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authorLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
committerLibravatar Linus Torvalds <torvalds@linux-foundation.org>2023-02-21 18:24:12 -0800
commit5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch)
treecc5c2d0a898769fd59549594fedb3ee6f84e59a0 /init/calibrate.c
downloadlinux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz
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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(). ...
Diffstat (limited to 'init/calibrate.c')
-rw-r--r--init/calibrate.c316
1 files changed, 316 insertions, 0 deletions
diff --git a/init/calibrate.c b/init/calibrate.c
new file mode 100644
index 000000000..f3831272f
--- /dev/null
+++ b/init/calibrate.c
@@ -0,0 +1,316 @@
+// SPDX-License-Identifier: GPL-2.0
+/* calibrate.c: default delay calibration
+ *
+ * Excised from init/main.c
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ */
+
+#include <linux/jiffies.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/timex.h>
+#include <linux/smp.h>
+#include <linux/percpu.h>
+
+unsigned long lpj_fine;
+unsigned long preset_lpj;
+static int __init lpj_setup(char *str)
+{
+ preset_lpj = simple_strtoul(str,NULL,0);
+ return 1;
+}
+
+__setup("lpj=", lpj_setup);
+
+#ifdef ARCH_HAS_READ_CURRENT_TIMER
+
+/* This routine uses the read_current_timer() routine and gets the
+ * loops per jiffy directly, instead of guessing it using delay().
+ * Also, this code tries to handle non-maskable asynchronous events
+ * (like SMIs)
+ */
+#define DELAY_CALIBRATION_TICKS ((HZ < 100) ? 1 : (HZ/100))
+#define MAX_DIRECT_CALIBRATION_RETRIES 5
+
+static unsigned long calibrate_delay_direct(void)
+{
+ unsigned long pre_start, start, post_start;
+ unsigned long pre_end, end, post_end;
+ unsigned long start_jiffies;
+ unsigned long timer_rate_min, timer_rate_max;
+ unsigned long good_timer_sum = 0;
+ unsigned long good_timer_count = 0;
+ unsigned long measured_times[MAX_DIRECT_CALIBRATION_RETRIES];
+ int max = -1; /* index of measured_times with max/min values or not set */
+ int min = -1;
+ int i;
+
+ if (read_current_timer(&pre_start) < 0 )
+ return 0;
+
+ /*
+ * A simple loop like
+ * while ( jiffies < start_jiffies+1)
+ * start = read_current_timer();
+ * will not do. As we don't really know whether jiffy switch
+ * happened first or timer_value was read first. And some asynchronous
+ * event can happen between these two events introducing errors in lpj.
+ *
+ * So, we do
+ * 1. pre_start <- When we are sure that jiffy switch hasn't happened
+ * 2. check jiffy switch
+ * 3. start <- timer value before or after jiffy switch
+ * 4. post_start <- When we are sure that jiffy switch has happened
+ *
+ * Note, we don't know anything about order of 2 and 3.
+ * Now, by looking at post_start and pre_start difference, we can
+ * check whether any asynchronous event happened or not
+ */
+
+ for (i = 0; i < MAX_DIRECT_CALIBRATION_RETRIES; i++) {
+ pre_start = 0;
+ read_current_timer(&start);
+ start_jiffies = jiffies;
+ while (time_before_eq(jiffies, start_jiffies + 1)) {
+ pre_start = start;
+ read_current_timer(&start);
+ }
+ read_current_timer(&post_start);
+
+ pre_end = 0;
+ end = post_start;
+ while (time_before_eq(jiffies, start_jiffies + 1 +
+ DELAY_CALIBRATION_TICKS)) {
+ pre_end = end;
+ read_current_timer(&end);
+ }
+ read_current_timer(&post_end);
+
+ timer_rate_max = (post_end - pre_start) /
+ DELAY_CALIBRATION_TICKS;
+ timer_rate_min = (pre_end - post_start) /
+ DELAY_CALIBRATION_TICKS;
+
+ /*
+ * If the upper limit and lower limit of the timer_rate is
+ * >= 12.5% apart, redo calibration.
