From: Pavel Tatashin <pasha.tatashin@oracle.com>
Date: Wed, 31 May 2017 15:25:23 +0000 (-0400)
Subject: sparc64: add per-cpu mm of secondary contexts
X-Git-Tag: v4.1.12-105.0.20170705_2000~27
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=d729a8efa2659259eeffb542250c468edf343eae;p=users%2Fjedix%2Flinux-maple.git

sparc64: add per-cpu mm of secondary contexts

The new wrap is going to use information from this array to figure out
mm's that currently have valid secondary contexts setup.

Orabug: 25999953

Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Reviewed-by: Bob Picco <bob.picco@oracle.com>
Reviewed-by: Steven Sistare <steven.sistare@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

(cherry picked from commit 7a5b4bbf49fe86ce77488a70c5dccfe2d50d7a2d)
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Reviewed-by: Steven Sistare <steven.sistare@oracle.com>
Signed-off-by: Allen Pais <allen.pais@oracle.com>
---

diff --git a/arch/sparc/include/asm/mmu_context_64.h b/arch/sparc/include/asm/mmu_context_64.h
index 715784fd23f35..0fec7ffc1ea9d 100644
--- a/arch/sparc/include/asm/mmu_context_64.h
+++ b/arch/sparc/include/asm/mmu_context_64.h
@@ -19,6 +19,7 @@ extern unsigned long tlb_context_cache;
 extern unsigned long ctx_nr_bits;
 extern unsigned long mmu_context_bmap[];
 
+DECLARE_PER_CPU(struct mm_struct *, per_cpu_secondary_mm);
 void get_new_mmu_context(struct mm_struct *mm);
 #ifdef CONFIG_SMP
 void smp_new_mmu_context_version(void);
@@ -76,8 +77,9 @@ void __flush_tlb_mm(unsigned long, unsigned long);
 static inline void switch_mm(struct mm_struct *old_mm, struct mm_struct *mm, struct task_struct *tsk)
 {
 	unsigned long ctx_valid, flags;
-	int cpu;
+	int cpu = smp_processor_id();
 
+	per_cpu(per_cpu_secondary_mm, cpu) = mm;
 	if (unlikely(mm == &init_mm))
 		return;
 
@@ -123,7 +125,6 @@ static inline void switch_mm(struct mm_struct *old_mm, struct mm_struct *mm, str
 	 * for the first time, we must flush that context out of the
 	 * local TLB.
 	 */
-	cpu = smp_processor_id();
 	if (!ctx_valid || !cpumask_test_cpu(cpu, mm_cpumask(mm))) {
 		cpumask_set_cpu(cpu, mm_cpumask(mm));
 		__flush_tlb_mm(CTX_HWBITS(mm->context),
diff --git a/arch/sparc/mm/init_64.c b/arch/sparc/mm/init_64.c
index 3c6bb9fb31fa5..17facc588b72e 100644
--- a/arch/sparc/mm/init_64.c
+++ b/arch/sparc/mm/init_64.c
@@ -855,6 +855,7 @@ DEFINE_SPINLOCK(ctx_alloc_lock);
 unsigned long tlb_context_cache = CTX_FIRST_VERSION;
 #define CTX_BMAP_SLOTS	BITS_TO_LONGS(MAX_CTX_NR)
 DECLARE_BITMAP(mmu_context_bmap, MAX_CTX_NR);
+DEFINE_PER_CPU(struct mm_struct *, per_cpu_secondary_mm) = {0};
 
 /* Caller does TLB context flushing on local CPU if necessary.
  * The caller also ensures that CTX_VALID(mm->context) is false.