Merge tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextgrafted

Pull networking updates from Jakub Kicinski:
 "Core:

   - Add dedicated kmem_cache for typical/small skb->head, avoid having
     to access struct page at kfree time, and improve memory use.

   - Introduce sysctl to set default RPS configuration for new netdevs.

   - Define Netlink protocol specification format which can be used to
     describe messages used by each family and auto-generate parsers.
     Add tools for generating kernel data structures and uAPI headers.

   - Expose all net/core sysctls inside netns.

   - Remove 4s sleep in netpoll if carrier is instantly detected on
     boot.

   - Add configurable limit of MDB entries per port, and port-vlan.

   - Continue populating drop reasons throughout the stack.

   - Retire a handful of legacy Qdiscs and classifiers.

  Protocols:

   - Support IPv4 big TCP (TSO frames larger than 64kB).

   - Add IP_LOCAL_PORT_RANGE socket option, to control local port range
     on socket by socket basis.

   - Track and report in procfs number of MPTCP sockets used.

   - Support mixing IPv4 and IPv6 flows in the in-kernel MPTCP path
     manager.

   - IPv6: don't check net.ipv6.route.max_size and rely on garbage
     collection to free memory (similarly to IPv4).

   - Support Penultimate Segment Pop (PSP) flavor in SRv6 (RFC8986).

   - ICMP: add per-rate limit counters.

   - Add support for user scanning requests in ieee802154.

   - Remove static WEP support.

   - Support minimal Wi-Fi 7 Extremely High Throughput (EHT) rate
     reporting.

   - WiFi 7 EHT channel puncturing support (client & AP).

  BPF:

   - Add a rbtree data structure following the "next-gen data structure"
     precedent set by recently added linked list, that is, by using
     kfunc + kptr instead of adding a new BPF map type.

   - Expose XDP hints via kfuncs with initial support for RX hash and
     timestamp metadata.

   - Add BPF_F_NO_TUNNEL_KEY extension to bpf_skb_set_tunnel_key to
     better support decap on GRE tunnel devices not operating in collect
     metadata.

   - Improve x86 JIT's codegen for PROBE_MEM runtime error checks.

   - Remove the need for trace_printk_lock for bpf_trace_printk and
     bpf_trace_vprintk helpers.

   - Extend libbpf's bpf_tracing.h support for tracing arguments of
     kprobes/uprobes and syscall as a special case.

   - Significantly reduce the search time for module symbols by
     livepatch and BPF.

   - Enable cpumasks to be used as kptrs, which is useful for tracing
     programs tracking which tasks end up running on which CPUs in
     different time intervals.

   - Add support for BPF trampoline on s390x and riscv64.

   - Add capability to export the XDP features supported by the NIC.

   - Add __bpf_kfunc tag for marking kernel functions as kfuncs.

   - Add cgroup.memory=nobpf kernel parameter option to disable BPF
     memory accounting for container environments.

  Netfilter:

   - Remove the CLUSTERIP target. It has been marked as obsolete for
     years, and we still have WARN splats wrt races of the out-of-band
     /proc interface installed by this target.

   - Add 'destroy' commands to nf_tables. They are identical to the
     existing 'delete' commands, but do not return an error if the
     referenced object (set, chain, rule...) did not exist.

  Driver API:

   - Improve cpumask_local_spread() locality to help NICs set the right
     IRQ affinity on AMD platforms.

   - Separate C22 and C45 MDIO bus transactions more clearly.

   - Introduce new DCB table to control DSCP rewrite on egress.

   - Support configuration of Physical Layer Collision Avoidance (PLCA)
     Reconciliation Sublayer (RS) (802.3cg-2019). Modern version of
     shared medium Ethernet.

   - Support for MAC Merge layer (IEEE 802.3-2018 clause 99). Allowing
     preemption of low priority frames by high priority frames.

   - Add support for controlling MACSec offload using netlink SET.

   - Rework devlink instance refcounts to allow registration and
     de-registration under the instance lock. Split the code into
     multiple files, drop some of the unnecessarily granular locks and
     factor out common parts of netlink operation handling.

   - Add TX frame aggregation parameters (for USB drivers).

   - Add a new attr TCA_EXT_WARN_MSG to report TC (offload) warning
     messages with notifications for debug.

   - Allow offloading of UDP NEW connections via act_ct.

   - Add support for per action HW stats in TC.

   - Support hardware miss to TC action (continue processing in SW from
     a specific point in the action chain).

