Hello,
Damien Zammit, le mar. 25 oct. 2022 10:56:13 +0000, a ecrit:
> diff --git a/i386/i386/gdt.c b/i386/i386/gdt.c
> index fb18360e..44bcd29c 100644
> --- a/i386/i386/gdt.c
> +++ b/i386/i386/gdt.c
> @@ -128,3 +135,39 @@ gdt_init(void)
> #endif /* MACH_PV_PAGETABLES */
> }
>
> +#if NCPUS > 1
> +void
> +ap_gdt_init(int cpu)
> +{
> + gdt_fill(mp_gdt[cpu]);
> +
> +#ifndef MACH_PV_DESCRIPTORS
> + /* Load the new GDT. */
> + {
> + struct pseudo_descriptor pdesc;
> +
> + pdesc.limit = sizeof(gdt)-1;
> + pdesc.linear_base = kvtolin(mp_gdt[cpu]);
> + lgdt(&pdesc);
> + }
> +#endif /* MACH_PV_DESCRIPTORS */
> +
> + /* Reload all the segment registers from the new GDT.
> + We must load ds and es with 0 before loading them with KERNEL_DS
> + because some processors will "optimize out" the loads
> + if the previous selector values happen to be the same. */
> +#ifndef __x86_64__
> + asm volatile("ljmp %0,$1f\n"
> + "1:\n"
> + "movw %w2,%%ds\n"
> + "movw %w2,%%es\n"
> + "movw %w2,%%fs\n"
> + "movw %w2,%%gs\n"
> +
> + "movw %w1,%%ds\n"
> + "movw %w1,%%es\n"
> + "movw %w1,%%ss\n"
> + : : "i" (KERNEL_CS), "r" (KERNEL_DS), "r" (0));
> +#endif
Please factorize this part, it's exactly the same, except gdt vs
mp_gdt[cpu]. Otherwise people will wonder whether there is to be a
difference There is just one trick: sizeof(*(mp_gdt[cpu])) won't
work, but since sizeof(gdt) would assume that ap gdt has the same
size as bsp gdt, better make the size explicit by using sizeof(struct
real_descriptor) * GDTSZ.
> diff --git a/i386/i386/idt-gen.h b/i386/i386/idt-gen.h
> index f86afb41..a94b39c0 100644
> --- a/i386/i386/idt-gen.h
> +++ b/i386/i386/idt-gen.h
> @@ -44,4 +44,8 @@ extern struct real_gate idt[IDTSZ];
> #define fill_idt_gate(int_num, entry, selector, access, dword_count) \
> fill_gate(&idt[int_num], entry, selector, access, dword_count)
>
> +/* Fill a gate in a custom IDT. */
> +#define _fill_idt_gate(_idt, int_num, entry, selector, access, dword_count) \
> + fill_gate(&_idt[int_num], entry, selector, access, dword_count)
> +
> #endif /* _I386_IDT_ */
Rather make fill_idt_gate explicitly take the idt.
> diff --git a/i386/i386/idt.c b/i386/i386/idt.c
> index c6a778f1..8513e158 100644
> --- a/i386/i386/idt.c
> +++ b/i386/i386/idt.c
> @@ -36,7 +37,7 @@ struct idt_init_entry
> };
> extern struct idt_init_entry idt_inittab[];
>
> -void idt_init(void)
> +static void idt_fill(void)
I don't see idt_fill used separately from idt_init?
That said, here again idt_init and ap_idt_init are almost exactly the
same except idt vs mp_desc_table[cpu]->idt, so please factorize (which
will be trivial with fill_idt_gate taking the idt).
> diff --git a/i386/i386/ktss.c b/i386/i386/ktss.c
> index 0d21d3eb..33b084b7 100644
> --- a/i386/i386/ktss.c
> +++ b/i386/i386/ktss.c
> @@ -35,6 +35,7 @@
> #include "seg.h"
> #include "gdt.h"
> #include "ktss.h"
> +#include "mp_desc.h"
>
> /* A kernel TSS with a complete I/O bitmap. */
> struct task_tss ktss;
> @@ -73,3 +74,38 @@ ktss_init(void)
> #endif /* MACH_RING1 */
> }
>
> +#if NCPUS > 1
> +void
> +ap_ktss_init(int cpu)
Again, it's basically exactly the same except gdt vs mp_gdt[cpu] and
&ktss vs &mp_desc_table[cpu]->ktss, please factorize.