+ */
+ if (start >= post_end)
+ printk(KERN_NOTICE "calibrate_delay_direct() ignoring "
+ "timer_rate as we had a TSC wrap around"
+ " start=%lu >=post_end=%lu\n",
+ start, post_end);
+ if (start < post_end && pre_start != 0 && pre_end != 0 &&
+ (timer_rate_max - timer_rate_min) < (timer_rate_max >> 3)) {
+ good_timer_count++;
+ good_timer_sum += timer_rate_max;
+ measured_times[i] = timer_rate_max;
+ if (max < 0 || timer_rate_max > measured_times[max])
+ max = i;
+ if (min < 0 || timer_rate_max < measured_times[min])
+ min = i;
+ } else
+ measured_times[i] = 0;
+
+ }
+
+ /*
+ * Find the maximum & minimum - if they differ too much throw out the
+ * one with the largest difference from the mean and try again...
+ */
+ while (good_timer_count > 1) {
+ unsigned long estimate;
+ unsigned long maxdiff;
+
+ /* compute the estimate */
+ estimate = (good_timer_sum/good_timer_count);
+ maxdiff = estimate >> 3;
+
+ /* if range is within 12% let's take it */
+ if ((measured_times[max] - measured_times[min]) < maxdiff)
+ return estimate;
+
+ /* ok - drop the worse value and try again... */
+ good_timer_sum = 0;
+ good_timer_count = 0;
+ if ((measured_times[max] - estimate) <
+ (estimate - measured_times[min])) {
+ printk(KERN_NOTICE "calibrate_delay_direct() dropping "
+ "min bogoMips estimate %d = %lu\n",
+ min, measured_times[min]);
+ measured_times[min] = 0;
+ min = max;
+ } else {
+ printk(KERN_NOTICE "calibrate_delay_direct() dropping "
+ "max bogoMips estimate %d = %lu\n",
+ max, measured_times[max]);
+ measured_times[max] = 0;
+ max = min;
+ }
+
+ for (i = 0; i < MAX_DIRECT_CALIBRATION_RETRIES; i++) {
+ if (measured_times[i] == 0)
+ continue;
+ good_timer_count++;
+ good_timer_sum += measured_times[i];
+ if (measured_times[i] < measured_times[min])
+ min = i;
+ if (measured_times[i] > measured_times[max])
+ max = i;
+ }
+
+ }
+
+ printk(KERN_NOTICE "calibrate_delay_direct() failed to get a good "
+ "estimate for loops_per_jiffy.\nProbably due to long platform "
+ "interrupts. Consider using \"lpj=\" boot option.\n");
+ return 0;
+}
+#else
+static unsigned long calibrate_delay_direct(void)
+{
+ return 0;
+}
+#endif
+
+/*
+ * This is the number of bits of precision for the loops_per_jiffy. Each
+ * time we refine our estimate after the first takes 1.5/HZ seconds, so try
+ * to start with a good estimate.
+ * For the boot cpu we can skip the delay calibration and assign it a value
+ * calculated based on the timer frequency.
+ * For the rest of the CPUs we cannot assume that the timer frequency is same as
+ * the cpu frequency, hence do the calibration for those.
+ */
+#define LPS_PREC 8
+
+static unsigned long calibrate_delay_converge(void)
+{
+ /* First stage - slowly accelerate to find initial bounds */
+ unsigned long lpj, lpj_base, ticks, loopadd, loopadd_base, chop_limit;
+ int trials = 0, band = 0, trial_in_band = 0;
+
+ lpj = (1<<12);
+
+ /* wait for "start of" clock tick */
+ ticks = jiffies;
+ while (ticks == jiffies)
+ ; /* nothing */
+ /* Go .. */
+ ticks = jiffies;
+ do {
+ if (++trial_in_band == (1<<band)) {
+ ++band;
+ trial_in_band = 0;
+ }
+ __delay(lpj * band);
+ trials += band;
+ } while (ticks == jiffies);
+ /*
+ * We overshot, so retreat to a clear underestimate. Then estimate
+ * the largest likely undershoot. This defines our chop bounds.