   - Warn if old Wireless Extension user space interface is used with
     modern cfg80211/mac80211 drivers. Do not support Wireless
     Extensions for Wi-Fi 7 devices at all. Everyone should switch to
     using nl80211 interface instead.

   - Improve the CAN bit timing configuration. Use extack to return
     error messages directly to user space, update the SJW handling,
     including the definition of a new default value that will benefit
     CAN-FD controllers, by increasing their oscillator tolerance.

  New hardware / drivers:

   - Ethernet:
      - nVidia BlueField-3 support (control traffic driver)
      - Ethernet support for imx93 SoCs
      - Motorcomm yt8531 gigabit Ethernet PHY
      - onsemi NCN26000 10BASE-T1S PHY (with support for PLCA)
      - Microchip LAN8841 PHY (incl. cable diagnostics and PTP)
      - Amlogic gxl MDIO mux

   - WiFi:
      - RealTek RTL8188EU (rtl8xxxu)
      - Qualcomm Wi-Fi 7 devices (ath12k)

   - CAN:
      - Renesas R-Car V4H

  Drivers:

   - Bluetooth:
      - Set Per Platform Antenna Gain (PPAG) for Intel controllers.

   - Ethernet NICs:
      - Intel (1G, igc):
         - support TSN / Qbv / packet scheduling features of i226 model
      - Intel (100G, ice):
         - use GNSS subsystem instead of TTY
         - multi-buffer XDP support
         - extend support for GPIO pins to E823 devices
      - nVidia/Mellanox:
         - update the shared buffer configuration on PFC commands
         - implement PTP adjphase function for HW offset control
         - TC support for Geneve and GRE with VF tunnel offload
         - more efficient crypto key management method
         - multi-port eswitch support
      - Netronome/Corigine:
         - add DCB IEEE support
         - support IPsec offloading for NFP3800
      - Freescale/NXP (enetc):
         - support XDP_REDIRECT for XDP non-linear buffers
         - improve reconfig, avoid link flap and waiting for idle
         - support MAC Merge layer
      - Other NICs:
         - sfc/ef100: add basic devlink support for ef100
         - ionic: rx_push mode operation (writing descriptors via MMIO)
         - bnxt: use the auxiliary bus abstraction for RDMA
         - r8169: disable ASPM and reset bus in case of tx timeout
         - cpsw: support QSGMII mode for J721e CPSW9G
         - cpts: support pulse-per-second output
         - ngbe: add an mdio bus driver
         - usbnet: optimize usbnet_bh() by avoiding unnecessary queuing
         - r8152: handle devices with FW with NCM support
         - amd-xgbe: support 10Mbps, 2.5GbE speeds and rx-adaptation
         - virtio-net: support multi buffer XDP
         - virtio/vsock: replace virtio_vsock_pkt with sk_buff
         - tsnep: XDP support

   - Ethernet high-speed switches:
      - nVidia/Mellanox (mlxsw):
         - add support for latency TLV (in FW control messages)
      - Microchip (sparx5):
         - separate explicit and implicit traffic forwarding rules, make
           the implicit rules always active
         - add support for egress DSCP rewrite
         - IS0 VCAP support (Ingress Classification)
         - IS2 VCAP filters (protos, L3 addrs, L4 ports, flags, ToS
           etc.)
         - ES2 VCAP support (Egress Access Control)
         - support for Per-Stream Filtering and Policing (802.1Q,
           8.6.5.1)

   - Ethernet embedded switches:
      - Marvell (mv88e6xxx):
         - add MAB (port auth) offload support
         - enable PTP receive for mv88e6390
      - NXP (ocelot):
         - support MAC Merge layer
         - support for the the vsc7512 internal copper phys
      - Microchip:
         - lan9303: convert to PHYLINK
         - lan966x: support TC flower filter statistics
         - lan937x: PTP support for KSZ9563/KSZ8563 and LAN937x
         - lan937x: support Credit Based Shaper configuration
         - ksz9477: support Energy Efficient Ethernet
      - other:
         - qca8k: convert to regmap read/write API, use bulk operations
         - rswitch: Improve TX timestamp accuracy

   - Intel WiFi (iwlwifi):
      - EHT (Wi-Fi 7) rate reporting
      - STEP equalizer support: transfer some STEP (connection to radio
        on platforms with integrated wifi) related parameters from the
        BIOS to the firmware.

