Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next

Pull networking updates from David Miller:
 "Highlights:

   1) Support more Realtek wireless chips, from Jes Sorenson.

   2) New BPF types for per-cpu hash and arrap maps, from Alexei
      Starovoitov.

   3) Make several TCP sysctls per-namespace, from Nikolay Borisov.

   4) Allow the use of SO_REUSEPORT in order to do per-thread processing
   of incoming TCP/UDP connections.  The muxing can be done using a
   BPF program which hashes the incoming packet.  From Craig Gallek.

   5) Add a multiplexer for TCP streams, to provide a messaged based
      interface.  BPF programs can be used to determine the message
      boundaries.  From Tom Herbert.

   6) Add 802.1AE MACSEC support, from Sabrina Dubroca.

   7) Avoid factorial complexity when taking down an inetdev interface
      with lots of configured addresses.  We were doing things like
      traversing the entire address less for each address removed, and
      flushing the entire netfilter conntrack table for every address as
      well.

   8) Add and use SKB bulk free infrastructure, from Jesper Brouer.

   9) Allow offloading u32 classifiers to hardware, and implement for
      ixgbe, from John Fastabend.

  10) Allow configuring IRQ coalescing parameters on a per-queue basis,
      from Kan Liang.

  11) Extend ethtool so that larger link mode masks can be supported.
      From David Decotigny.

  12) Introduce devlink, which can be used to configure port link types
      (ethernet vs Infiniband, etc.), port splitting, and switch device
      level attributes as a whole.  From Jiri Pirko.

  13) Hardware offload support for flower classifiers, from Amir Vadai.

  14) Add "Local Checksum Offload".  Basically, for a tunneled packet
      the checksum of the outer header is 'constant' (because with the
      checksum field filled into the inner protocol header, the payload
      of the outer frame checksums to 'zero'), and we can take advantage
      of that in various ways.  From Edward Cree"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1548 commits)
  bonding: fix bond_get_stats()
  net: bcmgenet: fix dma api length mismatch
  net/mlx4_core: Fix backward compatibility on VFs
  phy: mdio-thunder: Fix some Kconfig typos
  lan78xx: add ndo_get_stats64
  lan78xx: handle statistics counter rollover
  RDS: TCP: Remove unused constant
  RDS: TCP: Add sysctl tunables for sndbuf/rcvbuf on rds-tcp socket
  net: smc911x: convert pxa dma to dmaengine
  team: remove duplicate set of flag IFF_MULTICAST
  bonding: remove duplicate set of flag IFF_MULTICAST
  net: fix a comment typo
  ethernet: micrel: fix some error codes
  ip_tunnels, bpf: define IP_TUNNEL_OPTS_MAX and use it
  bpf, dst: add and use dst_tclassid helper
  bpf: make skb->tc_classid also readable
  net: mvneta: bm: clarify dependencies
  cls_bpf: reset class and reuse major in da
  ldmvsw: Checkpatch sunvnet.c and sunvnet_common.c
  ldmvsw: Add ldmvsw.c driver code
  ...

20 files changed, 952 insertions, 27 deletions

diff --git a/samples/bpf/Makefile b/samples/bpf/Makefile
index edd638b..502c9fc 100644
--- a/samples/bpf/Makefile
+++ b/samples/bpf/Makefile
@@ -16,6 +16,9 @@ hostprogs-y += tracex5
 hostprogs-y += tracex6
 hostprogs-y += trace_output
 hostprogs-y += lathist
+hostprogs-y += offwaketime
+hostprogs-y += spintest
+hostprogs-y += map_perf_test
 
 test_verifier-objs := test_verifier.o libbpf.o
 test_maps-objs := test_maps.o libbpf.o
@@ -32,6 +35,9 @@ tracex5-objs := bpf_load.o libbpf.o tracex5_user.o
 tracex6-objs := bpf_load.o libbpf.o tracex6_user.o
 trace_output-objs := bpf_load.o libbpf.o trace_output_user.o
 lathist-objs := bpf_load.o libbpf.o lathist_user.o
+offwaketime-objs := bpf_load.o libbpf.o offwaketime_user.o
+spintest-objs := bpf_load.o libbpf.o spintest_user.o
+map_perf_test-objs := bpf_load.o libbpf.o map_perf_test_user.o
 
 # Tell kbuild to always build the programs
 always := $(hostprogs-y)
@@ -47,6 +53,9 @@ always += tracex6_kern.o
 always += trace_output_kern.o
 always += tcbpf1_kern.o
 always += lathist_kern.o
+always += offwaketime_kern.o
+always += spintest_kern.o
+always += map_perf_test_kern.o
 
 HOSTCFLAGS += -I$(objtree)/usr/include
 
@@ -63,6 +72,9 @@ HOSTLOADLIBES_tracex5 += -lelf
 HOSTLOADLIBES_tracex6 += -lelf
 HOSTLOADLIBES_trace_output += -lelf -lrt
 HOSTLOADLIBES_lathist += -lelf
+HOSTLOADLIBES_offwaketime += -lelf
+HOSTLOADLIBES_spintest += -lelf
+HOSTLOADLIBES_map_perf_test += -lelf -lrt
 
 # point this to your LLVM backend with bpf support
 LLC=$(srctree)/tools/bpf/llvm/bld/Debug+Asserts/bin/llc
diff --git a/samples/bpf/bpf_helpers.h b/samples/bpf/bpf_helpers.h
index 7ad19e1..9363500 100644
--- a/samples/bpf/bpf_helpers.h
+++ b/samples/bpf/bpf_helpers.h
@@ -39,6 +39,8 @@ static int (*bpf_redirect)(int ifindex, int flags) =
 	(void *) BPF_FUNC_redirect;
 static int (*bpf_perf_event_output)(void *ctx, void *map, int index, void *data, int size) =
 	(void *) BPF_FUNC_perf_event_output;
+static int (*bpf_get_stackid)(void *ctx, void *map, int flags) =
+	(void *) BPF_FUNC_get_stackid;
 
