[Patch] mm tracepoints

[Patch] mm tracepoints

[Larry Woodman]

[-- Attachment #1: Type: text/plain, Size: 1145 bytes --]

I've implemented several mm tracepoints to track page allocation and
freeing, various types of pagefaults and unmaps, and critical page
reclamation routines.  This is useful for debugging memory allocation
issues and system performance problems under heavy memory loads.
Thoughts?:

# tracer: mm
#
#           TASK-PID    CPU#    TIMESTAMP  FUNCTION
#              | |       |          |         |
         pdflush-624   [004]   184.293169: wb_kupdate:
(mm_pdflush_kupdate) count=3e48
         pdflush-624   [004]   184.293439: get_page_from_freelist:
(mm_page_allocation) pfn=447c27 zone_free=1940910
        events/6-33    [006]   184.962879: free_hot_cold_page:
(mm_page_free) pfn=44bba9
      irqbalance-8313  [001]   188.042951: unmap_vmas:
(mm_anon_userfree) mm=ffff88044a7300c0 address=7f9a2eb70000 pfn=24c29a
             cat-9122  [005]   191.141173: filemap_fault:
(mm_filemap_fault) primary fault: mm=ffff88024c9d8f40 address=3cea2dd000
pfn=44d68e
             cat-9122  [001]   191.143036: handle_mm_fault:
(mm_anon_fault) mm=ffff88024c8beb40 address=7fffbde99f94 pfn=24ce22
...



Signed-off-by: Larry Woodman <lwoodman@redhat.com>

[-- Attachment #2: upstream-mm_tracepoints.patch --]
[-- Type: text/x-patch, Size: 21557 bytes --]

--- linux-2.6-tip/mm/memory.c.orig	2009-03-16 12:05:59.000000000 -0400
+++ linux-2.6-tip/mm/memory.c	2009-03-16 12:10:49.000000000 -0400
@@ -57,6 +57,7 @@
 #include <linux/kallsyms.h>
 #include <linux/swapops.h>
 #include <linux/elf.h>
+#include <trace/mm.h>
 
 #include <asm/pgalloc.h>
 #include <asm/uaccess.h>
@@ -768,6 +769,8 @@ int copy_page_range(struct mm_struct *ds
 	return ret;
 }
 
+DEFINE_TRACE(mm_anon_userfree);
+DEFINE_TRACE(mm_filemap_userunmap);
 static unsigned long zap_pte_range(struct mmu_gather *tlb,
 				struct vm_area_struct *vma, pmd_t *pmd,
 				unsigned long addr, unsigned long end,
@@ -822,15 +825,19 @@ static unsigned long zap_pte_range(struc
 						addr) != page->index)
 				set_pte_at(mm, addr, pte,
 					   pgoff_to_pte(page->index));
-			if (PageAnon(page))
+			if (PageAnon(page)) {
 				anon_rss--;
-			else {
+				trace_mm_anon_userfree(mm, addr,
+							page_to_pfn(page));
+			} else {
 				if (pte_dirty(ptent))
 					set_page_dirty(page);
 				if (pte_young(ptent) &&
 				    likely(!VM_SequentialReadHint(vma)))
 					mark_page_accessed(page);
 				file_rss--;
+				trace_mm_filemap_userunmap(mm, addr,
+							page_to_pfn(page));
 			}
 			page_remove_rmap(page);
 			if (unlikely(page_mapcount(page) < 0))
@@ -1879,6 +1886,8 @@ static inline void cow_user_page(struct 
 		copy_user_highpage(dst, src, va, vma);
 }
 
+DEFINE_TRACE(mm_anon_cow);
+DEFINE_TRACE(mm_filemap_cow);
 /*
  * This routine handles present pages, when users try to write
  * to a shared page. It is done by copying the page to a new address
@@ -1901,7 +1910,7 @@ static int do_wp_page(struct mm_struct *
 		unsigned long address, pte_t *page_table, pmd_t *pmd,
 		spinlock_t *ptl, pte_t orig_pte)
 {
-	struct page *old_page, *new_page;
+	struct page *old_page, *new_page = NULL;
 	pte_t entry;
 	int reuse = 0, ret = 0;
 	int page_mkwrite = 0;
@@ -2031,9 +2040,14 @@ gotten:
 			if (!PageAnon(old_page)) {
 				dec_mm_counter(mm, file_rss);
 				inc_mm_counter(mm, anon_rss);
+				trace_mm_filemap_cow(mm, address,
+					page_to_pfn(new_page));
 			}
-		} else
+		} else {
 			inc_mm_counter(mm, anon_rss);
+			trace_mm_anon_cow(mm, address,
+					page_to_pfn(new_page));
+		}
 		flush_cache_page(vma, address, pte_pfn(orig_pte));
 		entry = mk_pte(new_page, vma->vm_page_prot);
 		entry = maybe_mkwrite(pte_mkdirty(entry), vma);
@@ -2398,6 +2412,7 @@ int vmtruncate_range(struct inode *inode
 	return 0;
 }
 
+DEFINE_TRACE(mm_anon_pgin);
 /*
  * We enter with non-exclusive mmap_sem (to exclude vma changes,
  * but allow concurrent faults), and pte mapped but not yet locked.
@@ -2511,6 +2526,7 @@ static int do_swap_page(struct mm_struct
 unlock:
 	pte_unmap_unlock(page_table, ptl);
 out:
+	trace_mm_anon_pgin(mm, address, page_to_pfn(page));
 	return ret;
 out_nomap:
 	mem_cgroup_cancel_charge_swapin(ptr);
@@ -2520,6 +2536,7 @@ out_nomap:
 	return ret;
 }
 
+DEFINE_TRACE(mm_anon_fault);
 /*
  * We enter with non-exclusive mmap_sem (to exclude vma changes,
  * but allow concurrent faults), and pte mapped but not yet locked.
@@ -2543,6 +2560,7 @@ static int do_anonymous_page(struct mm_s
 		goto oom;
 	__SetPageUptodate(page);
 
+	trace_mm_anon_fault(mm, address, page_to_pfn(page));
 	if (mem_cgroup_newpage_charge(page, mm, GFP_KERNEL))
 		goto oom_free_page;
 
--- linux-2.6-tip/mm/rmap.c.orig	2009-03-16 12:05:59.000000000 -0400
+++ linux-2.6-tip/mm/rmap.c	2009-03-16 12:10:49.000000000 -0400
@@ -50,6 +50,7 @@
 #include <linux/memcontrol.h>
 #include <linux/mmu_notifier.h>
 #include <linux/migrate.h>
+#include <trace/mm.h>
 
 #include <asm/tlbflush.h>
 
@@ -978,6 +979,7 @@ static int try_to_mlock_page(struct page
 	return mlocked;
 }
 
+DEFINE_TRACE(mm_anon_unmap);
 /**
  * try_to_unmap_anon - unmap or unlock anonymous page using the object-based
  * rmap method
@@ -1034,9 +1036,11 @@ static int try_to_unmap_anon(struct page
 	else if (ret == SWAP_MLOCK)
 		ret = SWAP_AGAIN;	/* saw VM_LOCKED vma */
 
+	trace_mm_anon_unmap(page_to_pfn(page), ret == SWAP_SUCCESS);
 	return ret;
 }
 
+DEFINE_TRACE(mm_filemap_unmap);
 /**
  * try_to_unmap_file - unmap/unlock file page using the object-based rmap method
  * @page: the page to unmap/unlock
@@ -1170,6 +1174,7 @@ out:
 		ret = SWAP_MLOCK;	/* actually mlocked the page */
 	else if (ret == SWAP_MLOCK)
 		ret = SWAP_AGAIN;	/* saw VM_LOCKED vma */
+	trace_mm_filemap_unmap(page_to_pfn(page), ret == SWAP_SUCCESS);
 	return ret;
 }
 
--- linux-2.6-tip/mm/page_alloc.c.orig	2009-03-16 12:05:59.000000000 -0400
+++ linux-2.6-tip/mm/page_alloc.c	2009-03-16 12:10:49.000000000 -0400
@@ -47,6 +47,7 @@
 #include <linux/page-isolation.h>
 #include <linux/page_cgroup.h>
 #include <linux/debugobjects.h>
+#include <trace/mm.h>
 
 #include <asm/tlbflush.h>
 #include <asm/div64.h>
@@ -994,6 +995,7 @@ void mark_free_pages(struct zone *zone)
 }
 #endif /* CONFIG_PM */
 
+DEFINE_TRACE(mm_page_free);
 /*
  * Free a 0-order page
  */
@@ -1010,6 +1012,7 @@ static void free_hot_cold_page(struct pa
 	if (free_pages_check(page))
 		return;
 
