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author | 2023-02-21 18:24:12 -0800 | |
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committer | 2023-02-21 18:24:12 -0800 | |
commit | 5b7c4cabbb65f5c469464da6c5f614cbd7f730f2 (patch) | |
tree | cc5c2d0a898769fd59549594fedb3ee6f84e59a0 /kernel/trace/trace_irqsoff.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 'kernel/trace/trace_irqsoff.c')
-rw-r--r-- | kernel/trace/trace_irqsoff.c | 751 |
1 files changed, 751 insertions, 0 deletions
diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c new file mode 100644 index 000000000..590b3d51a --- /dev/null +++ b/kernel/trace/trace_irqsoff.c @@ -0,0 +1,751 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * trace irqs off critical timings + * + * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com> + * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com> + * + * From code in the latency_tracer, that is: + * + * Copyright (C) 2004-2006 Ingo Molnar + * Copyright (C) 2004 Nadia Yvette Chambers + */ +#include <linux/kallsyms.h> +#include <linux/uaccess.h> +#include <linux/module.h> +#include <linux/ftrace.h> +#include <linux/kprobes.h> + +#include "trace.h" + +#include <trace/events/preemptirq.h> + +#if defined(CONFIG_IRQSOFF_TRACER) || defined(CONFIG_PREEMPT_TRACER) +static struct trace_array *irqsoff_trace __read_mostly; +static int tracer_enabled __read_mostly; + +static DEFINE_PER_CPU(int, tracing_cpu); + +static DEFINE_RAW_SPINLOCK(max_trace_lock); + +enum { + TRACER_IRQS_OFF = (1 << 1), + TRACER_PREEMPT_OFF = (1 << 2), +}; + +static int trace_type __read_mostly; + +static int save_flags; + +static void stop_irqsoff_tracer(struct trace_array *tr, int graph); +static int start_irqsoff_tracer(struct trace_array *tr, int graph); + +#ifdef CONFIG_PREEMPT_TRACER +static inline int +preempt_trace(int pc) +{ + return ((trace_type & TRACER_PREEMPT_OFF) && pc); +} +#else +# define preempt_trace(pc) (0) +#endif + +#ifdef CONFIG_IRQSOFF_TRACER +static inline int +irq_trace(void) +{ + return ((trace_type & TRACER_IRQS_OFF) && + irqs_disabled()); +} +#else +# define irq_trace() (0) +#endif + +#ifdef CONFIG_FUNCTION_GRAPH_TRACER +static int irqsoff_display_graph(struct trace_array *tr, int set); +# define is_graph(tr) ((tr)->trace_flags & TRACE_ITER_DISPLAY_GRAPH) +#else +static inline int irqsoff_display_graph(struct trace_array *tr, int set) +{ + return -EINVAL; +} +# define is_graph(tr) false +#endif + +/* + * Sequence count - we record it when starting a measurement and + * skip the latency if the sequence has changed - some other section + * did a maximum and could disturb our measurement with serial console + * printouts, etc. Truly coinciding maximum latencies should be rare + * and what happens together happens separately as well, so this doesn't + * decrease the validity of the maximum found: + */ +static __cacheline_aligned_in_smp unsigned long max_sequence; + +#ifdef CONFIG_FUNCTION_TRACER +/* + * Prologue for the preempt and irqs off function tracers. + * + * Returns 1 if it is OK to continue, and data->disabled is + * incremented. + * 0 if the trace is to be ignored, and data->disabled + * is kept the same. + * + * Note, this function is also used