[PATCH 5/5 gnumach] smp: Parallel SMP init

[Damien Zammit]

Now that things are in place, we switch to parallel init.
The key to this change is that the INIT/STARTUP sequence
is done in one step, and all cpus wake up at the same time.
Synchronisation is done to complete each cpu setup individually.
---
 i386/i386/mp_desc.c | 51 +++++++++++++++------------------------------
 i386/i386/mp_desc.h |  2 --
 i386/i386/smp.c     | 20 +++++++++---------
 i386/i386/smp.h     |  2 +-
 kern/processor.c    |  4 ----
 5 files changed, 28 insertions(+), 51 deletions(-)

diff --git a/i386/i386/mp_desc.c b/i386/i386/mp_desc.c
index 295fccc7..12583c9e 100644
--- a/i386/i386/mp_desc.c
+++ b/i386/i386/mp_desc.c
@@ -233,9 +233,8 @@ paging_enable(void)
 void
 cpu_setup(int cpu)
 {
-    pmap_make_temporary_mapping();
     pmap_set_page_dir();
-    printf("AP=(%u) tempmap done\n", cpu);
+    printf("AP=(%u) pagedir done\n", cpu);
 
     paging_enable();
     flush_instr_queue();
@@ -259,13 +258,6 @@ cpu_setup(int cpu)
     ap_ktss_init(cpu);
     printf("AP=(%u) ktss done\n", cpu);
 
-    pmap_remove_temporary_mapping();
-    printf("AP=(%u) remove tempmap done\n", cpu);
-
-    pmap_set_page_dir();
-    flush_tlb();
-    printf("AP=(%u) reset page dir done\n", cpu);
-
     /* Initialize machine_slot fields with the cpu data */
     machine_slot[cpu].cpu_subtype = CPU_SUBTYPE_AT386;
     machine_slot[cpu].cpu_type = machine_slot[0].cpu_type;
@@ -286,34 +278,13 @@ cpu_ap_main(void)
 
     do {
        cpu_pause();
-    } while (bspdone != cpu);
+    } while (bspdone < cpu);
 
     __sync_synchronize();
 
     cpu_setup(cpu);
 }
 
-kern_return_t
-cpu_start(int cpu)
-{
-    int err;
-
-    assert(machine_slot[cpu].running != TRUE);
-
-    uint16_t apic_id = apic_get_cpu_apic_id(cpu);
-
-    printf("Trying to enable: %d at 0x%lx\n", apic_id, apboot_addr);
-
-    err = smp_startup_cpu(apic_id, apboot_addr);
-
-    if (!err) {
-        printf("Started cpu %d (lapic id %04x)\n", cpu, apic_id);
-        return KERN_SUCCESS;
-    }
-    printf("FATAL: Cannot init AP %d\n", cpu);
-    for (;;);
-}
-
 void
 start_other_cpus(void)
 {
@@ -341,12 +312,16 @@ start_other_cpus(void)
        lapic_disable();
 
        bspdone = 0;
+
+       /* This is set once for all APs to use */
+       pmap_make_temporary_mapping();
+
+       smp_startup_cpus(apic_get_cpu_apic_id(0), apboot_addr);
+
        for (cpu = 1; cpu < ncpus; cpu++) {
                machine_slot[cpu].running = FALSE;
 
-               //Start cpu
-               printf("Starting AP %d\n", cpu);
-               cpu_start(cpu);
+               printf("Waiting for AP %d\n", cpu);
 
                bspdone++;
                do {
@@ -357,6 +332,14 @@ start_other_cpus(void)
        }
        printf("BSP: Completed SMP init\n");
 
+       pmap_remove_temporary_mapping();
+
+       /* Flush TLB on all cpu groups */
+       ncpus = (ncpus < 8) ? ncpus : 8;
+       for (cpu = 1; cpu < ncpus; cpu++) {
+               interrupt_processor(cpu);
+       }
+
        /* Re-enable IOAPIC interrupts as per setup */
        lapic_enable();
        spl_init = 1;
diff --git a/i386/i386/mp_desc.h b/i386/i386/mp_desc.h
index dc3a7dc8..6af311b7 100644
--- a/i386/i386/mp_desc.h
+++ b/i386/i386/mp_desc.h
@@ -89,8 +89,6 @@ extern void interrupt_processor(int cpu);
 
 extern void start_other_cpus(void);
 
-extern kern_return_t cpu_start(int cpu);
-
 extern kern_return_t cpu_control(int cpu, const int *info, unsigned int count);
 
 extern void interrupt_stack_alloc(void);
diff --git a/i386/i386/smp.c b/i386/i386/smp.c
index 5861796a..befa0510 100644
--- a/i386/i386/smp.c
+++ b/i386/i386/smp.c
@@ -90,7 +90,7 @@ wait_for_ipi(void)
 }
 
 static int
-smp_send_ipi_init(int apic_id)
+smp_send_ipi_init(int bsp_apic_id)
 {
     int err;
 
