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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 /tools/perf/Documentation/perf-dlfilter.txt
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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(). ...
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+perf-dlfilter(1)
+================
+
+NAME
+----
+perf-dlfilter - Filter sample events using a dynamically loaded shared
+object file
+
+SYNOPSIS
+--------
+[verse]
+'perf script' [--dlfilter file.so ] [ --dlarg arg ]...
+
+DESCRIPTION
+-----------
+
+This option is used to process data through a custom filter provided by a
+dynamically loaded shared object file. Arguments can be passed using --dlarg
+and retrieved using perf_dlfilter_fns.args().
+
+If 'file.so' does not contain "/", then it will be found either in the current
+directory, or perf tools exec path which is ~/libexec/perf-core/dlfilters for
+a local build and install (refer perf --exec-path), or the dynamic linker
+paths.
+
+API
+---
+
+The API for filtering consists of the following:
+
+[source,c]
+----
+#include <perf/perf_dlfilter.h>
+
+struct perf_dlfilter_fns perf_dlfilter_fns;
+
+int start(void **data, void *ctx);
+int stop(void *data, void *ctx);
+int filter_event(void *data, const struct perf_dlfilter_sample *sample, void *ctx);
+int filter_event_early(void *data, const struct perf_dlfilter_sample *sample, void *ctx);
+const char *filter_description(const char **long_description);
+----
+
+If implemented, 'start' will be called at the beginning, before any
+calls to 'filter_event' or 'filter_event_early'. Return 0 to indicate success,
+or return a negative error code. '*data' can be assigned for use by other
+functions. 'ctx' is needed for calls to perf_dlfilter_fns, but most
+perf_dlfilter_fns are not valid when called from 'start'.
+
+If implemented, 'stop' will be called at the end, after any calls to
+'filter_event' or 'filter_event_early'. Return 0 to indicate success, or
+return a negative error code. 'data' is set by 'start'. 'ctx' is needed
+for calls to perf_dlfilter_fns, but most perf_dlfilter_fns are not valid
+when called from 'stop'.
+
+If implemented, 'filter_event' will be called for each sample event.
+Return 0 to keep the sample event, 1 to filter it out, or return a negative
+error code. 'data' is set by 'start'. 'ctx' is needed for calls to
+'perf_dlfilter_fns'.
+
+'filter_event_early' is the same as 'filter_event' except it is called before
+internal filtering.
+
+If implemented, 'filter_description' should return a one-line description
+of the filter, and optionally a longer description.
+
+The perf_dlfilter_sample structure
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+'filter_event' and 'filter_event_early' are passed a perf_dlfilter_sample
+structure, which contains the following fields:
+[source,c]
+----
+/*
+ * perf sample event information (as per perf script and <linux/perf_event.h>)
+ */
+struct perf_dlfilter_sample {
+ __u32 size; /* Size of this structure (for compatibility checking) */
+ __u16 ins_lat; /* Refer PERF_SAMPLE_WEIGHT_TYPE in <linux/perf_event.h> */
+ __u16 p_stage_cyc; /* Refer PERF_SAMPLE_WEIGHT_TYPE in <linux/perf_event.h> */
+ __u64 ip;
+ __s32 pid;
+ __s32 tid;
+ __u64 time;
+ __u64 addr;
+ __u64 id;
+ __u64 stream_id;
+ __u64 period;
+ __u64 weight; /* Refer PERF_SAMPLE_WEIGHT_TYPE in <linux/perf_event.h> */