 /* llvm builtin functions that eBPF C program may use to
  * emit BPF_LD_ABS and BPF_LD_IND instructions
@@ -59,6 +61,7 @@ struct bpf_map_def {
 	unsigned int key_size;
 	unsigned int value_size;
 	unsigned int max_entries;
+	unsigned int map_flags;
 };
 
 static int (*bpf_skb_store_bytes)(void *ctx, int off, void *from, int len, int flags) =
diff --git a/samples/bpf/bpf_load.c b/samples/bpf/bpf_load.c
index da86a8e..58f86bd 100644
--- a/samples/bpf/bpf_load.c
+++ b/samples/bpf/bpf_load.c
@@ -157,9 +157,13 @@ static int load_maps(struct bpf_map_def *maps, int len)
 		map_fd[i] = bpf_create_map(maps[i].type,
 					   maps[i].key_size,
 					   maps[i].value_size,
-					   maps[i].max_entries);
-		if (map_fd[i] < 0)
+					   maps[i].max_entries,
+					   maps[i].map_flags);
+		if (map_fd[i] < 0) {
+			printf("failed to create a map: %d %s\n",
+			       errno, strerror(errno));
 			return 1;
+		}
 
 		if (maps[i].type == BPF_MAP_TYPE_PROG_ARRAY)
 			prog_array_fd = map_fd[i];
@@ -343,3 +347,65 @@ void read_trace_pipe(void)
 		}
 	}
 }
+
+#define MAX_SYMS 300000
+static struct ksym syms[MAX_SYMS];
+static int sym_cnt;
+
+static int ksym_cmp(const void *p1, const void *p2)
+{
+	return ((struct ksym *)p1)->addr - ((struct ksym *)p2)->addr;
+}
+
+int load_kallsyms(void)
+{
+	FILE *f = fopen("/proc/kallsyms", "r");
+	char func[256], buf[256];
+	char symbol;
+	void *addr;
+	int i = 0;
+
+	if (!f)
+		return -ENOENT;
+
+	while (!feof(f)) {
+		if (!fgets(buf, sizeof(buf), f))
+			break;
+		if (sscanf(buf, "%p %c %s", &addr, &symbol, func) != 3)
+			break;
+		if (!addr)
+			continue;
+		syms[i].addr = (long) addr;
+		syms[i].name = strdup(func);
+		i++;
+	}
+	sym_cnt = i;
+	qsort(syms, sym_cnt, sizeof(struct ksym), ksym_cmp);
+	return 0;
+}
+
+struct ksym *ksym_search(long key)
+{
+	int start = 0, end = sym_cnt;
+	int result;
+
+	while (start < end) {
+		size_t mid = start + (end - start) / 2;
+
+		result = key - syms[mid].addr;
+		if (result < 0)
+			end = mid;
+		else if (result > 0)
+			start = mid + 1;
+		else
+			return &syms[mid];
+	}
+
+	if (start >= 1 && syms[start - 1].addr < key &&
+	    key < syms[start].addr)
+		/* valid ksym */
+		return &syms[start - 1];
+
+	/* out of range. return _stext */
+	return &syms[0];
+}
diff --git a/samples/bpf/bpf_load.h b/samples/bpf/bpf_load.h
index cbd7c2b..dfa57fe 100644
--- a/samples/bpf/bpf_load.h
+++ b/samples/bpf/bpf_load.h
@@ -23,5 +23,11 @@ extern int event_fd[MAX_PROGS];
 int load_bpf_file(char *path);
 
 void read_trace_pipe(void);
+struct ksym {
+	long addr;
+	char *name;
+};
 
+int load_kallsyms(void);
+struct ksym *ksym_search(long key);
 #endif
diff --git a/samples/bpf/fds_example.c b/samples/bpf/fds_example.c
index e2fd16c..625e797 100644
--- a/samples/bpf/fds_example.c
+++ b/samples/bpf/fds_example.c
@@ -44,7 +44,7 @@ static void usage(void)
 static int bpf_map_create(void)
 {
 	return bpf_create_map(BPF_MAP_TYPE_ARRAY, sizeof(uint32_t),
-			      sizeof(uint32_t), 1024);
+			      sizeof(uint32_t), 1024, 0);
 }
 
 static int bpf_prog_create(const char *object)
diff --git a/samples/bpf/libbpf.c b/samples/bpf/libbpf.c
index 65a8d48..9969e35 100644
--- a/samples/bpf/libbpf.c
+++ b/samples/bpf/libbpf.c
@@ -19,13 +19,14 @@ static __u64 ptr_to_u64(void *ptr)
 }
 
 int bpf_create_map(enum bpf_map_type map_type, int key_size, int value_size,
-		   int max_entries)
+		   int max_entries, int map_flags)
 {
 	union bpf_attr attr = {
 		.map_type = map_type,
 		.key_size = key_size,
 		.value_size = value_size,
-		.max_entries = max_entries
+		.max_entries = max_entries,
+		.map_flags = map_flags,
 	};
 
 	return syscall(__NR_bpf, BPF_MAP_CREATE, &attr, sizeof(attr));
diff --git a/samples/bpf/libbpf.h b/samples/bpf/libbpf.h
index 014aacf..364582b 100644
--- a/samples/bpf/libbpf.h
+++ b/samples/bpf/libbpf.h
@@ -5,7 +5,7 @@
 struct bpf_insn;
 
