Applied, thanks!
Damien Zammit via Bug reports for the GNU Hurd, le lun. 09 déc. 2024 12:17:53
+0000, a ecrit:
> Since modern x86 cpus only support 4 bits of destination field
> in ICR, we could only address up to 16 processors, assuming
> their physical APIC ID was < 0x10. Some processors eg AMD fam15h
> have physical apic ids starting at 0x10 but only support 4 bits.
> So these lapics are unaddressable using physical destination mode.
>
> Therefore, we switch to using logical destinations for IPIs which
> gives us 8 bits of unique mask for addressing up to 8 groups of processors.
>
> INIT and STARTUP is not changed here.
>
> ---
> i386/i386/apic.c | 11 ++++++++---
> i386/i386/apic.h | 4 ++++
> i386/i386/ast_check.c | 2 +-
> i386/i386/mp_desc.c | 2 +-
> i386/i386/smp.c | 14 +++++++-------
> i386/i386/smp.h | 4 ++--
> 6 files changed, 23 insertions(+), 14 deletions(-)
>
> diff --git a/i386/i386/apic.c b/i386/i386/apic.c
> index 0b5be50f..41b33599 100644
> --- a/i386/i386/apic.c
> +++ b/i386/i386/apic.c
> @@ -328,15 +328,20 @@ lapic_setup(void)
> unsigned long flags;
> int apic_id;
> volatile uint32_t dummy;
> + int cpu = cpu_number_slow();
>
> cpu_intr_save(&flags);
>
> - apic_id = apic_get_current_cpu();
> + apic_id = apic_get_cpu_apic_id(cpu);
>
> + /* Flat model */
> dummy = lapic->dest_format.r;
> - lapic->dest_format.r = 0xffffffff; /* flat model */
> + lapic->dest_format.r = 0xffffffff;
> +
> + /* Every 8th cpu is in the same logical group */
> dummy = lapic->logical_dest.r;
> - lapic->logical_dest.r = lapic->apic_id.r; /* target self */
> + lapic->logical_dest.r = 0x01000000 << (APIC_LOGICAL_ID(cpu));
> +
> dummy = lapic->lvt_lint0.r;
> lapic->lvt_lint0.r = dummy | LAPIC_DISABLE;
> dummy = lapic->lvt_lint1.r;
> diff --git a/i386/i386/apic.h b/i386/i386/apic.h
> index 9eef0d8b..ec910456 100644
> --- a/i386/i386/apic.h
> +++ b/i386/i386/apic.h
> @@ -312,6 +312,10 @@ extern uint32_t *hpet_addr;
> #define APIC_MSR_X2APIC 0x400 /* LAPIC is in x2APIC mode */
> #define APIC_MSR_ENABLE 0x800 /* LAPIC is enabled */
>
> +/* Since Logical Destination Register only has 8 bits of mask,
> + * we can only address 8 unique groups of cpus for IPIs. */
> +#define APIC_LOGICAL_ID(cpu) ((cpu) % 8)
> +
> /* Set or clear a bit in a 255-bit APIC mask register.
> These registers are spread through eight 32-bit registers. */
> #define APIC_SET_MASK_BIT(reg, bit) \
> diff --git a/i386/i386/ast_check.c b/i386/i386/ast_check.c
> index 61cd5e87..8bf69a68 100644
> --- a/i386/i386/ast_check.c
> +++ b/i386/i386/ast_check.c
> @@ -50,7 +50,7 @@ void init_ast_check(const processor_t processor)
> */
> void cause_ast_check(const processor_t processor)
> {
> - smp_remote_ast(apic_get_cpu_apic_id(processor->slot_num));
> + smp_remote_ast(APIC_LOGICAL_ID(processor->slot_num));
> }
>
> #endif /* NCPUS > 1 */
> diff --git a/i386/i386/mp_desc.c b/i386/i386/mp_desc.c
> index 8455f8ef..f13a391a 100644
> --- a/i386/i386/mp_desc.c
> +++ b/i386/i386/mp_desc.c
> @@ -210,7 +210,7 @@ cpu_control(int cpu, const int *info, unsigned int count)
> void
> interrupt_processor(int cpu)
> {
> - smp_pmap_update(apic_get_cpu_apic_id(cpu));
> + smp_pmap_update(APIC_LOGICAL_ID(cpu));
> }
>
> static void
> diff --git a/i386/i386/smp.c b/i386/i386/smp.c
> index 05e9de67..5861796a 100644
> --- a/i386/i386/smp.c
> +++ b/i386/i386/smp.c
> @@ -48,19 +48,19 @@ static void smp_data_init(void)
>
> }
>
> -static void smp_send_ipi(unsigned apic_id, unsigned vector)
> +static void smp_send_ipi(unsigned logical_id, unsigned vector)
> {
> unsigned long flags;
>
> cpu_intr_save(&flags);
>
> - apic_send_ipi(NO_SHORTHAND, FIXED, PHYSICAL, ASSERT, EDGE, vector,
> apic_id);
> + apic_send_ipi(NO_SHORTHAND, FIXED, LOGICAL, ASSERT, EDGE, vector,
> logical_id);
>
> do {
> cpu_pause();
> } while(lapic->icr_low.delivery_status == SEND_PENDING);
>
> - apic_send_ipi(NO_SHORTHAND, FIXED, PHYSICAL, DE_ASSERT, EDGE, vector,
> apic_id);
> + apic_send_ipi(NO_SHORTHAND, FIXED, LOGICAL, DE_ASSERT, EDGE, vector,
> logical_id);
>
> do {
> cpu_pause();
> @@ -69,14 +69,14 @@ static void smp_send_ipi(unsigned apic_id, unsigned
> vector)
> cpu_intr_restore(flags);
> }
>
> -void smp_remote_ast(unsigned apic_id)
> +void smp_remote_ast(unsigned logical_id)
> {
> - smp_send_ipi(apic_id, CALL_AST_CHECK);
> + smp_send_ipi(logical_id, CALL_AST_CHECK);
> }
>
> -void smp_pmap_update(unsigned apic_id)
> +void smp_pmap_update(unsigned logical_id)
> {
> - smp_send_ipi(apic_id, CALL_PMAP_UPDATE);
> + smp_send_ipi(logical_id, CALL_PMAP_UPDATE);
> }
>
> static void
> diff --git a/i386/i386/smp.h b/i386/i386/smp.h
> index 73d273ef..a34f79da 100644
> --- a/i386/i386/smp.h
> +++ b/i386/i386/smp.h
> @@ -24,8 +24,8 @@
> #include <mach/machine/vm_types.h>
>
> int smp_init(void);
> -void smp_remote_ast(unsigned apic_id);
> -void smp_pmap_update(unsigned apic_id);
> +void smp_remote_ast(unsigned logical_id);
> +void smp_pmap_update(unsigned logical_id);
> int smp_startup_cpu(unsigned apic_id, phys_addr_t start_eip);
>
> #define cpu_pause() asm volatile ("pause" : : : "memory")
> --
> 2.45.2
>
>
>
--
Samuel
<s> cool, j'ai un rapport a rendre pour le 31 decembre a minuit...
-+- #ens-mim - bonne année ! -+-