   - Qualcomm 802.11ax WiFi (ath11k):
      - IPQ5018 support
      - Fine Timing Measurement (FTM) responder role support
      - channel 177 support

   - MediaTek WiFi (mt76):
      - per-PHY LED support
      - mt7996: EHT (Wi-Fi 7) support
      - Wireless Ethernet Dispatch (WED) reset support
      - switch to using page pool allocator

   - RealTek WiFi (rtw89):
      - support new version of Bluetooth co-existance

   - Mobile:
      - rmnet: support TX aggregation"

* tag 'net-next-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1872 commits)
  page_pool: add a comment explaining the fragment counter usage
  net: ethtool: fix __ethtool_dev_mm_supported() implementation
  ethtool: pse-pd: Fix double word in comments
  xsk: add linux/vmalloc.h to xsk.c
  sefltests: netdevsim: wait for devlink instance after netns removal
  selftest: fib_tests: Always cleanup before exit
  net/mlx5e: Align IPsec ASO result memory to be as required by hardware
  net/mlx5e: TC, Set CT miss to the specific ct action instance
  net/mlx5e: Rename CHAIN_TO_REG to MAPPED_OBJ_TO_REG
  net/mlx5: Refactor tc miss handling to a single function
  net/mlx5: Kconfig: Make tc offload depend on tc skb extension
  net/sched: flower: Support hardware miss to tc action
  net/sched: flower: Move filter handle initialization earlier
  net/sched: cls_api: Support hardware miss to tc action
  net/sched: Rename user cookie and act cookie
  sfc: fix builds without CONFIG_RTC_LIB
  sfc: clean up some inconsistent indentings
  net/mlx4_en: Introduce flexible array to silence overflow warning
  net: lan966x: Fix possible deadlock inside PTP
  net/ulp: Remove redundant ->clone() test in inet_clone_ulp().
  ...

