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2020-02-25bootconfig: Fix CONFIG_BOOTTIME_TRACING dependency issueMasami Hiramatsu1-1/+0
Since commit d8a953ddde5e ("bootconfig: Set CONFIG_BOOT_CONFIG=n by default") also changed the CONFIG_BOOTTIME_TRACING to select CONFIG_BOOT_CONFIG to show the boot-time tracing on the menu, it introduced wrong dependencies with BLK_DEV_INITRD as below. WARNING: unmet direct dependencies detected for BOOT_CONFIG Depends on [n]: BLK_DEV_INITRD [=n] Selected by [y]: - BOOTTIME_TRACING [=y] && TRACING_SUPPORT [=y] && FTRACE [=y] && TRACING [=y] This makes the CONFIG_BOOT_CONFIG selects CONFIG_BLK_DEV_INITRD to fix this error and make CONFIG_BOOTTIME_TRACING=n by default, so that both boot-time tracing and boot configuration off but those appear on the menu list. Link: http://lkml.kernel.org/r/158264140162.23842.11237423518607465535.stgit@devnote2 Fixes: d8a953ddde5e ("bootconfig: Set CONFIG_BOOT_CONFIG=n by default") Reported-by: Randy Dunlap <rdunlap@infradead.org> Compiled-tested-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-02-20bootconfig: Set CONFIG_BOOT_CONFIG=n by defaultMasami Hiramatsu1-1/+2
Set CONFIG_BOOT_CONFIG=n by default. This also warns user if CONFIG_BOOT_CONFIG=n but "bootconfig" is given in the kernel command line. Link: http://lkml.kernel.org/r/158220111291.26565.9036889083940367969.stgit@devnote2 Suggested-by: Steven Rostedt <rostedt@goodmis.org> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-01-30tracing: Move tracing selftests to bottom of menuSteven Rostedt (VMware)1-84/+84
Move all the tracing selftest configs to the bottom of the tracing menu. There's no reason for them to be interspersed throughout. Also, move the bootconfig menu to the top. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-01-30tracing: Move mmio tracer config up with the other tracersSteven Rostedt (VMware)1-13/+13
Move the config that enables the mmiotracer with the other tracers such that all the tracers are together. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-01-30tracing: Move tracing test module configs togetherSteven Rostedt (VMware)1-11/+11
The MMIO test module was by itself, move it to the other test modules. Also, add the text "Test module" to PREEMPTIRQ_DELAY_TEST as that create a test module as well. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-01-30tracing: Move all function tracing configs togetherSteven Rostedt (VMware)1-71/+71
The features that depend on the function tracer were spread out through the tracing menu, pull them together as it is easier to manage. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-01-30tracing: Add kprobe event command generation test moduleTom Zanussi1-0/+12
Add a test module that checks the basic functionality of the in-kernel kprobe event command generation API by creating kprobe events from a module. Link: http://lkml.kernel.org/r/97e502b204f9dba948e3fa3a4315448298218787.1580323897.git.zanussi@kernel.org Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-01-30tracing: Add synth event generation test moduleTom Zanussi1-0/+13
Add a test module that checks the basic functionality of the in-kernel synthetic event generation API by generating and tracing synthetic events from a module. Link: http://lkml.kernel.org/r/fcb4dd9eb9eefb70ab20538d3529d51642389664.1580323897.git.zanussi@kernel.org Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-01-13tracing/boot: Add boot-time tracingMasami Hiramatsu1-0/+9
Setup tracing options via extra boot config in addition to kernel command line. This adds following commands support. These are applied to the global trace instance. - ftrace.options = OPT1[,OPT2...] Enable given ftrace options. - ftrace.trace_clock = CLOCK Set given CLOCK to ftrace's trace_clock. - ftrace.buffer_size = SIZE Configure ftrace buffer size to SIZE. You can use "KB" or "MB" for that SIZE. - ftrace.events = EVENT[, EVENT2...] Enable given events on boot. You can use a wild card in EVENT. - ftrace.tracer = TRACER Set TRACER to current tracer on boot. (e.g. function) Note that this is NOT replacing the kernel parameters, because this boot config based setting is later than that. If you want to trace earlier boot events, you still need kernel parameters. Link: http://lkml.kernel.org/r/157867237723.17873.17494943526320587488.stgit@devnote2 Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-12-04Merge tag 'trace-v5.5-2' of ↵Linus Torvalds1-0/+9
