perf kmem: Add --live option for current allocation stat

Currently 'perf kmem stat --page' shows total (page) allocation stat by
default, but sometimes one might want to see live (total alloc-only)
requests/pages only.  The new --live option does this by subtracting freed
allocation from the stat.

E.g.:

 # perf kmem stat --page

 SUMMARY (page allocator)
 ========================
 Total allocation requests     :          988,858   [        4,045,368 KB ]
 Total free requests           :          886,484   [        3,624,996 KB ]

 Total alloc+freed requests    :          885,969   [        3,622,628 KB ]
 Total alloc-only requests     :          102,889   [          422,740 KB ]
 Total free-only requests      :              515   [            2,368 KB ]

 Total allocation failures     :                0   [                0 KB ]

 Order     Unmovable   Reclaimable       Movable      Reserved  CMA/Isolated
 -----  ------------  ------------  ------------  ------------  ------------
     0       172,173         3,083       806,686             .             .
     1           284             .             .             .             .
     2         6,124            58             .             .             .
     3           114           335             .             .             .
     4             .             .             .             .             .
     5             .             .             .             .             .
     6             .             .             .             .             .
     7             .             .             .             .             .
     8             .             .             .             .             .
     9             .             .             1             .             .
    10             .             .             .             .             .
 # perf kmem stat --page --live

 SUMMARY (page allocator)
 ========================
 Total allocation requests     :          988,858   [        4,045,368 KB ]
 Total free requests           :          886,484   [        3,624,996 KB ]

 Total alloc+freed requests    :          885,969   [        3,622,628 KB ]
 Total alloc-only requests     :          102,889   [          422,740 KB ]
 Total free-only requests      :              515   [            2,368 KB ]

 Total allocation failures     :                0   [                0 KB ]

 Order     Unmovable   Reclaimable       Movable      Reserved  CMA/Isolated
 -----  ------------  ------------  ------------  ------------  ------------
     0         2,214         3,025        97,156             .             .
     1            59             .             .             .             .
     2            19            58             .             .             .
     3            23           335             .             .             .
     4             .             .             .             .             .
     5             .             .             .             .             .
     6             .             .             .             .             .
     7             .             .             .             .             .
     8             .             .             .             .             .
     9             .             .             .             .             .
    10             .             .             .             .             .
 #

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Acked-by: Pekka Enberg <penberg@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Joonsoo Kim <js1304@gmail.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: linux-mm@kvack.org
Link: http://lkml.kernel.org/r/1429592107-1807-4-git-send-email-namhyung@kernel.org
[ Added examples to the changeset log ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 68 insertions, 42 deletions

diff --git a/tools/perf/builtin-kmem.c b/tools/perf/builtin-kmem.c
index 0393a7f3fa35..7ead9423fd7a 100644
--- a/tools/perf/builtin-kmem.c
+++ b/tools/perf/builtin-kmem.c
@@ -244,6 +244,7 @@ static unsigned long nr_page_fails;
 static unsigned long nr_page_nomatch;
 
 static bool use_pfn;
+static bool live_page;
 static struct perf_session *kmem_session;
 
 #define MAX_MIGRATE_TYPES  6
@@ -264,7 +265,7 @@ struct page_stat {
         int             nr_free;
 };
 
-static struct rb_root page_tree;
+static struct rb_root page_live_tree;
 static struct rb_root page_alloc_tree;
 static struct rb_root page_alloc_sorted;
 static struct rb_root page_caller_tree;
@@ -403,10 +404,19 @@ out:
         return sample->ip;
 }
 
+struct sort_dimension {
+        const char              name[20];
+        sort_fn_t               cmp;
+        struct list_head        list;
+};
+
+static LIST_HEAD(page_alloc_sort_input);
+static LIST_HEAD(page_caller_sort_input);
+
 static struct page_stat *
-__page_stat__findnew_page(u64 page, bool create)
+__page_stat__findnew_page(struct page_stat *pstat, bool create)
 {
-        struct rb_node **node = &page_tree.rb_node;
+        struct rb_node **node = &page_live_tree.rb_node;
         struct rb_node *parent = NULL;
         struct page_stat *data;
 
