From 28fc7afa4d5578c672cd11ad65f8eea80c26873c Mon Sep 17 00:00:00 2001
From: Tejun Heo <tj@kernel.org>
Date: Thu, 24 Sep 2009 18:18:55 +0900
Subject: [PATCH] --- yaml --- r: 166512 b: refs/heads/master c:
 a70c691376c7c7f94af41395848066f59501fffd h: refs/heads/master v: v3

---
 [refs]                           |  2 +-
 trunk/arch/sparc/Kconfig         |  3 ++
 trunk/arch/sparc/kernel/smp_64.c | 53 ++++++++++++++++++++++++++------
 3 files changed, 48 insertions(+), 10 deletions(-)

diff --git a/[refs] b/[refs]
index 28b32bdb8402..d61750f3c3eb 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: fb59e72e7e10fd9d31f4e522f1b28254c2cc8a6c
+refs/heads/master: a70c691376c7c7f94af41395848066f59501fffd
diff --git a/trunk/arch/sparc/Kconfig b/trunk/arch/sparc/Kconfig
index 97fca4695e0b..ac45aab741a5 100644
--- a/trunk/arch/sparc/Kconfig
+++ b/trunk/arch/sparc/Kconfig
@@ -102,6 +102,9 @@ config HAVE_SETUP_PER_CPU_AREA
 config NEED_PER_CPU_EMBED_FIRST_CHUNK
 	def_bool y if SPARC64
 
+config NEED_PER_CPU_PAGE_FIRST_CHUNK
+	def_bool y if SPARC64
+
 config GENERIC_HARDIRQS_NO__DO_IRQ
 	bool
 	def_bool y if SPARC64
diff --git a/trunk/arch/sparc/kernel/smp_64.c b/trunk/arch/sparc/kernel/smp_64.c
index ff68373ce6d6..aa36223497b9 100644
--- a/trunk/arch/sparc/kernel/smp_64.c
+++ b/trunk/arch/sparc/kernel/smp_64.c
@@ -1420,7 +1420,7 @@ static void __init pcpu_free_bootmem(void *ptr, size_t size)
 	free_bootmem(__pa(ptr), size);
 }
 
-static int pcpu_cpu_distance(unsigned int from, unsigned int to)
+static int __init pcpu_cpu_distance(unsigned int from, unsigned int to)
 {
 	if (cpu_to_node(from) == cpu_to_node(to))
 		return LOCAL_DISTANCE;
@@ -1428,18 +1428,53 @@ static int pcpu_cpu_distance(unsigned int from, unsigned int to)
 		return REMOTE_DISTANCE;
 }
 
+static void __init pcpu_populate_pte(unsigned long addr)
+{
+	pgd_t *pgd = pgd_offset_k(addr);
+	pud_t *pud;
+	pmd_t *pmd;
+
+	pud = pud_offset(pgd, addr);
+	if (pud_none(*pud)) {
+		pmd_t *new;
+
+		new = __alloc_bootmem(PAGE_SIZE, PAGE_SIZE, PAGE_SIZE);
+		pud_populate(&init_mm, pud, new);
+	}
+
+	pmd = pmd_offset(pud, addr);
+	if (!pmd_present(*pmd)) {
+		pte_t *new;
+
+		new = __alloc_bootmem(PAGE_SIZE, PAGE_SIZE, PAGE_SIZE);
+		pmd_populate_kernel(&init_mm, pmd, new);
+	}
+}
+
 void __init setup_per_cpu_areas(void)
 {
 	unsigned long delta;
 	unsigned int cpu;
-	int rc;
-
-	rc = pcpu_embed_first_chunk(PERCPU_MODULE_RESERVE,
-				    PERCPU_DYNAMIC_RESERVE, 4 << 20,
-				    pcpu_cpu_distance, pcpu_alloc_bootmem,
-				    pcpu_free_bootmem);
-	if (rc)
-		panic("failed to initialize first chunk (%d)", rc);
+	int rc = -EINVAL;
+
+	if (pcpu_chosen_fc != PCPU_FC_PAGE) {
+		rc = pcpu_embed_first_chunk(PERCPU_MODULE_RESERVE,
+					    PERCPU_DYNAMIC_RESERVE, 4 << 20,
+					    pcpu_cpu_distance,
+					    pcpu_alloc_bootmem,
+					    pcpu_free_bootmem);
+		if (rc)
+			pr_warning("PERCPU: %s allocator failed (%d), "
+				   "falling back to page size\n",
+				   pcpu_fc_names[pcpu_chosen_fc], rc);
+	}
+	if (rc < 0)
+		rc = pcpu_page_first_chunk(PERCPU_MODULE_RESERVE,
+					   pcpu_alloc_bootmem,
+					   pcpu_free_bootmem,
+					   pcpu_populate_pte);
+	if (rc < 0)
+		panic("cannot initialize percpu area (err=%d)", rc);
 
 	delta = (unsigned long)pcpu_base_addr - (unsigned long)__per_cpu_start;
 	for_each_possible_cpu(cpu)