@@ -100,7 +100,7 @@ smp_send_ipi_init(int apic_id)
      *
      * This is EDGE triggered to match the deassert
      */
-    apic_send_ipi(NO_SHORTHAND, INIT, PHYSICAL, ASSERT, EDGE, 0, apic_id);
+    apic_send_ipi(ALL_EXCLUDING_SELF, INIT, PHYSICAL, ASSERT, EDGE, 0, 
bsp_apic_id);
 
     /* Wait for delivery */
     wait_for_ipi();
@@ -113,7 +113,7 @@ smp_send_ipi_init(int apic_id)
      * that does not support STARTUP IPIs at all, and instead jump
      * via a warm reset vector.
      */
-    apic_send_ipi(NO_SHORTHAND, INIT, PHYSICAL, DE_ASSERT, EDGE, 0, apic_id);
+    apic_send_ipi(ALL_EXCLUDING_SELF, INIT, PHYSICAL, DE_ASSERT, EDGE, 0, 
bsp_apic_id);
 
     /* Wait for delivery */
     wait_for_ipi();
@@ -126,7 +126,7 @@ smp_send_ipi_init(int apic_id)
 }
 
 static int
-smp_send_ipi_startup(int apic_id, int vector)
+smp_send_ipi_startup(int bsp_apic_id, int vector)
 {
     int err;
 
@@ -137,7 +137,7 @@ smp_send_ipi_startup(int apic_id, int vector)
      * Have not seen any documentation for trigger mode for this IPI
      * but it seems to work with EDGE.  (AMD BKDG FAM16h document specifies 
dont care)
      */
-    apic_send_ipi(NO_SHORTHAND, STARTUP, PHYSICAL, ASSERT, EDGE, vector, 
apic_id);
+    apic_send_ipi(ALL_EXCLUDING_SELF, STARTUP, PHYSICAL, ASSERT, EDGE, vector, 
bsp_apic_id);
 
     /* Wait for delivery */
     wait_for_ipi();
@@ -150,7 +150,7 @@ smp_send_ipi_startup(int apic_id, int vector)
 }
 
 /* See Intel IA32/64 Software Developer's Manual 3A Section 8.4.4.1 */
-int smp_startup_cpu(unsigned apic_id, phys_addr_t start_eip)
+int smp_startup_cpus(unsigned bsp_apic_id, phys_addr_t start_eip)
 {
 #if 0
     /* This block goes with a legacy method of INIT that only works with
@@ -174,13 +174,13 @@ int smp_startup_cpu(unsigned apic_id, phys_addr_t 
start_eip)
     /* Local cache flush */
     asm("wbinvd":::"memory");
 
-    printf("Sending IPIs to APIC ID %u...\n", apic_id);
+    printf("Sending IPIs from BSP APIC ID %u...\n", bsp_apic_id);
 
-    smp_send_ipi_init(apic_id);
+    smp_send_ipi_init(bsp_apic_id);
     hpet_mdelay(10);
-    smp_send_ipi_startup(apic_id, start_eip >> STARTUP_VECTOR_SHIFT);
+    smp_send_ipi_startup(bsp_apic_id, start_eip >> STARTUP_VECTOR_SHIFT);
     hpet_udelay(200);
-    smp_send_ipi_startup(apic_id, start_eip >> STARTUP_VECTOR_SHIFT);
+    smp_send_ipi_startup(bsp_apic_id, start_eip >> STARTUP_VECTOR_SHIFT);
     hpet_udelay(200);
 
     printf("done\n");
diff --git a/i386/i386/smp.h b/i386/i386/smp.h
index a34f79da..13b01787 100644
--- a/i386/i386/smp.h
+++ b/i386/i386/smp.h
@@ -26,7 +26,7 @@
 int smp_init(void);
 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);
+int smp_startup_cpus(unsigned bsp_apic_id, phys_addr_t start_eip);
 
 #define cpu_pause() asm volatile ("pause" : : : "memory")
 #define STARTUP_VECTOR_SHIFT   (20 - 8)
diff --git a/kern/processor.c b/kern/processor.c
index 0e42fa37..ba82ca2a 100644
--- a/kern/processor.c
+++ b/kern/processor.c
@@ -452,11 +452,7 @@ kern_return_t processor_start(
 {
        if (processor == PROCESSOR_NULL)
                return KERN_INVALID_ARGUMENT;
-#if    NCPUS > 1
-       return cpu_start(processor->slot_num);
-#else  /* NCPUS > 1 */
        return KERN_FAILURE;
-#endif /* NCPUS > 1 */
 }
 
 kern_return_t processor_exit(
-- 
2.45.2