+ __u64 transaction; /* Refer PERF_SAMPLE_TRANSACTION in <linux/perf_event.h> */
+ __u64 insn_cnt; /* For instructions-per-cycle (IPC) */
+ __u64 cyc_cnt; /* For instructions-per-cycle (IPC) */
+ __s32 cpu;
+ __u32 flags; /* Refer PERF_DLFILTER_FLAG_* above */
+ __u64 data_src; /* Refer PERF_SAMPLE_DATA_SRC in <linux/perf_event.h> */
+ __u64 phys_addr; /* Refer PERF_SAMPLE_PHYS_ADDR in <linux/perf_event.h> */
+ __u64 data_page_size; /* Refer PERF_SAMPLE_DATA_PAGE_SIZE in <linux/perf_event.h> */
+ __u64 code_page_size; /* Refer PERF_SAMPLE_CODE_PAGE_SIZE in <linux/perf_event.h> */
+ __u64 cgroup; /* Refer PERF_SAMPLE_CGROUP in <linux/perf_event.h> */
+ __u8 cpumode; /* Refer CPUMODE_MASK etc in <linux/perf_event.h> */
+ __u8 addr_correlates_sym; /* True => resolve_addr() can be called */
+ __u16 misc; /* Refer perf_event_header in <linux/perf_event.h> */
+ __u32 raw_size; /* Refer PERF_SAMPLE_RAW in <linux/perf_event.h> */
+ const void *raw_data; /* Refer PERF_SAMPLE_RAW in <linux/perf_event.h> */
+ __u64 brstack_nr; /* Number of brstack entries */
+ const struct perf_branch_entry *brstack; /* Refer <linux/perf_event.h> */
+ __u64 raw_callchain_nr; /* Number of raw_callchain entries */
+ const __u64 *raw_callchain; /* Refer <linux/perf_event.h> */
+ const char *event;
+ __s32 machine_pid;
+ __s32 vcpu;
+};
+----
+
+Note: 'machine_pid' and 'vcpu' are not original members, but were added together later.
+'size' can be used to determine their presence at run time.
+PERF_DLFILTER_HAS_MACHINE_PID will be defined if they are present at compile time.
+For example:
+[source,c]
+----
+#include <perf/perf_dlfilter.h>
+#include <stddef.h>
+#include <stdbool.h>
+
+static inline bool have_machine_pid(const struct perf_dlfilter_sample *sample)
+{
+#ifdef PERF_DLFILTER_HAS_MACHINE_PID
+ return sample->size >= offsetof(struct perf_dlfilter_sample, vcpu) + sizeof(sample->vcpu);
+#else
+ return false;
+#endif
+}
+----
+
+The perf_dlfilter_fns structure
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+The 'perf_dlfilter_fns' structure is populated with function pointers when the
+file is loaded. The functions can be called by 'filter_event' or
+'filter_event_early'.
+
+[source,c]
+----
+struct perf_dlfilter_fns {
+ const struct perf_dlfilter_al *(*resolve_ip)(void *ctx);
+ const struct perf_dlfilter_al *(*resolve_addr)(void *ctx);
+ char **(*args)(void *ctx, int *dlargc);
+ __s32 (*resolve_address)(void *ctx, __u64 address, struct perf_dlfilter_al *al);
+ const __u8 *(*insn)(void *ctx, __u32 *length);
+ const char *(*srcline)(void *ctx, __u32 *line_number);
+ struct perf_event_attr *(*attr)(void *ctx);
+ __s32 (*object_code)(void *ctx, __u64 ip, void *buf, __u32 len);
+ void *(*reserved[120])(void *);
+};
+----
+
+'resolve_ip' returns information about ip.
+
+'resolve_addr' returns information about addr (if addr_correlates_sym).
+
+'args' returns arguments from --dlarg options.
+
+'resolve_address' provides information about 'address'. al->size must be set
+before calling. Returns 0 on success, -1 otherwise.
+
+'insn' returns instruction bytes and length.
+
+'srcline' return source file name and line number.
+
+'attr' returns perf_event_attr, refer <linux/perf_event.h>.
+
+'object_code' reads object code and returns the number of bytes read.
+
+The perf_dlfilter_al structure
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+The 'perf_dlfilter_al' structure contains information about an address.