+	trace_mm_page_free(page_to_pfn(page));
 	if (!PageHighMem(page)) {
 		debug_check_no_locks_freed(page_address(page), PAGE_SIZE);
 		debug_check_no_obj_freed(page_address(page), PAGE_SIZE);
@@ -1399,6 +1402,7 @@ static void zlc_mark_zone_full(struct zo
 }
 #endif	/* CONFIG_NUMA */
 
+DEFINE_TRACE(mm_page_allocation);
 /*
  * get_page_from_freelist goes through the zonelist trying to allocate
  * a page.
@@ -1453,8 +1457,11 @@ zonelist_scan:
 		}
 
 		page = buffered_rmqueue(preferred_zone, zone, order, gfp_mask);
-		if (page)
+		if (page) {
+			trace_mm_page_allocation(page_to_pfn(page),
+					zone_page_state(zone, NR_FREE_PAGES));
 			break;
+		}
 this_zone_full:
 		if (NUMA_BUILD)
 			zlc_mark_zone_full(zonelist, z);
--- linux-2.6-tip/mm/vmscan.c.orig	2009-03-16 12:05:59.000000000 -0400
+++ linux-2.6-tip/mm/vmscan.c	2009-03-16 12:10:49.000000000 -0400
@@ -40,6 +40,7 @@
 #include <linux/memcontrol.h>
 #include <linux/delayacct.h>
 #include <linux/sysctl.h>
+#include <trace/mm.h>
 
 #include <asm/tlbflush.h>
 #include <asm/div64.h>
@@ -329,6 +330,7 @@ typedef enum {
 	PAGE_CLEAN,
 } pageout_t;
 
+DEFINE_TRACE(mm_pagereclaim_pgout);
 /*
  * pageout is called by shrink_page_list() for each dirty page.
  * Calls ->writepage().
@@ -407,6 +409,7 @@ static pageout_t pageout(struct page *pa
 			ClearPageReclaim(page);
 		}
 		inc_zone_page_state(page, NR_VMSCAN_WRITE);
+		trace_mm_pagereclaim_pgout(page_to_pfn(page), PageAnon(page));
 		return PAGE_SUCCESS;
 	}
 
@@ -570,6 +573,9 @@ void putback_lru_page(struct page *page)
 #endif /* CONFIG_UNEVICTABLE_LRU */
 
 
+DEFINE_TRACE(mm_pagereclaim_free);
+DEFINE_TRACE(mm_pagereclaim_shrinkinactive_i2a);
+DEFINE_TRACE(mm_pagereclaim_shrinkinactive_i2i);
 /*
  * shrink_page_list() returns the number of reclaimed pages
  */
@@ -758,6 +764,7 @@ free_it:
 			__pagevec_free(&freed_pvec);
 			pagevec_reinit(&freed_pvec);
 		}
+		trace_mm_pagereclaim_free(page_to_pfn(page), PageAnon(page));
 		continue;
 
 cull_mlocked:
@@ -774,10 +781,12 @@ activate_locked:
 		VM_BUG_ON(PageActive(page));
 		SetPageActive(page);
 		pgactivate++;
+		trace_mm_pagereclaim_shrinkinactive_i2a(page_to_pfn(page));
 keep_locked:
 		unlock_page(page);
 keep:
 		list_add(&page->lru, &ret_pages);
+		trace_mm_pagereclaim_shrinkinactive_i2i(page_to_pfn(page));
 		VM_BUG_ON(PageLRU(page) || PageUnevictable(page));
 	}
 	list_splice(&ret_pages, page_list);
@@ -1036,6 +1045,7 @@ int isolate_lru_page(struct page *page)
 	return ret;
 }
 
+DEFINE_TRACE(mm_pagereclaim_shrinkinactive);
 /*
  * shrink_inactive_list() is a helper for shrink_zone().  It returns the number
  * of reclaimed pages
@@ -1170,6 +1180,7 @@ static unsigned long shrink_inactive_lis
 done:
 	local_irq_enable();
 	pagevec_release(&pvec);
+	trace_mm_pagereclaim_shrinkinactive(nr_reclaimed);
 	return nr_reclaimed;
 }
 
@@ -1187,6 +1198,9 @@ static inline void note_zone_scanning_pr
 		zone->prev_priority = priority;
 }
 
+DEFINE_TRACE(mm_pagereclaim_shrinkactive);
+DEFINE_TRACE(mm_pagereclaim_shrinkactive_a2a);
+DEFINE_TRACE(mm_pagereclaim_shrinkactive_a2i);
 /*
  * This moves pages from the active list to the inactive list.
  *
@@ -1247,6 +1261,7 @@ static void shrink_active_list(unsigned 
 
 		if (unlikely(!page_evictable(page, NULL))) {
 			putback_lru_page(page);
+			trace_mm_pagereclaim_shrinkactive_a2a(page_to_pfn(page));
 			continue;
 		}
 
@@ -1256,6 +1271,7 @@ static void shrink_active_list(unsigned 
 			pgmoved++;
 
 		list_add(&page->lru, &l_inactive);
+		trace_mm_pagereclaim_shrinkactive_a2i(page_to_pfn(page));
 	}
 
 	/*
@@ -1310,6 +1326,7 @@ static void shrink_active_list(unsigned 
 		pagevec_swap_free(&pvec);
 
 	pagevec_release(&pvec);
+	trace_mm_pagereclaim_shrinkactive(pgscanned);
 }
 
 static int inactive_anon_is_low_global(struct zone *zone)
@@ -1450,6 +1467,7 @@ static void get_scan_ratio(struct zone *
 }
 
 
+DEFINE_TRACE(mm_pagereclaim_shrinkzone);
 /*
  * This is a basic per-zone page freer.  Used by both kswapd and direct reclaim.
  */
@@ -1510,6 +1528,7 @@ static void shrink_zone(int priority, st
 	}
 
 	sc->nr_reclaimed = nr_reclaimed;
+	trace_mm_pagereclaim_shrinkzone(nr_reclaimed);
 
 	/*
 	 * Even if we did not try to evict anon pages at all, we want to
@@ -1521,6 +1540,7 @@ static void shrink_zone(int priority, st
 	throttle_vm_writeout(sc->gfp_mask);
 }
 
+DEFINE_TRACE(mm_directreclaim_reclaimall);
 /*
  * This is the direct reclaim path, for page-allocating processes.  We only
  * try to reclaim pages from zones which will satisfy the caller's allocation
@@ -1569,6 +1589,7 @@ static void shrink_zones(int priority, s
 							priority);
 		}
 
+		trace_mm_directreclaim_reclaimall(priority);
 		shrink_zone(priority, zone, sc);
 	}
 }
@@ -1732,6 +1753,7 @@ unsigned long try_to_free_mem_cgroup_pag
 }
 #endif
 
+DEFINE_TRACE(mm_kswapd_runs);
 /*
  * For kswapd, balance_pgdat() will work across all this node's zones until
  * they are all at pages_high.
@@ -1938,6 +1960,7 @@ out:
 		goto loop_again;
 	}
 
+	trace_mm_kswapd_runs(sc.nr_reclaimed);
 	return sc.nr_reclaimed;
 }
 
@@ -2278,6 +2301,7 @@ int sysctl_min_unmapped_ratio = 1;
  */
 int sysctl_min_slab_ratio = 5;
 
+DEFINE_TRACE(mm_directreclaim_reclaimzone);
 /*
  * Try to free up some pages from this zone through reclaim.
  */
@@ -2321,6 +2345,7 @@ static int __zone_reclaim(struct zone *z
 		do {
 			note_zone_scanning_priority(zone, priority);
 			shrink_zone(priority, zone, &sc);
+			trace_mm_directreclaim_reclaimzone(priority);
 			priority--;
 		} while (priority >= 0 && sc.nr_reclaimed < nr_pages);
 	}
@@ -2352,6 +2377,7 @@ static int __zone_reclaim(struct zone *z
 
 	p->reclaim_state = NULL;
 	current->flags &= ~(PF_MEMALLOC | PF_SWAPWRITE);
+	trace_mm_directreclaim_reclaimzone(sc.nr_reclaimed);
 	return sc.nr_reclaimed >= nr_pages;
 }
 
--- linux-2.6-tip/mm/filemap.c.orig	2009-03-16 12:05:59.000000000 -0400
+++ linux-2.6-tip/mm/filemap.c	2009-03-16 12:10:49.000000000 -0400
@@ -34,6 +34,7 @@
 #include <linux/hardirq.h> /* for BUG_ON(!in_atomic()) only */
 #include <linux/memcontrol.h>
 #include <linux/mm_inline.h> /* for page_is_file_cache() */
+#include <trace/mm.h>
 #include "internal.h"
 
 /*
@@ -1436,6 +1437,7 @@ static int page_cache_read(struct file *
 
 #define MMAP_LOTSAMISS  (100)
 
