diff --git a/sys/amd64/amd64/pmap.c b/sys/amd64/amd64/pmap.c
--- a/sys/amd64/amd64/pmap.c
+++ b/sys/amd64/amd64/pmap.c
@@ -8155,9 +8155,16 @@
 void
 pmap_zero_page(vm_page_t m)
 {
-	vm_offset_t va = PHYS_TO_DMAP(VM_PAGE_TO_PHYS(m));
+	vm_offset_t va;
 
+#ifdef TSLOG_PAGEZERO
+	TSENTER();
+#endif
+	va = PHYS_TO_DMAP(VM_PAGE_TO_PHYS(m));
 	pagezero((void *)va);
+#ifdef TSLOG_PAGEZERO
+	TSEXIT();
+#endif
 }
 
 /*
diff --git a/sys/conf/NOTES b/sys/conf/NOTES
--- a/sys/conf/NOTES
+++ b/sys/conf/NOTES
@@ -615,6 +615,9 @@
 # before it is possible to use more sophisticated tools like DTrace.
 # The TSLOGSIZE option controls the size of the (preallocated, fixed
 # length) buffer used for storing these events (default: 262144 records).
+# The TSLOG_PAGEZERO option enables TSLOG of pmap_zero_page; this must be
+# enabled separately since it typically generates too many records to be
+# useful.
 #
 # For security reasons the TSLOG option should not be enabled on systems
 # used in production.
diff --git a/sys/conf/options b/sys/conf/options
--- a/sys/conf/options
+++ b/sys/conf/options
@@ -67,6 +67,7 @@
 TEXTDUMP_PREFERRED	opt_ddb.h
 TEXTDUMP_VERBOSE	opt_ddb.h
 TSLOG	opt_global.h
+TSLOG_PAGEZERO	opt_global.h
 TSLOGSIZE	opt_global.h
 
 # Miscellaneous options.