Re: [PATCH 03/34] powerpc: Use CONFIG_PREEMPTION
On 2019-10-16 20:33:08 [+1100], Michael Ellerman wrote: > Christophe Leroy writes: > > Le 15/10/2019 à 21:17, Sebastian Andrzej Siewior a écrit : > >> From: Thomas Gleixner > >> > >> CONFIG_PREEMPTION is selected by CONFIG_PREEMPT and by CONFIG_PREEMPT_RT. > >> Both PREEMPT and PREEMPT_RT require the same functionality which today > >> depends on CONFIG_PREEMPT. > >> > >> Switch the entry code over to use CONFIG_PREEMPTION. Add PREEMPT_RT > >> output in __die(). > > > > powerpc doesn't select ARCH_SUPPORTS_RT, so this change is useless as > > CONFIG_PREEMPT_RT cannot be selected. > > Yeah I don't think there's any point adding the "_RT" to the __die() > output until/if we ever start supporting PREEMPT_RT. so jut the PREEMPT -> PREEMPTION bits then? > cheers Sebastian
Re: [PATCH 03/34] powerpc: Use CONFIG_PREEMPTION
Christophe Leroy writes:
> Le 15/10/2019 à 21:17, Sebastian Andrzej Siewior a écrit :
>> From: Thomas Gleixner
>>
>> CONFIG_PREEMPTION is selected by CONFIG_PREEMPT and by CONFIG_PREEMPT_RT.
>> Both PREEMPT and PREEMPT_RT require the same functionality which today
>> depends on CONFIG_PREEMPT.
>>
>> Switch the entry code over to use CONFIG_PREEMPTION. Add PREEMPT_RT
>> output in __die().
>
> powerpc doesn't select ARCH_SUPPORTS_RT, so this change is useless as
> CONFIG_PREEMPT_RT cannot be selected.
Yeah I don't think there's any point adding the "_RT" to the __die()
output until/if we ever start supporting PREEMPT_RT.
cheers
>> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
>> index 3e56c9c2f16ee..8ead8d6e1cbc8 100644
>> --- a/arch/powerpc/Kconfig
>> +++ b/arch/powerpc/Kconfig
>> @@ -106,7 +106,7 @@ config LOCKDEP_SUPPORT
>> config GENERIC_LOCKBREAK
>> bool
>> default y
>> -depends on SMP && PREEMPT
>> +depends on SMP && PREEMPTION
>>
>> config GENERIC_HWEIGHT
>> bool
>> diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
>> index d60908ea37fb9..e1a4c39b83b86 100644
>> --- a/arch/powerpc/kernel/entry_32.S
>> +++ b/arch/powerpc/kernel/entry_32.S
>> @@ -897,7 +897,7 @@ user_exc_return: /* r10 contains MSR_KERNEL here
>> */
>> bne-0b
>> 1:
>>
>> -#ifdef CONFIG_PREEMPT
>> +#ifdef CONFIG_PREEMPTION
>> /* check current_thread_info->preempt_count */
>> lwz r0,TI_PREEMPT(r2)
>> cmpwi 0,r0,0 /* if non-zero, just restore regs and return */
>> @@ -921,7 +921,7 @@ user_exc_return: /* r10 contains MSR_KERNEL here
>> */
>> */
>> bl trace_hardirqs_on
>> #endif
>> -#endif /* CONFIG_PREEMPT */
>> +#endif /* CONFIG_PREEMPTION */
>> restore_kuap:
>> kuap_restore r1, r2, r9, r10, r0
>>
>> diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
>> index 6467bdab8d405..83733376533e8 100644
>> --- a/arch/powerpc/kernel/entry_64.S
>> +++ b/arch/powerpc/kernel/entry_64.S
>> @@ -840,7 +840,7 @@ _GLOBAL(ret_from_except_lite)
>> bne-0b
>> 1:
>>
>> -#ifdef CONFIG_PREEMPT
>> +#ifdef CONFIG_PREEMPTION
>> /* Check if we need to preempt */
>> andi. r0,r4,_TIF_NEED_RESCHED
>> beq+restore
>> @@ -871,7 +871,7 @@ _GLOBAL(ret_from_except_lite)
>> li r10,MSR_RI
>> mtmsrd r10,1 /* Update machine state */
>> #endif /* CONFIG_PPC_BOOK3E */
>> -#endif /* CONFIG_PREEMPT */
>> +#endif /* CONFIG_PREEMPTION */
>>
>> .globl fast_exc_return_irq
>> fast_exc_return_irq:
>> diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
>> index 82f43535e6867..23d2f20be4f2e 100644
>> --- a/arch/powerpc/kernel/traps.c
>> +++ b/arch/powerpc/kernel/traps.c
>> @@ -252,14 +252,19 @@ NOKPROBE_SYMBOL(oops_end);
>>
>> static int __die(const char *str, struct pt_regs *regs, long err)
>> {
>> +const char *pr = "";
>> +
>
> Please follow the same approach as already existing. Don't add a local
> var for that.