+DEFINE_TRACE(mm_filemap_fault);
 /**
  * filemap_fault - read in file data for page fault handling
  * @vma:	vma in which the fault was taken
@@ -1547,6 +1549,8 @@ retry_find:
 	 */
 	ra->prev_pos = (loff_t)page->index << PAGE_CACHE_SHIFT;
 	vmf->page = page;
+	trace_mm_filemap_fault(vma->vm_mm, (unsigned long)vmf->virtual_address,
+			page_to_pfn(page), vmf->flags&FAULT_FLAG_NONLINEAR);
 	return ret | VM_FAULT_LOCKED;
 
 no_cached_page:
--- linux-2.6-tip/mm/page-writeback.c.orig	2009-03-16 12:05:59.000000000 -0400
+++ linux-2.6-tip/mm/page-writeback.c	2009-03-16 12:10:49.000000000 -0400
@@ -34,6 +34,7 @@
 #include <linux/syscalls.h>
 #include <linux/buffer_head.h>
 #include <linux/pagevec.h>
+#include <trace/mm.h>
 
 /*
  * The maximum number of pages to writeout in a single bdflush/kupdate
@@ -677,6 +678,7 @@ void throttle_vm_writeout(gfp_t gfp_mask
         }
 }
 
+DEFINE_TRACE(mm_pdflush_bgwriteout);
 /*
  * writeback at least _min_pages, and keep writing until the amount of dirty
  * memory is less than the background threshold, or until we're all clean.
@@ -716,6 +718,7 @@ static void background_writeout(unsigned
 				break;
 		}
 	}
+	trace_mm_pdflush_bgwriteout(_min_pages);
 }
 
 /*
@@ -737,6 +740,7 @@ static void laptop_timer_fn(unsigned lon
 static DEFINE_TIMER(wb_timer, wb_timer_fn, 0, 0);
 static DEFINE_TIMER(laptop_mode_wb_timer, laptop_timer_fn, 0, 0);
 
+DEFINE_TRACE(mm_pdflush_kupdate);
 /*
  * Periodic writeback of "old" data.
  *
@@ -776,6 +780,7 @@ static void wb_kupdate(unsigned long arg
 	nr_to_write = global_page_state(NR_FILE_DIRTY) +
 			global_page_state(NR_UNSTABLE_NFS) +
 			(inodes_stat.nr_inodes - inodes_stat.nr_unused);
+	trace_mm_pdflush_kupdate(nr_to_write);
 	while (nr_to_write > 0) {
 		wbc.more_io = 0;
 		wbc.encountered_congestion = 0;
--- /dev/null	2009-03-01 15:15:06.452930698 -0500
+++ linux-2.6-tip/include/trace/mm_event_types.h	2009-03-16 12:10:49.000000000 -0400
@@ -0,0 +1,281 @@
+/* use <trace/mm.h> instead */
+#ifndef TRACE_FORMAT
+# error Do not include this file directly.
+# error Unless you know what you are doing.
+#endif
+
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM mm
+
+TRACE_EVENT_FORMAT(mm_anon_fault,
+	TPPROTO(struct mm_struct *mm, unsigned long address, unsigned long pfn),
+	TPARGS(mm, address, pfn),
+	TPFMT("mm=%lx address=%lx pfn=%lx", mm, address, pfn),
+	TRACE_STRUCT(
+		TRACE_FIELD(struct mm_struct *, mm, mm)
+		TRACE_FIELD(unsigned long, address, address)
+		TRACE_FIELD(unsigned long, pfn, pfn)
+	),
+	TPRAWFMT("mm %p address %lx pfn %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_anon_pgin,
+	TPPROTO(struct mm_struct *mm, unsigned long address, unsigned long pfn),
+	TPARGS(mm, address, pfn),
+	TPFMT("mm=%lx address=%lx pfn=%lx", mm, address, pfn),
+	TRACE_STRUCT(
+		TRACE_FIELD(struct mm_struct *, mm, mm)
+		TRACE_FIELD(unsigned long, address, address)
+		TRACE_FIELD(unsigned long, pfn, pfn)
+	),
+	TPRAWFMT("mm %p address %lx pfn %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_anon_cow,
+	TPPROTO(struct mm_struct *mm, unsigned long address, unsigned long pfn),
+	TPARGS(mm, address, pfn),
+	TPFMT("mm=%lx address=%lx pfn=%lx", mm, address, pfn),
+	TRACE_STRUCT(
+		TRACE_FIELD(struct mm_struct *, mm, mm)
+		TRACE_FIELD(unsigned long, address, address)
+		TRACE_FIELD(unsigned long, pfn, pfn)
+	),
+	TPRAWFMT("mm %p address %lx pfn %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_anon_userfree,
+	TPPROTO(struct mm_struct *mm, unsigned long address, unsigned long pfn),
+	TPARGS(mm, address, pfn),
+	TPFMT("mm=%lx address=%lx pfn=%lx", mm, address, pfn),
+	TRACE_STRUCT(
+		TRACE_FIELD(struct mm_struct *, mm, mm)
+		TRACE_FIELD(unsigned long, address, address)
+		TRACE_FIELD(unsigned long, pfn, pfn)
+	),
+	TPRAWFMT("mm %p address %lx pfn %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_anon_unmap,
+	TPPROTO(unsigned long pfn, int success),
+	TPARGS(pfn, success),
+	TPFMT("%s: pfn=%lx", pfn, success ? "succeeded" : "failed"),
+	TRACE_STRUCT(
+		TRACE_FIELD(unsigned long, pfn, pfn)
+		TRACE_FIELD(int, success, success)
+	),
+	TPRAWFMT("pfn %lx success %x")
+	);
+
+TRACE_EVENT_FORMAT(mm_filemap_fault,
+	TPPROTO(struct mm_struct *mm, unsigned long address,
+			unsigned long pfn, int flag),
+	TPARGS(mm, address, pfn, flag),
+	TPFMT("%s: mm=%lx address=%lx pfn=%lx",
+		flag ? "pagein" : "primary fault", mm, address, pfn),
+	TRACE_STRUCT(
+		TRACE_FIELD(struct mm_struct *, mm, mm)
+		TRACE_FIELD(unsigned long, address, address)
+		TRACE_FIELD(unsigned long, pfn, pfn)
+		TRACE_FIELD(int, flag, flag)
+	),
+	TPRAWFMT("mm %p address %lx pfn %lx flag %x")
+	);
+
+TRACE_EVENT_FORMAT(mm_filemap_cow,
+	TPPROTO(struct mm_struct *mm, unsigned long address, unsigned long pfn),
+	TPARGS(mm, address, pfn),
+	TPFMT("mm=%lx address=%lx pfn=%lx", mm, address, pfn),
+	TRACE_STRUCT(
+		TRACE_FIELD(struct mm_struct *, mm, mm)
+		TRACE_FIELD(unsigned long, address, address)
+		TRACE_FIELD(unsigned long, pfn, pfn)
+	),
+	TPRAWFMT("mm %p address %lx pfn %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_filemap_unmap,
+	TPPROTO(unsigned long pfn, int success),
+	TPARGS(pfn, success),
+	TPFMT("%s: pfn=%lx", pfn, success ? "succeeded" : "failed"),
+	TRACE_STRUCT(
+		TRACE_FIELD(unsigned long, pfn, pfn)
+		TRACE_FIELD(int, success, success)
+	),
+	TPRAWFMT("pfn %lx success %x")
+	);
+
+TRACE_EVENT_FORMAT(mm_filemap_userunmap,
+	TPPROTO(struct mm_struct *mm, unsigned long address, unsigned long pfn),
+	TPARGS(mm, address, pfn),
+	TPFMT("mm=%lx address=%lx pfn=%lx", mm, address, pfn),
+	TRACE_STRUCT(
+		TRACE_FIELD(struct mm_struct *, mm, mm)
+		TRACE_FIELD(unsigned long, address, address)
+		TRACE_FIELD(unsigned long, pfn, pfn)
+	),
+	TPRAWFMT("mm %p address %lx pfn %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_pagereclaim_pgout,
+	TPPROTO(unsigned long pfn, int anon),
+	TPARGS(pfn, anon),
+	TPFMT("%s page: pfn=%lx", pfn, anon ? "anonymous" : "pagecache"),
+	TRACE_STRUCT(
+		TRACE_FIELD(unsigned long, pfn, pfn)
+	),
+	TPRAWFMT("pfn %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_pagereclaim_free,
+	TPPROTO(unsigned long pfn, int anon),
+	TPARGS(pfn, anon),
+	TPFMT("%s page: pfn=%lx", pfn, anon ? "anonymous" : "pagecache"),
+	TRACE_STRUCT(
+		TRACE_FIELD(unsigned long, pfn, pfn)
+	),
+	TPRAWFMT("pfn %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_pdflush_bgwriteout,
+	TPPROTO(unsigned long count),
+	TPARGS(count),
+	TPFMT("count=%lx", count),
+	TRACE_STRUCT(
+		TRACE_FIELD(unsigned long, count, count)
+	),
+	TPRAWFMT("count %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_pdflush_kupdate,
+	TPPROTO(unsigned long count),
+	TPARGS(count),
+	TPFMT("count=%lx", count),
+	TRACE_STRUCT(
+		TRACE_FIELD(unsigned long, count, count)
+	),
+	TPRAWFMT("count %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_page_allocation,
+	TPPROTO(unsigned long pfn, unsigned long free),
+	TPARGS(pfn, free),
+	TPFMT("pfn=%lx zone_free=%ld", pfn, free),
+	TRACE_STRUCT(
+		TRACE_FIELD(unsigned long, pfn, pfn)
+		TRACE_FIELD(unsigned long, free, free)
+	),
+	TPRAWFMT("pfn %lx free %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_kswapd_runs,
+	TPPROTO(unsigned long count),
+	TPARGS(count),
+	TPFMT("count=%lx", count),
+	TRACE_STRUCT(
+		TRACE_FIELD(unsigned long, count, count)
+	),
+	TPRAWFMT("count %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_directreclaim_reclaimall,
+	TPPROTO(unsigned long priority),
+	TPARGS(priority),
+	TPFMT("priority=%lx", priority),
+	TRACE_STRUCT(
+		TRACE_FIELD(unsigned long, priority, priority)
+	),
+	TPRAWFMT("priority %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_directreclaim_reclaimzone,
+	TPPROTO(unsigned long reclaimed),
+	TPARGS(reclaimed),
+	TPFMT("reclaimed=%lx", reclaimed),
+	TRACE_STRUCT(
+		TRACE_FIELD(unsigned long, reclaimed, reclaimed)
+	),
+	TPRAWFMT("reclaimed %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_pagereclaim_shrinkzone,
+	TPPROTO(unsigned long count),
+	TPARGS(count),
+	TPFMT("count=%lx", count),
+	TRACE_STRUCT(
+		TRACE_FIELD(unsigned long, count, count)
+	),
+	TPRAWFMT("count %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_pagereclaim_shrinkactive,
+	TPPROTO(unsigned long count),
+	TPARGS(count),
+	TPFMT("count=%lx", count),
+	TRACE_STRUCT(
+		TRACE_FIELD(unsigned long, count, count)
+	),
+	TPRAWFMT("count %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_pagereclaim_shrinkactive_a2a,
+	TPPROTO(unsigned long pfn),
+	TPARGS(pfn),
+	TPFMT("pfn=%lx", pfn),
+	TRACE_STRUCT(
+		TRACE_FIELD(unsigned long, pfn, pfn)
+	),
+	TPRAWFMT("pfn %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_pagereclaim_shrinkactive_a2i,
+	TPPROTO(unsigned long pfn),
+	TPARGS(pfn),
+	TPFMT("pfn=%lx", pfn),
+	TRACE_STRUCT(
+		TRACE_FIELD(unsigned long, pfn, pfn)
+	),
+	TPRAWFMT("pfn %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_pagereclaim_shrinkinactive,
+	TPPROTO(unsigned long count),
+	TPARGS(count),
+	TPFMT("count=%lx", count),
+	TRACE_STRUCT(
+		TRACE_FIELD(unsigned long, count, count)
+	),
+	TPRAWFMT("count %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_pagereclaim_shrinkinactive_i2a,
+	TPPROTO(unsigned long pfn),
+	TPARGS(pfn),
+	TPFMT("pfn=%lx", pfn),
+	TRACE_STRUCT(
+		TRACE_FIELD(unsigned long, pfn, pfn)
+	),
+	TPRAWFMT("pfn %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_pagereclaim_shrinkinactive_i2i,
+	TPPROTO(unsigned long pfn),
+	TPARGS(pfn),
+	TPFMT("pfn=%lx", pfn),
+	TRACE_STRUCT(
+		TRACE_FIELD(unsigned long, pfn, pfn)
+	),
+	TPRAWFMT("pfn %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_page_free,
+	TPPROTO(unsigned long pfn),
+	TPARGS(pfn),
+	TPFMT("pfn=%lx", pfn),
+	TRACE_STRUCT(
+		TRACE_FIELD(unsigned long, pfn, pfn)
+	),
+	TPRAWFMT("pfn %lx")
+	);
+#undef TRACE_SYSTEM
+
+#undef TRACE_SYSTEM
--- linux-2.6-tip/include/trace/trace_events.h.orig	2009-03-16 12:05:59.000000000 -0400
+++ linux-2.6-tip/include/trace/trace_events.h	2009-03-16 12:10:49.000000000 -0400
@@ -3,3 +3,4 @@
 #include <trace/sched.h>
 #include <trace/irq.h>
 #include <trace/lockdep.h>
+#include <trace/mm.h>
--- linux-2.6-tip/include/trace/trace_event_types.h.orig	2009-03-16 12:05:59.000000000 -0400
+++ linux-2.6-tip/include/trace/trace_event_types.h	2009-03-16 12:10:49.000000000 -0400
@@ -3,3 +3,4 @@
 #include <trace/sched_event_types.h>
 #include <trace/irq_event_types.h>
 #include <trace/lockdep_event_types.h>
+#include <trace/mm_event_types.h>
--- /dev/null	2009-03-01 15:15:06.452930698 -0500
+++ linux-2.6-tip/include/trace/mm.h	2009-03-16 12:10:49.000000000 -0400
@@ -0,0 +1,9 @@
+#ifndef _TRACE_MM_H
+#define _TRACE_MM_H
+
+#include <linux/ktime.h>
+#include <linux/tracepoint.h>
+
+#include <trace/mm_event_types.h>
+
+#endif

