| Message ID | 20170519092837.30991-1-yousaf.kaukab@suse.com (mailing list archive) |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
On 19/05/17 10:28, Mian Yousaf Kaukab wrote: > Low Power Idle(LPI) support added acpi_processor_ffh_lpi_probe() and > acpi_processor_ffh_lpi_enter() as __weak functions and arch code is > supposed to provide the actual callbacks. This breaks if > ACPI_PROCESSOR is configured as a module. > > Add CONFIG_ARCH_HAS_ACPI_LPI configuration option to fix this. > Rafael didn't like the extra Kconfig option when I first posted LPI patches. > Signed-off-by: Mian Yousaf Kaukab <yousaf.kaukab@suse.com> > --- > arch/arm64/Kconfig | 1 + > arch/arm64/kernel/cpuidle.c | 2 ++ > drivers/acpi/Kconfig | 3 +++ > drivers/acpi/processor_idle.c | 9 +++++++-- > 4 files changed, 13 insertions(+), 2 deletions(-) > > diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig > index 848a34116c67..de2f2779cdf5 100644 > --- a/arch/arm64/Kconfig > +++ b/arch/arm64/Kconfig > @@ -10,6 +10,7 @@ config ARM64 > select ARCH_HAS_DEBUG_VIRTUAL > select ARCH_HAS_DEVMEM_IS_ALLOWED > select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI > + select ARCH_HAS_ACPI_LPI if ACPI > select ARCH_HAS_ELF_RANDOMIZE > select ARCH_HAS_GCOV_PROFILE_ALL > select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA > diff --git a/arch/arm64/kernel/cpuidle.c b/arch/arm64/kernel/cpuidle.c > index fd691087dc9a..002d9cb890bd 100644 > --- a/arch/arm64/kernel/cpuidle.c > +++ b/arch/arm64/kernel/cpuidle.c > @@ -51,9 +51,11 @@ int acpi_processor_ffh_lpi_probe(unsigned int cpu) > { > return arm_cpuidle_init(cpu); > } > +EXPORT_SYMBOL(acpi_processor_ffh_lpi_probe); > > int acpi_processor_ffh_lpi_enter(struct acpi_lpi_state *lpi) > { > return CPU_PM_CPU_IDLE_ENTER(arm_cpuidle_suspend, lpi->index); > } > +EXPORT_SYMBOL(acpi_processor_ffh_lpi_enter); Won't these 2 export suffice ? I am just curious why that won't work. Will weak function definitions be still picked when built as modules ?
On 5/23/17 3:08 PM, Sudeep Holla wrote: > > > On 19/05/17 10:28, Mian Yousaf Kaukab wrote: >> Low Power Idle(LPI) support added acpi_processor_ffh_lpi_probe() and >> acpi_processor_ffh_lpi_enter() as __weak functions and arch code is >> supposed to provide the actual callbacks. This breaks if >> ACPI_PROCESSOR is configured as a module. >> >> Add CONFIG_ARCH_HAS_ACPI_LPI configuration option to fix this. >> > > Rafael didn't like the extra Kconfig option when I first posted > LPI patches. > >> Signed-off-by: Mian Yousaf Kaukab <yousaf.kaukab@suse.com> >> --- >> arch/arm64/Kconfig | 1 + >> arch/arm64/kernel/cpuidle.c | 2 ++ >> drivers/acpi/Kconfig | 3 +++ >> drivers/acpi/processor_idle.c | 9 +++++++-- >> 4 files changed, 13 insertions(+), 2 deletions(-) >> >> diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig >> index 848a34116c67..de2f2779cdf5 100644 >> --- a/arch/arm64/Kconfig >> +++ b/arch/arm64/Kconfig >> @@ -10,6 +10,7 @@ config ARM64 >> select ARCH_HAS_DEBUG_VIRTUAL >> select ARCH_HAS_DEVMEM_IS_ALLOWED >> select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI >> + select ARCH_HAS_ACPI_LPI if ACPI >> select ARCH_HAS_ELF_RANDOMIZE >> select ARCH_HAS_GCOV_PROFILE_ALL >> select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA >> diff --git a/arch/arm64/kernel/cpuidle.c b/arch/arm64/kernel/cpuidle.c >> index fd691087dc9a..002d9cb890bd 100644 >> --- a/arch/arm64/kernel/cpuidle.c >> +++ b/arch/arm64/kernel/cpuidle.c >> @@ -51,9 +51,11 @@ int acpi_processor_ffh_lpi_probe(unsigned int cpu) >> { >> return arm_cpuidle_init(cpu); >> } >> +EXPORT_SYMBOL(acpi_processor_ffh_lpi_probe); >> >> int acpi_processor_ffh_lpi_enter(struct acpi_lpi_state *lpi) >> { >> return CPU_PM_CPU_IDLE_ENTER(arm_cpuidle_suspend, lpi->index); >> } >> +EXPORT_SYMBOL(acpi_processor_ffh_lpi_enter); > > Won't these 2 export suffice ? [...] No, they don't suffice. > [...] I am just curious why that won't work. I am not really sure. System.map shows the exported symbols as following: ffff000008095898 T acpi_processor_ffh_lpi_probe ffff0000080958f8 T acpi_processor_ffh_lpi_enter ffff000008c19160 R __ksymtab_acpi_processor_ffh_lpi_enter ffff000008c19170 R __ksymtab_acpi_processor_ffh_lpi_probe ffff000008c357f0 r __kcrctab_acpi_processor_ffh_lpi_enter ffff000008c357f8 r __kcrctab_acpi_processor_ffh_lpi_probe ffff000008c4361b r __kstrtab_acpi_processor_ffh_lpi_enter ffff000008c43638 r __kstrtab_acpi_processor_ffh_lpi_probe and 'nm processor.ko' shows that they are defined as weak: 0000000000000d68 W acpi_processor_ffh_lpi_enter 0000000000000cc8 W acpi_processor_ffh_lpi_probe But still weak symbols are happily used when the module is inserted. > Will weak function definitions be still picked when built as modules ? Yes. BR, Yousaf
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 848a34116c67..de2f2779cdf5 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -10,6 +10,7 @@ config ARM64 select ARCH_HAS_DEBUG_VIRTUAL select ARCH_HAS_DEVMEM_IS_ALLOWED select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI + select ARCH_HAS_ACPI_LPI if ACPI select ARCH_HAS_ELF_RANDOMIZE select ARCH_HAS_GCOV_PROFILE_ALL select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA diff --git a/arch/arm64/kernel/cpuidle.c b/arch/arm64/kernel/cpuidle.c index fd691087dc9a..002d9cb890bd 100644 --- a/arch/arm64/kernel/cpuidle.c +++ b/arch/arm64/kernel/cpuidle.c @@ -51,9 +51,11 @@ int acpi_processor_ffh_lpi_probe(unsigned int cpu) { return arm_cpuidle_init(cpu); } +EXPORT_SYMBOL(acpi_processor_ffh_lpi_probe); int acpi_processor_ffh_lpi_enter(struct acpi_lpi_state *lpi) { return CPU_PM_CPU_IDLE_ENTER(arm_cpuidle_suspend, lpi->index); } +EXPORT_SYMBOL(acpi_processor_ffh_lpi_enter); #endif diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig index 1ce52f84dc23..7e5a7bce9d72 100644 --- a/drivers/acpi/Kconfig +++ b/drivers/acpi/Kconfig @@ -224,6 +224,9 @@ config ACPI_PROCESSOR_IDLE bool select CPU_IDLE +config ARCH_HAS_ACPI_LPI + def_bool n + config ACPI_MCFG bool diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c index 5c8aa9cf62d7..321fe9acd8e8 100644 --- a/drivers/acpi/processor_idle.c +++ b/drivers/acpi/processor_idle.c @@ -1211,15 +1211,20 @@ static int acpi_processor_get_lpi_info(struct acpi_processor *pr) return 0; } -int __weak acpi_processor_ffh_lpi_probe(unsigned int cpu) +#ifdef CONFIG_ARCH_HAS_ACPI_LPI +int acpi_processor_ffh_lpi_probe(unsigned int cpu); +int acpi_processor_ffh_lpi_enter(struct acpi_lpi_state *lpi); +#else +static int acpi_processor_ffh_lpi_probe(unsigned int cpu) { return -ENODEV; } -int __weak acpi_processor_ffh_lpi_enter(struct acpi_lpi_state *lpi) +static int acpi_processor_ffh_lpi_enter(struct acpi_lpi_state *lpi) { return -ENODEV; } +#endif /* CONFIG_ARCH_HAS_ACPI_LPI */ /** * acpi_idle_lpi_enter - enters an ACPI any LPI state
Low Power Idle(LPI) support added acpi_processor_ffh_lpi_probe() and acpi_processor_ffh_lpi_enter() as __weak functions and arch code is supposed to provide the actual callbacks. This breaks if ACPI_PROCESSOR is configured as a module. Add CONFIG_ARCH_HAS_ACPI_LPI configuration option to fix this. Signed-off-by: Mian Yousaf Kaukab <yousaf.kaukab@suse.com> --- arch/arm64/Kconfig | 1 + arch/arm64/kernel/cpuidle.c | 2 ++ drivers/acpi/Kconfig | 3 +++ drivers/acpi/processor_idle.c | 9 +++++++-- 4 files changed, 13 insertions(+), 2 deletions(-)