 int bpf_create_map(enum bpf_map_type map_type, int key_size, int value_size,
-		   int max_entries);
+		   int max_entries, int map_flags);
 int bpf_update_elem(int fd, void *key, void *value, unsigned long long flags);
 int bpf_lookup_elem(int fd, void *key, void *value);
 int bpf_delete_elem(int fd, void *key);
diff --git a/samples/bpf/map_perf_test_kern.c b/samples/bpf/map_perf_test_kern.c
new file mode 100644
index 0000000..311538e
--- /dev/null
+++ b/samples/bpf/map_perf_test_kern.c
@@ -0,0 +1,100 @@
+/* Copyright (c) 2016 Facebook
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ */
+#include <linux/skbuff.h>
+#include <linux/netdevice.h>
+#include <linux/version.h>
+#include <uapi/linux/bpf.h>
+#include "bpf_helpers.h"
+
+#define MAX_ENTRIES 1000
+
+struct bpf_map_def SEC("maps") hash_map = {
+	.type = BPF_MAP_TYPE_HASH,
+	.key_size = sizeof(u32),
+	.value_size = sizeof(long),
+	.max_entries = MAX_ENTRIES,
+};
+
+struct bpf_map_def SEC("maps") percpu_hash_map = {
+	.type = BPF_MAP_TYPE_PERCPU_HASH,
+	.key_size = sizeof(u32),
+	.value_size = sizeof(long),
+	.max_entries = MAX_ENTRIES,
+};
+
+struct bpf_map_def SEC("maps") hash_map_alloc = {
+	.type = BPF_MAP_TYPE_HASH,
+	.key_size = sizeof(u32),
+	.value_size = sizeof(long),
+	.max_entries = MAX_ENTRIES,
+	.map_flags = BPF_F_NO_PREALLOC,
+};
+
+struct bpf_map_def SEC("maps") percpu_hash_map_alloc = {
+	.type = BPF_MAP_TYPE_PERCPU_HASH,
+	.key_size = sizeof(u32),
+	.value_size = sizeof(long),
+	.max_entries = MAX_ENTRIES,
+	.map_flags = BPF_F_NO_PREALLOC,
+};
+
+SEC("kprobe/sys_getuid")
+int stress_hmap(struct pt_regs *ctx)
+{
+	u32 key = bpf_get_current_pid_tgid();
+	long init_val = 1;
+	long *value;
+
+	bpf_map_update_elem(&hash_map, &key, &init_val, BPF_ANY);
+	value = bpf_map_lookup_elem(&hash_map, &key);
+	if (value)
+		bpf_map_delete_elem(&hash_map, &key);
+	return 0;
+}
+
+SEC("kprobe/sys_geteuid")
+int stress_percpu_hmap(struct pt_regs *ctx)
+{
+	u32 key = bpf_get_current_pid_tgid();
+	long init_val = 1;
+	long *value;
+
+	bpf_map_update_elem(&percpu_hash_map, &key, &init_val, BPF_ANY);
+	value = bpf_map_lookup_elem(&percpu_hash_map, &key);
+	if (value)
+		bpf_map_delete_elem(&percpu_hash_map, &key);
+	return 0;
+}
+SEC("kprobe/sys_getgid")
+int stress_hmap_alloc(struct pt_regs *ctx)
+{
+	u32 key = bpf_get_current_pid_tgid();
+	long init_val = 1;
+	long *value;
+
+	bpf_map_update_elem(&hash_map_alloc, &key, &init_val, BPF_ANY);
+	value = bpf_map_lookup_elem(&hash_map_alloc, &key);
+	if (value)
+		bpf_map_delete_elem(&hash_map_alloc, &key);
+	return 0;
+}
+
+SEC("kprobe/sys_getegid")
+int stress_percpu_hmap_alloc(struct pt_regs *ctx)
+{
+	u32 key = bpf_get_current_pid_tgid();
+	long init_val = 1;
+	long *value;
+
+	bpf_map_update_elem(&percpu_hash_map_alloc, &key, &init_val, BPF_ANY);
+	value = bpf_map_lookup_elem(&percpu_hash_map_alloc, &key);
+	if (value)
+		bpf_map_delete_elem(&percpu_hash_map_alloc, &key);
+	return 0;
+}
+char _license[] SEC("license") = "GPL";
+u32 _version SEC("version") = LINUX_VERSION_CODE;
diff --git a/samples/bpf/map_perf_test_user.c b/samples/bpf/map_perf_test_user.c
new file mode 100644
index 0000000..95af56e
--- /dev/null
+++ b/samples/bpf/map_perf_test_user.c
@@ -0,0 +1,155 @@
+/* Copyright (c) 2016 Facebook
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ */
+#define _GNU_SOURCE
+#include <sched.h>
+#include <stdio.h>
+#include <sys/types.h>
+#include <asm/unistd.h>
+#include <unistd.h>
+#include <assert.h>
+#include <sys/wait.h>
+#include <stdlib.h>
+#include <signal.h>
+#include <linux/bpf.h>
+#include <string.h>
+#include <time.h>
+#include "libbpf.h"
+#include "bpf_load.h"
+
+#define MAX_CNT 1000000
+
+static __u64 time_get_ns(void)
+{
+	struct timespec ts;
+
+	clock_gettime(CLOCK_MONOTONIC, &ts);
+	return ts.tv_sec * 1000000000ull + ts.tv_nsec;
+}
+
+#define HASH_PREALLOC		(1 << 0)
+#define PERCPU_HASH_PREALLOC	(1 << 1)
+#define HASH_KMALLOC		(1 << 2)
+#define PERCPU_HASH_KMALLOC	(1 << 3)
+
+static int test_flags = ~0;
+
+static void test_hash_prealloc(int cpu)
+{
+	__u64 start_time;
+	int i;
+
+	start_time = time_get_ns();
+	for (i = 0; i < MAX_CNT; i++)
+		syscall(__NR_getuid);
+	printf("%d:hash_map_perf pre-alloc %lld events per sec\n",
+	       cpu, MAX_CNT * 1000000000ll / (time_get_ns() - start_time));
+}
+
+static void test_percpu_hash_prealloc(int cpu)
+{
+	__u64 start_time;
+	int i;
+
+	start_time = time_get_ns();
+	for (i = 0; i < MAX_CNT; i++)
+		syscall(__NR_geteuid);
+	printf("%d:percpu_hash_map_perf pre-alloc %lld events per sec\n",
+	       cpu, MAX_CNT * 1000000000ll / (time_get_ns() - start_time));
+}
+
+static void test_hash_kmalloc(int cpu)
+{
+	__u64 start_time;
+	int i;
+
+	start_time = time_get_ns();
+	for (i = 0; i < MAX_CNT; i++)
+		syscall(__NR_getgid);
+	printf("%d:hash_map_perf kmalloc %lld events per sec\n",
+	       cpu, MAX_CNT * 1000000000ll / (time_get_ns() - start_time));
+}
+
+static void test_percpu_hash_kmalloc(int cpu)
+{
+	__u64 start_time;
+	int i;
+
+	start_time = time_get_ns();
+	for (i = 0; i < MAX_CNT; i++)
+		syscall(__NR_getegid);
+	printf("%d:percpu_hash_map_perf kmalloc %lld events per sec\n",
+	       cpu, MAX_CNT * 1000000000ll / (time_get_ns() - start_time));
+}
+
+static void loop(int cpu)
+{
+	cpu_set_t cpuset;
+
+	CPU_ZERO(&cpuset);
+	CPU_SET(cpu, &cpuset);
+	sched_setaffinity(0, sizeof(cpuset), &cpuset);
+
+	if (test_flags & HASH_PREALLOC)
+		test_hash_prealloc(cpu);
+
+	if (test_flags & PERCPU_HASH_PREALLOC)
+		test_percpu_hash_prealloc(cpu);
+
+	if (test_flags & HASH_KMALLOC)
+		test_hash_kmalloc(cpu);
+
+	if (test_flags & PERCPU_HASH_KMALLOC)
+		test_percpu_hash_kmalloc(cpu);
+}
+
+static void run_perf_test(int tasks)
+{
+	pid_t pid[tasks];
+	int i;
+
+	for (i = 0; i < tasks; i++) {
+		pid[i] = fork();
+		if (pid[i] == 0) {
+			loop(i);
+			exit(0);
+		} else if (pid[i] == -1) {
+			printf("couldn't spawn #%d process\n", i);
+			exit(1);
+		}
+	}
+	for (i = 0; i < tasks; i++) {
+		int status;
+
+		assert(waitpid(pid[i], &status, 0) == pid[i]);
+		assert(status == 0);
+	}
+}
+
+int main(int argc, char **argv)
+{
+	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
+	char filename[256];
+	int num_cpu = 8;
+
+	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
+	setrlimit(RLIMIT_MEMLOCK, &r);
+
+	if (argc > 1)
+		test_flags = atoi(argv[1]) ? : test_flags;
+
+	if (argc > 2)