@@ -416,7 +426,7 @@ __page_stat__findnew_page(u64 page, bool create)
                 parent = *node;
                 data = rb_entry(*node, struct page_stat, node);
 
-                cmp = data->page - page;
+                cmp = data->page - pstat->page;
                 if (cmp < 0)
                         node = &parent->rb_left;
                 else if (cmp > 0)
@@ -430,34 +440,28 @@ __page_stat__findnew_page(u64 page, bool create)
 
         data = zalloc(sizeof(*data));
         if (data != NULL) {
-                data->page = page;
+                data->page = pstat->page;
+                data->order = pstat->order;
+                data->gfp_flags = pstat->gfp_flags;
+                data->migrate_type = pstat->migrate_type;
 
                 rb_link_node(&data->node, parent, node);
-                rb_insert_color(&data->node, &page_tree);
+                rb_insert_color(&data->node, &page_live_tree);
         }
 
         return data;
 }
 
-static struct page_stat *page_stat__find_page(u64 page)
+static struct page_stat *page_stat__find_page(struct page_stat *pstat)
 {
-        return __page_stat__findnew_page(page, false);
+        return __page_stat__findnew_page(pstat, false);
 }
 
-static struct page_stat *page_stat__findnew_page(u64 page)
+static struct page_stat *page_stat__findnew_page(struct page_stat *pstat)
 {
-        return __page_stat__findnew_page(page, true);
+        return __page_stat__findnew_page(pstat, true);
 }
 
-struct sort_dimension {
-        const char              name[20];
-        sort_fn_t               cmp;
-        struct list_head        list;
-};
-
-static LIST_HEAD(page_alloc_sort_input);
-static LIST_HEAD(page_caller_sort_input);
-
 static struct page_stat *
 __page_stat__findnew_alloc(struct page_stat *pstat, bool create)
 {
@@ -615,17 +619,8 @@ static int perf_evsel__process_page_alloc_event(struct perf_evsel *evsel,
          * This is to find the current page (with correct gfp flags and
          * migrate type) at free event.
          */
-        pstat = page_stat__findnew_page(page);
-        if (pstat == NULL)
-                return -ENOMEM;
-
-        pstat->order = order;
-        pstat->gfp_flags = gfp_flags;
-        pstat->migrate_type = migrate_type;
-        pstat->callsite = callsite;
-
         this.page = page;
-        pstat = page_stat__findnew_alloc(&this);
+        pstat = page_stat__findnew_page(&this);
         if (pstat == NULL)
                 return -ENOMEM;
 
@@ -633,6 +628,16 @@ static int perf_evsel__process_page_alloc_event(struct perf_evsel *evsel,
         pstat->alloc_bytes += bytes;
         pstat->callsite = callsite;
 
+        if (!live_page) {
+                pstat = page_stat__findnew_alloc(&this);
+                if (pstat == NULL)
+                        return -ENOMEM;
+
+                pstat->nr_alloc++;
+                pstat->alloc_bytes += bytes;
+                pstat->callsite = callsite;
+        }
+
         this.callsite = callsite;
         pstat = page_stat__findnew_caller(&this);
         if (pstat == NULL)
@@ -665,7 +670,8 @@ static int perf_evsel__process_page_free_event(struct perf_evsel *evsel,
         nr_page_frees++;
         total_page_free_bytes += bytes;
 
-        pstat = page_stat__find_page(page);
+        this.page = page;
+        pstat = page_stat__find_page(&this);
         if (pstat == NULL) {
                 pr_debug2("missing free at page %"PRIx64" (order: %d)\n",
                           page, order);
@@ -676,20 +682,23 @@ static int perf_evsel__process_page_free_event(struct perf_evsel *evsel,
                 return 0;
         }
 