1 files changed, 559 insertions, 0 deletions

diff --git a/tools/perf/util/time-utils.c b/tools/perf/util/time-utils.c
new file mode 100644
index 000000000..302443921
--- /dev/null
+++ b/tools/perf/util/time-utils.c
@@ -0,0 +1,559 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <stdlib.h>
+#include <string.h>
+#include <linux/string.h>
+#include <sys/time.h>
+#include <linux/time64.h>
+#include <time.h>
+#include <errno.h>
+#include <inttypes.h>
+#include <math.h>
+#include <linux/ctype.h>
+
+#include "debug.h"
+#include "time-utils.h"
+#include "session.h"
+#include "evlist.h"
+
+int parse_nsec_time(const char *str, u64 *ptime)
+{
+	u64 time_sec, time_nsec;
+	char *end;
+
+	time_sec = strtoul(str, &end, 10);
+	if (*end != '.' && *end != '\0')
+		return -1;
+
+	if (*end == '.') {
+		int i;
+		char nsec_buf[10];
+
+		if (strlen(++end) > 9)
+			return -1;
+
+		strncpy(nsec_buf, end, 9);
+		nsec_buf[9] = '\0';
+
+		/* make it nsec precision */
+		for (i = strlen(nsec_buf); i < 9; i++)
+			nsec_buf[i] = '0';
+
+		time_nsec = strtoul(nsec_buf, &end, 10);
+		if (*end != '\0')
+			return -1;
+	} else
+		time_nsec = 0;
+
+	*ptime = time_sec * NSEC_PER_SEC + time_nsec;
+	return 0;
+}
+
+static int parse_timestr_sec_nsec(struct perf_time_interval *ptime,
+				  char *start_str, char *end_str)
+{
+	if (start_str && (*start_str != '\0') &&
+	    (parse_nsec_time(start_str, &ptime->start) != 0)) {
+		return -1;
+	}
+
+	if (end_str && (*end_str != '\0') &&
+	    (parse_nsec_time(end_str, &ptime->end) != 0)) {
+		return -1;
+	}
+
+	return 0;
+}
+
+static int split_start_end(char **start, char **end, const char *ostr, char ch)
+{
+	char *start_str, *end_str;
+	char *d, *str;
+
+	if (ostr == NULL || *ostr == '\0')
+		return 0;
+
+	/* copy original string because we need to modify it */
+	str = strdup(ostr);
+	if (str == NULL)
+		return -ENOMEM;
+
+	start_str = str;
+	d = strchr(start_str, ch);
+	if (d) {
+		*d = '\0';
+		++d;
+	}
+	end_str = d;
+
+	*start = start_str;
+	*end = end_str;
+
+	return 0;
+}
+
+int perf_time__parse_str(struct perf_time_interval *ptime, const char *ostr)
+{
+	char *start_str = NULL, *end_str;
+	int rc;
+
+	rc = split_start_end(&start_str, &end_str, ostr, ',');
+	if (rc || !start_str)
+		return rc;
+
+	ptime->start = 0;
+	ptime->end = 0;
+
+	rc = parse_timestr_sec_nsec(ptime, start_str, end_str);
+
+	free(start_str);
+
+	/* make sure end time is after start time if it was given */
+	if (rc == 0 && ptime->end && ptime->end < ptime->start)
+		return -EINVAL;
+
+	pr_debug("start time %" PRIu64 ", ", ptime->start);
+	pr_debug("end time %" PRIu64 "\n", ptime->end);
+
+	return rc;
+}
+
+static int perf_time__parse_strs(struct perf_time_interval *ptime,
+				 const char *ostr, int size)
+{
+	const char *cp;
+	char *str, *arg, *p;
+	int i, num = 0, rc = 0;
+
+	/* Count the commas */
+	for (cp = ostr; *cp; cp++)
+		num += !!(*cp == ',');
+
+	if (!num)
+		return -EINVAL;
+
+	BUG_ON(num > size);
+
+	str = strdup(ostr);
+	if (!str)
+		return -ENOMEM;
+
+	/* Split the string and parse each piece, except the last */
+	for (i = 0, p = str; i < num - 1; i++) {
+		arg = p;
+		/* Find next comma, there must be one */
+		p = skip_spaces(strchr(p, ',') + 1);
+		/* Skip the value, must not contain space or comma */
+		while (*p && !isspace(*p)) {
+			if (*p++ == ',') {
+				rc = -EINVAL;
+				goto out;
+			}
+		}
+		/* Split and parse */
+		if (*p)
+			*p++ = 0;
+		rc = perf_time__parse_str(ptime + i, arg);
+		if (rc < 0)
+			goto out;
+	}
+
+	/* Parse the last piece */
+	rc = perf_time__parse_str(ptime + i, p);
+	if (rc < 0)
+		goto out;
+
+	/* Check there is no overlap */
+	for (i = 0; i < num - 1; i++) {
+		if (ptime[i].end >= ptime[i + 1].start) {
+			rc = -EINVAL;
+			goto out;
+		}
+	}
+
+	rc = num;
+out:
+	free(str);
+
+	return rc;
+}
+
+static int parse_percent(double *pcnt, char *str)
+{
+	char *c, *endptr;
+	double d;
+
+	c = strchr(str, '%');
+	if (c)
+		*c = '\0';
+	else
+		return -1;
+
+	d = strtod(str, &endptr);