>
>> printk("Oops: %s, sig: %ld [#%d]\n", str, err, ++die_counter);
>>
>> +if (IS_ENABLED(CONFIG_PREEMPTION))
>> +pr = IS_ENABLED(CONFIG_PREEMPT_RT) ? " PREEMPT_RT" : " PREEMPT";
>> +
>
> drop
>
>> printk("%s PAGE_SIZE=%luK%s%s%s%s%s%s%s %s\n",
>
> Add one %s
>
>> IS_ENABLED(CONFIG_CPU_LITTLE_ENDIAN) ? "LE" : "BE",
>> PAGE_SIZE / 1024,
>> early_radix_enabled() ? " MMU=Radix" : "",
>> early_mmu_has_feature(MMU_FTR_HPTE_TABLE) ? " MMU=Hash" : "",
>> - IS_ENABLED(CONFIG_PREEMPT) ? " PREEMPT" : "",
>
> Replace by: IS_ENABLED(CONFIG_PREEMPTION) ? " PREEMPT" : ""
>
>> + pr,
>
> add something like: IS_ENABLED(CONFIG_PREEMPT_RT) ? "_RT" : ""
>
>> IS_ENABLED(CONFIG_SMP) ? " SMP" : "",
>> IS_ENABLED(CONFIG_SMP) ? (" NR_CPUS=" __stringify(NR_CPUS)) : "",
>> debug_pagealloc_enabled() ? " DEBUG_PAGEALLOC" : "",
>>
>
> Christophe
Re: [PATCH 03/34] powerpc: Use CONFIG_PREEMPTION
On 2019-10-16 06:57:48 [+0200], Christophe Leroy wrote:
>
>
> Le 15/10/2019 à 21:17, Sebastian Andrzej Siewior a écrit :
> > From: Thomas Gleixner
> >
> > CONFIG_PREEMPTION is selected by CONFIG_PREEMPT and by CONFIG_PREEMPT_RT.
> > Both PREEMPT and PREEMPT_RT require the same functionality which today
> > depends on CONFIG_PREEMPT.
> >
> > Switch the entry code over to use CONFIG_PREEMPTION. Add PREEMPT_RT
> > output in __die().
>
> powerpc doesn't select ARCH_SUPPORTS_RT, so this change is useless as
> CONFIG_PREEMPT_RT cannot be selected.
No it is not. It makes it possible for PowerPC to select it one day and
I have patches for it today. Also, if other ARCH copies code from
PowerPC it will copy the correct thing (as in distinguish between the
flavour PREEMPT and the functionality PREEMPTION).
> > diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
> > index 82f43535e6867..23d2f20be4f2e 100644
> > --- a/arch/powerpc/kernel/traps.c
> > +++ b/arch/powerpc/kernel/traps.c
> > @@ -252,14 +252,19 @@ NOKPROBE_SYMBOL(oops_end);
> > static int __die(const char *str, struct pt_regs *regs, long err)
> > {
> > + const char *pr = "";
> > +
>
> Please follow the same approach as already existing. Don't add a local var
> for that.