Re: [Patch] mm tracepoints

[Rik van Riel]

Larry Woodman wrote:
> I've implemented several mm tracepoints to track page allocation and
> freeing, various types of pagefaults and unmaps, and critical page
> reclamation routines.  This is useful for debugging memory allocation
> issues and system performance problems under heavy memory loads.
> Thoughts?:

It looks mostly good.

I believe that the vmscan.c tracepoints could be a little
more verbose though, it would be useful to know whether we
are scanning anon or file pages and whether or not we're
doing lumpy reclaim.  Possibly the priority level, too.

-- 
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Re: [Patch] mm tracepoints

[Larry Woodman]

On Thu, 2009-03-19 at 11:47 -0400, Rik van Riel wrote:
> Larry Woodman wrote:
> > I've implemented several mm tracepoints to track page allocation and
> > freeing, various types of pagefaults and unmaps, and critical page
> > reclamation routines.  This is useful for debugging memory allocation
> > issues and system performance problems under heavy memory loads.
> > Thoughts?:
> 
> It looks mostly good.
> 
> I believe that the vmscan.c tracepoints could be a little
> more verbose though, it would be useful to know whether we
> are scanning anon or file pages and whether or not we're
> doing lumpy reclaim.  Possibly the priority level, too.
> 

OK thanks, I'll address these concerns.

Larry


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Re: [Patch] mm tracepoints

[Larry Woodman]

[-- Attachment #1: Type: text/plain, Size: 720 bytes --]

On Thu, 2009-03-19 at 11:47 -0400, Rik van Riel wrote:
> Larry Woodman wrote:
> > I've implemented several mm tracepoints to track page allocation and
> > freeing, various types of pagefaults and unmaps, and critical page
> > reclamation routines.  This is useful for debugging memory allocation
> > issues and system performance problems under heavy memory loads.
> > Thoughts?:
> 
> It looks mostly good.
> 
> I believe that the vmscan.c tracepoints could be a little
> more verbose though, it would be useful to know whether we
> are scanning anon or file pages and whether or not we're
> doing lumpy reclaim.  Possibly the priority level, too.
> 

The attached patch addresses your concerns.  Can you have a look:



[-- Attachment #2: upstream-mm_tracepoints.patch --]
[-- Type: text/x-patch, Size: 22755 bytes --]

diff --git a/include/trace/mm.h b/include/trace/mm.h
new file mode 100644
index 0000000..a3e760e
--- /dev/null
+++ b/include/trace/mm.h
@@ -0,0 +1,9 @@
+#ifndef _TRACE_MM_H
+#define _TRACE_MM_H
+
+#include <linux/ktime.h>
+#include <linux/tracepoint.h>
+
+#include <trace/mm_event_types.h>
+
+#endif
diff --git a/include/trace/mm_event_types.h b/include/trace/mm_event_types.h
new file mode 100644
index 0000000..0100d43
--- /dev/null
+++ b/include/trace/mm_event_types.h
@@ -0,0 +1,285 @@
+/* use <trace/mm.h> instead */
+#ifndef TRACE_FORMAT
+# error Do not include this file directly.
+# error Unless you know what you are doing.
+#endif
+
+#undef TRACE_SYSTEM
+#define TRACE_SYSTEM mm
+
+TRACE_EVENT_FORMAT(mm_anon_fault,
+	TPPROTO(struct mm_struct *mm, unsigned long address, unsigned long pfn),
+	TPARGS(mm, address, pfn),
+	TPFMT("mm=%lx address=%lx pfn=%lx", mm, address, pfn),
+	TRACE_STRUCT(
+		TRACE_FIELD(struct mm_struct *, mm, mm)
+		TRACE_FIELD(unsigned long, address, address)
+		TRACE_FIELD(unsigned long, pfn, pfn)
+	),
+	TPRAWFMT("mm %p address %lx pfn %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_anon_pgin,
+	TPPROTO(struct mm_struct *mm, unsigned long address, unsigned long pfn),
+	TPARGS(mm, address, pfn),
+	TPFMT("mm=%lx address=%lx pfn=%lx", mm, address, pfn),
+	TRACE_STRUCT(
+		TRACE_FIELD(struct mm_struct *, mm, mm)
+		TRACE_FIELD(unsigned long, address, address)
+		TRACE_FIELD(unsigned long, pfn, pfn)
+	),
+	TPRAWFMT("mm %p address %lx pfn %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_anon_cow,
+	TPPROTO(struct mm_struct *mm, unsigned long address, unsigned long pfn),
+	TPARGS(mm, address, pfn),
+	TPFMT("mm=%lx address=%lx pfn=%lx", mm, address, pfn),
+	TRACE_STRUCT(
+		TRACE_FIELD(struct mm_struct *, mm, mm)
+		TRACE_FIELD(unsigned long, address, address)
+		TRACE_FIELD(unsigned long, pfn, pfn)
+	),
+	TPRAWFMT("mm %p address %lx pfn %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_anon_userfree,
+	TPPROTO(struct mm_struct *mm, unsigned long address, unsigned long pfn),
+	TPARGS(mm, address, pfn),
+	TPFMT("mm=%lx address=%lx pfn=%lx", mm, address, pfn),
+	TRACE_STRUCT(
+		TRACE_FIELD(struct mm_struct *, mm, mm)
+		TRACE_FIELD(unsigned long, address, address)
+		TRACE_FIELD(unsigned long, pfn, pfn)
+	),
+	TPRAWFMT("mm %p address %lx pfn %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_anon_unmap,
+	TPPROTO(unsigned long pfn, int success),
+	TPARGS(pfn, success),
+	TPFMT("%s: pfn=%lx", success ? "succeeded" : "failed", pfn),
+	TRACE_STRUCT(
+		TRACE_FIELD(unsigned long, pfn, pfn)
+		TRACE_FIELD(int, success, success)
+	),
+	TPRAWFMT("pfn %lx success %x")
+	);
+
+TRACE_EVENT_FORMAT(mm_filemap_fault,
+	TPPROTO(struct mm_struct *mm, unsigned long address,
+			unsigned long pfn, int flag),
+	TPARGS(mm, address, pfn, flag),
+	TPFMT("%s: mm=%lx address=%lx pfn=%lx",
+		flag ? "pagein" : "primary fault", mm, address, pfn),
+	TRACE_STRUCT(
+		TRACE_FIELD(struct mm_struct *, mm, mm)
+		TRACE_FIELD(unsigned long, address, address)
+		TRACE_FIELD(unsigned long, pfn, pfn)
+		TRACE_FIELD(int, flag, flag)
+	),
+	TPRAWFMT("mm %p address %lx pfn %lx flag %x")
+	);
+
+TRACE_EVENT_FORMAT(mm_filemap_cow,
+	TPPROTO(struct mm_struct *mm, unsigned long address, unsigned long pfn),
+	TPARGS(mm, address, pfn),
+	TPFMT("mm=%lx address=%lx pfn=%lx", mm, address, pfn),
+	TRACE_STRUCT(
+		TRACE_FIELD(struct mm_struct *, mm, mm)
+		TRACE_FIELD(unsigned long, address, address)
+		TRACE_FIELD(unsigned long, pfn, pfn)
+	),
+	TPRAWFMT("mm %p address %lx pfn %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_filemap_unmap,
+	TPPROTO(unsigned long pfn, int success),
+	TPARGS(pfn, success),
+	TPFMT("%s: pfn=%lx", success ? "succeeded" : "failed", pfn),
+	TRACE_STRUCT(
+		TRACE_FIELD(unsigned long, pfn, pfn)
+		TRACE_FIELD(int, success, success)
+	),
+	TPRAWFMT("pfn %lx success %x")
+	);
+
+TRACE_EVENT_FORMAT(mm_filemap_userunmap,
+	TPPROTO(struct mm_struct *mm, unsigned long address, unsigned long pfn),
+	TPARGS(mm, address, pfn),
+	TPFMT("mm=%lx address=%lx pfn=%lx", mm, address, pfn),
+	TRACE_STRUCT(
+		TRACE_FIELD(struct mm_struct *, mm, mm)
+		TRACE_FIELD(unsigned long, address, address)
+		TRACE_FIELD(unsigned long, pfn, pfn)
+	),
+	TPRAWFMT("mm %p address %lx pfn %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_pagereclaim_pgout,
+	TPPROTO(unsigned long pfn, int anon),
+	TPARGS(pfn, anon),
+	TPFMT("%s page: pfn=%lx", anon ? "anonymous" : "pagecache", pfn),
+	TRACE_STRUCT(
+		TRACE_FIELD(unsigned long, pfn, pfn)
+	),
+	TPRAWFMT("pfn %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_pagereclaim_free,
+	TPPROTO(unsigned long pfn, int anon),
+	TPARGS(pfn, anon),
+	TPFMT("%s page: pfn=%lx", anon ? "anonymous" : "pagecache", pfn),
+	TRACE_STRUCT(
+		TRACE_FIELD(unsigned long, pfn, pfn)
+	),
+	TPRAWFMT("pfn %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_pdflush_bgwriteout,
+	TPPROTO(unsigned long count),
+	TPARGS(count),
+	TPFMT("count=%lx", count),
+	TRACE_STRUCT(
+		TRACE_FIELD(unsigned long, count, count)
+	),
+	TPRAWFMT("count %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_pdflush_kupdate,
+	TPPROTO(unsigned long count),
+	TPARGS(count),
+	TPFMT("count=%lx", count),
+	TRACE_STRUCT(
+		TRACE_FIELD(unsigned long, count, count)
+	),
+	TPRAWFMT("count %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_page_allocation,
+	TPPROTO(unsigned long pfn, unsigned long free),
+	TPARGS(pfn, free),
+	TPFMT("pfn=%lx zone_free=%ld", pfn, free),
+	TRACE_STRUCT(
+		TRACE_FIELD(unsigned long, pfn, pfn)
+		TRACE_FIELD(unsigned long, free, free)
+	),
+	TPRAWFMT("pfn %lx free %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_kswapd_runs,
+	TPPROTO(unsigned long reclaimed),
+	TPARGS(reclaimed),
+	TPFMT("reclaimed=%lx", reclaimed),
+	TRACE_STRUCT(
+		TRACE_FIELD(unsigned long, reclaimed, reclaimed)
+	),
+	TPRAWFMT("reclaimed %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_directreclaim_reclaimall,
+	TPPROTO(unsigned long priority),
+	TPARGS(priority),
+	TPFMT("priority=%lx", priority),
+	TRACE_STRUCT(
+		TRACE_FIELD(unsigned long, priority, priority)
+	),
+	TPRAWFMT("priority %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_directreclaim_reclaimzone,
+	TPPROTO(unsigned long reclaimed),
+	TPARGS(reclaimed),
+	TPFMT("reclaimed=%lx", reclaimed),
+	TRACE_STRUCT(
+		TRACE_FIELD(unsigned long, reclaimed, reclaimed)
+	),
+	TPRAWFMT("reclaimed %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_pagereclaim_shrinkzone,
+	TPPROTO(unsigned long reclaimed),
+	TPARGS(reclaimed),
+	TPFMT("reclaimed=%lx", reclaimed),
+	TRACE_STRUCT(
+		TRACE_FIELD(unsigned long, reclaimed, reclaimed)
+	),
+	TPRAWFMT("reclaimed %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_pagereclaim_shrinkactive,
+	TPPROTO(unsigned long scanned, int file, int priority),
+	TPARGS(scanned, file, priority),
+	TPFMT("scanned=%lx, %s, priority=%d", scanned, file ? "anonymous" : "pagecache", priority),
+	TRACE_STRUCT(
+		TRACE_FIELD(unsigned long, scanned, scanned)
+		TRACE_FIELD(int, file, file)
+		TRACE_FIELD(int, priority, priority)
+	),
+	TPRAWFMT("scanned %lx file %x priority %x")
+	);
+
+TRACE_EVENT_FORMAT(mm_pagereclaim_shrinkactive_a2a,
+	TPPROTO(unsigned long pfn),
+	TPARGS(pfn),
+	TPFMT("pfn=%lx", pfn),
+	TRACE_STRUCT(
+		TRACE_FIELD(unsigned long, pfn, pfn)
+	),
+	TPRAWFMT("pfn %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_pagereclaim_shrinkactive_a2i,
+	TPPROTO(unsigned long pfn),
+	TPARGS(pfn),
+	TPFMT("pfn=%lx", pfn),
+	TRACE_STRUCT(
+		TRACE_FIELD(unsigned long, pfn, pfn)
+	),
+	TPRAWFMT("pfn %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_pagereclaim_shrinkinactive,
+	TPPROTO(unsigned long reclaimed, int file, int priority),
+	TPARGS(reclaimed, file, priority),
+	TPFMT("reclaimed=%lx, %s, priority=%d", reclaimed, file ? "anonymous" : "pagecache", priority),
+	TRACE_STRUCT(
+		TRACE_FIELD(unsigned long, reclaimed, reclaimed)
+		TRACE_FIELD(int, file, file)
+		TRACE_FIELD(int, priority, priority)
+	),
+	TPRAWFMT("reclaimed %lx file %x priority %x")
+	);
+
+TRACE_EVENT_FORMAT(mm_pagereclaim_shrinkinactive_i2a,
+	TPPROTO(unsigned long pfn),
+	TPARGS(pfn),
+	TPFMT("pfn=%lx", pfn),
+	TRACE_STRUCT(
+		TRACE_FIELD(unsigned long, pfn, pfn)
+	),
+	TPRAWFMT("pfn %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_pagereclaim_shrinkinactive_i2i,
+	TPPROTO(unsigned long pfn),
+	TPARGS(pfn),
+	TPFMT("pfn=%lx", pfn),
+	TRACE_STRUCT(
+		TRACE_FIELD(unsigned long, pfn, pfn)
+	),
+	TPRAWFMT("pfn %lx")
+	);
+
+TRACE_EVENT_FORMAT(mm_page_free,
+	TPPROTO(unsigned long pfn),
+	TPARGS(pfn),
+	TPFMT("pfn=%lx", pfn),
+	TRACE_STRUCT(
+		TRACE_FIELD(unsigned long, pfn, pfn)
+	),
+	TPRAWFMT("pfn %lx")
+	);
+#undef TRACE_SYSTEM
+
+#undef TRACE_SYSTEM
diff --git a/include/trace/trace_event_types.h b/include/trace/trace_event_types.h
index df56f56..153d262 100644
--- a/include/trace/trace_event_types.h
+++ b/include/trace/trace_event_types.h
@@ -3,3 +3,4 @@
 #include <trace/sched_event_types.h>
 #include <trace/irq_event_types.h>
 #include <trace/lockdep_event_types.h>
+#include <trace/mm_event_types.h>
diff --git a/include/trace/trace_events.h b/include/trace/trace_events.h
index fd13750..2752e7f 100644
--- a/include/trace/trace_events.h
+++ b/include/trace/trace_events.h
@@ -3,3 +3,4 @@
 #include <trace/sched.h>
 #include <trace/irq.h>
 #include <trace/lockdep.h>
+#include <trace/mm.h>
diff --git a/mm/filemap.c b/mm/filemap.c
index 126d397..9c68755 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -34,6 +34,7 @@
 #include <linux/hardirq.h> /* for BUG_ON(!in_atomic()) only */
 #include <linux/memcontrol.h>
 #include <linux/mm_inline.h> /* for page_is_file_cache() */
+#include <trace/mm.h>
 #include "internal.h"
 
