powerpc: mmu_gather rework
Fix up powerpc to the new mmu_gather stuff.
PPC has an extra batching queue to RCU free the actual pagetable
allocations, use the ARCH extentions for that for now.
For the ppc64_tlb_batch, which tracks the vaddrs to unhash from the
hardware hash-table, keep using per-cpu arrays but flush on context switch
and use a TLF bit to track the lazy_mmu state.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Miller <davem@davemloft.net>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Richard Weinberger <richard@nod.at>
Cc: Tony Luck <tony.luck@intel.com>
Cc: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Mel Gorman <mel@csn.ul.ie>
Cc: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/arch/powerpc/include/asm/pgalloc.h b/arch/powerpc/include/asm/pgalloc.h
index abe8532..df1b4cb 100644
--- a/arch/powerpc/include/asm/pgalloc.h
+++ b/arch/powerpc/include/asm/pgalloc.h
@@ -32,13 +32,13 @@
#ifdef CONFIG_SMP
extern void pgtable_free_tlb(struct mmu_gather *tlb, void *table, unsigned shift);
-extern void pte_free_finish(void);
+extern void pte_free_finish(struct mmu_gather *tlb);
#else /* CONFIG_SMP */
static inline void pgtable_free_tlb(struct mmu_gather *tlb, void *table, unsigned shift)
{
pgtable_free(table, shift);
}
-static inline void pte_free_finish(void) { }
+static inline void pte_free_finish(struct mmu_gather *tlb) { }
#endif /* !CONFIG_SMP */
static inline void __pte_free_tlb(struct mmu_gather *tlb, struct page *ptepage,
diff --git a/arch/powerpc/include/asm/thread_info.h b/arch/powerpc/include/asm/thread_info.h
index d8529ef..37c353e 100644
--- a/arch/powerpc/include/asm/thread_info.h
+++ b/arch/powerpc/include/asm/thread_info.h
@@ -139,10 +139,12 @@
#define TLF_NAPPING 0 /* idle thread enabled NAP mode */
#define TLF_SLEEPING 1 /* suspend code enabled SLEEP mode */
#define TLF_RESTORE_SIGMASK 2 /* Restore signal mask in do_signal */
+#define TLF_LAZY_MMU 3 /* tlb_batch is active */
#define _TLF_NAPPING (1 << TLF_NAPPING)
#define _TLF_SLEEPING (1 << TLF_SLEEPING)
#define _TLF_RESTORE_SIGMASK (1 << TLF_RESTORE_SIGMASK)
+#define _TLF_LAZY_MMU (1 << TLF_LAZY_MMU)
#ifndef __ASSEMBLY__
#define HAVE_SET_RESTORE_SIGMASK 1
diff --git a/arch/powerpc/include/asm/tlb.h b/arch/powerpc/include/asm/tlb.h
index e2b428b..8f0ed7a 100644
--- a/arch/powerpc/include/asm/tlb.h
+++ b/arch/powerpc/include/asm/tlb.h
@@ -28,6 +28,16 @@
#define tlb_start_vma(tlb, vma) do { } while (0)
#define tlb_end_vma(tlb, vma) do { } while (0)
+#define HAVE_ARCH_MMU_GATHER 1
+
+struct pte_freelist_batch;
+
+struct arch_mmu_gather {
+ struct pte_freelist_batch *batch;
+};
+
+#define ARCH_MMU_GATHER_INIT (struct arch_mmu_gather){ .batch = NULL, }
+
extern void tlb_flush(struct mmu_gather *tlb);
/* Get the generic bits... */
diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
index 095043d..91e52df 100644
--- a/arch/powerpc/kernel/process.c
+++ b/arch/powerpc/kernel/process.c
@@ -395,6 +395,9 @@
struct thread_struct *new_thread, *old_thread;
unsigned long flags;
struct task_struct *last;
+#ifdef CONFIG_PPC_BOOK3S_64
+ struct ppc64_tlb_batch *batch;
+#endif
#ifdef CONFIG_SMP
/* avoid complexity of lazy save/restore of fpu
@@ -513,7 +516,17 @@
old_thread->accum_tb += (current_tb - start_tb);
new_thread->start_tb = current_tb;
}
-#endif
+#endif /* CONFIG_PPC64 */