I would leave it to the maintainer to comment on that and decide which
one they want. My eyes find it more readable and the compiles does not
create more code.
> > printk("Oops: %s, sig: %ld [#%d]\n", str, err, ++die_counter);
> > + if (IS_ENABLED(CONFIG_PREEMPTION))
> > + pr = IS_ENABLED(CONFIG_PREEMPT_RT) ? " PREEMPT_RT" : " PREEMPT";
> > +
>
> drop
>
> > printk("%s PAGE_SIZE=%luK%s%s%s%s%s%s%s %s\n",
>
> Add one %s
>
> >IS_ENABLED(CONFIG_CPU_LITTLE_ENDIAN) ? "LE" : "BE",
> >PAGE_SIZE / 1024,
> >early_radix_enabled() ? " MMU=Radix" : "",
> >early_mmu_has_feature(MMU_FTR_HPTE_TABLE) ? " MMU=Hash" : "",
> > - IS_ENABLED(CONFIG_PREEMPT) ? " PREEMPT" : "",
>
> Replace by: IS_ENABLED(CONFIG_PREEMPTION) ? " PREEMPT" : ""
>
> > + pr,
>
> add something like: IS_ENABLED(CONFIG_PREEMPT_RT) ? "_RT" : ""
this on the other hand will create more code which is not strictly
required.
> >IS_ENABLED(CONFIG_SMP) ? " SMP" : "",
> >IS_ENABLED(CONFIG_SMP) ? (" NR_CPUS=" __stringify(NR_CPUS)) : "",
> >debug_pagealloc_enabled() ? " DEBUG_PAGEALLOC" : "",
> >
>
> Christophe
Sebastian
Re: [PATCH 03/34] powerpc: Use CONFIG_PREEMPTION
Le 15/10/2019 à 21:17, Sebastian Andrzej Siewior a écrit :
From: Thomas Gleixner
CONFIG_PREEMPTION is selected by CONFIG_PREEMPT and by CONFIG_PREEMPT_RT.
Both PREEMPT and PREEMPT_RT require the same functionality which today
depends on CONFIG_PREEMPT.
Switch the entry code over to use CONFIG_PREEMPTION. Add PREEMPT_RT
output in __die().
powerpc doesn't select ARCH_SUPPORTS_RT, so this change is useless as
CONFIG_PREEMPT_RT cannot be selected.
Cc: Benjamin Herrenschmidt
Cc: Paul Mackerras
Cc: Michael Ellerman
Cc: linuxppc-...@lists.ozlabs.org
Signed-off-by: Thomas Gleixner
[bigeasy: +traps.c, Kconfig]
Signed-off-by: Sebastian Andrzej Siewior
---
arch/powerpc/Kconfig | 2 +-
arch/powerpc/kernel/entry_32.S | 4 ++--
arch/powerpc/kernel/entry_64.S | 4 ++--
arch/powerpc/kernel/traps.c| 7 ++-
4 files changed, 11 insertions(+), 6 deletions(-)
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 3e56c9c2f16ee..8ead8d6e1cbc8 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -106,7 +106,7 @@ config LOCKDEP_SUPPORT
config GENERIC_LOCKBREAK
bool
default y
- depends on SMP && PREEMPT
+ depends on SMP && PREEMPTION
config GENERIC_HWEIGHT
bool
diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index d60908ea37fb9..e1a4c39b83b86 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -897,7 +897,7 @@ user_exc_return:/* r10 contains MSR_KERNEL here
