diff options
author | 2023-02-21 18:24:12 -0800 | |
---|---|---|
committer | 2023-02-21 18:24:12 -0800 | |
commit | 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch) | |
tree | cc5c2d0a898769fd59549594fedb3ee6f84e59a0 /arch/x86/events/amd/brs.c | |
download | linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.tar.gz linux-5b7c4cabbb65f5c469464da6c5f614cbd7f730f2.zip |
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 'arch/x86/events/amd/brs.c')
-rw-r--r-- | arch/x86/events/amd/brs.c | 431 |
1 files changed, 431 insertions, 0 deletions
diff --git a/arch/x86/events/amd/brs.c b/arch/x86/events/amd/brs.c new file mode 100644 index 000000000..ed3087192 --- /dev/null +++ b/arch/x86/events/amd/brs.c @@ -0,0 +1,431 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Implement support for AMD Fam19h Branch Sampling feature + * Based on specifications published in AMD PPR Fam19 Model 01 + * + * Copyright 2021 Google LLC + * Contributed by Stephane Eranian <eranian@google.com> + */ +#include <linux/kernel.h> +#include <linux/jump_label.h> +#include <asm/msr.h> +#include <asm/cpufeature.h> + +#include "../perf_event.h" + +#define BRS_POISON 0xFFFFFFFFFFFFFFFEULL /* mark limit of valid entries */ + +/* Debug Extension Configuration register layout */ +union amd_debug_extn_cfg { + __u64 val; + struct { + __u64 rsvd0:2, /* reserved */ + brsmen:1, /* branch sample enable */ + rsvd4_3:2,/* reserved - must be 0x3 */ + vb:1, /* valid branches recorded */ + rsvd2:10, /* reserved */ + msroff:4, /* index of next entry to write */ + rsvd3:4, /* reserved */ + pmc:3, /* #PMC holding the sampling event */ + rsvd4:37; /* reserved */ + }; +}; + +static inline unsigned int brs_from(int idx) +{ + return MSR_AMD_SAMP_BR_FROM + 2 * idx; +} + +static inline unsigned int brs_to(int idx) +{ + return MSR_AMD_SAMP_BR_FROM + 2 * idx + 1; +} + +static __always_inline void set_debug_extn_cfg(u64 val) +{ + /* bits[4:3] must always be set to 11b */ + __wrmsr(MSR_AMD_DBG_EXTN_CFG, val | 3ULL << 3, val >> 32); +} + +static __always_inline u64 get_debug_extn_cfg(void) +{ + return __rdmsr(MSR_AMD_DBG_EXTN_CFG); +} + +static bool __init amd_brs_detect(void) +{ + if (!cpu_feature_enabled(X86_FEATURE_BRS)) + return false; + + switch (boot_cpu_data.x86) { + case 0x19: /* AMD Fam19h (Zen3) */ + x86_pmu.lbr_nr = 16; + + /* No hardware filtering supported */ + x86_pmu.lbr_sel_map = NULL; + x86_pmu.lbr_sel_mask = 0; + break; + default: + return false; + } + + return true; +} + +/* + * Current BRS implementation does not support branch type or privilege level + * filtering. Therefore, this function simply enforces these limitations. No need for + * a br_sel_map. Software filtering is not supported because it would not correlate well + * with a sampling period. + */ +static int amd_brs_setup_filter(struct perf_event *event) +{ + u64 type = event->attr.branch_sample_type; + + /* No BRS support */ + if (!x86_pmu.lbr_nr) + return -EOPNOTSUPP; + + /* Can only capture all branches, i.e., no filtering */ + if ((type & ~PERF_SAMPLE_BRANCH_PLM_ALL) != PERF_SAMPLE_BRANCH_ANY) + return -EINVAL; + + return 0; +} + +static inline int amd_is_brs_event(struct perf_event *e) +{ + return (e->hw.config & AMD64_RAW_EVENT_MASK) == AMD_FAM19H_BRS_EVENT; +} + +int amd_brs_hw_config(struct perf_event *event) +{ + int ret = 0; + + /* + * Due to interrupt holding, BRS is not recommended in + * counting mode. + */ + if (!is_sampling_event(event)) + return -EINVAL; + + /* + * Due to the way BRS operates by holding the interrupt until + * lbr_nr entries have been captured, it does not make sense + * to allow sampling on BRS with an event that does not match + * what BRS is capturing, i.e., retired taken