xen/trace: add ptpage alloc/release tracepoints

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>

arch/x86/xen/mmu.c

@@ -1478,8 +1478,11 @@ static void __init xen_release_pmd_init(unsigned long pfn)
 static void xen_alloc_ptpage(struct mm_struct *mm, unsigned long pfn, unsigned level)
 {
 	struct page *page = pfn_to_page(pfn);
+	int pinned = PagePinned(virt_to_page(mm->pgd));
  
-	if (PagePinned(virt_to_page(mm->pgd))) {
+	trace_xen_mmu_alloc_ptpage(mm, pfn, level, pinned);
+
+	if (pinned) {
 		SetPagePinned(page);
 
 		if (!PageHighMem(page)) {
@@ -1508,8 +1511,11 @@ static void xen_alloc_pmd(struct mm_struct *mm, unsigned long pfn)
 static void xen_release_ptpage(unsigned long pfn, unsigned level)
 {
 	struct page *page = pfn_to_page(pfn);
+	bool pinned = PagePinned(page);
+
+	trace_xen_mmu_release_ptpage(pfn, level, pinned);
 
-	if (PagePinned(page)) {
+	if (pinned) {
 		if (!PageHighMem(page)) {
 			if (level == PT_PTE && USE_SPLIT_PTLOCKS)
 				pin_pagetable_pfn(MMUEXT_UNPIN_TABLE, pfn);

include/trace/events/xen.h

@@ -347,6 +347,39 @@ TRACE_EVENT(xen_mmu_ptep_modify_prot_commit,
 		      (int)sizeof(pteval_t) * 2, (unsigned long long)__entry->pteval)
 	);
 
+TRACE_EVENT(xen_mmu_alloc_ptpage,
+	    TP_PROTO(struct mm_struct *mm, unsigned long pfn, unsigned level, bool pinned),
+	    TP_ARGS(mm, pfn, level, pinned),
+	    TP_STRUCT__entry(
+		    __field(struct mm_struct *, mm)
+		    __field(unsigned long, pfn)
+		    __field(unsigned, level)
+		    __field(bool, pinned)
+		    ),
+	    TP_fast_assign(__entry->mm = mm;
+			   __entry->pfn = pfn;
+			   __entry->level = level;
+			   __entry->pinned = pinned),
+	    TP_printk("mm %p  pfn %lx  level %d  %spinned",
+		      __entry->mm, __entry->pfn, __entry->level,
+		      __entry->pinned ? "" : "un")
+	);
+
+TRACE_EVENT(xen_mmu_release_ptpage,
+	    TP_PROTO(unsigned long pfn, unsigned level, bool pinned),
+	    TP_ARGS(pfn, level, pinned),
+	    TP_STRUCT__entry(
+		    __field(unsigned long, pfn)
+		    __field(unsigned, level)
+		    __field(bool, pinned)
+		    ),
+	    TP_fast_assign(__entry->pfn = pfn;
+			   __entry->level = level;
+			   __entry->pinned = pinned),
+	    TP_printk("pfn %lx  level %d  %spinned",
+		      __entry->pfn, __entry->level,
+		      __entry->pinned ? "" : "un")
+	);
 
 #endif /*  _TRACE_XEN_H */