*/
bne-0b
1:
-#ifdef CONFIG_PREEMPT
+#ifdef CONFIG_PREEMPTION
/* check current_thread_info->preempt_count */
lwz r0,TI_PREEMPT(r2)
cmpwi 0,r0,0 /* if non-zero, just restore regs and return */
@@ -921,7 +921,7 @@ user_exc_return:/* r10 contains MSR_KERNEL here
*/
*/
bl trace_hardirqs_on
#endif
-#endif /* CONFIG_PREEMPT */
+#endif /* CONFIG_PREEMPTION */
restore_kuap:
kuap_restore r1, r2, r9, r10, r0
diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index 6467bdab8d405..83733376533e8 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -840,7 +840,7 @@ _GLOBAL(ret_from_except_lite)
bne-0b
1:
-#ifdef CONFIG_PREEMPT
+#ifdef CONFIG_PREEMPTION
/* Check if we need to preempt */
andi. r0,r4,_TIF_NEED_RESCHED
beq+restore
@@ -871,7 +871,7 @@ _GLOBAL(ret_from_except_lite)
li r10,MSR_RI
mtmsrd r10,1 /* Update machine state */
#endif /* CONFIG_PPC_BOOK3E */
-#endif /* CONFIG_PREEMPT */
+#endif /* CONFIG_PREEMPTION */
.globl fast_exc_return_irq
fast_exc_return_irq:
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index 82f43535e6867..23d2f20be4f2e 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c
@@ -252,14 +252,19 @@ NOKPROBE_SYMBOL(oops_end);
static int __die(const char *str, struct pt_regs *regs, long err)
{
+ const char *pr = "";
+
Please follow the same approach as already existing. Don't add a local
var for that.
printk("Oops: %s, sig: %ld [#%d]\n", str, err, ++die_counter);
+ if (IS_ENABLED(CONFIG_PREEMPTION))
+ pr = IS_ENABLED(CONFIG_PREEMPT_RT) ? " PREEMPT_RT" : " PREEMPT";
+
drop
printk("%s PAGE_SIZE=%luK%s%s%s%s%s%s%s %s\n",
Add one %s
IS_ENABLED(CONFIG_CPU_LITTLE_ENDIAN) ? "LE" : "BE",
PAGE_SIZE / 1024,
early_radix_enabled() ? " MMU=Radix" : "",
early_mmu_has_feature(MMU_FTR_HPTE_TABLE) ? " MMU=Hash" : "",
- IS_ENABLED(CONFIG_PREEMPT) ? " PREEMPT" : "",
Replace by: IS_ENABLED(CONFIG_PREEMPTION) ? " PREEMPT" : ""
+ pr,
add something like: IS_ENABLED(CONFIG_PREEMPT_RT) ? "_RT" : ""
IS_ENABLED(CONFIG_SMP) ? " SMP" : "",
IS_ENABLED(CONFIG_SMP) ? (" NR_CPUS=" __stringify(NR_CPUS)) : "",
debug_pagealloc_enabled() ? " DEBUG_PAGEALLOC" : "",
Christophe
[PATCH 03/34] powerpc: Use CONFIG_PREEMPTION
From: Thomas Gleixner
CONFIG_PREEMPTION is selected by CONFIG_PREEMPT and by CONFIG_PREEMPT_RT.
Both PREEMPT and PREEMPT_RT require the same functionality which today
depends on CONFIG_PREEMPT.
Switch the entry code over to use CONFIG_PREEMPTION. Add PREEMPT_RT
output in __die().