outside this ifdef but + * inside the #ifdef of the function graph tracer below. + * This is OK, since the function graph tracer is + * dependent on the function tracer. + */ +static int func_prolog_dec(struct trace_array *tr, + struct trace_array_cpu **data, + unsigned long *flags) +{ + long disabled; + int cpu; + + /* + * Does not matter if we preempt. We test the flags + * afterward, to see if irqs are disabled or not. + * If we preempt and get a false positive, the flags + * test will fail. + */ + cpu = raw_smp_processor_id(); + if (likely(!per_cpu(tracing_cpu, cpu))) + return 0; + + local_save_flags(*flags); + /* + * Slight chance to get a false positive on tracing_cpu, + * although I'm starting to think there isn't a chance. + * Leave this for now just to be paranoid. + */ + if (!irqs_disabled_flags(*flags) && !preempt_count()) + return 0; + + *data = per_cpu_ptr(tr->array_buffer.data, cpu); + disabled = atomic_inc_return(&(*data)->disabled); + + if (likely(disabled == 1)) + return 1; + + atomic_dec(&(*data)->disabled); + + return 0; +} + +/* + * irqsoff uses its own tracer function to keep the overhead down: + */ +static void +irqsoff_tracer_call(unsigned long ip, unsigned long parent_ip, + struct ftrace_ops *op, struct ftrace_regs *fregs) +{ + struct trace_array *tr = irqsoff_trace; + struct trace_array_cpu *data; + unsigned long flags; + unsigned int trace_ctx; + + if (!func_prolog_dec(tr, &data, &flags)) + return; + + trace_ctx = tracing_gen_ctx_flags(flags); + + trace_function(tr, ip, parent_ip, trace_ctx); + + atomic_dec(&data->disabled); +} +#endif /* CONFIG_FUNCTION_TRACER */ + +#ifdef CONFIG_FUNCTION_GRAPH_TRACER +static int irqsoff_display_graph(struct trace_array *tr, int set) +{ + int cpu; + + if (!(is_graph(tr) ^ set)) + return 0; + + stop_irqsoff_tracer(irqsoff_trace, !set); + + for_each_possible_cpu(cpu) + per_cpu(tracing_cpu, cpu) = 0; + + tr->max_latency = 0; + tracing_reset_online_cpus(&irqsoff_trace->array_buffer); + + return start_irqsoff_tracer(irqsoff_trace, set); +} + +static int irqsoff_graph_entry(struct ftrace_graph_ent *trace) +{ + struct trace_array *tr = irqsoff_trace; + struct trace_array_cpu *data; + unsigned long flags; + unsigned int trace_ctx; + int ret; + + if (ftrace_graph_ignore_func(trace)) + return 0; + /* + * Do not trace a function if it's filtered by set_graph_notrace. + * Make the index of ret stack negative to indicate that it should + * ignore further functions. But it needs its own ret stack entry + * to recover the original index in order to continue tracing after + * returning from the function. + */ + if (ftrace_graph_notrace_addr(trace->func)) + return 1; + + if (!func_prolog_dec(tr, &data, &flags)) + return 0; + + trace_ctx = tracing_gen_ctx_flags(flags); + ret = __trace_graph_entry(tr, trace, trace_ctx); + atomic_dec(&data->disabled); + + return ret; +} + +static void irqsoff_graph_return(struct ftrace_graph_ret *trace) +{ + struct trace_array *tr = irqsoff_trace; + struct trace_array_cpu *data; + unsigned long flags; + unsigned int trace_ctx; + + ftrace_graph_addr_finish(trace); + + if (!func_prolog_dec(tr, &data, &flags)) + return; + + trace_ctx = tracing_gen_ctx_flags(flags); + __trace_graph_return(tr, trace, trace_ctx); + atomic_dec(&data->disabled); +} + +static