[PATCH 3/5] perf kmem: Collect cross node allocation statistics

Li Zefan
2009-11-24T05:27:06Z

Show cross node memory allocations:

# ./perf kmem

SUMMARY
=======
...
Cross node allocations: 0/3633

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
---
tools/perf/builtin-kmem.c | 81 +++++++++++++++++++++++++++++++++++++++++++-
1 files changed, 79 insertions(+), 2 deletions(-)

diff --git a/tools/perf/builtin-kmem.c b/tools/perf/builtin-kmem.c
index dc86f1e..1ecf3f4 100644
--- a/tools/perf/builtin-kmem.c
+++ b/tools/perf/builtin-kmem.c
@@ -36,6 +36,9 @@ static char default_sort_order[] = "frag,hit,bytes";
static char *cwd;
static int cwdlen;

+static int *cpunode_map;
+static int max_cpu_num;
+
struct alloc_stat {
union {
u64 call_site;
@@ -54,12 +57,74 @@ static struct rb_root root_caller_stat;
static struct rb_root root_caller_sorted;

static unsigned long total_requested, total_allocated;
+static unsigned long nr_allocs, nr_cross_allocs;

struct raw_event_sample {
u32 size;
char data[0];
};

+#define PATH_SYS_NODE "/sys/devices/system/node"
+
+static void init_cpunode_map(void)
+{
+ FILE *fp;
+ int i;
+
+ fp = fopen("/sys/devices/system/cpu/kernel_max", "r");
+ if (!fp) {
+ max_cpu_num = 4096;
+ return;
+ }
+
+ if (fscanf(fp, "%d", &max_cpu_num) < 1)
+ die("Failed to read 'kernel_max' from sysfs");
+ max_cpu_num++;
+
+ cpunode_map = calloc(max_cpu_num, sizeof(int));
+ if (!cpunode_map)
+ die("calloc");
+ for (i = 0; i < max_cpu_num; i++)
+ cpunode_map[i] = -1;
+ fclose(fp);
+}
+
+static void setup_cpunode_map(void)
+{
+ struct dirent *dent1, *dent2;
+ DIR *dir1, *dir2;
+ unsigned int cpu, mem;
+ char buf[PATH_MAX];
+
+ init_cpunode_map();
+
+ dir1 = opendir(PATH_SYS_NODE);
+ if (!dir1)
+ return;
+
+ while (true) {
+ dent1 = readdir(dir1);
+ if (!dent1)
+ break;
+
+ if (sscanf(dent1->d_name, "node%u", &mem) < 1)
+ continue;
+
+ snprintf(buf, PATH_MAX, "%s/%s", PATH_SYS_NODE, dent1->d_name);
+ dir2 = opendir(buf);
+ if (!dir2)
+ continue;
+ while (true) {
+ dent2 = readdir(dir2);
+ if (!dent2)
+ break;
+ if (sscanf(dent2->d_name, "cpu%u", &cpu) < 1)
+ continue;
+ cpunode_map[cpu] = mem;
+ }
+ }
+}
+
static int
process_comm_event(event_t *event, unsigned long offset, unsigned long head)
{
@@ -157,15 +222,16 @@ static void insert_caller_stat(unsigned long call_site,

static void process_alloc_event(struct raw_event_sample *raw,
struct event *event,
- int cpu __used,
+ int cpu,
u64 timestamp __used,
struct thread *thread __used,
- int node __used)
+ int node)
{
unsigned long call_site;
unsigned long ptr;
int bytes_req;
int bytes_alloc;
+ int node1, node2;

ptr = raw_field_value(event, "ptr", raw->data);
call_site = raw_field_value(event, "call_site", raw->data);
@@ -177,6 +243,14 @@ static void process_alloc_event(struct raw_event_sample *raw,

total_requested += bytes_req;
total_allocated += bytes_alloc;
+
+ if (node) {
+ node1 = cpunode_map[cpu];
+ node2 = raw_field_value(event, "node", raw->data);
+ if (node1 != node2)
+ nr_cross_allocs++;
+ }
+ nr_allocs++;
}

static void process_free_event(struct raw_event_sample *raw __used,
@@ -359,6 +433,7 @@ static void print_summary(void)
total_allocated - total_requested);
printf("Internal fragmentation: %f%%\n",
fragmentation(total_requested, total_allocated));
+ printf("Cross CPU allocations: %lu/%lu\n", nr_cross_allocs, nr_allocs);
}

static void print_result(void)
@@ -685,6 +760,8 @@ int cmd_kmem(int argc, const char **argv, const char *prefix __used)
if (list_empty(&alloc_sort))
setup_sorting(&alloc_sort, default_sort_order);

+ setup_cpunode_map();
+
return __cmd_kmem();
}

--
1.6.3