mm-tracepoint: rename page-free events

Rename mm_page_free_direct into mm_page_free and mm_pagevec_free into
mm_page_free_batched

Since v2.6.33-5426-gc475dab the kernel triggers mm_page_free_direct for
all freed pages, not only for directly freed. So, let's name it properly.
For pages freed via page-list we also trigger mm_page_free_batched event.

Signed-off-by: Konstantin Khlebnikov <[e-mail]>
Cc: Mel Gorman <[e-mail]>
Cc: KOSAKI Motohiro <[e-mail]>
Reviewed-by: Minchan Kim <[e-mail]>
Cc: Hugh Dickins <[e-mail]>
Signed-off-by: Andrew Morton <[e-mail]>
Signed-off-by: Linus Torvalds <[e-mail]>

Documentation/trace/events-kmem.txt

···
 ==================
 mm_page_alloc		  page=%p pfn=%lu order=%d migratetype=%d gfp_flags=%s
 mm_page_alloc_zone_locked page=%p pfn=%lu order=%u migratetype=%d cpu=%d percpu_refill=%d
-mm_page_free_direct	  page=%p pfn=%lu order=%d
-mm_pagevec_free		  page=%p pfn=%lu order=%d cold=%d
+mm_page_free		  page=%p pfn=%lu order=%d
+mm_page_free_batched	  page=%p pfn=%lu order=%d cold=%d
 
 These four events deal with page allocation and freeing. mm_page_alloc is
 a simple indicator of page allocator activity. Pages may be allocated from
···
 impairs performance by disabling interrupts, dirtying cache lines between
 CPUs and serialising many CPUs.
 
-When a page is freed directly by the caller, the mm_page_free_direct event
+When a page is freed directly by the caller, the only mm_page_free event
 is triggered. Significant amounts of activity here could indicate that the
 callers should be batching their activities.
 
-When pages are freed using a pagevec, the mm_pagevec_free is
-triggered. Broadly speaking, pages are taken off the LRU lock in bulk and
-freed in batch with a pagevec. Significant amounts of activity here could
+When pages are freed in batch, the also mm_page_free_batched is triggered.
+Broadly speaking, pages are taken off the LRU lock in bulk and
+freed in batch with a page list. Significant amounts of activity here could
 indicate that the system is under memory pressure and can also indicate
 contention on the zone->lru_lock.
 

Documentation/trace/postprocess/trace-pagealloc-postprocess.pl

···
 
 # Tracepoint events
 use constant MM_PAGE_ALLOC		=> 1;
-use constant MM_PAGE_FREE_DIRECT 	=> 2;
-use constant MM_PAGEVEC_FREE		=> 3;
+use constant MM_PAGE_FREE		=> 2;
+use constant MM_PAGE_FREE_BATCHED	=> 3;
 use constant MM_PAGE_PCPU_DRAIN		=> 4;
 use constant MM_PAGE_ALLOC_ZONE_LOCKED	=> 5;
 use constant MM_PAGE_ALLOC_EXTFRAG	=> 6;
···
 		# Perl Switch() sucks majorly
 		if ($tracepoint eq "mm_page_alloc") {
 			$perprocesspid{$process_pid}->{MM_PAGE_ALLOC}++;
-		} elsif ($tracepoint eq "mm_page_free_direct") {
-			$perprocesspid{$process_pid}->{MM_PAGE_FREE_DIRECT}++;
-		} elsif ($tracepoint eq "mm_pagevec_free") {
-			$perprocesspid{$process_pid}->{MM_PAGEVEC_FREE}++;
+		} elsif ($tracepoint eq "mm_page_free") {
+			$perprocesspid{$process_pid}->{MM_PAGE_FREE}++
+		} elsif ($tracepoint eq "mm_page_free_batched") {
+			$perprocesspid{$process_pid}->{MM_PAGE_FREE_BATCHED}++;
 		} elsif ($tracepoint eq "mm_page_pcpu_drain") {
 			$perprocesspid{$process_pid}->{MM_PAGE_PCPU_DRAIN}++;
 			$perprocesspid{$process_pid}->{STATE_PCPU_PAGES_DRAINED}++;
···
 			$process_pid,
 			$stats{$process_pid}->{MM_PAGE_ALLOC},
 			$stats{$process_pid}->{MM_PAGE_ALLOC_ZONE_LOCKED},
-			$stats{$process_pid}->{MM_PAGE_FREE_DIRECT},
-			$stats{$process_pid}->{MM_PAGEVEC_FREE},
+			$stats{$process_pid}->{MM_PAGE_FREE},
+			$stats{$process_pid}->{MM_PAGE_FREE_BATCHED},
 			$stats{$process_pid}->{MM_PAGE_PCPU_DRAIN},
 			$stats{$process_pid}->{HIGH_PCPU_DRAINS},
 			$stats{$process_pid}->{HIGH_PCPU_REFILLS},
···
 
 		$perprocess{$process}->{MM_PAGE_ALLOC} += $perprocesspid{$process_pid}->{MM_PAGE_ALLOC};
 		$perprocess{$process}->{MM_PAGE_ALLOC_ZONE_LOCKED} += $perprocesspid{$process_pid}->{MM_PAGE_ALLOC_ZONE_LOCKED};
-		$perprocess{$process}->{MM_PAGE_FREE_DIRECT} += $perprocesspid{$process_pid}->{MM_PAGE_FREE_DIRECT};
-		$perprocess{$process}->{MM_PAGEVEC_FREE} += $perprocesspid{$process_pid}->{MM_PAGEVEC_FREE};
+		$perprocess{$process}->{MM_PAGE_FREE} += $perprocesspid{$process_pid}->{MM_PAGE_FREE};
+		$perprocess{$process}->{MM_PAGE_FREE_BATCHED} += $perprocesspid{$process_pid}->{MM_PAGE_FREE_BATCHED};
 		$perprocess{$process}->{MM_PAGE_PCPU_DRAIN} += $perprocesspid{$process_pid}->{MM_PAGE_PCPU_DRAIN};
 		$perprocess{$process}->{HIGH_PCPU_DRAINS} += $perprocesspid{$process_pid}->{HIGH_PCPU_DRAINS};
 		$perprocess{$process}->{HIGH_PCPU_REFILLS} += $perprocesspid{$process_pid}->{HIGH_PCPU_REFILLS};

include/trace/events/kmem.h

···
 	TP_ARGS(call_site, ptr)
 );
 
-TRACE_EVENT(mm_page_free_direct,
+TRACE_EVENT(mm_page_free,
 
 	TP_PROTO(struct page *page, unsigned int order),
 
···
 			__entry->order)
 );
 
-TRACE_EVENT(mm_pagevec_free,
+TRACE_EVENT(mm_page_free_batched,
 
 	TP_PROTO(struct page *page, int cold),
 

mm/page_alloc.c

···
 	int i;
 	int bad = 0;
 
-	trace_mm_page_free_direct(page, order);
+	trace_mm_page_free(page, order);
 	kmemcheck_free_shadow(page, order);
 
 	if (PageAnon(page))
···
 	struct page *page, *next;
 
 	list_for_each_entry_safe(page, next, list, lru) {
-		trace_mm_pagevec_free(page, cold);
+		trace_mm_page_free_batched(page, cold);
 		free_hot_cold_page(page, cold);
 	}
 }