Merge branch 'for-3.4-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu

Pull two percpu fixes from Tejun Heo:
 "One adds missing KERN_CONT on split printk()s and the other makes
  the percpu allocator avoid using PMD_SIZE as atom_size on x86_32.

  Using PMD_SIZE led to vmalloc area exhaustion on certain
  configurations (x86_32 android) and the only cost of using PAGE_SIZE
  instead is static percpu area not being aligned to large page
  mapping."

* 'for-3.4-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/percpu:
  percpu, x86: don't use PMD_SIZE as embedded atom_size on 32bit
  percpu: use KERN_CONT in pcpu_dump_alloc_info()

1 files changed, 13 insertions, 1 deletions

diff --git a/arch/x86/kernel/setup_percpu.c b/arch/x86/kernel/setup_percpu.c
index 71f4727da373..5a98aa272184 100644
--- a/arch/x86/kernel/setup_percpu.c
+++ b/arch/x86/kernel/setup_percpu.c
@@ -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,