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull more tracing updates from Steven Rostedt: "Two fixes and one patch that was missed: Fixes: - Missing __print_hex_dump undef for processing new function in trace events - Stop WARN_ON messages when lockdown disables tracing on boot up Enhancement: - Debug option to inject trace events from userspace (for rasdaemon)" The enhancement has its own config option and is non invasive. It's been discussed for sever months and should have been added to my original push, but I never pulled it into my queue. * tag 'trace-v5.5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing: Do not create directories if lockdown is in affect tracing: Introduce trace event injection tracing: Fix __print_hex_dump scope
2019-12-02tracing: Introduce trace event injectionCong Wang1-0/+9
We have been trying to use rasdaemon to monitor hardware errors like correctable memory errors. rasdaemon uses trace events to monitor various hardware errors. In order to test it, we have to inject some hardware errors, unfortunately not all of them provide error injections. MCE does provide a way to inject MCE errors, but errors like PCI error and devlink error don't, it is not easy to add error injection to each of them. Instead, it is relatively easier to just allow users to inject trace events in a generic way so that all trace events can be injected. This patch introduces trace event injection, where a new 'inject' is added to each tracepoint directory. Users could write into this file with key=value pairs to specify the value of each fields of the trace event, all unspecified fields are set to zero values by default. For example, for the net/net_dev_queue tracepoint, we can inject: INJECT=/sys/kernel/debug/tracing/events/net/net_dev_queue/inject echo "" > $INJECT echo "name='test'" > $INJECT echo "name='test' len=1024" > $INJECT cat /sys/kernel/debug/tracing/trace ... <...>-614 [000] .... 36.571483: net_dev_queue: dev= skbaddr=00000000fbf338c2 len=0 <...>-614 [001] .... 136.588252: net_dev_queue: dev=test skbaddr=00000000fbf338c2 len=0 <...>-614 [001] .N.. 208.431878: net_dev_queue: dev=test skbaddr=00000000fbf338c2 len=1024 Triggers could be triggered as usual too: echo "stacktrace if len == 1025" > /sys/kernel/debug/tracing/events/net/net_dev_queue/trigger echo "len=1025" > $INJECT cat /sys/kernel/debug/tracing/trace ... bash-614 [000] .... 36.571483: net_dev_queue: dev= skbaddr=00000000fbf338c2 len=0 bash-614 [001] .... 136.588252: net_dev_queue: dev=test skbaddr=00000000fbf338c2 len=0 bash-614 [001] .N.. 208.431878: net_dev_queue: dev=test skbaddr=00000000fbf338c2 len=1024 bash-614 [001] .N.1 284.236349: <stack trace> => event_inject_write => vfs_write => ksys_write => do_syscall_64 => entry_SYSCALL_64_after_hwframe The only thing that can't be injected is string pointers as they require constant string pointers, this can't be done at run time. Link: http://lkml.kernel.org/r/20191130045218.18979-1-xiyou.wangcong@gmail.com Cc: Ingo Molnar <mingo@redhat.com> Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-27Merge tag 'trace-v5.5' of ↵Linus Torvalds1-9/+17
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: "New tracing features: - New PERMANENT flag to ftrace_ops when attaching a callback to a function. As /proc/sys/kernel/ftrace_enabled when set to zero will disable all attached callbacks in ftrace, this has a detrimental impact on live kernel tracing, as it disables all that it patched. If a ftrace_ops is registered to ftrace with the PERMANENT flag set, it will prevent ftrace_enabled from being disabled, and if ftrace_enabled is already disabled, it will prevent a ftrace_ops with PREMANENT flag set from being registered. - New register_ftrace_direct(). As eBPF would like to register its own trampolines to be called by the ftrace nop locations directly, without going through the ftrace trampoline, this function has been added. This allows for eBPF trampolines to live along side of ftrace, perf, kprobe and live patching. It also utilizes the ftrace enabled_functions file that keeps track of functions that have been modified in the kernel, to allow for security auditing. - Allow for kernel internal use of ftrace instances. Subsystems in the kernel can now create and destroy their own tracing instances which allows them to have their own tracing buffer, and be able to record events without worrying about other users from writing over their data. - New seq_buf_hex_dump() that lets users use the hex_dump() in their seq_buf usage. - Notifications now added to tracing_max_latency to allow user space to know when a new max latency