+	if (endptr != str + strlen(str))
+		return -1;
+
+	*pcnt = d / 100.0;
+	return 0;
+}
+
+static int set_percent_time(struct perf_time_interval *ptime, double start_pcnt,
+			    double end_pcnt, u64 start, u64 end)
+{
+	u64 total = end - start;
+
+	if (start_pcnt < 0.0 || start_pcnt > 1.0 ||
+	    end_pcnt < 0.0 || end_pcnt > 1.0) {
+		return -1;
+	}
+
+	ptime->start = start + round(start_pcnt * total);
+	ptime->end = start + round(end_pcnt * total);
+
+	if (ptime->end > ptime->start && ptime->end != end)
+		ptime->end -= 1;
+
+	return 0;
+}
+
+static int percent_slash_split(char *str, struct perf_time_interval *ptime,
+			       u64 start, u64 end)
+{
+	char *p, *end_str;
+	double pcnt, start_pcnt, end_pcnt;
+	int i;
+
+	/*
+	 * Example:
+	 * 10%/2: select the second 10% slice and the third 10% slice
+	 */
+
+	/* We can modify this string since the original one is copied */
+	p = strchr(str, '/');
+	if (!p)
+		return -1;
+
+	*p = '\0';
+	if (parse_percent(&pcnt, str) < 0)
+		return -1;
+
+	p++;
+	i = (int)strtol(p, &end_str, 10);
+	if (*end_str)
+		return -1;
+
+	if (pcnt <= 0.0)
+		return -1;
+
+	start_pcnt = pcnt * (i - 1);
+	end_pcnt = pcnt * i;
+
+	return set_percent_time(ptime, start_pcnt, end_pcnt, start, end);
+}
+
+static int percent_dash_split(char *str, struct perf_time_interval *ptime,
+			      u64 start, u64 end)
+{
+	char *start_str = NULL, *end_str;
+	double start_pcnt, end_pcnt;
+	int ret;
+
+	/*
+	 * Example: 0%-10%
+	 */
+
+	ret = split_start_end(&start_str, &end_str, str, '-');
+	if (ret || !start_str)
+		return ret;
+
+	if ((parse_percent(&start_pcnt, start_str) != 0) ||
+	    (parse_percent(&end_pcnt, end_str) != 0)) {
+		free(start_str);
+		return -1;
+	}
+
+	free(start_str);
+
+	return set_percent_time(ptime, start_pcnt, end_pcnt, start, end);
+}
+
+typedef int (*time_pecent_split)(char *, struct perf_time_interval *,
+				 u64 start, u64 end);
+
+static int percent_comma_split(struct perf_time_interval *ptime_buf, int num,
+			       const char *ostr, u64 start, u64 end,
+			       time_pecent_split func)
+{
+	char *str, *p1, *p2;
+	int len, ret, i = 0;
+
+	str = strdup(ostr);
+	if (str == NULL)
+		return -ENOMEM;
+
+	len = strlen(str);
+	p1 = str;
+
+	while (p1 < str + len) {
+		if (i >= num) {
+			free(str);
+			return -1;
+		}
+
+		p2 = strchr(p1, ',');
+		if (p2)
+			*p2 = '\0';
+
+		ret = (func)(p1, &ptime_buf[i], start, end);
+		if (ret < 0) {
+			free(str);
+			return -1;
+		}
+
+		pr_debug("start time %d: %" PRIu64 ", ", i, ptime_buf[i].start);
+		pr_debug("end time %d: %" PRIu64 "\n", i, ptime_buf[i].end);
+
+		i++;
+
+		if (p2)
+			p1 = p2 + 1;
+		else
+			break;
+	}
+
+	free(str);
+	return i;
+}
+
+static int one_percent_convert(struct perf_time_interval *ptime_buf,
+			       const char *ostr, u64 start, u64 end, char *c)
+{
+	char *str;
+	int len = strlen(ostr), ret;
+
+	/*
+	 * c points to '%'.
+	 * '%' should be the last character
+	 */
+	if (ostr + len - 1 != c)
+		return -1;
+
+	/*
+	 * Construct a string like "xx%/1"
+	 */
+	str = malloc(len + 3);
+	if (str == NULL)
+		return -ENOMEM;
+
+	memcpy(str, ostr, len);
+	strcpy(str + len, "/1");
+
+	ret = percent_slash_split(str, ptime_buf, start, end);
+	if (ret == 0)
+		ret = 1;
+
+	free(str);
+	return ret;
+}
+
+int perf_time__percent_parse_str(struct perf_time_interval *ptime_buf, int num,
+				 const char *ostr, u64 start, u64 end)
+{
+	char *c;
+
+	/*
+	 * ostr example:
+	 * 10%/2,10%/3: select the second 10% slice and the third 10% slice
+	 * 0%-10%,30%-40%: multiple time range
+	 * 50%: just one percent
+	 */
+
+	memset(ptime_buf, 0, sizeof(*ptime_buf) * num);
+
+	c = strchr(ostr, '/');
+	if (c) {
+		return percent_comma_split(ptime_buf, num, ostr, start,
+					   end, percent_slash_split);
+	}
+
+	c = strchr(ostr, '-');
+	if (c) {
+		return percent_comma_split(ptime_buf, num, ostr, start,
+					   end, percent_dash_split);
+	}
+
+	c = strchr(ostr, '%');
+	if (c)
+		return one_percent_convert(ptime_buf, ostr, start, end, c);