+		num_cpu = atoi(argv[2]) ? : num_cpu;
+
+	if (load_bpf_file(filename)) {
+		printf("%s", bpf_log_buf);
+		return 1;
+	}
+
+	run_perf_test(num_cpu);
+
+	return 0;
+}
diff --git a/samples/bpf/offwaketime_kern.c b/samples/bpf/offwaketime_kern.c
new file mode 100644
index 0000000..c0aa5a9
--- /dev/null
+++ b/samples/bpf/offwaketime_kern.c
@@ -0,0 +1,131 @@
+/* Copyright (c) 2016 Facebook
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ */
+#include <uapi/linux/bpf.h>
+#include "bpf_helpers.h"
+#include <uapi/linux/ptrace.h>
+#include <uapi/linux/perf_event.h>
+#include <linux/version.h>
+#include <linux/sched.h>
+
+#define _(P) ({typeof(P) val = 0; bpf_probe_read(&val, sizeof(val), &P); val;})
+
+#define MINBLOCK_US	1
+
+struct key_t {
+	char waker[TASK_COMM_LEN];
+	char target[TASK_COMM_LEN];
+	u32 wret;
+	u32 tret;
+};
+
+struct bpf_map_def SEC("maps") counts = {
+	.type = BPF_MAP_TYPE_HASH,
+	.key_size = sizeof(struct key_t),
+	.value_size = sizeof(u64),
+	.max_entries = 10000,
+};
+
+struct bpf_map_def SEC("maps") start = {
+	.type = BPF_MAP_TYPE_HASH,
+	.key_size = sizeof(u32),
+	.value_size = sizeof(u64),
+	.max_entries = 10000,
+};
+
+struct wokeby_t {
+	char name[TASK_COMM_LEN];
+	u32 ret;
+};
+
+struct bpf_map_def SEC("maps") wokeby = {
+	.type = BPF_MAP_TYPE_HASH,
+	.key_size = sizeof(u32),
+	.value_size = sizeof(struct wokeby_t),
+	.max_entries = 10000,
+};
+
+struct bpf_map_def SEC("maps") stackmap = {
+	.type = BPF_MAP_TYPE_STACK_TRACE,
+	.key_size = sizeof(u32),
+	.value_size = PERF_MAX_STACK_DEPTH * sizeof(u64),
+	.max_entries = 10000,
+};
+
+#define STACKID_FLAGS (0 | BPF_F_FAST_STACK_CMP)
+
+SEC("kprobe/try_to_wake_up")
+int waker(struct pt_regs *ctx)
+{
+	struct task_struct *p = (void *) PT_REGS_PARM1(ctx);
+	struct wokeby_t woke = {};
+	u32 pid;
+
+	pid = _(p->pid);
+
+	bpf_get_current_comm(&woke.name, sizeof(woke.name));
+	woke.ret = bpf_get_stackid(ctx, &stackmap, STACKID_FLAGS);
+
+	bpf_map_update_elem(&wokeby, &pid, &woke, BPF_ANY);
+	return 0;
+}
+
+static inline int update_counts(struct pt_regs *ctx, u32 pid, u64 delta)
+{
+	struct key_t key = {};
+	struct wokeby_t *woke;
+	u64 zero = 0, *val;
+
+	bpf_get_current_comm(&key.target, sizeof(key.target));
+	key.tret = bpf_get_stackid(ctx, &stackmap, STACKID_FLAGS);
+
+	woke = bpf_map_lookup_elem(&wokeby, &pid);
+	if (woke) {
+		key.wret = woke->ret;
+		__builtin_memcpy(&key.waker, woke->name, TASK_COMM_LEN);
+		bpf_map_delete_elem(&wokeby, &pid);
+	}
+
+	val = bpf_map_lookup_elem(&counts, &key);
+	if (!val) {
+		bpf_map_update_elem(&counts, &key, &zero, BPF_NOEXIST);
+		val = bpf_map_lookup_elem(&counts, &key);
+		if (!val)
+			return 0;
+	}
+	(*val) += delta;
+	return 0;
+}
+
+SEC("kprobe/finish_task_switch")
+int oncpu(struct pt_regs *ctx)
+{
+	struct task_struct *p = (void *) PT_REGS_PARM1(ctx);
+	u64 delta, ts, *tsp;
+	u32 pid;
+
+	/* record previous thread sleep time */
+	pid = _(p->pid);
+	ts = bpf_ktime_get_ns();
+	bpf_map_update_elem(&start, &pid, &ts, BPF_ANY);
+
+	/* calculate current thread's delta time */
+	pid = bpf_get_current_pid_tgid();
+	tsp = bpf_map_lookup_elem(&start, &pid);
+	if (!tsp)
+		/* missed start or filtered */
+		return 0;
+
+	delta = bpf_ktime_get_ns() - *tsp;
+	bpf_map_delete_elem(&start, &pid);
+	delta = delta / 1000;
+	if (delta < MINBLOCK_US)
+		return 0;
+
+	return update_counts(ctx, pid, delta);
+}
+char _license[] SEC("license") = "GPL";
+u32 _version SEC("version") = LINUX_VERSION_CODE;
diff --git a/samples/bpf/offwaketime_user.c b/samples/bpf/offwaketime_user.c
new file mode 100644
index 0000000..6f002a9
--- /dev/null
+++ b/samples/bpf/offwaketime_user.c
@@ -0,0 +1,120 @@
+/* Copyright (c) 2016 Facebook
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ */
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <signal.h>
+#include <linux/bpf.h>
+#include <string.h>
+#include <linux/perf_event.h>
+#include <errno.h>
+#include <assert.h>
+#include <stdbool.h>
+#include <sys/resource.h>
+#include "libbpf.h"
+#include "bpf_load.h"
+
+#define PRINT_RAW_ADDR 0
+
+static void print_ksym(__u64 addr)
+{
+	struct ksym *sym;
+
+	if (!addr)
+		return;
+	sym = ksym_search(addr);
+	if (PRINT_RAW_ADDR)
+		printf("%s/%llx;", sym->name, addr);
+	else
+		printf("%s;", sym->name);
+}
+
+#define TASK_COMM_LEN 16
+
+struct key_t {
+	char waker[TASK_COMM_LEN];
+	char target[TASK_COMM_LEN];
+	__u32 wret;
+	__u32 tret;
+};
+
+static void print_stack(struct key_t *key, __u64 count)
+{
+	__u64 ip[PERF_MAX_STACK_DEPTH] = {};
+	static bool warned;
+	int i;
+
+	printf("%s;", key->target);
+	if (bpf_lookup_elem(map_fd[3], &key->tret, ip) != 0) {
+		printf("---;");
+	} else {
+		for (i = PERF_MAX_STACK_DEPTH - 1; i >= 0; i--)
+			print_ksym(ip[i]);
+	}
+	printf("-;");
+	if (bpf_lookup_elem(map_fd[3], &key->wret, ip) != 0) {
+		printf("---;");
+	} else {
+		for (i = 0; i < PERF_MAX_STACK_DEPTH; i++)
+			print_ksym(ip[i]);
+	}
+	printf(";%s %lld\n", key->waker, count);
+
+	if ((key->tret == -EEXIST || key->wret == -EEXIST) && !warned) {
+		printf("stackmap collisions seen. Consider increasing size\n");
+		warned = true;
+	} else if (((int)(key->tret) < 0 || (int)(key->wret) < 0)) {
+		printf("err stackid %d %d\n", key->tret, key->wret);
+	}
+}
+
+static void print_stacks(int fd)
+{
+	struct key_t key = {}, next_key;
+	__u64 value;
+
+	while (bpf_get_next_key(fd, &key, &next_key) == 0) {
+		bpf_lookup_elem(fd, &next_key, &value);
+		print_stack(&next_key, value);
+		key = next_key;
+	}
+}
+
+static void int_exit(int sig)
+{
+	print_stacks(map_fd[0]);
+	exit(0);
+}
+
+int main(int argc, char **argv)
+{
+	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
+	char filename[256];
+	int delay = 1;
+
+	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
+	setrlimit(RLIMIT_MEMLOCK, &r);
+
+	signal(SIGINT, int_exit);
+
+	if (load_kallsyms()) {
+		printf("failed to process /proc/kallsyms\n");
+		return 2;
+	}
+
+	if (load_bpf_file(filename)) {
+		printf("%s", bpf_log_buf);
+		return 1;
+	}
+
+	if (argc > 1)
+		delay = atoi(argv[1]);
+	sleep(delay);
+	print_stacks(map_fd[0]);
+
+	return 0;
+}
diff --git a/samples/bpf/sock_example.c b/samples/bpf/sock_example.c
index a0ce251..28b60ba 100644
--- a/samples/bpf/sock_example.c
+++ b/samples/bpf/sock_example.c
@@ -34,7 +34,7 @@ static int test_sock(void)
 	long long value = 0, tcp_cnt, udp_cnt, icmp_cnt;
 