is hit by one of the latency tracers. - Wider spread use of generic compare operations for use of bsearch and friends. - More synthetic event fields may be defined (32 up from 16) - Use of xarray for architectures with sparse system calls, for the system call trace events. This along with small clean ups and fixes" * tag 'trace-v5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (51 commits) tracing: Enable syscall optimization for MIPS tracing: Use xarray for syscall trace events tracing: Sample module to demonstrate kernel access to Ftrace instances. tracing: Adding new functions for kernel access to Ftrace instances tracing: Fix Kconfig indentation ring-buffer: Fix typos in function ring_buffer_producer ftrace: Use BIT() macro ftrace: Return ENOTSUPP when DYNAMIC_FTRACE_WITH_DIRECT_CALLS is not configured ftrace: Rename ftrace_graph_stub to ftrace_stub_graph ftrace: Add a helper function to modify_ftrace_direct() to allow arch optimization ftrace: Add helper find_direct_entry() to consolidate code ftrace: Add another check for match in register_ftrace_direct() ftrace: Fix accounting bug with direct->count in register_ftrace_direct() ftrace/selftests: Fix spelling mistake "wakeing" -> "waking" tracing: Increase SYNTH_FIELDS_MAX for synthetic_events ftrace/samples: Add a sample module that implements modify_ftrace_direct() ftrace: Add modify_ftrace_direct() tracing: Add missing "inline" in stub function of latency_fsnotify() tracing: Remove stray tab in TRACE_EVAL_MAP_FILE's help text tracing: Use seq_buf_hex_dump() to dump buffers ...
2019-11-22tracing: Fix Kconfig indentationKrzysztof Kozlowski1-4/+4
Adjust indentation from spaces to tab (+optional two spaces) as in coding style with command like: $ sed -e 's/^ /\t/' -i */Kconfig Link: http://lkml.kernel.org/r/20191120133807.12741-1-krzk@kernel.org Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-22tracing: Remove unnecessary DEBUG_FS dependencyKusanagi Kouichi1-1/+0
Tracing replaced debugfs with tracefs. Signed-off-by: Kusanagi Kouichi <slash@ac.auone-net.jp> Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Link: https://lore.kernel.org/r/20191120104350753.EWCT.12796.ppp.dion.ne.jp@dmta0009.auone-net.jp Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-11-14tracing: Remove stray tab in TRACE_EVAL_MAP_FILE's help textBorislav Petkov1-2/+2
There was a stray tab in the help text of the aforementioned config option which showed like this: The "print fmt" of the trace events will show the enum/sizeof names instead of their values. This can cause problems for user space tools ... in menuconfig. Remove it and end a sentence with a fullstop. No functional changes. Link: http://lkml.kernel.org/r/20191112174219.10933-1-bp@alien8.de Signed-off-by: Borislav Petkov <bp@suse.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13preemptirq_delay_test: Add the burst feature and a sysfs triggerViktor Rosendahl (BMW)1-3/+3
This burst feature enables the user to generate a burst of preempt/irqsoff latencies. This makes it possible to test whether we are able to detect latencies that systematically occur very close to each other. The maximum burst size is 10. We also create 10 identical test functions, so that we get 10 different backtraces; this is useful when we want to test whether we can detect all the latencies in a burst. Otherwise, there would be no easy way of differentiating between which latency in a burst was captured by the tracer. In addition, there is a sysfs trigger, so that it's not necessary to reload the module to repeat the test. The trigger will appear as /sys/kernel/preemptirq_delay_test/trigger in sysfs. Link: http://lkml.kernel.org/r/20191008220824.7911-3-viktor.rosendahl@gmail.com Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Viktor Rosendahl (BMW) <viktor.rosendahl@gmail.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13ftrace: Add register_ftrace_direct()Steven Rostedt (VMware)1-0/+8
Add the start of the functionality to allow other trampolines to use the ftrace mcount/fentry/nop location. This adds two new functions: register_ftrace_direct() and unregister_ftrace_direct() Both take two parameters: the first is the instruction address of where the mcount/fentry/nop exists, and the second is the trampoline to have that location called. This will handle cases where ftrace is already used on that same location, and will make it still work, where the registered direct called trampoline will get called after all the registered ftrace callers are handled. Currently, it will not allow for IP_MODIFY functions to be called at the same locations, which include some kprobes and live kernel patching. At this point, no architecture supports this. This is only the start of implementing the framework. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-09-18Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-nextLinus Torvalds1-1/+2
