1 files changed, 24 insertions, 1 deletions

diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
index fc2f55f2dcd6..e53319cf29cb 100644
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h
@@ -441,9 +441,10 @@
         . = __per_cpu_load + SIZEOF(.data.percpu);
 
 /**
- * PERCPU_VADDR - define output section for percpu area
+ * PERCPU_VADDR_PREALLOC - define output section for percpu area with prealloc
  * @vaddr: explicit base address (optional)
  * @phdr: destination PHDR (optional)
+ * @prealloc: the size of prealloc area
  *
  * Macro which expands to output section for percpu area.  If @vaddr
  * is not blank, it specifies explicit base address and all percpu
@@ -455,11 +456,33 @@
  * section in the linker script will go there too.  @phdr should have
  * a leading colon.
  *
+ * If @prealloc is non-zero, the specified number of bytes will be
+ * reserved at the start of percpu area.  As the prealloc area is
+ * likely to break alignment, this macro puts areas in increasing
+ * alignment order.
+ *
  * This macro defines three symbols, __per_cpu_load, __per_cpu_start
  * and __per_cpu_end.  The first one is the vaddr of loaded percpu
  * init data.  __per_cpu_start equals @vaddr and __per_cpu_end is the
  * end offset.
  */
+#define PERCPU_VADDR_PREALLOC(vaddr, segment, prealloc)                 \
+        PERCPU_PROLOG(vaddr)                                            \
+                . += prealloc;                                          \
+                *(.data.percpu)                                         \
+                *(.data.percpu.shared_aligned)                          \
+                *(.data.percpu.page_aligned)                            \
+        PERCPU_EPILOG(segment)
+
+/**
+ * PERCPU_VADDR - define output section for percpu area
+ * @vaddr: explicit base address (optional)
+ * @phdr: destination PHDR (optional)
+ *
+ * Macro which expands to output section for percpu area.  Mostly
+ * identical to PERCPU_VADDR_PREALLOC(@vaddr, @phdr, 0) other than
+ * using slighly different layout.
+ */
 #define PERCPU_VADDR(vaddr, phdr)                                       \
         PERCPU_PROLOG(vaddr)                                            \
                 *(.data.percpu.page_aligned)                            \