Cc: Benjamin Herrenschmidt
Cc: Paul Mackerras
Cc: Michael Ellerman
Cc: linuxppc-...@lists.ozlabs.org
Signed-off-by: Thomas Gleixner
[bigeasy: +traps.c, Kconfig]
Signed-off-by: Sebastian Andrzej Siewior
---
arch/powerpc/Kconfig | 2 +-
arch/powerpc/kernel/entry_32.S | 4 ++--
arch/powerpc/kernel/entry_64.S | 4 ++--
arch/powerpc/kernel/traps.c| 7 ++-
4 files changed, 11 insertions(+), 6 deletions(-)
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 3e56c9c2f16ee..8ead8d6e1cbc8 100644
--- a/arch/powerpc/Kconfig
+++ b/arch/powerpc/Kconfig
@@ -106,7 +106,7 @@ config LOCKDEP_SUPPORT
config GENERIC_LOCKBREAK
bool
default y
- depends on SMP && PREEMPT
+ depends on SMP && PREEMPTION
config GENERIC_HWEIGHT
bool
diff --git a/arch/powerpc/kernel/entry_32.S b/arch/powerpc/kernel/entry_32.S
index d60908ea37fb9..e1a4c39b83b86 100644
--- a/arch/powerpc/kernel/entry_32.S
+++ b/arch/powerpc/kernel/entry_32.S
@@ -897,7 +897,7 @@ user_exc_return:/* r10 contains MSR_KERNEL here
*/
bne-0b
1:
-#ifdef CONFIG_PREEMPT
+#ifdef CONFIG_PREEMPTION
/* check current_thread_info->preempt_count */
lwz r0,TI_PREEMPT(r2)
cmpwi 0,r0,0 /* if non-zero, just restore regs and return */
@@ -921,7 +921,7 @@ user_exc_return:/* r10 contains MSR_KERNEL here
*/
*/
bl trace_hardirqs_on
#endif
-#endif /* CONFIG_PREEMPT */
+#endif /* CONFIG_PREEMPTION */
restore_kuap:
kuap_restore r1, r2, r9, r10, r0
diff --git a/arch/powerpc/kernel/entry_64.S b/arch/powerpc/kernel/entry_64.S
index 6467bdab8d405..83733376533e8 100644
--- a/arch/powerpc/kernel/entry_64.S
+++ b/arch/powerpc/kernel/entry_64.S
@@ -840,7 +840,7 @@ _GLOBAL(ret_from_except_lite)
bne-0b
1:
-#ifdef CONFIG_PREEMPT
+#ifdef CONFIG_PREEMPTION
/* Check if we need to preempt */
andi. r0,r4,_TIF_NEED_RESCHED
beq+restore
@@ -871,7 +871,7 @@ _GLOBAL(ret_from_except_lite)
li r10,MSR_RI
mtmsrd r10,1 /* Update machine state */
#endif /* CONFIG_PPC_BOOK3E */
-#endif /* CONFIG_PREEMPT */
+#endif /* CONFIG_PREEMPTION */
.globl fast_exc_return_irq
fast_exc_return_irq:
diff --git a/arch/powerpc/kernel/traps.c b/arch/powerpc/kernel/traps.c
index 82f43535e6867..23d2f20be4f2e 100644
--- a/arch/powerpc/kernel/traps.c
+++ b/arch/powerpc/kernel/traps.c
@@ -252,14 +252,19 @@ NOKPROBE_SYMBOL(oops_end);
static int __die(const char *str, struct pt_regs *regs, long err)
{
+ const char *pr = "";
+
printk("Oops: %s, sig: %ld [#%d]\n", str, err, ++die_counter);
+ if (IS_ENABLED(CONFIG_PREEMPTION))
+ pr = IS_ENABLED(CONFIG_PREEMPT_RT) ? " PREEMPT_RT" : " PREEMPT";
+
printk("%s PAGE_SIZE=%luK%s%s%s%s%s%s%s %s\n",
IS_ENABLED(CONFIG_CPU_LITTLE_ENDIAN) ? "LE" : "BE",
PAGE_SIZE / 1024,
early_radix_enabled() ? " MMU=Radix" : "",
early_mmu_has_feature(MMU_FTR_HPTE_TABLE) ? " MMU=Hash" : "",
- IS_ENABLED(CONFIG_PREEMPT) ? " PREEMPT" : "",
+ pr,
IS_ENABLED(CONFIG_SMP) ? " SMP" : "",
IS_ENABLED(CONFIG_SMP) ? (" NR_CPUS=" __stringify(NR_CPUS)) : "",
debug_pagealloc_enabled() ? " DEBUG_PAGEALLOC" : "",
--
2.23.0