 /*
@@ -1436,6 +1437,7 @@ static int page_cache_read(struct file *file, pgoff_t offset)
 
 #define MMAP_LOTSAMISS  (100)
 
+DEFINE_TRACE(mm_filemap_fault);
 /**
  * filemap_fault - read in file data for page fault handling
  * @vma:	vma in which the fault was taken
@@ -1547,6 +1549,8 @@ retry_find:
 	 */
 	ra->prev_pos = (loff_t)page->index << PAGE_CACHE_SHIFT;
 	vmf->page = page;
+	trace_mm_filemap_fault(vma->vm_mm, (unsigned long)vmf->virtual_address,
+			page_to_pfn(page), vmf->flags&FAULT_FLAG_NONLINEAR);
 	return ret | VM_FAULT_LOCKED;
 
 no_cached_page:
diff --git a/mm/memory.c b/mm/memory.c
index baa999e..6acc389 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -55,6 +55,7 @@
 #include <linux/kallsyms.h>
 #include <linux/swapops.h>
 #include <linux/elf.h>
+#include <trace/mm.h>
 
 #include <asm/pgalloc.h>
 #include <asm/uaccess.h>
@@ -758,6 +759,8 @@ int copy_page_range(struct mm_struct *dst_mm, struct mm_struct *src_mm,
 	return ret;
 }
 
+DEFINE_TRACE(mm_anon_userfree);
+DEFINE_TRACE(mm_filemap_userunmap);
 static unsigned long zap_pte_range(struct mmu_gather *tlb,
 				struct vm_area_struct *vma, pmd_t *pmd,
 				unsigned long addr, unsigned long end,
@@ -812,15 +815,19 @@ static unsigned long zap_pte_range(struct mmu_gather *tlb,
 						addr) != page->index)
 				set_pte_at(mm, addr, pte,
 					   pgoff_to_pte(page->index));
-			if (PageAnon(page))
+			if (PageAnon(page)) {
 				anon_rss--;
-			else {
+				trace_mm_anon_userfree(mm, addr,
+							page_to_pfn(page));
+			} else {
 				if (pte_dirty(ptent))
 					set_page_dirty(page);
 				if (pte_young(ptent) &&
 				    likely(!VM_SequentialReadHint(vma)))
 					mark_page_accessed(page);
 				file_rss--;
+				trace_mm_filemap_userunmap(mm, addr,
+							page_to_pfn(page));
 			}
 			page_remove_rmap(page);
 			if (unlikely(page_mapcount(page) < 0))
@@ -1867,6 +1874,8 @@ static inline void cow_user_page(struct page *dst, struct page *src, unsigned lo
 		copy_user_highpage(dst, src, va, vma);
 }
 
+DEFINE_TRACE(mm_anon_cow);
+DEFINE_TRACE(mm_filemap_cow);
 /*
  * This routine handles present pages, when users try to write
  * to a shared page. It is done by copying the page to a new address
@@ -1889,7 +1898,7 @@ static int do_wp_page(struct mm_struct *mm, struct vm_area_struct *vma,
 		unsigned long address, pte_t *page_table, pmd_t *pmd,
 		spinlock_t *ptl, pte_t orig_pte)
 {
-	struct page *old_page, *new_page;
+	struct page *old_page, *new_page = NULL;
 	pte_t entry;
 	int reuse = 0, ret = 0;
 	int page_mkwrite = 0;
@@ -2019,9 +2028,14 @@ gotten:
 			if (!PageAnon(old_page)) {
 				dec_mm_counter(mm, file_rss);
 				inc_mm_counter(mm, anon_rss);
+				trace_mm_filemap_cow(mm, address,
+					page_to_pfn(new_page));
 			}
-		} else
+		} else {
 			inc_mm_counter(mm, anon_rss);
+			trace_mm_anon_cow(mm, address,
+					page_to_pfn(new_page));
+		}
 		flush_cache_page(vma, address, pte_pfn(orig_pte));
 		entry = mk_pte(new_page, vma->vm_page_prot);
 		entry = maybe_mkwrite(pte_mkdirty(entry), vma);
@@ -2386,6 +2400,7 @@ int vmtruncate_range(struct inode *inode, loff_t offset, loff_t end)
 	return 0;
 }
 
+DEFINE_TRACE(mm_anon_pgin);
 /*
  * We enter with non-exclusive mmap_sem (to exclude vma changes,
  * but allow concurrent faults), and pte mapped but not yet locked.
@@ -2499,6 +2514,7 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma,
 unlock:
 	pte_unmap_unlock(page_table, ptl);
 out:
+	trace_mm_anon_pgin(mm, address, page_to_pfn(page));
 	return ret;
 out_nomap:
 	mem_cgroup_cancel_charge_swapin(ptr);
@@ -2508,6 +2524,7 @@ out_nomap:
 	return ret;
 }
 
+DEFINE_TRACE(mm_anon_fault);
 /*
  * We enter with non-exclusive mmap_sem (to exclude vma changes,
  * but allow concurrent faults), and pte mapped but not yet locked.
@@ -2531,6 +2548,7 @@ static int do_anonymous_page(struct mm_struct *mm, struct vm_area_struct *vma,
 		goto oom;
 	__SetPageUptodate(page);
 
+	trace_mm_anon_fault(mm, address, page_to_pfn(page));
 	if (mem_cgroup_newpage_charge(page, mm, GFP_KERNEL))
 		goto oom_free_page;
 
diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 74dc57c..7ebd33c 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -34,6 +34,7 @@
 #include <linux/syscalls.h>
 #include <linux/buffer_head.h>
 #include <linux/pagevec.h>
+#include <trace/mm.h>
 