Pull networking updates from David Miller: 1) Support IPV6 RA Captive Portal Identifier, from Maciej Żenczykowski. 2) Use bio_vec in the networking instead of custom skb_frag_t, from Matthew Wilcox. 3) Make use of xmit_more in r8169 driver, from Heiner Kallweit. 4) Add devmap_hash to xdp, from Toke Høiland-Jørgensen. 5) Support all variants of 5750X bnxt_en chips, from Michael Chan. 6) More RTNL avoidance work in the core and mlx5 driver, from Vlad Buslov. 7) Add TCP syn cookies bpf helper, from Petar Penkov. 8) Add 'nettest' to selftests and use it, from David Ahern. 9) Add extack support to drop_monitor, add packet alert mode and support for HW drops, from Ido Schimmel. 10) Add VLAN offload to stmmac, from Jose Abreu. 11) Lots of devm_platform_ioremap_resource() conversions, from YueHaibing. 12) Add IONIC driver, from Shannon Nelson. 13) Several kTLS cleanups, from Jakub Kicinski. * git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1930 commits) mlxsw: spectrum_buffers: Add the ability to query the CPU port's shared buffer mlxsw: spectrum: Register CPU port with devlink mlxsw: spectrum_buffers: Prevent changing CPU port's configuration net: ena: fix incorrect update of intr_delay_resolution net: ena: fix retrieval of nonadaptive interrupt moderation intervals net: ena: fix update of interrupt moderation register net: ena: remove all old adaptive rx interrupt moderation code from ena_com net: ena: remove ena_restore_ethtool_params() and relevant fields net: ena: remove old adaptive interrupt moderation code from ena_netdev net: ena: remove code duplication in ena_com_update_nonadaptive_moderation_interval _*() net: ena: enable the interrupt_moderation in driver_supported_features net: ena: reimplement set/get_coalesce() net: ena: switch to dim algorithm for rx adaptive interrupt moderation net: ena: add intr_moder_rx_interval to struct ena_com_dev and use it net: phy: adin: implement Energy Detect Powerdown mode via phy-tunable ethtool: implement Energy Detect Powerdown support via phy-tunable xen-netfront: do not assume sk_buff_head list is empty in error handling s390/ctcm: Delete unnecessary checks before the macro call “dev_kfree_skb” net: ena: don't wake up tx queue when down drop_monitor: Better sanitize notified packets ...
2019-08-21bpf: clarify description for CONFIG_BPF_EVENTSPeter Wu1-1/+2
PERF_EVENT_IOC_SET_BPF supports uprobes since v4.3, and tracepoints since v4.7 via commit 04a22fae4cbc ("tracing, perf: Implement BPF programs attached to uprobes"), and commit 98b5c2c65c29 ("perf, bpf: allow bpf programs attach to tracepoints") respectively. Signed-off-by: Peter Wu <peter@lekensteyn.nl> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-07-31tracing: Use CONFIG_PREEMPTIONThomas Gleixner1-2/+2
CONFIG_PREEMPTION is selected by CONFIG_PREEMPT and by CONFIG_PREEMPT_RT. Both PREEMPT and PREEMPT_RT require the same functionality which today depends on CONFIG_PREEMPT. Switch the conditionals in the tracer over to CONFIG_PREEMPTION. This is the first step to make the tracer work on RT. The other small tweaks are submitted separately. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paul E. McKenney <paulmck@linux.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/20190726212124.409766323@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-07-31rcu: Use CONFIG_PREEMPTIONThomas Gleixner1-1/+1
CONFIG_PREEMPTION is selected by CONFIG_PREEMPT and by CONFIG_PREEMPT_RT. Both PREEMPT and PREEMPT_RT require the same functionality which today depends on CONFIG_PREEMPT. Switch the conditionals in RCU to use CONFIG_PREEMPTION. That's the first step towards RCU on RT. The further tweaks are work in progress. This neither touches the selftest bits which need a closer look by Paul. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paul E. McKenney <paulmck@linux.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/20190726212124.210156346@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
2019-07-18Merge tag 'trace-v5.3' of ↵Linus Torvalds1-1/+11