+
+[source,c]
+----
+/*
+ * Address location (as per perf script)
+ */
+struct perf_dlfilter_al {
+ __u32 size; /* Size of this structure (for compatibility checking) */
+ __u32 symoff;
+ const char *sym;
+ __u64 addr; /* Mapped address (from dso) */
+ __u64 sym_start;
+ __u64 sym_end;
+ const char *dso;
+ __u8 sym_binding; /* STB_LOCAL, STB_GLOBAL or STB_WEAK, refer <elf.h> */
+ __u8 is_64_bit; /* Only valid if dso is not NULL */
+ __u8 is_kernel_ip; /* True if in kernel space */
+ __u32 buildid_size;
+ __u8 *buildid;
+ /* Below members are only populated by resolve_ip() */
+ __u8 filtered; /* true if this sample event will be filtered out */
+ const char *comm;
+};
+----
+
+perf_dlfilter_sample flags
+~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+The 'flags' member of 'perf_dlfilter_sample' corresponds with the flags field
+of perf script. The bits of the flags are as follows:
+
+[source,c]
+----
+/* Definitions for perf_dlfilter_sample flags */
+enum {
+ PERF_DLFILTER_FLAG_BRANCH = 1ULL << 0,
+ PERF_DLFILTER_FLAG_CALL = 1ULL << 1,
+ PERF_DLFILTER_FLAG_RETURN = 1ULL << 2,
+ PERF_DLFILTER_FLAG_CONDITIONAL = 1ULL << 3,
+ PERF_DLFILTER_FLAG_SYSCALLRET = 1ULL << 4,
+ PERF_DLFILTER_FLAG_ASYNC = 1ULL << 5,
+ PERF_DLFILTER_FLAG_INTERRUPT = 1ULL << 6,
+ PERF_DLFILTER_FLAG_TX_ABORT = 1ULL << 7,
+ PERF_DLFILTER_FLAG_TRACE_BEGIN = 1ULL << 8,
+ PERF_DLFILTER_FLAG_TRACE_END = 1ULL << 9,
+ PERF_DLFILTER_FLAG_IN_TX = 1ULL << 10,
+ PERF_DLFILTER_FLAG_VMENTRY = 1ULL << 11,
+ PERF_DLFILTER_FLAG_VMEXIT = 1ULL << 12,
+};
+----
+
+EXAMPLE
+-------
+
+Filter out everything except branches from "foo" to "bar":
+
+[source,c]
+----
+#include <perf/perf_dlfilter.h>
+#include <string.h>
+
+struct perf_dlfilter_fns perf_dlfilter_fns;
+
+int filter_event(void *data, const struct perf_dlfilter_sample *sample, void *ctx)
+{
+ const struct perf_dlfilter_al *al;
+ const struct perf_dlfilter_al *addr_al;
+
+ if (!sample->ip || !sample->addr_correlates_sym)
+ return 1;
+
+ al = perf_dlfilter_fns.resolve_ip(ctx);
+ if (!al || !al->sym || strcmp(al->sym, "foo"))
+ return 1;
+
+ addr_al = perf_dlfilter_fns.resolve_addr(ctx);
+ if (!addr_al || !addr_al->sym || strcmp(addr_al->sym, "bar"))
+ return 1;
+
+ return 0;
+}
+----
+
+To build the shared object, assuming perf has been installed for the local user
+i.e. perf_dlfilter.h is in ~/include/perf :
+
+ gcc -c -I ~/include -fpic dlfilter-example.c
+ gcc -shared -o dlfilter-example.so dlfilter-example.o
+
+To use the filter with perf script:
+
+ perf script --dlfilter dlfilter-example.so
+
+NOTES
+-----
+
+The dlfilter .so file will be dependent on shared libraries. If those change,
+it may be necessary to rebuild the .so. Also there may be unexpected results
+if the .so uses different versions of the shared libraries that perf uses.
+Versions can be checked using the ldd command.
+
+SEE ALSO
+--------
+linkperf:perf-script[1]