 	map_fd = bpf_create_map(BPF_MAP_TYPE_ARRAY, sizeof(key), sizeof(value),
-				256);
+				256, 0);
 	if (map_fd < 0) {
 		printf("failed to create map '%s'\n", strerror(errno));
 		goto cleanup;
diff --git a/samples/bpf/spintest_kern.c b/samples/bpf/spintest_kern.c
new file mode 100644
index 0000000..4b27619
--- /dev/null
+++ b/samples/bpf/spintest_kern.c
@@ -0,0 +1,68 @@
+/* Copyright (c) 2016, Facebook
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ */
+#include <linux/skbuff.h>
+#include <linux/netdevice.h>
+#include <linux/version.h>
+#include <uapi/linux/bpf.h>
+#include <uapi/linux/perf_event.h>
+#include "bpf_helpers.h"
+
+struct bpf_map_def SEC("maps") my_map = {
+	.type = BPF_MAP_TYPE_HASH,
+	.key_size = sizeof(long),
+	.value_size = sizeof(long),
+	.max_entries = 1024,
+};
+struct bpf_map_def SEC("maps") my_map2 = {
+	.type = BPF_MAP_TYPE_PERCPU_HASH,
+	.key_size = sizeof(long),
+	.value_size = sizeof(long),
+	.max_entries = 1024,
+};
+
+struct bpf_map_def SEC("maps") stackmap = {
+	.type = BPF_MAP_TYPE_STACK_TRACE,
+	.key_size = sizeof(u32),
+	.value_size = PERF_MAX_STACK_DEPTH * sizeof(u64),
+	.max_entries = 10000,
+};
+
+#define PROG(foo) \
+int foo(struct pt_regs *ctx) \
+{ \
+	long v = ctx->ip, *val; \
+\
+	val = bpf_map_lookup_elem(&my_map, &v); \
+	bpf_map_update_elem(&my_map, &v, &v, BPF_ANY); \
+	bpf_map_update_elem(&my_map2, &v, &v, BPF_ANY); \
+	bpf_map_delete_elem(&my_map2, &v); \
+	bpf_get_stackid(ctx, &stackmap, BPF_F_REUSE_STACKID); \
+	return 0; \
+}
+
+/* add kprobes to all possible *spin* functions */
+SEC("kprobe/spin_unlock")PROG(p1)
+SEC("kprobe/spin_lock")PROG(p2)
+SEC("kprobe/mutex_spin_on_owner")PROG(p3)
+SEC("kprobe/rwsem_spin_on_owner")PROG(p4)
+SEC("kprobe/spin_unlock_irqrestore")PROG(p5)
+SEC("kprobe/_raw_spin_unlock_irqrestore")PROG(p6)
+SEC("kprobe/_raw_spin_unlock_bh")PROG(p7)
+SEC("kprobe/_raw_spin_unlock")PROG(p8)
+SEC("kprobe/_raw_spin_lock_irqsave")PROG(p9)
+SEC("kprobe/_raw_spin_trylock_bh")PROG(p10)
+SEC("kprobe/_raw_spin_lock_irq")PROG(p11)
+SEC("kprobe/_raw_spin_trylock")PROG(p12)
+SEC("kprobe/_raw_spin_lock")PROG(p13)
+SEC("kprobe/_raw_spin_lock_bh")PROG(p14)
+/* and to inner bpf helpers */
+SEC("kprobe/htab_map_update_elem")PROG(p15)
+SEC("kprobe/__htab_percpu_map_update_elem")PROG(p16)
+SEC("kprobe/htab_map_alloc")PROG(p17)
+
+char _license[] SEC("license") = "GPL";
+u32 _version SEC("version") = LINUX_VERSION_CODE;
diff --git a/samples/bpf/spintest_user.c b/samples/bpf/spintest_user.c
new file mode 100644
index 0000000..311ede5
--- /dev/null
+++ b/samples/bpf/spintest_user.c
@@ -0,0 +1,50 @@
+#include <stdio.h>
+#include <unistd.h>
+#include <linux/bpf.h>
+#include <string.h>
+#include <assert.h>
+#include <sys/resource.h>
+#include "libbpf.h"
+#include "bpf_load.h"
+
+int main(int ac, char **argv)
+{
+	struct rlimit r = {RLIM_INFINITY, RLIM_INFINITY};
+	long key, next_key, value;
+	char filename[256];
+	struct ksym *sym;
+	int i;
+
+	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
+	setrlimit(RLIMIT_MEMLOCK, &r);
+
+	if (load_kallsyms()) {
+		printf("failed to process /proc/kallsyms\n");
+		return 2;
+	}
+
+	if (load_bpf_file(filename)) {
+		printf("%s", bpf_log_buf);
+		return 1;
+	}
+
+	for (i = 0; i < 5; i++) {
+		key = 0;
+		printf("kprobing funcs:");
+		while (bpf_get_next_key(map_fd[0], &key, &next_key) == 0) {
+			bpf_lookup_elem(map_fd[0], &next_key, &value);
+			assert(next_key == value);
+			sym = ksym_search(value);
+			printf(" %s", sym->name);
+			key = next_key;
+		}
+		if (key)
+			printf("\n");
+		key = 0;
+		while (bpf_get_next_key(map_fd[0], &key, &next_key) == 0)
+			bpf_delete_elem(map_fd[0], &next_key);
+		sleep(1);
+	}
+
+	return 0;
+}
diff --git a/samples/bpf/test_maps.c b/samples/bpf/test_maps.c
index 6299ee9..47bf085 100644
--- a/samples/bpf/test_maps.c
+++ b/samples/bpf/test_maps.c
@@ -2,6 +2,7 @@
  * Testsuite for eBPF maps
  *
  * Copyright (c) 2014 PLUMgrid, http://plumgrid.com
+ * Copyright (c) 2016 Facebook
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of version 2 of the GNU General Public
@@ -17,13 +18,16 @@
 #include <stdlib.h>
 #include "libbpf.h"
 