 /*
  * The maximum number of pages to writeout in a single bdflush/kupdate
@@ -677,6 +678,7 @@ void throttle_vm_writeout(gfp_t gfp_mask)
         }
 }
 
+DEFINE_TRACE(mm_pdflush_bgwriteout);
 /*
  * writeback at least _min_pages, and keep writing until the amount of dirty
  * memory is less than the background threshold, or until we're all clean.
@@ -716,6 +718,7 @@ static void background_writeout(unsigned long _min_pages)
 				break;
 		}
 	}
+	trace_mm_pdflush_bgwriteout(_min_pages);
 }
 
 /*
@@ -737,6 +740,7 @@ static void laptop_timer_fn(unsigned long unused);
 static DEFINE_TIMER(wb_timer, wb_timer_fn, 0, 0);
 static DEFINE_TIMER(laptop_mode_wb_timer, laptop_timer_fn, 0, 0);
 
+DEFINE_TRACE(mm_pdflush_kupdate);
 /*
  * Periodic writeback of "old" data.
  *
@@ -776,6 +780,7 @@ static void wb_kupdate(unsigned long arg)
 	nr_to_write = global_page_state(NR_FILE_DIRTY) +
 			global_page_state(NR_UNSTABLE_NFS) +
 			(inodes_stat.nr_inodes - inodes_stat.nr_unused);
+	trace_mm_pdflush_kupdate(nr_to_write);
 	while (nr_to_write > 0) {
 		wbc.more_io = 0;
 		wbc.encountered_congestion = 0;
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 0d0633f..b088370 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -47,6 +47,7 @@
 #include <linux/page-isolation.h>
 #include <linux/page_cgroup.h>
 #include <linux/debugobjects.h>
+#include <trace/mm.h>
 
 #include <asm/tlbflush.h>
 #include <asm/div64.h>
@@ -994,6 +995,7 @@ void mark_free_pages(struct zone *zone)
 }
 #endif /* CONFIG_PM */
 
+DEFINE_TRACE(mm_page_free);
 /*
  * Free a 0-order page
  */
@@ -1010,6 +1012,7 @@ static void free_hot_cold_page(struct page *page, int cold)
 	if (free_pages_check(page))
 		return;
 
+	trace_mm_page_free(page_to_pfn(page));
 	if (!PageHighMem(page)) {
 		debug_check_no_locks_freed(page_address(page), PAGE_SIZE);
 		debug_check_no_obj_freed(page_address(page), PAGE_SIZE);
@@ -1399,6 +1402,7 @@ static void zlc_mark_zone_full(struct zonelist *zonelist, struct zoneref *z)
 }
 #endif	/* CONFIG_NUMA */
 
+DEFINE_TRACE(mm_page_allocation);
 /*
  * get_page_from_freelist goes through the zonelist trying to allocate
  * a page.
@@ -1453,8 +1457,11 @@ zonelist_scan:
 		}
 
 		page = buffered_rmqueue(preferred_zone, zone, order, gfp_mask);
-		if (page)
+		if (page) {
+			trace_mm_page_allocation(page_to_pfn(page),
+					zone_page_state(zone, NR_FREE_PAGES));
 			break;
+		}
 this_zone_full:
 		if (NUMA_BUILD)
 			zlc_mark_zone_full(zonelist, z);
diff --git a/mm/rmap.c b/mm/rmap.c
index 1652166..39a4876 100644
--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -50,6 +50,7 @@
 #include <linux/memcontrol.h>
 #include <linux/mmu_notifier.h>
 #include <linux/migrate.h>
+#include <trace/mm.h>
 
 #include <asm/tlbflush.h>
 
@@ -978,6 +979,7 @@ static int try_to_mlock_page(struct page *page, struct vm_area_struct *vma)
 	return mlocked;
 }
 
+DEFINE_TRACE(mm_anon_unmap);
 /**
  * try_to_unmap_anon - unmap or unlock anonymous page using the object-based
  * rmap method
@@ -1034,9 +1036,11 @@ static int try_to_unmap_anon(struct page *page, int unlock, int migration)
 	else if (ret == SWAP_MLOCK)
 		ret = SWAP_AGAIN;	/* saw VM_LOCKED vma */
 
+	trace_mm_anon_unmap(page_to_pfn(page), ret == SWAP_SUCCESS);
 	return ret;
 }
 
+DEFINE_TRACE(mm_filemap_unmap);
 /**
  * try_to_unmap_file - unmap/unlock file page using the object-based rmap method
  * @page: the page to unmap/unlock
@@ -1170,6 +1174,7 @@ out:
 		ret = SWAP_MLOCK;	/* actually mlocked the page */
 	else if (ret == SWAP_MLOCK)
 		ret = SWAP_AGAIN;	/* saw VM_LOCKED vma */
+	trace_mm_filemap_unmap(page_to_pfn(page), ret == SWAP_SUCCESS);
 	return ret;
 }
 
diff --git a/mm/vmscan.c b/mm/vmscan.c
index ae6f4c1..626b91f 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -40,6 +40,7 @@
 #include <linux/memcontrol.h>
 #include <linux/delayacct.h>
 #include <linux/sysctl.h>
+#include <trace/mm.h>
 
 #include <asm/tlbflush.h>
 #include <asm/div64.h>
@@ -329,6 +330,7 @@ typedef enum {
 	PAGE_CLEAN,
 } pageout_t;
 
+DEFINE_TRACE(mm_pagereclaim_pgout);
 /*
  * pageout is called by shrink_page_list() for each dirty page.
  * Calls ->writepage().
@@ -407,6 +409,7 @@ static pageout_t pageout(struct page *page, struct address_space *mapping,
 			ClearPageReclaim(page);
 		}
 		inc_zone_page_state(page, NR_VMSCAN_WRITE);
+		trace_mm_pagereclaim_pgout(page_to_pfn(page), PageAnon(page));
 		return PAGE_SUCCESS;
 	}
 
@@ -570,6 +573,9 @@ void putback_lru_page(struct page *page)
 #endif /* CONFIG_UNEVICTABLE_LRU */
 
 
+DEFINE_TRACE(mm_pagereclaim_free);
+DEFINE_TRACE(mm_pagereclaim_shrinkinactive_i2a);
+DEFINE_TRACE(mm_pagereclaim_shrinkinactive_i2i);
 /*
  * shrink_page_list() returns the number of reclaimed pages
  */
@@ -758,6 +764,7 @@ free_it:
 			__pagevec_free(&freed_pvec);
 			pagevec_reinit(&freed_pvec);
 		}
+		trace_mm_pagereclaim_free(page_to_pfn(page), PageAnon(page));
 		continue;
 
 cull_mlocked:
@@ -774,10 +781,12 @@ activate_locked:
 		VM_BUG_ON(PageActive(page));
 		SetPageActive(page);
 		pgactivate++;
+		trace_mm_pagereclaim_shrinkinactive_i2a(page_to_pfn(page));
 keep_locked:
 		unlock_page(page);
 keep:
 		list_add(&page->lru, &ret_pages);
+		trace_mm_pagereclaim_shrinkinactive_i2i(page_to_pfn(page));
 		VM_BUG_ON(PageLRU(page) || PageUnevictable(page));
 	}
 	list_splice(&ret_pages, page_list);
@@ -1036,6 +1045,7 @@ int isolate_lru_page(struct page *page)
 	return ret;
 }
 
+DEFINE_TRACE(mm_pagereclaim_shrinkinactive);
 /*
  * shrink_inactive_list() is a helper for shrink_zone().  It returns the number
  * of reclaimed pages
@@ -1170,6 +1180,7 @@ static unsigned long shrink_inactive_list(unsigned long max_scan,
 done:
 	local_irq_enable();
 	pagevec_release(&pvec);
+	trace_mm_pagereclaim_shrinkinactive(nr_reclaimed, file, priority);
 	return nr_reclaimed;
 }
 
@@ -1187,6 +1198,9 @@ static inline void note_zone_scanning_priority(struct zone *zone, int priority)
 		zone->prev_priority = priority;
 }
 
+DEFINE_TRACE(mm_pagereclaim_shrinkactive);
+DEFINE_TRACE(mm_pagereclaim_shrinkactive_a2a);
+DEFINE_TRACE(mm_pagereclaim_shrinkactive_a2i);
 /*
  * This moves pages from the active list to the inactive list.
  *
@@ -1247,6 +1261,7 @@ static void shrink_active_list(unsigned long nr_pages, struct zone *zone,
 
 		if (unlikely(!page_evictable(page, NULL))) {
 			putback_lru_page(page);
+			trace_mm_pagereclaim_shrinkactive_a2a(page_to_pfn(page));
 			continue;
 		}
 
