| Message ID | 1371714797-7898-5-git-send-email-tiejun.chen@windriver.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
> -----Original Message----- > From: Linuxppc-dev [mailto:linuxppc-dev- > bounces+bharat.bhushan=freescale.com@lists.ozlabs.org] On Behalf Of Tiejun Chen > Sent: Thursday, June 20, 2013 1:23 PM > To: benh@kernel.crashing.org > Cc: linuxppc-dev@lists.ozlabs.org; linux-kernel@vger.kernel.org > Subject: [v2][PATCH 4/7] book3e/kexec/kdump: introduce a kexec kernel flag > > We need to introduce a flag to indicate we're already running > a kexec kernel then we can go proper path. For example, We > shouldn't access spin_table from the bootloader to up any secondary > cpu for kexec kernel, and kexec kernel already know how to jump to > generic_secondary_smp_init. > > Signed-off-by: Tiejun Chen <tiejun.chen@windriver.com> > --- > arch/powerpc/include/asm/smp.h | 3 +++ > arch/powerpc/kernel/head_64.S | 12 ++++++++++++ > arch/powerpc/kernel/misc_64.S | 6 ++++++ > arch/powerpc/platforms/85xx/smp.c | 14 ++++++++++++++ > 4 files changed, 35 insertions(+) > > diff --git a/arch/powerpc/include/asm/smp.h b/arch/powerpc/include/asm/smp.h > index ffbaabe..fbc3d9b 100644 > --- a/arch/powerpc/include/asm/smp.h > +++ b/arch/powerpc/include/asm/smp.h > @@ -200,6 +200,9 @@ extern void generic_secondary_thread_init(void); > extern unsigned long __secondary_hold_spinloop; > extern unsigned long __secondary_hold_acknowledge; > extern char __secondary_hold; > +#if defined(CONFIG_KEXEC) || defined(CONFIG_CRASH_DUMP) > +extern unsigned long __run_at_kexec; > +#endif > > extern void __early_start(void); > #endif /* __ASSEMBLY__ */ > diff --git a/arch/powerpc/kernel/head_64.S b/arch/powerpc/kernel/head_64.S > index 3e19ba2..ffa4b18 100644 > --- a/arch/powerpc/kernel/head_64.S > +++ b/arch/powerpc/kernel/head_64.S > @@ -89,6 +89,12 @@ __secondary_hold_spinloop: > __secondary_hold_acknowledge: > .llong 0x0 > > +#if defined(CONFIG_KEXEC) || defined(CONFIG_CRASH_DUMP) > + .globl __run_at_kexec > +__run_at_kexec: > + .llong 0x0 /* Flag for the secondary kernel from kexec. */ > +#endif > + > #ifdef CONFIG_RELOCATABLE > /* This flag is set to 1 by a loader if the kernel should run > * at the loaded address instead of the linked address. This > @@ -417,6 +423,12 @@ _STATIC(__after_prom_start) > #if defined(CONFIG_PPC_BOOK3E) > tovirt(r26,r26) /* on booke, we already run at > PAGE_OFFSET */ > #endif > +#if defined(CONFIG_KEXEC) || defined(CONFIG_CRASH_DUMP) > + /* If relocated we need to restore this flag on that relocated address. */ > + ld r7,__run_at_kexec-_stext(r26) > + std r7,__run_at_kexec-_stext(r26) > +#endif > + > lwz r7,__run_at_load-_stext(r26) > #if defined(CONFIG_PPC_BOOK3E) > tophys(r26,r26) /* Restore for the remains. */ > diff --git a/arch/powerpc/kernel/misc_64.S b/arch/powerpc/kernel/misc_64.S > index 20cbb98..c89aead 100644 > --- a/arch/powerpc/kernel/misc_64.S > +++ b/arch/powerpc/kernel/misc_64.S > @@ -619,6 +619,12 @@ _GLOBAL(kexec_sequence) > bl .copy_and_flush /* (dest, src, copy limit, start offset) */ > 1: /* assume normal blr return */ > > + /* notify we're going into kexec kernel for SMP. */ > + LOAD_REG_ADDR(r3,__run_at_kexec) > + li r4,1 > + std r4,0(r3) > + sync > + > /* release other cpus to the new kernel secondary start at 0x60 */ > mflr r5 > li r6,1 > diff --git a/arch/powerpc/platforms/85xx/smp.c > b/arch/powerpc/platforms/85xx/smp.c > index 6a17599..b308373 100644 > --- a/arch/powerpc/platforms/85xx/smp.c > +++ b/arch/powerpc/platforms/85xx/smp.c > @@ -150,6 +150,9 @@ static int __cpuinit smp_85xx_kick_cpu(int nr) > int hw_cpu = get_hard_smp_processor_id(nr); > int ioremappable; > int ret = 0; > +#if defined(CONFIG_KEXEC) || defined(CONFIG_CRASH_DUMP) > + unsigned long *ptr; > +#endif What about if we can remove the ifdef around *ptr ... > > WARN_ON(nr < 0 || nr >= NR_CPUS); > WARN_ON(hw_cpu < 0 || hw_cpu >= NR_CPUS); > @@ -238,11 +241,22 @@ out: > #else > smp_generic_kick_cpu(nr); > > +#if defined(CONFIG_KEXEC) || defined(CONFIG_CRASH_DUMP) > + ptr = (unsigned long *)((unsigned long)&__run_at_kexec); ... #endif here ... > + /* We shouldn't access spin_table from the bootloader to up any > + * secondary cpu for kexec kernel, and kexec kernel already > + * know how to jump to generic_secondary_smp_init. > + */ > + if (!*ptr) { > +#endif ... remove #endif ... > flush_spin_table(spin_table); > out_be32(&spin_table->pir, hw_cpu); > out_be64((u64 *)(&spin_table->addr_h), > __pa((u64)*((unsigned long long *)generic_secondary_smp_init))); > flush_spin_table(spin_table); > +#if defined(CONFIG_KEXEC) || defined(CONFIG_CRASH_DUMP) > + } > +#endif --- remove above 3 lines -Bharat > #endif > > local_irq_restore(flags); > -- > 1.7.9.5 > > _______________________________________________ > Linuxppc-dev mailing list > Linuxppc-dev@lists.ozlabs.org > https://lists.ozlabs.org/listinfo/linuxppc-dev
On 07/02/2013 01:37 PM, Bhushan Bharat-R65777 wrote: > > >> -----Original Message----- >> From: Linuxppc-dev [mailto:linuxppc-dev- >> bounces+bharat.bhushan=freescale.com@lists.ozlabs.org] On Behalf Of Tiejun Chen >> Sent: Thursday, June 20, 2013 1:23 PM >> To: benh@kernel.crashing.org >> Cc: linuxppc-dev@lists.ozlabs.org; linux-kernel@vger.kernel.org >> Subject: [v2][PATCH 4/7] book3e/kexec/kdump: introduce a kexec kernel flag >> >> We need to introduce a flag to indicate we're already running >> a kexec kernel then we can go proper path. For example, We >> shouldn't access spin_table from the bootloader to up any secondary >> cpu for kexec kernel, and kexec kernel already know how to jump to >> generic_secondary_smp_init. >> >> Signed-off-by: Tiejun Chen <tiejun.chen@windriver.com> >> --- [snip] >> +++ b/arch/powerpc/platforms/85xx/smp.c >> @@ -150,6 +150,9 @@ static int __cpuinit smp_85xx_kick_cpu(int nr) >> int hw_cpu = get_hard_smp_processor_id(nr); >> int ioremappable; >> int ret = 0; >> +#if defined(CONFIG_KEXEC) || defined(CONFIG_CRASH_DUMP) >> + unsigned long *ptr; >> +#endif > > What about if we can remove the ifdef around *ptr ... > >> >> WARN_ON(nr < 0 || nr >= NR_CPUS); >> WARN_ON(hw_cpu < 0 || hw_cpu >= NR_CPUS); >> @@ -238,11 +241,22 @@ out: >> #else >> smp_generic_kick_cpu(nr); >> >> +#if defined(CONFIG_KEXEC) || defined(CONFIG_CRASH_DUMP) >> + ptr = (unsigned long *)((unsigned long)&__run_at_kexec); > > ... #endif here ... > >> + /* We shouldn't access spin_table from the bootloader to up any >> + * secondary cpu for kexec kernel, and kexec kernel already >> + * know how to jump to generic_secondary_smp_init. >> + */ >> + if (!*ptr) { >> +#endif > > ... remove #endif ... > >> flush_spin_table(spin_table); >> out_be32(&spin_table->pir, hw_cpu); >> out_be64((u64 *)(&spin_table->addr_h), >> __pa((u64)*((unsigned long long *)generic_secondary_smp_init))); >> flush_spin_table(spin_table); >> +#if defined(CONFIG_KEXEC) || defined(CONFIG_CRASH_DUMP) >> + } >> +#endif > > --- remove above 3 lines I'd like to try to address your comments next version. Thanks Tiejun