+ */
+ trials -= band;
+ loopadd_base = lpj * band;
+ lpj_base = lpj * trials;
+
+recalibrate:
+ lpj = lpj_base;
+ loopadd = loopadd_base;
+
+ /*
+ * Do a binary approximation to get lpj set to
+ * equal one clock (up to LPS_PREC bits)
+ */
+ chop_limit = lpj >> LPS_PREC;
+ while (loopadd > chop_limit) {
+ lpj += loopadd;
+ ticks = jiffies;
+ while (ticks == jiffies)
+ ; /* nothing */
+ ticks = jiffies;
+ __delay(lpj);
+ if (jiffies != ticks) /* longer than 1 tick */
+ lpj -= loopadd;
+ loopadd >>= 1;
+ }
+ /*
+ * If we incremented every single time possible, presume we've
+ * massively underestimated initially, and retry with a higher
+ * start, and larger range. (Only seen on x86_64, due to SMIs)
+ */
+ if (lpj + loopadd * 2 == lpj_base + loopadd_base * 2) {
+ lpj_base = lpj;
+ loopadd_base <<= 2;
+ goto recalibrate;
+ }
+
+ return lpj;
+}
+
+static DEFINE_PER_CPU(unsigned long, cpu_loops_per_jiffy) = { 0 };
+
+/*
+ * Check if cpu calibration delay is already known. For example,
+ * some processors with multi-core sockets may have all cores
+ * with the same calibration delay.
+ *
+ * Architectures should override this function if a faster calibration
+ * method is available.
+ */
+unsigned long __attribute__((weak)) calibrate_delay_is_known(void)
+{
+ return 0;
+}
+
+/*
+ * Indicate the cpu delay calibration is done. This can be used by
+ * architectures to stop accepting delay timer registrations after this point.
+ */
+
+void __attribute__((weak)) calibration_delay_done(void)
+{
+}
+
+void calibrate_delay(void)
+{
+ unsigned long lpj;
+ static bool printed;
+ int this_cpu = smp_processor_id();
+
+ if (per_cpu(cpu_loops_per_jiffy, this_cpu)) {
+ lpj = per_cpu(cpu_loops_per_jiffy, this_cpu);
+ if (!printed)
+ pr_info("Calibrating delay loop (skipped) "
+ "already calibrated this CPU");
+ } else if (preset_lpj) {
+ lpj = preset_lpj;
+ if (!printed)
+ pr_info("Calibrating delay loop (skipped) "
+ "preset value.. ");
+ } else if ((!printed) && lpj_fine) {
+ lpj = lpj_fine;
+ pr_info("Calibrating delay loop (skipped), "
+ "value calculated using timer frequency.. ");
+ } else if ((lpj = calibrate_delay_is_known())) {
+ ;
+ } else if ((lpj = calibrate_delay_direct()) != 0) {
+ if (!printed)
+ pr_info("Calibrating delay using timer "
+ "specific routine.. ");
+ } else {
+ if (!printed)
+ pr_info("Calibrating delay loop... ");
+ lpj = calibrate_delay_converge();
+ }
+ per_cpu(cpu_loops_per_jiffy, this_cpu) = lpj;
+ if (!printed)
+ pr_cont("%lu.%02lu BogoMIPS (lpj=%lu)\n",
+ lpj/(500000/HZ),
+ (lpj/(5000/HZ)) % 100, lpj);
+
+ loops_per_jiffy = lpj;
+ printed = true;
+
+ calibration_delay_done();
+}