struct fgraph_ops fgraph_ops = { + .entryfunc = &irqsoff_graph_entry, + .retfunc = &irqsoff_graph_return, +}; + +static void irqsoff_trace_open(struct trace_iterator *iter) +{ + if (is_graph(iter->tr)) + graph_trace_open(iter); + +} + +static void irqsoff_trace_close(struct trace_iterator *iter) +{ + if (iter->private) + graph_trace_close(iter); +} + +#define GRAPH_TRACER_FLAGS (TRACE_GRAPH_PRINT_CPU | \ + TRACE_GRAPH_PRINT_PROC | \ + TRACE_GRAPH_PRINT_REL_TIME | \ + TRACE_GRAPH_PRINT_DURATION) + +static enum print_line_t irqsoff_print_line(struct trace_iterator *iter) +{ + /* + * In graph mode call the graph tracer output function, + * otherwise go with the TRACE_FN event handler + */ + if (is_graph(iter->tr)) + return print_graph_function_flags(iter, GRAPH_TRACER_FLAGS); + + return TRACE_TYPE_UNHANDLED; +} + +static void irqsoff_print_header(struct seq_file *s) +{ + struct trace_array *tr = irqsoff_trace; + + if (is_graph(tr)) + print_graph_headers_flags(s, GRAPH_TRACER_FLAGS); + else + trace_default_header(s); +} + +static void +__trace_function(struct trace_array *tr, + unsigned long ip, unsigned long parent_ip, + unsigned int trace_ctx) +{ + if (is_graph(tr)) + trace_graph_function(tr, ip, parent_ip, trace_ctx); + else + trace_function(tr, ip, parent_ip, trace_ctx); +} + +#else +#define __trace_function trace_function + +static enum print_line_t irqsoff_print_line(struct trace_iterator *iter) +{ + return TRACE_TYPE_UNHANDLED; +} + +static void irqsoff_trace_open(struct trace_iterator *iter) { } +static void irqsoff_trace_close(struct trace_iterator *iter) { } + +#ifdef CONFIG_FUNCTION_TRACER +static void irqsoff_print_header(struct seq_file *s) +{ + trace_default_header(s); +} +#else +static void irqsoff_print_header(struct seq_file *s) +{ + trace_latency_header(s); +} +#endif /* CONFIG_FUNCTION_TRACER */ +#endif /* CONFIG_FUNCTION_GRAPH_TRACER */ + +/* + * Should this new latency be reported/recorded? + */ +static bool report_latency(struct trace_array *tr, u64 delta) +{ + if (tracing_thresh) { + if (delta < tracing_thresh) + return false; + } else { + if (delta <= tr->max_latency) + return false; + } + return true; +} + +static void +check_critical_timing(struct trace_array *tr, + struct trace_array_cpu *data, + unsigned long parent_ip, + int cpu) +{ + u64 T0, T1, delta; + unsigned long flags; + unsigned int trace_ctx; + + T0 = data->preempt_timestamp; + T1 = ftrace_now(cpu); + delta = T1-T0; + + trace_ctx = tracing_gen_ctx(); + + if (!report_latency(tr, delta)) + goto out; + + raw_spin_lock_irqsave(&max_trace_lock, flags); + + /* check if we are still the max latency */ + if (!report_latency(tr, delta)) + goto out_unlock; + + __trace_function(tr, CALLER_ADDR0, parent_ip, trace_ctx); + /* Skip 5 functions to get to the irq/preempt enable function */ + __trace_stack(tr, trace_ctx, 5); + + if (data->critical_sequence != max_sequence) + goto out_unlock; + + data->critical_end = parent_ip; + + if (likely(!is_tracing_stopped())) { + tr->max_latency = delta; + update_max_tr_single(tr, current, cpu); + } + + max_sequence++; + +out_unlock: + raw_spin_unlock_irqrestore(&max_trace_lock, flags); + +out: + data->critical_sequence = max_sequence; + data->preempt_timestamp = ftrace_now(cpu); + __trace_function(tr, CALLER_ADDR0, parent_ip, trace_ctx); +} + +static nokprobe_inline void +start_critical_timing(unsigned long ip, unsigned long parent_ip) +{ + int cpu; + struct trace_array *tr = irqsoff_trace; + struct trace_array_cpu *data; + + if (!tracer_enabled || !tracing_is_enabled()) + return; + + cpu = raw_smp_processor_id(); + + if (per_cpu(tracing_cpu, cpu)) + return; + + data = per_cpu_ptr(tr->array_buffer.data, cpu); + + if (unlikely(!data) || atomic_read(&data->disabled)) + return; + + atomic_inc(&data->disabled); + + data->critical_sequence = max_sequence; + data->preempt_timestamp = ftrace_now(cpu); + data->critical_start = parent_ip ? : ip; + + __trace_function(tr, ip, parent_ip, tracing_gen_ctx()); + + per_cpu(tracing_cpu, cpu) = 1; + + atomic_dec(&data->disabled); +} + +static nokprobe_inline void +stop_critical_timing(unsigned long ip, unsigned long parent_ip) +{ + int cpu; + struct trace_array *tr = irqsoff_trace; + struct trace_array_cpu *data; + unsigned int trace_ctx; + + cpu = raw_smp_processor_id(); + /* Always clear the tracing cpu on stopping the trace */ + if (unlikely(per_cpu(tracing_cpu, cpu))) + per_cpu(tracing_cpu, cpu) = 0; + else + return; + + if (!tracer_enabled || !tracing_is_enabled()) + return; + + data = per_cpu_ptr(tr->array_buffer.data, cpu); + + if (unlikely(!data) || + !data->critical_start || atomic_read(&data->disabled)) + return; + + atomic_inc(&data->disabled); + + trace_ctx = tracing_gen_ctx(); + __trace_function(tr, ip, parent_ip, trace_ctx); + check_critical_timing(tr, data, parent_ip ? : ip, cpu); + data->critical_start = 0; + atomic_dec(&data->disabled); +} + +/* start and stop critical timings used to for stoppage (in idle) */ +void start_critical_timings(void) +{ + if (preempt_trace(preempt_count()) || irq_trace()) + start_critical_timing(CALLER_ADDR0, CALLER_ADDR1); +} +EXPORT_SYMBOL_GPL(start_critical_timings); +NOKPROBE_SYMBOL(start_critical_timings); + +void stop_critical_timings(void) +{ + if (preempt_trace(preempt_count()) || irq_trace()) + stop_critical_timing(CALLER_ADDR0, CALLER_ADDR1); +} +EXPORT_SYMBOL_GPL(stop_critical_timings); +NOKPROBE_SYMBOL(stop_critical_timings); + +#ifdef CONFIG_FUNCTION_TRACER +static bool function_enabled; + +static int register_irqsoff_function(struct trace_array *tr, int graph, int set) +{ + int ret; + + /* 'set' is set if TRACE_ITER_FUNCTION is about to be set */ + if (function_enabled || (!set && !(tr->trace_flags & TRACE_ITER_FUNCTION))) + return 0; + + if (graph) + ret = register_ftrace_graph(&fgraph_ops); + else + ret = register_ftrace_function(tr->ops); + + if (!ret) + function_enabled = true; + + return ret; +} + +static void unregister_irqsoff_function(struct trace_array *tr, int graph) +{ + if (!function_enabled) + return; + + if (graph) + unregister_ftrace_graph(&fgraph_ops); + else + unregister_ftrace_function(tr->ops); + + function_enabled = false; +} + +static int irqsoff_function_set(struct trace_array *tr, u32 mask, int set) +{ + if (!