@@ -1256,6 +1271,7 @@ static void shrink_active_list(unsigned long nr_pages, struct zone *zone,
 			pgmoved++;
 
 		list_add(&page->lru, &l_inactive);
+		trace_mm_pagereclaim_shrinkactive_a2i(page_to_pfn(page));
 	}
 
 	/*
@@ -1310,6 +1326,7 @@ static void shrink_active_list(unsigned long nr_pages, struct zone *zone,
 		pagevec_swap_free(&pvec);
 
 	pagevec_release(&pvec);
+	trace_mm_pagereclaim_shrinkactive(pgscanned, file, priority);
 }
 
 static int inactive_anon_is_low_global(struct zone *zone)
@@ -1450,6 +1467,7 @@ static void get_scan_ratio(struct zone *zone, struct scan_control *sc,
 }
 
 
+DEFINE_TRACE(mm_pagereclaim_shrinkzone);
 /*
  * This is a basic per-zone page freer.  Used by both kswapd and direct reclaim.
  */
@@ -1510,6 +1528,7 @@ static void shrink_zone(int priority, struct zone *zone,
 	}
 
 	sc->nr_reclaimed = nr_reclaimed;
+	trace_mm_pagereclaim_shrinkzone(nr_reclaimed);
 
 	/*
 	 * Even if we did not try to evict anon pages at all, we want to
@@ -1521,6 +1540,7 @@ static void shrink_zone(int priority, struct zone *zone,
 	throttle_vm_writeout(sc->gfp_mask);
 }
 
+DEFINE_TRACE(mm_directreclaim_reclaimall);
 /*
  * This is the direct reclaim path, for page-allocating processes.  We only
  * try to reclaim pages from zones which will satisfy the caller's allocation
@@ -1569,6 +1589,7 @@ static void shrink_zones(int priority, struct zonelist *zonelist,
 							priority);
 		}
 
+		trace_mm_directreclaim_reclaimall(priority);
 		shrink_zone(priority, zone, sc);
 	}
 }
@@ -1732,6 +1753,7 @@ unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *mem_cont,
 }
 #endif
 
+DEFINE_TRACE(mm_kswapd_runs);
 /*
  * For kswapd, balance_pgdat() will work across all this node's zones until
  * they are all at pages_high.
@@ -1938,6 +1960,7 @@ out:
 		goto loop_again;
 	}
 
+	trace_mm_kswapd_runs(sc.nr_reclaimed);
 	return sc.nr_reclaimed;
 }
 
@@ -2278,6 +2301,7 @@ int sysctl_min_unmapped_ratio = 1;
  */
 int sysctl_min_slab_ratio = 5;
 
+DEFINE_TRACE(mm_directreclaim_reclaimzone);
 /*
  * Try to free up some pages from this zone through reclaim.
  */
@@ -2321,6 +2345,7 @@ static int __zone_reclaim(struct zone *zone, gfp_t gfp_mask, unsigned int order)
 		do {
 			note_zone_scanning_priority(zone, priority);
 			shrink_zone(priority, zone, &sc);
+			trace_mm_directreclaim_reclaimzone(priority);
 			priority--;
 		} while (priority >= 0 && sc.nr_reclaimed < nr_pages);
 	}
@@ -2352,6 +2377,7 @@ static int __zone_reclaim(struct zone *zone, gfp_t gfp_mask, unsigned int order)
 
 	p->reclaim_state = NULL;
 	current->flags &= ~(PF_MEMALLOC | PF_SWAPWRITE);
+	trace_mm_directreclaim_reclaimzone(sc.nr_reclaimed);
 	return sc.nr_reclaimed >= nr_pages;
 }
 

Re: marching through all physical memory in software

[Eric W. Biederman]

"Chris Friesen" <cfriesen@nortel.com> writes:

> Arjan van de Ven wrote:
>> On Mon, 26 Jan 2009 09:38:13 -0600
>> "Chris Friesen" <cfriesen@nortel.com> wrote:
>>
>>> Someone is asking me about the feasability of "scrubbing" system
>>> memory by accessing each page and handling the ECC faults.
>>>
>>
>> Hi,
>>
>> I would suggest that you look at the "edac" subsystem, which tries to
>> do exactly this....


> edac appears to currently be able to scrub the specific page where the fault
> occurred.  This is a useful building block, but doesn't provide the ability to
> march through all of physical memory.

Well that is the tricky part.  The rest is simply finding which physical
addresses are valid.  Either by querying the memory controller or looking
at the range the BIOS gave us.

That part should not be too hard.  I think it simply has not been implemented
yet as most ECC chipsets implement this in hardware today.

Eric

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Re: marching through all physical memory in software

[Pavel Machek]

On Tue 2009-01-27 12:16:52, Eric W. Biederman wrote:
> "Chris Friesen" <cfriesen@nortel.com> writes:
> 
> > Arjan van de Ven wrote:
> >> On Mon, 26 Jan 2009 09:38:13 -0600
> >> "Chris Friesen" <cfriesen@nortel.com> wrote:
> >>
> >>> Someone is asking me about the feasability of "scrubbing" system
> >>> memory by accessing each page and handling the ECC faults.
> >>>
> >>
> >> Hi,
> >>
> >> I would suggest that you look at the "edac" subsystem, which tries to
> >> do exactly this....
> 
> 
> > edac appears to currently be able to scrub the specific page where the fault
> > occurred.  This is a useful building block, but doesn't provide the ability to
> > march through all of physical memory.
> 
> Well that is the tricky part.  The rest is simply finding which physical
> addresses are valid.  Either by querying the memory controller or looking
> at the range the BIOS gave us.
> 
> That part should not be too hard.  I think it simply has not been implemented
> yet as most ECC chipsets implement this in hardware today.

You can do the scrubbing today by echo reboot > /sys/power/disk; echo
disk > /sys/power/state :-)... or using uswsusp APIs.

Take a look at hibernation code for 'walk all memory' examples...  

-- 
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(cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html

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Re: marching through all physical memory in software

[Nigel Cunningham]

Hi.

On Wed, 2009-01-28 at 20:38 +0100, Pavel Machek wrote:
> You can do the scrubbing today by echo reboot > /sys/power/disk; echo
> disk > /sys/power/state :-)... or using uswsusp APIs.

That won't work. The RAM retains it's contents across a reboot, and even
for a little while after powering off.

Regards,

Nigel

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Re: [Patch] mm tracepoints

[Andrew Morton]

On Thu, 05 Mar 2009 17:16:40 -0500
Larry Woodman <lwoodman@redhat.com> wrote:

> I've implemented several mm tracepoints to track page allocation and
> freeing, various types of pagefaults and unmaps, and critical page
> reclamation routines.  This is useful for debugging memory allocation
> issues and system performance problems under heavy memory loads:
> 
> # tracer: mm
> #
> #           TASK-PID    CPU#    TIMESTAMP  FUNCTION
> #              | |       |          |         |
>          pdflush-624   [004]   184.293169: wb_kupdate:
> (mm_pdflush_kupdate) count=3e48
>          pdflush-624   [004]   184.293439: get_page_from_freelist:
> (mm_page_allocation) pfn=447c27 zone_free=1940910
>         events/6-33    [006]   184.962879: free_hot_cold_page:
> (mm_page_free) pfn=44bba9
>       irqbalance-8313  [001]   188.042951: unmap_vmas:
> (mm_anon_userfree) mm=ffff88044a7300c0 address=7f9a2eb70000 pfn=24c29a
>              cat-9122  [005]   191.141173: filemap_fault:
> (mm_filemap_fault) primary fault: mm=ffff88024c9d8f40 address=3cea2dd000
> pfn=44d68e
>              cat-9122  [001]   191.143036: handle_mm_fault:
> (mm_anon_fault) mm=ffff88024c8beb40 address=7fffbde99f94 pfn=24ce22
> ...

I'm struggling to think of any memory management problems which this
facility would have helped us solve.  Single-page tracing like this
isn't very interesting or useful.

What we generally are looking for when resolving MM
performance/correctness problems is a representation/visualisation of
aggregated results over a period of time.  That means synchronous or
downstream processing of large amounts of bulk data.

Now, possibly the above information could be used to generate the
needed information.  But the above rather random-looking and chaotic
data output would make it very hard to develop the needed
aggregation/representation tools.

And unless someone actually develops those tools (which is a lot of
work), there isn't much point in adding the kernel infrastructure to
generate the data for the non-existing tool.

I haven't looked at LTT in a while.  What sort of information does it
extract from the MM system?  Is it useful to MM developers?  If so, can
this newly-proposed facility do the same thing?


How about a test case - how could this patch help us (and our testers)
make some progress with the infamous
http://bugzilla.kernel.org/show_bug.cgi?id=12309 ?


Then again, maybe I'm wrong!  Maybe MM developers _do_ believe that
this tool would assist them in their work.  Given that MM develoeprs
are the target market for this feature, it would be sensible to cc the
linux-mm list, methinks?

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