> diff --git a/i386/i386/ldt.h b/i386/i386/ldt.h
> index 1f0d7014..55edc396 100644
> --- a/i386/i386/ldt.h
> +++ b/i386/i386/ldt.h
> @@ -64,7 +64,16 @@ extern struct real_descriptor ldt[LDTSZ];
> fill_gate((struct real_gate*)&ldt[sel_idx(selector)], \
> offset, dest_selector, access, word_count)
>
> +/* Fill a 32bit segment descriptor in a custom LDT. */
> +#define _fill_ldt_descriptor(_ldt, selector, base, limit, access, sizebits) \
> + fill_descriptor(&_ldt[sel_idx(selector)], base, limit, access, sizebits)
> +
> +#define _fill_ldt_gate(_ldt, selector, offset, dest_selector, access,
> word_count) \
> + fill_gate((struct real_gate*)&_ldt[sel_idx(selector)], \
> + offset, dest_selector, access, word_count)
Also here, just change fill_ldt_descriptor and fill_ldt_gate to take the
ldt:
> diff --git a/i386/i386/ldt.c b/i386/i386/ldt.c
> index 261df93a..4bbc8e80 100644
> --- a/i386/i386/ldt.c
> +++ b/i386/i386/ldt.c
> @@ -37,6 +37,7 @@
> #include "gdt.h"
> #include "ldt.h"
> #include "locore.h"
> +#include "mp_desc.h"
>
> #ifdef MACH_PV_DESCRIPTORS
> /* It is actually defined in xen_boothdr.S */
> @@ -79,3 +80,41 @@ ldt_init(void)
> lldt(KERNEL_LDT);
> #endif /* MACH_PV_DESCRIPTORS */
> }
> +
> +#if NCPUS > 1
> +void
> +ap_ldt_init(int cpu)
Again :)
> diff --git a/i386/i386/locore.S b/i386/i386/locore.S
> index 162bb13a..8c2f57ea 100644
> --- a/i386/i386/locore.S
> +++ b/i386/i386/locore.S
> @@ -649,6 +649,10 @@ INTERRUPT(20)
> INTERRUPT(21)
> INTERRUPT(22)
> INTERRUPT(23)
> +#endif
> +/* Invalidate TLB IPI to call pmap_update_interrupt() on a specific cpu */
> +INTERRUPT(251)
Better make it use the CALL_SINGLE_FUNCTION_BASE macro. You can use
i386/i386/i386asm.sym to get it.
> diff --git a/i386/i386at/int_init.c b/i386/i386at/int_init.c
> index 6da627dd..6c242557 100644
> --- a/i386/i386at/int_init.c
> +++ b/i386/i386at/int_init.c
> @@ -23,6 +23,7 @@
>
> #include <i386at/idt.h>
> #include <i386/gdt.h>
> +#include <i386/mp_desc.h>
>
> /* defined in locore.S */
> extern vm_offset_t int_entry_table[];
> @@ -36,15 +37,38 @@ void int_init(void)
> int_entry_table[i], KERNEL_CS,
> ACC_PL_K|ACC_INTR_GATE, 0);
> }
> + fill_idt_gate(CALL_SINGLE_FUNCTION_BASE,
> + int_entry_table[16], KERNEL_CS,
> + ACC_PL_K|ACC_INTR_GATE, 0);
> #else
> for (i = 0; i < 24; i++) {
> fill_idt_gate(IOAPIC_INT_BASE + i,
> int_entry_table[i], KERNEL_CS,
> ACC_PL_K|ACC_INTR_GATE, 0);
> }
> - fill_idt_gate(IOAPIC_SPURIOUS_BASE,
> + fill_idt_gate(CALL_SINGLE_FUNCTION_BASE,
> int_entry_table[24], KERNEL_CS,
> ACC_PL_K|ACC_INTR_GATE, 0);
> + fill_idt_gate(IOAPIC_SPURIOUS_BASE,
> + int_entry_table[25], KERNEL_CS,
> + ACC_PL_K|ACC_INTR_GATE, 0);
> #endif
I'd rather see it factorized, with
#ifndef APIC
int cur = PIC_INT_BASE;
int nirq = 16;
#else
int cur = IOAPIC_INT_BASE;
int nirq = 24;
#endif
and then use cur and cur++ in the loop, and simply put the
IOAPIC_SPURIOUS_BASE addition in #ifdef APIC.
> }
>
> +#if NCPUS > 1
> +void ap_int_init(int cpu)
> +{
Why not setting gates for the hardware IRQs? At some point we'll
probably want to distribute IRQs over cpus. And then we can again just
factorize both functions.
> +#ifndef APIC
> + _fill_idt_gate(mp_desc_table[cpu]->idt, CALL_SINGLE_FUNCTION_BASE,
> + int_entry_table[16], KERNEL_CS,
> + ACC_PL_K|ACC_INTR_GATE, 0);
> +#else
> + _fill_idt_gate(mp_desc_table[cpu]->idt, CALL_SINGLE_FUNCTION_BASE,
> + int_entry_table[24], KERNEL_CS,
> + ACC_PL_K|ACC_INTR_GATE, 0);
> + _fill_idt_gate(mp_desc_table[cpu]->idt, IOAPIC_SPURIOUS_BASE,
> + int_entry_table[25], KERNEL_CS,
> + ACC_PL_K|ACC_INTR_GATE, 0);
> +#endif
> +}
> +#endif
> diff --git a/i386/i386at/interrupt.S b/i386/i386at/interrupt.S
> index 8fd18392..a5aac966 100644
> --- a/i386/i386at/interrupt.S
> +++ b/i386/i386at/interrupt.S
> @@ -41,6 +41,9 @@ ENTRY(interrupt)
> cmpl $255,%eax /* was this a spurious intr? */
> je _no_eoi /* if so, just return */
> #endif
> + cmpl $251,%eax /* was this a SMP call single function
> request? */
> + je _call_single
> +
> subl $28,%esp /* Two local variables + 5 parameters */
> movl %eax,S_IRQ /* save irq number */
> call spl7 /* set ipl */
> @@ -118,4 +121,7 @@ _isa_eoi:
> addl $28,%esp /* pop local variables */
> _no_eoi:
> ret
> +_call_single:
> + call EXT(pmap_update_interrupt) /* TODO: Allow other functions */
I believe you still want to call pmap_update_interrupt under spl7, so
add calling spl7 and splx_cli. Do we not need an eoi notification?
> + ret
> END(interrupt)
> --
> 2.34.1
