + __cpu_logical_map[cpu] = i;
> + cpu++;
> + }
> + set_cpu_possible(i, 1);
> + set_cpu_present(i, 1);
> }
> - set_cpu_possible(i, 1);
> - set_cpu_present(i, 1);
> + } else {
> + __cpu_number_map[0] = boot_cpu;
> + __cpu_logical_map[0] = 0;
> + set_cpu_possible(0, 1);
> + set_cpu_present(0, 1);
> }
> }
>
> --
> 2.20.1
>

2021-03-01 13:54:20

by Thomas Bogendoerfer

Subject: Re: [PATCH v2] mips: smp-bmips: fix CPU mappings

On Sat, Feb 27, 2021 at 07:47:42AM +0100, ?lvaro Fern?ndez Rojas wrote:
> Hi all,
>
> Apparently, this patch was flagged as "Not Applicable" without an
> explanation. Why?

hmm, I probaly wanted to drop the first version, but changed v2. It's
back to new again and I'm gogin to apply it soon.

Sorry about that.

Thomas.

--
Crap can work. Given enough thrust pigs will fly, but it's not necessarily a
good idea. [ RFC1925, 2.3 ]

2021-03-03 04:25:19

by Thomas Bogendoerfer

Subject: Re: [PATCH v2] mips: smp-bmips: fix CPU mappings

On Wed, Feb 24, 2021 at 08:33:36AM +0100, ?lvaro Fern?ndez Rojas wrote:
> When booting bmips with SMP enabled on a BCM6358 running on CPU #1 instead of
> CPU #0, the current CPU mapping code produces the following:
> - smp_processor_id(): 0
> - cpu_logical_map(0): 1
> - cpu_number_map(0): 1
>
> This is because SMP isn't supported on BCM6358 since it has a shared TLB, so
> it is disabled and max_cpus is decreased from 2 to 1.
>
> Signed-off-by: ?lvaro Fern?ndez Rojas <[email protected]>
> Reviewed-by: Florian Fainelli <[email protected]>
> ---
> v2: Fix duplicated line
>
> arch/mips/kernel/smp-bmips.c | 27 +++++++++++++++++----------
> 1 file changed, 17 insertions(+), 10 deletions(-)

applied to mips-next.

Thomas.

--
Crap can work. Given enough thrust pigs will fly, but it's not necessarily a
good idea. [ RFC1925, 2.3 ]