+
+	return -1;
+}
+
+struct perf_time_interval *perf_time__range_alloc(const char *ostr, int *size)
+{
+	const char *p1, *p2;
+	int i = 1;
+	struct perf_time_interval *ptime;
+
+	/*
+	 * At least allocate one time range.
+	 */
+	if (!ostr)
+		goto alloc;
+
+	p1 = ostr;
+	while (p1 < ostr + strlen(ostr)) {
+		p2 = strchr(p1, ',');
+		if (!p2)
+			break;
+
+		p1 = p2 + 1;
+		i++;
+	}
+
+alloc:
+	*size = i;
+	ptime = calloc(i, sizeof(*ptime));
+	return ptime;
+}
+
+bool perf_time__skip_sample(struct perf_time_interval *ptime, u64 timestamp)
+{
+	/* if time is not set don't drop sample */
+	if (timestamp == 0)
+		return false;
+
+	/* otherwise compare sample time to time window */
+	if ((ptime->start && timestamp < ptime->start) ||
+	    (ptime->end && timestamp > ptime->end)) {
+		return true;
+	}
+
+	return false;
+}
+
+bool perf_time__ranges_skip_sample(struct perf_time_interval *ptime_buf,
+				   int num, u64 timestamp)
+{
+	struct perf_time_interval *ptime;
+	int i;
+
+	if ((!ptime_buf) || (timestamp == 0) || (num == 0))
+		return false;
+
+	if (num == 1)
+		return perf_time__skip_sample(&ptime_buf[0], timestamp);
+
+	/*
+	 * start/end of multiple time ranges must be valid.
+	 */
+	for (i = 0; i < num; i++) {
+		ptime = &ptime_buf[i];
+
+		if (timestamp >= ptime->start &&
+		    (timestamp <= ptime->end || !ptime->end)) {
+			return false;
+		}
+	}
+
+	return true;
+}
+
+int perf_time__parse_for_ranges_reltime(const char *time_str,
+				struct perf_session *session,
+				struct perf_time_interval **ranges,
+				int *range_size, int *range_num,
+				bool reltime)
+{
+	bool has_percent = strchr(time_str, '%');
+	struct perf_time_interval *ptime_range;
+	int size, num, ret = -EINVAL;
+
+	ptime_range = perf_time__range_alloc(time_str, &size);
+	if (!ptime_range)
+		return -ENOMEM;
+
+	if (has_percent || reltime) {
+		if (session->evlist->first_sample_time == 0 &&
+		    session->evlist->last_sample_time == 0) {
+			pr_err("HINT: no first/last sample time found in perf data.\n"
+			       "Please use latest perf binary to execute 'perf record'\n"
+			       "(if '--buildid-all' is enabled, please set '--timestamp-boundary').\n");
+			goto error;
+		}
+	}
+
+	if (has_percent) {
+		num = perf_time__percent_parse_str(
+				ptime_range, size,
+				time_str,
+				session->evlist->first_sample_time,
+				session->evlist->last_sample_time);
+	} else {
+		num = perf_time__parse_strs(ptime_range, time_str, size);
+	}
+
+	if (num < 0)
+		goto error_invalid;
+
+	if (reltime) {
+		int i;
+
+		for (i = 0; i < num; i++) {
+			ptime_range[i].start += session->evlist->first_sample_time;
+			ptime_range[i].end += session->evlist->first_sample_time;
+		}
+	}
+
+	*range_size = size;
+	*range_num = num;
+	*ranges = ptime_range;
+	return 0;
+
+error_invalid:
+	pr_err("Invalid time string\n");
+error:
+	free(ptime_range);
+	return ret;
+}
+
+int perf_time__parse_for_ranges(const char *time_str,
+				struct perf_session *session,
+				struct perf_time_interval **ranges,
+				int *range_size, int *range_num)
+{
+	return perf_time__parse_for_ranges_reltime(time_str, session, ranges,
+					range_size, range_num, false);
+}
+
+int timestamp__scnprintf_usec(u64 timestamp, char *buf, size_t sz)
+{
+	u64  sec = timestamp / NSEC_PER_SEC;
+	u64 usec = (timestamp % NSEC_PER_SEC) / NSEC_PER_USEC;
+
+	return scnprintf(buf, sz, "%"PRIu64".%06"PRIu64, sec, usec);
+}
+
+int timestamp__scnprintf_nsec(u64 timestamp, char *buf, size_t sz)
+{
+	u64 sec  = timestamp / NSEC_PER_SEC,
+	    nsec = timestamp % NSEC_PER_SEC;
+
+	return scnprintf(buf, sz, "%" PRIu64 ".%09" PRIu64, sec, nsec);
+}
+
+int fetch_current_timestamp(char *buf, size_t sz)
+{
+	struct timeval tv;
+	struct tm tm;
+	char dt[32];
+
+	if (gettimeofday(&tv, NULL) || !localtime_r(&tv.tv_sec, &tm))
+		return -1;
+
+	if (!strftime(dt, sizeof(dt), "%Y%m%d%H%M%S", &tm))
+		return -1;
+
+	scnprintf(buf, sz, "%s%02u", dt, (unsigned)tv.tv_usec / 10000);
+
+	return 0;
+}