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, 1 insertions, 0 deletions

diff --git a/sys/sys/linker.h b/sys/sys/linker.h
index 4ba7a40..aa705fd 100644
--- a/sys/sys/linker.h
+++ b/sys/sys/linker.h
@@ -264,6 +264,7 @@ typedef Elf_Addr elf_lookup_fn(linker_file_t, Elf_Size, int);
 /* Support functions */
 int	elf_reloc(linker_file_t _lf, Elf_Addr base, const void *_rel, int _type, elf_lookup_fn _lu);
 int	elf_reloc_local(linker_file_t _lf, Elf_Addr base, const void *_rel, int _type, elf_lookup_fn _lu);
+Elf_Addr elf_relocaddr(linker_file_t _lf, Elf_Addr addr);
 const Elf_Sym *elf_get_sym(linker_file_t _lf, Elf_Size _symidx);
 const char *elf_get_symname(linker_file_t _lf, Elf_Size _symidx);