branches. + * Otherwise the correlation with the event's period is even + * more loose: + * + * With retired taken branch: + * Effective P = P + 16 + X + * With any other event: + * Effective P = P + Y + X + * + * Where X is the number of taken branches due to interrupt + * skid. Skid is large. + * + * Where Y is the occurences of the event while BRS is + * capturing the lbr_nr entries. + * + * By using retired taken branches, we limit the impact on the + * Y variable. We know it cannot be more than the depth of + * BRS. + */ + if (!amd_is_brs_event(event)) + return -EINVAL; + + /* + * BRS implementation does not work with frequency mode + * reprogramming of the period. + */ + if (event->attr.freq) + return -EINVAL; + /* + * The kernel subtracts BRS depth from period, so it must + * be big enough. + */ + if (event->attr.sample_period <= x86_pmu.lbr_nr) + return -EINVAL; + + /* + * Check if we can allow PERF_SAMPLE_BRANCH_STACK + */ + ret = amd_brs_setup_filter(event); + + /* only set in case of success */ + if (!ret) + event->hw.flags |= PERF_X86_EVENT_AMD_BRS; + + return ret; +} + +/* tos = top of stack, i.e., last valid entry written */ +static inline int amd_brs_get_tos(union amd_debug_extn_cfg *cfg) +{ + /* + * msroff: index of next entry to write so top-of-stack is one off + * if BRS is full then msroff is set back to 0. + */ + return (cfg->msroff ? cfg->msroff : x86_pmu.lbr_nr) - 1; +} + +/* + * make sure we have a sane BRS offset to begin with + * especially with kexec + */ +void amd_brs_reset(void) +{ + if (!cpu_feature_enabled(X86_FEATURE_BRS)) + return; + + /* + * Reset config + */ + set_debug_extn_cfg(0); + + /* + * Mark first entry as poisoned + */ + wrmsrl(brs_to(0), BRS_POISON); +} + +int __init amd_brs_init(void) +{ + if (!amd_brs_detect()) + return -EOPNOTSUPP; + + pr_cont("%d-deep BRS, ", x86_pmu.lbr_nr); + + return 0; +} + +void amd_brs_enable(void) +{ + struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); + union amd_debug_extn_cfg cfg; + + /* Activate only on first user */ + if (++cpuc->brs_active > 1) + return; + + cfg.val = 0; /* reset all fields */ + cfg.brsmen = 1; /* enable branch sampling */ + + /* Set enable bit */ + set_debug_extn_cfg(cfg.val); +} + +void amd_brs_enable_all(void) +{ + struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); + if (cpuc->lbr_users) + amd_brs_enable(); +} + +void amd_brs_disable(void) +{ + struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); + union amd_debug_extn_cfg cfg; + + /* Check if active (could be disabled via x86_pmu_disable_all()) */ + if (!cpuc->brs_active) + return; + + /* Only disable for last user */ + if (--cpuc->brs_active) + return; + + /* + * Clear the brsmen bit but preserve the others as they contain + * useful state such as vb and msroff + */ + cfg.val = get_debug_extn_cfg(); + + /* + * When coming in on interrupt and BRS is full, then hw will have + * already stopped BRS, no need to issue wrmsr again + */ + if (cfg.brsmen) { + cfg.brsmen = 0; + set_debug_extn_cfg(cfg.val); + } +} + +void amd_brs_disable_all(void) +{ + struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); + if (cpuc->lbr_users) + amd_brs_disable(); +} + +static bool amd_brs_match_plm(struct perf_event *event, u64 to) +{ + int type = event->attr.branch_sample_type; + int plm_k = PERF_SAMPLE_BRANCH_KERNEL | PERF_SAMPLE_BRANCH_HV; + int plm_u = PERF_SAMPLE_BRANCH_USER; + + if (!(type & plm_k) && kernel_ip(to)) + return 0; + + if (!