+static int map_flags;
+
 /* sanity tests for map API */
 static void test_hashmap_sanity(int i, void *data)
 {
 	long long key, next_key, value;
 	int map_fd;
 
-	map_fd = bpf_create_map(BPF_MAP_TYPE_HASH, sizeof(key), sizeof(value), 2);
+	map_fd = bpf_create_map(BPF_MAP_TYPE_HASH, sizeof(key), sizeof(value),
+				2, map_flags);
 	if (map_fd < 0) {
 		printf("failed to create hashmap '%s'\n", strerror(errno));
 		exit(1);
@@ -89,12 +93,107 @@ static void test_hashmap_sanity(int i, void *data)
 	close(map_fd);
 }
 
+/* sanity tests for percpu map API */
+static void test_percpu_hashmap_sanity(int task, void *data)
+{
+	long long key, next_key;
+	int expected_key_mask = 0;
+	unsigned int nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
+	long long value[nr_cpus];
+	int map_fd, i;
+
+	map_fd = bpf_create_map(BPF_MAP_TYPE_PERCPU_HASH, sizeof(key),
+				sizeof(value[0]), 2, map_flags);
+	if (map_fd < 0) {
+		printf("failed to create hashmap '%s'\n", strerror(errno));
+		exit(1);
+	}
+
+	for (i = 0; i < nr_cpus; i++)
+		value[i] = i + 100;
+	key = 1;
+	/* insert key=1 element */
+	assert(!(expected_key_mask & key));
+	assert(bpf_update_elem(map_fd, &key, value, BPF_ANY) == 0);
+	expected_key_mask |= key;
+
+	/* BPF_NOEXIST means: add new element if it doesn't exist */
+	assert(bpf_update_elem(map_fd, &key, value, BPF_NOEXIST) == -1 &&
+	       /* key=1 already exists */
+	       errno == EEXIST);
+
+	/* -1 is an invalid flag */
+	assert(bpf_update_elem(map_fd, &key, value, -1) == -1 &&
+	       errno == EINVAL);
+
+	/* check that key=1 can be found. value could be 0 if the lookup
+	 * was run from a different cpu.
+	 */
+	value[0] = 1;
+	assert(bpf_lookup_elem(map_fd, &key, value) == 0 && value[0] == 100);
+
+	key = 2;
+	/* check that key=2 is not found */
+	assert(bpf_lookup_elem(map_fd, &key, value) == -1 && errno == ENOENT);
+
+	/* BPF_EXIST means: update existing element */
+	assert(bpf_update_elem(map_fd, &key, value, BPF_EXIST) == -1 &&
+	       /* key=2 is not there */
+	       errno == ENOENT);
+
+	/* insert key=2 element */
+	assert(!(expected_key_mask & key));
+	assert(bpf_update_elem(map_fd, &key, value, BPF_NOEXIST) == 0);
+	expected_key_mask |= key;
+
+	/* key=1 and key=2 were inserted, check that key=0 cannot be inserted
+	 * due to max_entries limit
+	 */
+	key = 0;
+	assert(bpf_update_elem(map_fd, &key, value, BPF_NOEXIST) == -1 &&
+	       errno == E2BIG);
+
+	/* check that key = 0 doesn't exist */
+	assert(bpf_delete_elem(map_fd, &key) == -1 && errno == ENOENT);
+
+	/* iterate over two elements */
+	while (!bpf_get_next_key(map_fd, &key, &next_key)) {
+		assert((expected_key_mask & next_key) == next_key);
+		expected_key_mask &= ~next_key;
+
+		assert(bpf_lookup_elem(map_fd, &next_key, value) == 0);
+		for (i = 0; i < nr_cpus; i++)
+			assert(value[i] == i + 100);
+
+		key = next_key;
+	}
+	assert(errno == ENOENT);
+
+	/* Update with BPF_EXIST */
+	key = 1;
+	assert(bpf_update_elem(map_fd, &key, value, BPF_EXIST) == 0);
+
+	/* delete both elements */
+	key = 1;
+	assert(bpf_delete_elem(map_fd, &key) == 0);
+	key = 2;
+	assert(bpf_delete_elem(map_fd, &key) == 0);
+	assert(bpf_delete_elem(map_fd, &key) == -1 && errno == ENOENT);
+
+	key = 0;
+	/* check that map is empty */
+	assert(bpf_get_next_key(map_fd, &key, &next_key) == -1 &&
+	       errno == ENOENT);
+	close(map_fd);
+}
+
 static void test_arraymap_sanity(int i, void *data)
 {
 	int key, next_key, map_fd;
 	long long value;
 