diff --git a/arch/powerpc/include/asm/smp.h b/arch/powerpc/include/asm/smp.h index ffbaabe..fbc3d9b 100644 --- a/arch/powerpc/include/asm/smp.h +++ b/arch/powerpc/include/asm/smp.h @@ -200,6 +200,9 @@ extern void generic_secondary_thread_init(void); extern unsigned long __secondary_hold_spinloop; extern unsigned long __secondary_hold_acknowledge; extern char __secondary_hold; +#if defined(CONFIG_KEXEC) || defined(CONFIG_CRASH_DUMP) +extern unsigned long __run_at_kexec; +#endif extern void __early_start(void); #endif /* __ASSEMBLY__ */ diff --git a/arch/powerpc/kernel/head_64.S b/arch/powerpc/kernel/head_64.S index 3e19ba2..ffa4b18 100644 --- a/arch/powerpc/kernel/head_64.S +++ b/arch/powerpc/kernel/head_64.S @@ -89,6 +89,12 @@ __secondary_hold_spinloop: __secondary_hold_acknowledge: .llong 0x0 +#if defined(CONFIG_KEXEC) || defined(CONFIG_CRASH_DUMP) + .globl __run_at_kexec +__run_at_kexec: + .llong 0x0 /* Flag for the secondary kernel from kexec. */ +#endif + #ifdef CONFIG_RELOCATABLE /* This flag is set to 1 by a loader if the kernel should run * at the loaded address instead of the linked address. This @@ -417,6 +423,12 @@ _STATIC(__after_prom_start) #if defined(CONFIG_PPC_BOOK3E) tovirt(r26,r26) /* on booke, we already run at PAGE_OFFSET */ #endif +#if defined(CONFIG_KEXEC) || defined(CONFIG_CRASH_DUMP) + /* If relocated we need to restore this flag on that relocated address. */ + ld r7,__run_at_kexec-_stext(r26) + std r7,__run_at_kexec-_stext(r26) +#endif + lwz r7,__run_at_load-_stext(r26) #if defined(CONFIG_PPC_BOOK3E) tophys(r26,r26) /* Restore for the remains. */ diff --git a/arch/powerpc/kernel/misc_64.S b/arch/powerpc/kernel/misc_64.S index 20cbb98..c89aead 100644 --- a/arch/powerpc/kernel/misc_64.S +++ b/arch/powerpc/kernel/misc_64.S @@ -619,6 +619,12 @@ _GLOBAL(kexec_sequence) bl .copy_and_flush /* (dest, src, copy limit, start offset) */ 1: /* assume normal blr return */ + /* notify we're going into kexec kernel for SMP. */ + LOAD_REG_ADDR(r3,__run_at_kexec) + li r4,1 + std r4,0(r3) + sync + /* release other cpus to the new kernel secondary start at 0x60 */ mflr r5 li r6,1 diff --git a/arch/powerpc/platforms/85xx/smp.c b/arch/powerpc/platforms/85xx/smp.c index 6a17599..b308373 100644 --- a/arch/powerpc/platforms/85xx/smp.c +++ b/arch/powerpc/platforms/85xx/smp.c @@ -150,6 +150,9 @@ static int __cpuinit smp_85xx_kick_cpu(int nr) int hw_cpu = get_hard_smp_processor_id(nr); int ioremappable; int ret = 0; +#if defined(CONFIG_KEXEC) || defined(CONFIG_CRASH_DUMP) + unsigned long *ptr; +#endif WARN_ON(nr < 0 || nr >= NR_CPUS); WARN_ON(hw_cpu < 0 || hw_cpu >= NR_CPUS); @@ -238,11 +241,22 @@ out: #else smp_generic_kick_cpu(nr); +#if defined(CONFIG_KEXEC) || defined(CONFIG_CRASH_DUMP) + ptr = (unsigned long *)((unsigned long)&__run_at_kexec); + /* We shouldn't access spin_table from the bootloader to up any + * secondary cpu for kexec kernel, and kexec kernel already + * know how to jump to generic_secondary_smp_init. + */ + if (!*ptr) { +#endif flush_spin_table(spin_table); out_be32(&spin_table->pir, hw_cpu); out_be64((u64 *)(&spin_table->addr_h), __pa((u64)*((unsigned long long *)generic_secondary_smp_init))); flush_spin_table(spin_table); +#if defined(CONFIG_KEXEC) || defined(CONFIG_CRASH_DUMP) + } +#endif #endif local_irq_restore(flags);
We need to introduce a flag to indicate we're already running a kexec kernel then we can go proper path. For example, We shouldn't access spin_table from the bootloader to up any secondary cpu for kexec kernel, and kexec kernel already know how to jump to generic_secondary_smp_init. Signed-off-by: Tiejun Chen <tiejun.chen@windriver.com> --- arch/powerpc/include/asm/smp.h | 3 +++ arch/powerpc/kernel/head_64.S | 12 ++++++++++++ arch/powerpc/kernel/misc_64.S | 6 ++++++ arch/powerpc/platforms/85xx/smp.c | 14 ++++++++++++++ 4 files changed, 35 insertions(+)