- Update to 3.4-rc7.
[linux-flexiantxendom0-3.2.10.git] / arch / x86 / kernel / setup_percpu.c
index d748199..2e440b9 100644 (file)
@@ -185,10 +185,22 @@ void __init setup_per_cpu_areas(void)
 #endif
        rc = -EINVAL;
        if (pcpu_chosen_fc != PCPU_FC_PAGE) {
-               const size_t atom_size = cpu_has_pse ? PMD_SIZE : PAGE_SIZE;
                const size_t dyn_size = PERCPU_MODULE_RESERVE +
                        PERCPU_DYNAMIC_RESERVE - PERCPU_FIRST_CHUNK_RESERVE;
+               size_t atom_size;
 
+               /*
+                * On 64bit, use PMD_SIZE for atom_size so that embedded
+                * percpu areas are aligned to PMD.  This, in the future,
+                * can also allow using PMD mappings in vmalloc area.  Use
+                * PAGE_SIZE on 32bit as vmalloc space is highly contended
+                * and large vmalloc area allocs can easily fail.
+                */
+#ifdef CONFIG_X86_64
+               atom_size = PMD_SIZE;
+#else
+               atom_size = PAGE_SIZE;
+#endif
                rc = pcpu_embed_first_chunk(PERCPU_FIRST_CHUNK_RESERVE,
                                            dyn_size, atom_size,
                                            pcpu_cpu_distance,