(mask & TRACE_ITER_FUNCTION)) + return 0; + + if (set) + register_irqsoff_function(tr, is_graph(tr), 1); + else + unregister_irqsoff_function(tr, is_graph(tr)); + return 1; +} +#else +static int register_irqsoff_function(struct trace_array *tr, int graph, int set) +{ + return 0; +} +static void unregister_irqsoff_function(struct trace_array *tr, int graph) { } +static inline int irqsoff_function_set(struct trace_array *tr, u32 mask, int set) +{ + return 0; +} +#endif /* CONFIG_FUNCTION_TRACER */ + +static int irqsoff_flag_changed(struct trace_array *tr, u32 mask, int set) +{ + struct tracer *tracer = tr->current_trace; + + if (irqsoff_function_set(tr, mask, set)) + return 0; + +#ifdef CONFIG_FUNCTION_GRAPH_TRACER + if (mask & TRACE_ITER_DISPLAY_GRAPH) + return irqsoff_display_graph(tr, set); +#endif + + return trace_keep_overwrite(tracer, mask, set); +} + +static int start_irqsoff_tracer(struct trace_array *tr, int graph) +{ + int ret; + + ret = register_irqsoff_function(tr, graph, 0); + + if (!ret && tracing_is_enabled()) + tracer_enabled = 1; + else + tracer_enabled = 0; + + return ret; +} + +static void stop_irqsoff_tracer(struct trace_array *tr, int graph) +{ + tracer_enabled = 0; + + unregister_irqsoff_function(tr, graph); +} + +static bool irqsoff_busy; + +static int __irqsoff_tracer_init(struct trace_array *tr) +{ + if (irqsoff_busy) + return -EBUSY; + + save_flags = tr->trace_flags; + + /* non overwrite screws up the latency tracers */ + set_tracer_flag(tr, TRACE_ITER_OVERWRITE, 1); + set_tracer_flag(tr, TRACE_ITER_LATENCY_FMT, 1); + /* without pause, we will produce garbage if another latency occurs */ + set_tracer_flag(tr, TRACE_ITER_PAUSE_ON_TRACE, 1); + + tr->max_latency = 0; + irqsoff_trace = tr; + /* make sure that the tracer is visible */ + smp_wmb(); + + ftrace_init_array_ops(tr, irqsoff_tracer_call); + + /* Only toplevel instance supports graph tracing */ + if (start_irqsoff_tracer(tr, (tr->flags & TRACE_ARRAY_FL_GLOBAL && + is_graph(tr)))) + printk(KERN_ERR "failed to start irqsoff tracer\n"); + + irqsoff_busy = true; + return 0; +} + +static void __irqsoff_tracer_reset(struct trace_array *tr) +{ + int lat_flag = save_flags & TRACE_ITER_LATENCY_FMT; + int overwrite_flag = save_flags & TRACE_ITER_OVERWRITE; + int pause_flag = save_flags & TRACE_ITER_PAUSE_ON_TRACE; + + stop_irqsoff_tracer(tr, is_graph(tr)); + + set_tracer_flag(tr, TRACE_ITER_LATENCY_FMT, lat_flag); + set_tracer_flag(tr, TRACE_ITER_OVERWRITE, overwrite_flag); + set_tracer_flag(tr, TRACE_ITER_PAUSE_ON_TRACE, pause_flag); + ftrace_reset_array_ops(tr); + + irqsoff_busy = false; +} + +static void irqsoff_tracer_start(struct trace_array *tr) +{ + tracer_enabled = 1; +} + +static void irqsoff_tracer_stop(struct trace_array *tr) +{ + tracer_enabled = 0; +} + +#ifdef CONFIG_IRQSOFF_TRACER +/* + * We are only interested in hardirq on/off events: + */ +void tracer_hardirqs_on(unsigned long a0, unsigned long a1) +{ + if (!preempt_trace(preempt_count()) && irq_trace()) + stop_critical_timing(a0, a1); +} +NOKPROBE_SYMBOL(tracer_hardirqs_on); + +void tracer_hardirqs_off(unsigned long a0, unsigned long a1) +{ + if (!preempt_trace(preempt_count()) && irq_trace()) + start_critical_timing(a0, a1); +} +NOKPROBE_SYMBOL(tracer_hardirqs_off); + +static int irqsoff_tracer_init(struct trace_array *tr) +{ + trace_type = TRACER_IRQS_OFF; + + return __irqsoff_tracer_init(tr); +} + +static void irqsoff_tracer_reset(struct trace_array *tr) +{ + __irqsoff_tracer_reset(tr); +} + +static struct tracer irqsoff_tracer __read_mostly = +{ + .name = "irqsoff", + .init = irqsoff_tracer_init, + .reset = irqsoff_tracer_reset, + .start = irqsoff_tracer_start, + .stop = irqsoff_tracer_stop, + .print_max = true, + .print_header = irqsoff_print_header, + .print_line = irqsoff_print_line, + .flag_changed = irqsoff_flag_changed, +#ifdef CONFIG_FTRACE_SELFTEST + .selftest = trace_selftest_startup_irqsoff, +#endif + .open = irqsoff_trace_open, + .close = irqsoff_trace_close, + .allow_instances = true, + .use_max_tr = true, +}; +#endif /* CONFIG_IRQSOFF_TRACER */ + +#ifdef CONFIG_PREEMPT_TRACER +void tracer_preempt_on(unsigned long a0, unsigned long a1) +{ + if (preempt_trace(preempt_count()) && !irq_trace()) + stop_critical_timing(a0, a1); +} + +void tracer_preempt_off(unsigned long a0, unsigned long a1) +{ + if (preempt_trace(preempt_count()) && !irq_trace()) + start_critical_timing(a0, a1); +} + +static int preemptoff_tracer_init(struct trace_array *tr) +{ + trace_type = TRACER_PREEMPT_OFF; + + return __irqsoff_tracer_init(tr); +} + +static void preemptoff_tracer_reset(struct trace_array *tr) +{ + __irqsoff_tracer_reset(tr); +} + +static struct tracer preemptoff_tracer __read_mostly = +{ + .name = "preemptoff", + .init = preemptoff_tracer_init, + .reset = preemptoff_tracer_reset, + .start = irqsoff_tracer_start, + .stop = irqsoff_tracer_stop, + .print_max = true, + .print_header = irqsoff_print_header, + .print_line = irqsoff_print_line, + .flag_changed = irqsoff_flag_changed, +#ifdef CONFIG_FTRACE_SELFTEST + .selftest = trace_selftest_startup_preemptoff, +#endif + .open = irqsoff_trace_open, + .close = irqsoff_trace_close, + .allow_instances = true, + .use_max_tr = true, +}; +#endif /* CONFIG_PREEMPT_TRACER */ + +#if defined(CONFIG_IRQSOFF_TRACER) && defined(CONFIG_PREEMPT_TRACER) + +static int preemptirqsoff_tracer_init(struct trace_array *tr) +{ + trace_type = TRACER_IRQS_OFF | TRACER_PREEMPT_OFF; + + return __irqsoff_tracer_init(tr); +} + +static void preemptirqsoff_tracer_reset(struct trace_array *tr) +{ + __irqsoff_tracer_reset(tr); +} + +static struct tracer preemptirqsoff_tracer __read_mostly = +{ + .name = "preemptirqsoff", + .init = preemptirqsoff_tracer_init, + .reset = preemptirqsoff_tracer_reset, + .start = irqsoff_tracer_start, + .stop = irqsoff_tracer_stop, + .print_max = true, + .print_header = irqsoff_print_header, + .print_line = irqsoff_print_line, + .flag_changed = irqsoff_flag_changed, +#ifdef CONFIG_FTRACE_SELFTEST + .selftest = trace_selftest_startup_preemptirqsoff, +#endif + .open = irqsoff_trace_open, + .close = irqsoff_trace_close, + .allow_instances = true, + .use_max_tr = true, +}; +#endif + +__init static int init_irqsoff_tracer(void) +{ +#ifdef CONFIG_IRQSOFF_TRACER + register_tracer(&irqsoff_tracer); +#endif +#ifdef CONFIG_PREEMPT_TRACER + register_tracer(&preemptoff_tracer); +#endif +#if defined(CONFIG_IRQSOFF_TRACER) && defined(CONFIG_PREEMPT_TRACER) + register_tracer(&preemptirqsoff_tracer); +#endif + + return 0; +} +core_initcall(init_irqsoff_tracer); +#endif /* IRQSOFF_TRACER || PREEMPTOFF_TRACER */ |