-	map_fd = bpf_create_map(BPF_MAP_TYPE_ARRAY, sizeof(key), sizeof(value), 2);
+	map_fd = bpf_create_map(BPF_MAP_TYPE_ARRAY, sizeof(key), sizeof(value),
+				2, 0);
 	if (map_fd < 0) {
 		printf("failed to create arraymap '%s'\n", strerror(errno));
 		exit(1);
@@ -142,6 +241,94 @@ static void test_arraymap_sanity(int i, void *data)
 	close(map_fd);
 }
 
+static void test_percpu_arraymap_many_keys(void)
+{
+	unsigned nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
+	unsigned nr_keys = 20000;
+	long values[nr_cpus];
+	int key, map_fd, i;
+
+	map_fd = bpf_create_map(BPF_MAP_TYPE_PERCPU_ARRAY, sizeof(key),
+				sizeof(values[0]), nr_keys, 0);
+	if (map_fd < 0) {
+		printf("failed to create per-cpu arraymap '%s'\n",
+		       strerror(errno));
+		exit(1);
+	}
+
+	for (i = 0; i < nr_cpus; i++)
+		values[i] = i + 10;
+
+	for (key = 0; key < nr_keys; key++)
+		assert(bpf_update_elem(map_fd, &key, values, BPF_ANY) == 0);
+
+	for (key = 0; key < nr_keys; key++) {
+		for (i = 0; i < nr_cpus; i++)
+			values[i] = 0;
+		assert(bpf_lookup_elem(map_fd, &key, values) == 0);
+		for (i = 0; i < nr_cpus; i++)
+			assert(values[i] == i + 10);
+	}
+
+	close(map_fd);
+}
+
+static void test_percpu_arraymap_sanity(int i, void *data)
+{
+	unsigned nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
+	long values[nr_cpus];
+	int key, next_key, map_fd;
+
+	map_fd = bpf_create_map(BPF_MAP_TYPE_PERCPU_ARRAY, sizeof(key),
+				sizeof(values[0]), 2, 0);
+	if (map_fd < 0) {
+		printf("failed to create arraymap '%s'\n", strerror(errno));
+		exit(1);
+	}
+
+	for (i = 0; i < nr_cpus; i++)
+		values[i] = i + 100;
+
+	key = 1;
+	/* insert key=1 element */
+	assert(bpf_update_elem(map_fd, &key, values, BPF_ANY) == 0);
+
+	values[0] = 0;
+	assert(bpf_update_elem(map_fd, &key, values, BPF_NOEXIST) == -1 &&
+	       errno == EEXIST);
+
+	/* check that key=1 can be found */
+	assert(bpf_lookup_elem(map_fd, &key, values) == 0 && values[0] == 100);
+
+	key = 0;
+	/* check that key=0 is also found and zero initialized */
+	assert(bpf_lookup_elem(map_fd, &key, values) == 0 &&
+	       values[0] == 0 && values[nr_cpus - 1] == 0);
+
+
+	/* check that key=2 cannot be inserted due to max_entries limit */
+	key = 2;
+	assert(bpf_update_elem(map_fd, &key, values, BPF_EXIST) == -1 &&
+	       errno == E2BIG);
+
+	/* check that key = 2 doesn't exist */
+	assert(bpf_lookup_elem(map_fd, &key, values) == -1 && errno == ENOENT);
+
+	/* iterate over two elements */
+	assert(bpf_get_next_key(map_fd, &key, &next_key) == 0 &&
+	       next_key == 0);
+	assert(bpf_get_next_key(map_fd, &next_key, &next_key) == 0 &&
+	       next_key == 1);
+	assert(bpf_get_next_key(map_fd, &next_key, &next_key) == -1 &&
+	       errno == ENOENT);
+
+	/* delete shouldn't succeed */
+	key = 1;
+	assert(bpf_delete_elem(map_fd, &key) == -1 && errno == EINVAL);
+
+	close(map_fd);
+}
+
 #define MAP_SIZE (32 * 1024)
 static void test_map_large(void)
 {
@@ -154,7 +341,7 @@ static void test_map_large(void)
 
 	/* allocate 4Mbyte of memory */
 	map_fd = bpf_create_map(BPF_MAP_TYPE_HASH, sizeof(key), sizeof(value),
-				MAP_SIZE);
+				MAP_SIZE, map_flags);
 	if (map_fd < 0) {
 		printf("failed to create large map '%s'\n", strerror(errno));
 		exit(1);
@@ -209,7 +396,9 @@ static void run_parallel(int tasks, void (*fn)(int i, void *data), void *data)
 static void test_map_stress(void)
 {
 	run_parallel(100, test_hashmap_sanity, NULL);
+	run_parallel(100, test_percpu_hashmap_sanity, NULL);
 	run_parallel(100, test_arraymap_sanity, NULL);
+	run_parallel(100, test_percpu_arraymap_sanity, NULL);
 }
 
 #define TASKS 1024
@@ -237,7 +426,7 @@ static void test_map_parallel(void)
 	int data[2];
 
 	map_fd = bpf_create_map(BPF_MAP_TYPE_HASH, sizeof(key), sizeof(value),
-				MAP_SIZE);
+				MAP_SIZE, map_flags);
 	if (map_fd < 0) {
 		printf("failed to create map for parallel test '%s'\n",
 		       strerror(errno));
@@ -279,13 +468,25 @@ static void test_map_parallel(void)
 	assert(bpf_get_next_key(map_fd, &key, &key) == -1 && errno == ENOENT);
 }
 