+
+#ifdef CONFIG_PPC_BOOK3S_64
+ batch = &__get_cpu_var(ppc64_tlb_batch);
+ if (batch->active) {
+ current_thread_info()->local_flags |= _TLF_LAZY_MMU;
+ if (batch->index)
+ __flush_tlb_pending(batch);
+ batch->active = 0;
+ }
+#endif /* CONFIG_PPC_BOOK3S_64 */
local_irq_save(flags);
@@ -528,6 +541,14 @@
hard_irq_disable();
last = _switch(old_thread, new_thread);
+#ifdef CONFIG_PPC_BOOK3S_64
+ if (current_thread_info()->local_flags & _TLF_LAZY_MMU) {
+ current_thread_info()->local_flags &= ~_TLF_LAZY_MMU;
+ batch = &__get_cpu_var(ppc64_tlb_batch);
+ batch->active = 1;
+ }
+#endif /* CONFIG_PPC_BOOK3S_64 */
+
local_irq_restore(flags);
return last;
diff --git a/arch/powerpc/mm/pgtable.c b/arch/powerpc/mm/pgtable.c
index 6a3997f..6e72788 100644
--- a/arch/powerpc/mm/pgtable.c
+++ b/arch/powerpc/mm/pgtable.c
@@ -33,8 +33,6 @@
#include "mmu_decl.h"
-DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
-
#ifdef CONFIG_SMP
/*
@@ -43,7 +41,6 @@
* freeing a page table page that is being walked without locks
*/
-static DEFINE_PER_CPU(struct pte_freelist_batch *, pte_freelist_cur);
static unsigned long pte_freelist_forced_free;
struct pte_freelist_batch
@@ -97,12 +94,10 @@
void pgtable_free_tlb(struct mmu_gather *tlb, void *table, unsigned shift)
{
- /* This is safe since tlb_gather_mmu has disabled preemption */
- struct pte_freelist_batch **batchp = &__get_cpu_var(pte_freelist_cur);
+ struct pte_freelist_batch **batchp = &tlb->arch.batch;
unsigned long pgf;
- if (atomic_read(&tlb->mm->mm_users) < 2 ||
- cpumask_equal(mm_cpumask(tlb->mm), cpumask_of(smp_processor_id()))){
+ if (atomic_read(&tlb->mm->mm_users) < 2) {
pgtable_free(table, shift);
return;
}
@@ -124,10 +119,9 @@
}
}
-void pte_free_finish(void)
+void pte_free_finish(struct mmu_gather *tlb)
{
- /* This is safe since tlb_gather_mmu has disabled preemption */
- struct pte_freelist_batch **batchp = &__get_cpu_var(pte_freelist_cur);
+ struct pte_freelist_batch **batchp = &tlb->arch.batch;
if (*batchp == NULL)
return;
diff --git a/arch/powerpc/mm/tlb_hash32.c b/arch/powerpc/mm/tlb_hash32.c
index 690566b..d555cdb 100644
--- a/arch/powerpc/mm/tlb_hash32.c
+++ b/arch/powerpc/mm/tlb_hash32.c
@@ -73,7 +73,7 @@
}
/* Push out batch of freed page tables */
- pte_free_finish();
+ pte_free_finish(tlb);
}
/*
diff --git a/arch/powerpc/mm/tlb_hash64.c b/arch/powerpc/mm/tlb_hash64.c
index c14d09f..5c94ca3 100644
--- a/arch/powerpc/mm/tlb_hash64.c
+++ b/arch/powerpc/mm/tlb_hash64.c
@@ -155,7 +155,7 @@
void tlb_flush(struct mmu_gather *tlb)
{
- struct ppc64_tlb_batch *tlbbatch = &__get_cpu_var(ppc64_tlb_batch);
+ struct ppc64_tlb_batch *tlbbatch = &get_cpu_var(ppc64_tlb_batch);
/* If there's a TLB batch pending, then we must flush it because the
* pages are going to be freed and we really don't want to have a CPU
@@ -164,8 +164,10 @@
if (tlbbatch->index)
__flush_tlb_pending(tlbbatch);
+ put_cpu_var(ppc64_tlb_batch);
+
/* Push out batch of freed page tables */
- pte_free_finish();
+ pte_free_finish(tlb);
}
/**
diff --git a/arch/powerpc/mm/tlb_nohash.c b/arch/powerpc/mm/tlb_nohash.c
index 2a030d8..8eaf67d 100644
--- a/arch/powerpc/mm/tlb_nohash.c
+++ b/arch/powerpc/mm/tlb_nohash.c
@@ -301,7 +301,7 @@
flush_tlb_mm(tlb->mm);
/* Push out batch of freed page tables */
- pte_free_finish();
+ pte_free_finish(tlb);
}
/*