(type & plm_u) && !kernel_ip(to)) + return 0; + + return 1; +} + +/* + * Caller must ensure amd_brs_inuse() is true before calling + * return: + */ +void amd_brs_drain(void) +{ + struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); + struct perf_event *event = cpuc->events[0]; + struct perf_branch_entry *br = cpuc->lbr_entries; + union amd_debug_extn_cfg cfg; + u32 i, nr = 0, num, tos, start; + u32 shift = 64 - boot_cpu_data.x86_virt_bits; + + /* + * BRS event forced on PMC0, + * so check if there is an event. + * It is possible to have lbr_users > 0 but the event + * not yet scheduled due to long latency PMU irq + */ + if (!event) + goto empty; + + cfg.val = get_debug_extn_cfg(); + + /* Sanity check [0-x86_pmu.lbr_nr] */ + if (WARN_ON_ONCE(cfg.msroff >= x86_pmu.lbr_nr)) + goto empty; + + /* No valid branch */ + if (cfg.vb == 0) + goto empty; + + /* + * msr.off points to next entry to be written + * tos = most recent entry index = msr.off - 1 + * BRS register buffer saturates, so we know we have + * start < tos and that we have to read from start to tos + */ + start = 0; + tos = amd_brs_get_tos(&cfg); + + num = tos - start + 1; + + /* + * BRS is only one pass (saturation) from MSROFF to depth-1 + * MSROFF wraps to zero when buffer is full + */ + for (i = 0; i < num; i++) { + u32 brs_idx = tos - i; + u64 from, to; + + rdmsrl(brs_to(brs_idx), to); + + /* Entry does not belong to us (as marked by kernel) */ + if (to == BRS_POISON) + break; + + /* + * Sign-extend SAMP_BR_TO to 64 bits, bits 61-63 are reserved. + * Necessary to generate proper virtual addresses suitable for + * symbolization + */ + to = (u64)(((s64)to << shift) >> shift); + + if (!amd_brs_match_plm(event, to)) + continue; + + rdmsrl(brs_from(brs_idx), from); + + perf_clear_branch_entry_bitfields(br+nr); + + br[nr].from = from; + br[nr].to = to; + + nr++; + } +empty: + /* Record number of sampled branches */ + cpuc->lbr_stack.nr = nr; +} + +/* + * Poison most recent entry to prevent reuse by next task + * required because BRS entry are not tagged by PID + */ +static void amd_brs_poison_buffer(void) +{ + union amd_debug_extn_cfg cfg; + unsigned int idx; + + /* Get current state */ + cfg.val = get_debug_extn_cfg(); + + /* idx is most recently written entry */ + idx = amd_brs_get_tos(&cfg); + + /* Poison target of entry */ + wrmsrl(brs_to(idx), BRS_POISON); +} + +/* + * On context switch in, we need to make sure no samples from previous user + * are left in the BRS. + * + * On ctxswin, sched_in = true, called after the PMU has started + * On ctxswout, sched_in = false, called before the PMU is stopped + */ +void amd_pmu_brs_sched_task(struct perf_event_pmu_context *pmu_ctx, bool sched_in) +{ + struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); + + /* no active users */ + if (!cpuc->lbr_users) + return; + + /* + * On context switch in, we need to ensure we do not use entries + * from previous BRS user on that CPU, so we poison the buffer as + * a faster way compared to resetting all entries. + */ + if (sched_in) + amd_brs_poison_buffer(); +} + +/* + * called from ACPI processor_idle.c or acpi_pad.c + * with interrupts disabled + */ +void noinstr perf_amd_brs_lopwr_cb(bool lopwr_in) +{ + struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events); + union amd_debug_extn_cfg cfg; + + /* + * on mwait in, we may end up in non C0 state. + * we must disable branch sampling to avoid holding the NMI + * for too long. We disable it in hardware but we + * keep the state in cpuc, so we can re-enable. + * + * The hardware will deliver the NMI if needed when brsmen cleared + */ + if (cpuc->brs_active) { + cfg.val = get_debug_extn_cfg(); + cfg.brsmen = !lopwr_in; + set_debug_extn_cfg(cfg.val); + } +} + +DEFINE_STATIC_CALL_NULL(perf_lopwr_cb, perf_amd_brs_lopwr_cb); +EXPORT_STATIC_CALL_TRAMP_GPL(perf_lopwr_cb); + +void __init amd_brs_lopwr_init(void) +{ + static_call_update(perf_lopwr_cb, perf_amd_brs_lopwr_cb); +} |