-int main(void)
+static void run_all_tests(void)
 {
 	test_hashmap_sanity(0, NULL);
+	test_percpu_hashmap_sanity(0, NULL);
 	test_arraymap_sanity(0, NULL);
+	test_percpu_arraymap_sanity(0, NULL);
+	test_percpu_arraymap_many_keys();
+
 	test_map_large();
 	test_map_parallel();
 	test_map_stress();
+}
+
+int main(void)
+{
+	map_flags = 0;
+	run_all_tests();
+	map_flags = BPF_F_NO_PREALLOC;
+	run_all_tests();
 	printf("test_maps: OK\n");
 	return 0;
 }
diff --git a/samples/bpf/test_verifier.c b/samples/bpf/test_verifier.c
index 563c507..4b51a90 100644
--- a/samples/bpf/test_verifier.c
+++ b/samples/bpf/test_verifier.c
@@ -1198,7 +1198,7 @@ static int create_map(void)
 	int map_fd;
 
 	map_fd = bpf_create_map(BPF_MAP_TYPE_HASH,
-				sizeof(long long), sizeof(long long), 1024);
+				sizeof(long long), sizeof(long long), 1024, 0);
 	if (map_fd < 0)
 		printf("failed to create map '%s'\n", strerror(errno));
 
@@ -1210,7 +1210,7 @@ static int create_prog_array(void)
 	int map_fd;
 
 	map_fd = bpf_create_map(BPF_MAP_TYPE_PROG_ARRAY,
-				sizeof(int), sizeof(int), 4);
+				sizeof(int), sizeof(int), 4, 0);
 	if (map_fd < 0)
 		printf("failed to create prog_array '%s'\n", strerror(errno));
 
diff --git a/samples/bpf/tracex2_kern.c b/samples/bpf/tracex2_kern.c
index b32367c..09c1adc 100644
--- a/samples/bpf/tracex2_kern.c
+++ b/samples/bpf/tracex2_kern.c
@@ -70,7 +70,7 @@ struct hist_key {
 };
 
 struct bpf_map_def SEC("maps") my_hist_map = {
-	.type = BPF_MAP_TYPE_HASH,
+	.type = BPF_MAP_TYPE_PERCPU_HASH,
 	.key_size = sizeof(struct hist_key),
 	.value_size = sizeof(long),
 	.max_entries = 1024,
diff --git a/samples/bpf/tracex2_user.c b/samples/bpf/tracex2_user.c
index cd0241c..ab5b19e 100644
--- a/samples/bpf/tracex2_user.c
+++ b/samples/bpf/tracex2_user.c
@@ -37,6 +37,8 @@ struct hist_key {
 static void print_hist_for_pid(int fd, void *task)
 {
 	struct hist_key key = {}, next_key;
+	unsigned int nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
+	long values[nr_cpus];
 	char starstr[MAX_STARS];
 	long value;
 	long data[MAX_INDEX] = {};
@@ -49,7 +51,10 @@ static void print_hist_for_pid(int fd, void *task)
 			key = next_key;
 			continue;
 		}
-		bpf_lookup_elem(fd, &next_key, &value);
+		bpf_lookup_elem(fd, &next_key, values);
+		value = 0;
+		for (i = 0; i < nr_cpus; i++)
+			value += values[i];
 		ind = next_key.index;
 		data[ind] = value;
 		if (value && ind > max_ind)
diff --git a/samples/bpf/tracex3_kern.c b/samples/bpf/tracex3_kern.c
index bf337fb..9974c3d 100644
--- a/samples/bpf/tracex3_kern.c
+++ b/samples/bpf/tracex3_kern.c
@@ -20,7 +20,7 @@ struct bpf_map_def SEC("maps") my_map = {
 /* kprobe is NOT a stable ABI. If kernel internals change this bpf+kprobe
  * example will no longer be meaningful
  */
-SEC("kprobe/blk_mq_start_request")
+SEC("kprobe/blk_start_request")
 int bpf_prog1(struct pt_regs *ctx)
 {
 	long rq = PT_REGS_PARM1(ctx);
@@ -42,13 +42,13 @@ static unsigned int log2l(unsigned long long n)
 #define SLOTS 100
 
 struct bpf_map_def SEC("maps") lat_map = {
-	.type = BPF_MAP_TYPE_ARRAY,
+	.type = BPF_MAP_TYPE_PERCPU_ARRAY,
 	.key_size = sizeof(u32),
 	.value_size = sizeof(u64),
 	.max_entries = SLOTS,
 };
 
-SEC("kprobe/blk_update_request")
+SEC("kprobe/blk_account_io_completion")
 int bpf_prog2(struct pt_regs *ctx)
 {
 	long rq = PT_REGS_PARM1(ctx);
@@ -81,7 +81,7 @@ int bpf_prog2(struct pt_regs *ctx)
 
 	value = bpf_map_lookup_elem(&lat_map, &index);
 	if (value)
-		__sync_fetch_and_add((long *)value, 1);
+		*value += 1;
 
 	return 0;
 }
diff --git a/samples/bpf/tracex3_user.c b/samples/bpf/tracex3_user.c
index 0aaa933..48716f7 100644
--- a/samples/bpf/tracex3_user.c
+++ b/samples/bpf/tracex3_user.c
@@ -20,11 +20,13 @@
 
 static void clear_stats(int fd)
 {
+	unsigned int nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
+	__u64 values[nr_cpus];
 	__u32 key;
-	__u64 value = 0;
 
+	memset(values, 0, sizeof(values));
 	for (key = 0; key < SLOTS; key++)
-		bpf_update_elem(fd, &key, &value, BPF_ANY);
+		bpf_update_elem(fd, &key, values, BPF_ANY);
 }
 
 const char *color[] = {
@@ -75,15 +77,20 @@ static void print_banner(void)
 
 static void print_hist(int fd)
 {
-	__u32 key;
-	__u64 value;
-	__u64 cnt[SLOTS];
-	__u64 max_cnt = 0;
+	unsigned int nr_cpus = sysconf(_SC_NPROCESSORS_CONF);
 	__u64 total_events = 0;
+	long values[nr_cpus];
+	__u64 max_cnt = 0;
+	__u64 cnt[SLOTS];
+	__u64 value;
+	__u32 key;
+	int i;
 
 	for (key = 0; key < SLOTS; key++) {
+		bpf_lookup_elem(fd, &key, values);
 		value = 0;
-		bpf_lookup_elem(fd, &key, &value);
+		for (i = 0; i < nr_cpus; i++)
+			value += values[i];
 		cnt[key] = value;
 		total_events += value;
 		if (value > max_cnt)