-        this.page = page;
         this.gfp_flags = pstat->gfp_flags;
         this.migrate_type = pstat->migrate_type;
         this.callsite = pstat->callsite;
 
-        rb_erase(&pstat->node, &page_tree);
+        rb_erase(&pstat->node, &page_live_tree);
         free(pstat);
 
-        pstat = page_stat__find_alloc(&this);
-        if (pstat == NULL)
-                return -ENOENT;
+        if (live_page) {
+                order_stats[this.order][this.migrate_type]--;
+        } else {
+                pstat = page_stat__find_alloc(&this);
+                if (pstat == NULL)
+                        return -ENOMEM;
 
-        pstat->nr_free++;
-        pstat->free_bytes += bytes;
+                pstat->nr_free++;
+                pstat->free_bytes += bytes;
+        }
 
         pstat = page_stat__find_caller(&this);
         if (pstat == NULL)
@@ -698,6 +707,16 @@ static int perf_evsel__process_page_free_event(struct perf_evsel *evsel,
         pstat->nr_free++;
         pstat->free_bytes += bytes;
 
+        if (live_page) {
+                pstat->nr_alloc--;
+                pstat->alloc_bytes -= bytes;
+
+                if (pstat->nr_alloc == 0) {
+                        rb_erase(&pstat->node, &page_caller_tree);
+                        free(pstat);
+                }
+        }
+
         return 0;
 }
 
@@ -815,8 +834,8 @@ static void __print_page_alloc_result(struct perf_session *session, int n_lines)
         const char *format;
 
         printf("\n%.105s\n", graph_dotted_line);
-        printf(" %-16s | Total alloc (KB) | Hits      | Order | Mig.type | GFP flags | Callsite\n",
-               use_pfn ? "PFN" : "Page");
+        printf(" %-16s | %5s alloc (KB) | Hits      | Order | Mig.type | GFP flags | Callsite\n",
+               use_pfn ? "PFN" : "Page", live_page ? "Live" : "Total");
         printf("%.105s\n", graph_dotted_line);
 
         if (use_pfn)
@@ -860,7 +879,8 @@ static void __print_page_caller_result(struct perf_session *session, int n_lines
         struct machine *machine = &session->machines.host;
 
         printf("\n%.105s\n", graph_dotted_line);
-        printf(" Total alloc (KB) | Hits      | Order | Mig.type | GFP flags | Callsite\n");
+        printf(" %5s alloc (KB) | Hits      | Order | Mig.type | GFP flags | Callsite\n",
+               live_page ? "Live" : "Total");
         printf("%.105s\n", graph_dotted_line);
 
         while (next && n_lines--) {
@@ -1085,8 +1105,13 @@ static void sort_result(void)
                                    &slab_caller_sort);
         }
         if (kmem_page) {
-                __sort_page_result(&page_alloc_tree, &page_alloc_sorted,
-                                   &page_alloc_sort);
+                if (live_page)
+                        __sort_page_result(&page_live_tree, &page_alloc_sorted,
+                                           &page_alloc_sort);
+                else
+                        __sort_page_result(&page_alloc_tree, &page_alloc_sorted,
+                                           &page_alloc_sort);
+
                 __sort_page_result(&page_caller_tree, &page_caller_sorted,
                                    &page_caller_sort);
         }
@@ -1630,6 +1655,7 @@ int cmd_kmem(int argc, const char **argv, const char *prefix __maybe_unused)
                            parse_slab_opt),
         OPT_CALLBACK_NOOPT(0, "page", NULL, NULL, "Analyze page allocator",
                            parse_page_opt),
+        OPT_BOOLEAN(0, "live", &live_page, "Show live page stat"),
         OPT_END()
         };
         const char *const kmem_subcommands[] = { "record", "stat", NULL };