---

yaml
---
r: 351207
b: refs/heads/master
c: 0fbebed
h: refs/heads/master
i:
  351205: a70b3de
  351203: ee12be6
  351199: 2428105
v: v3

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: bcd896bae0166b4443503482a26ecf84d9ba60ab
+refs/heads/master: 0fbebed682ff2788dee58e8d7f7dda46e33aa10b

trunk/arch/sparc/include/asm/hugetlb.h

@@ -12,7 +12,6 @@ pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr,
 
 static inline void hugetlb_prefault_arch_hook(struct mm_struct *mm)
 {
-	hugetlb_setup(mm);
 }
 
 static inline int is_hugepage_only_range(struct mm_struct *mm,

trunk/arch/sparc/include/asm/page_64.h

@@ -27,8 +27,8 @@
 #ifndef __ASSEMBLY__
 
 #if defined(CONFIG_HUGETLB_PAGE) || defined(CONFIG_TRANSPARENT_HUGEPAGE)
-struct mm_struct;
-extern void hugetlb_setup(struct mm_struct *mm);
+struct pt_regs;
+extern void hugetlb_setup(struct pt_regs *regs);
 #endif
 
 #define WANT_PAGE_VIRTUAL

trunk/arch/sparc/kernel/tsb.S

@@ -136,12 +136,43 @@ tsb_miss_page_table_walk_sun4v_fastpath:
 	 nop
 
 	/* It is a huge page, use huge page TSB entry address we
-	 * calculated above.
+	 * calculated above.  If the huge page TSB has not been
+	 * allocated, setup a trap stack and call hugetlb_setup()
+	 * to do so, then return from the trap to replay the TLB
+	 * miss.
+	 *
+	 * This is necessary to handle the case of transparent huge
+	 * pages where we don't really have a non-atomic context
+	 * in which to allocate the hugepage TSB hash table.  When
+	 * the 'mm' faults in the hugepage for the first time, we
+	 * thus handle it here.  This also makes sure that we can
+	 * allocate the TSB hash table on the correct NUMA node.
 	 */
 	TRAP_LOAD_TRAP_BLOCK(%g7, %g2)
-	ldx		[%g7 + TRAP_PER_CPU_TSB_HUGE_TEMP], %g2
-	cmp		%g2, -1
-	movne		%xcc, %g2, %g1
+	ldx		[%g7 + TRAP_PER_CPU_TSB_HUGE_TEMP], %g1
+	cmp		%g1, -1
+	bne,pt		%xcc, 60f
+	 nop
+
+661:	rdpr		%pstate, %g5
+	wrpr		%g5, PSTATE_AG | PSTATE_MG, %pstate
+	.section	.sun4v_2insn_patch, "ax"
+	.word		661b
+	SET_GL(1)
+	nop
+	.previous
+
+	rdpr	%tl, %g3
+	cmp	%g3, 1
+	bne,pn	%xcc, winfix_trampoline
+	 nop
+	ba,pt	%xcc, etrap
+	 rd	%pc, %g7
+	call	hugetlb_setup
+	 add	%sp, PTREGS_OFF, %o0
+	ba,pt	%xcc, rtrap
+	 nop
+
 60:
 #endif
 

trunk/arch/sparc/mm/fault_64.c

@@ -472,8 +472,13 @@ asmlinkage void __kprobes do_sparc64_fault(struct pt_regs *regs)
 #if defined(CONFIG_HUGETLB_PAGE) || defined(CONFIG_TRANSPARENT_HUGEPAGE)
 	mm_rss = mm->context.huge_pte_count;
 	if (unlikely(mm_rss >
-		     mm->context.tsb_block[MM_TSB_HUGE].tsb_rss_limit))
-		tsb_grow(mm, MM_TSB_HUGE, mm_rss);
+		     mm->context.tsb_block[MM_TSB_HUGE].tsb_rss_limit)) {
+		if (mm->context.tsb_block[MM_TSB_HUGE].tsb)
+			tsb_grow(mm, MM_TSB_HUGE, mm_rss);
+		else
+			hugetlb_setup(regs);
+
+	}
 #endif
 	return;
 

trunk/arch/sparc/mm/init_64.c

@@ -2718,14 +2718,28 @@ static void context_reload(void *__data)
 		load_secondary_context(mm);
 }
 
-void hugetlb_setup(struct mm_struct *mm)
+void hugetlb_setup(struct pt_regs *regs)
 {
-	struct tsb_config *tp = &mm->context.tsb_block[MM_TSB_HUGE];
+	struct mm_struct *mm = current->mm;
+	struct tsb_config *tp;
 
-	if (likely(tp->tsb != NULL))
-		return;
+	if (in_atomic() || !mm) {
+		const struct exception_table_entry *entry;
+
+		entry = search_exception_tables(regs->tpc);
+		if (entry) {
+			regs->tpc = entry->fixup;
+			regs->tnpc = regs->tpc + 4;
+			return;
+		}
+		pr_alert("Unexpected HugeTLB setup in atomic context.\n");
+		die_if_kernel("HugeTSB in atomic", regs);
+	}
+
+	tp = &mm->context.tsb_block[MM_TSB_HUGE];
+	if (likely(tp->tsb == NULL))
+		tsb_grow(mm, MM_TSB_HUGE, 0);
 
-	tsb_grow(mm, MM_TSB_HUGE, 0);
 	tsb_context_switch(mm);
 	smp_tsb_sync(mm);
 

trunk/arch/sparc/mm/tlb.c

@@ -135,8 +135,15 @@ void set_pmd_at(struct mm_struct *mm, unsigned long addr,
 			mm->context.huge_pte_count++;
 		else
 			mm->context.huge_pte_count--;
-		if (mm->context.huge_pte_count == 1)
-			hugetlb_setup(mm);
+
+		/* Do not try to allocate the TSB hash table if we
+		 * don't have one already.  We have various locks held
+		 * and thus we'll end up doing a GFP_KERNEL allocation
+		 * in an atomic context.
+		 *
+		 * Instead, we let the first TLB miss on a hugepage
+		 * take care of this.
+		 */
 	}
 
 	if (!pmd_none(orig)) {