Implement a facility for dynamic per-cpu variables.

 - Modules and kernel code alike may use DPCPU_DEFINE(),
   DPCPU_GET(), DPCPU_SET(), etc. akin to the statically defined
   PCPU_*.  Requires only one extra instruction more than PCPU_* and is
   virtually the same as __thread for builtin and much faster for shared
   objects.  DPCPU variables can be initialized when defined.
 - Modules are supported by relocating the module's per-cpu linker set
   over space reserved in the kernel.  Modules may fail to load if there
   is insufficient space available.
 - Track space available for modules with a one-off extent allocator.
   Free may block for memory to allocate space for an extent.

Reviewed by:    jhb, rwatson, kan, sam, grehan, marius, marcel, stas

1 files changed, 6 insertions, 0 deletions

diff --git a/sys/pc98/pc98/machdep.c b/sys/pc98/pc98/machdep.c
index 0025a8a..f052cee 100644
--- a/sys/pc98/pc98/machdep.c
+++ b/sys/pc98/pc98/machdep.c
@@ -1954,6 +1954,7 @@ init386(first)
 	struct gate_descriptor *gdp;
 	int gsel_tss, metadata_missing, x;
 	struct pcpu *pc;
+	int pa;
 
 	thread0.td_kstack = proc0kstack;
 	thread0.td_pcb = (struct pcb *)
@@ -2010,6 +2011,11 @@ init386(first)
 	lgdt(&r_gdt);
 
 	pcpu_init(pc, 0, sizeof(struct pcpu));
+	for (pa = first; pa < first + DPCPU_SIZE; pa += PAGE_SIZE)
+		pmap_kenter(pa + KERNBASE, pa);
+	dpcpu_init((void *)(first + KERNBASE), 0);
+	first += DPCPU_SIZE;
+
 	PCPU_SET(prvspace, pc);
 	PCPU_SET(curthread, &thread0);
 	PCPU_SET(curpcb, thread0.td_pcb);