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: "The main changes in this release include: - Add user space specific memory reading for kprobes - Allow kprobes to be executed earlier in boot The rest are mostly just various clean ups and small fixes" * tag 'trace-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (33 commits) tracing: Make trace_get_fields() global tracing: Let filter_assign_type() detect FILTER_PTR_STRING tracing: Pass type into tracing_generic_entry_update() ftrace/selftest: Test if set_event/ftrace_pid exists before writing ftrace/selftests: Return the skip code when tracing directory not configured in kernel tracing/kprobe: Check registered state using kprobe tracing/probe: Add trace_event_call accesses APIs tracing/probe: Add probe event name and group name accesses APIs tracing/probe: Add trace flag access APIs for trace_probe tracing/probe: Add trace_event_file access APIs for trace_probe tracing/probe: Add trace_event_call register API for trace_probe tracing/probe: Add trace_probe init and free functions tracing/uprobe: Set print format when parsing command tracing/kprobe: Set print format right after parsed command kprobes: Fix to init kprobes in subsys_initcall tracepoint: Use struct_size() in kmalloc() ring-buffer: Remove HAVE_64BIT_ALIGNED_ACCESS ftrace: Enable trampoline when rec count returns back to one tracing/kprobe: Do not run kprobe boot tests if kprobe_event is on cmdline tracing: Make a separate config for trace event self tests ...
2019-05-25tracing: Make a separate config for trace event self testsSteven Rostedt (VMware)1-1/+11
The trace event self tests enable loop through *all* events, enables each one, one at a time, runs some code to trigger various events (not necessarily the same events), and checks if anything went wrong. The issue is that trace events are usually the least likely start up test to cause a problem, but they take the longest to run (because there are so many events). When one of the other tests trigger a bug, the trace event start up tests causes the bisect to take much longer, because it takes 10s of seconds to get through the trace event tests. By making them a separate config (even though they are enabled by default if start up tests are set), it is possible to turn them off and still run the other tracing start up tests much quicker. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-05-21treewide: Add SPDX license identifier - Makefile/KconfigThomas Gleixner1-0/+1
Add SPDX license identifiers to all Make/Kconfig files which: - Have no license information of any form These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-08tracing: stop making gpio tracing configurableUwe Kleine-König1-7/+0
gpio tracing was made configurable in 4.4-rc1 (commit ddd70280bf0e ("tracing: gpio: Add Kconfig option for enabling/disabling trace events")). Since then it is the only event type that can be compiled conditionally. Given that there is only little overhead I don't understand the reasoning and I was annoyed more than once that gpio events were not available without recompiling. So drop the Kconfig symbol and make gpio events available unconditionally. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
2019-02-27kbuild: compute false-positive -Wmaybe-uninitialized cases in KconfigMasahiro Yamada1-0/+1
Since -Wmaybe-uninitialized was introduced by GCC 4.7, we have patched various false positives: - commit e74fc973b6e5 ("Turn off -Wmaybe-uninitialized when building with -Os") turned off this option for -Os. - commit 815eb71e7149 ("Kbuild: disable 'maybe-uninitialized' warning for CONFIG_PROFILE_ALL_BRANCHES") turned off this option for CONFIG_PROFILE_ALL_BRANCHES - commit a76bcf557ef4 ("Kbuild: enable -Wmaybe-uninitialized warning for "make W=1"") turned off this option for GCC < 4.9 Arnd provided more explanation in https://lkml.org/lkml/2017/3/14/903 I think this looks better by shifting the logic from Makefile to Kconfig. Link: https://github.com/ClangBuiltLinux/linux/issues/350 Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> Reviewed-by: Nathan Chancellor <natechancellor@gmail.com> Tested-by: Nick Desaulniers <ndesaulniers@google.com>
2018-12-08tracing: Use dyn_event framework for synthetic eventsMasami Hiramatsu1-0/+1
Use dyn_event framework for synthetic events. This shows synthetic events on "tracing/dynamic_events" file in addition to tracing/synthetic_events interface. User can also define new events via tracing/dynamic_events with "s:" prefix. So, the new syntax is below; s:[synthetic/]EVENT_NAME TYPE ARG; [TYPE ARG;]... To remove events via tracing/dynamic_events, you can use "-:" prefix as same as other events. Link: http://lkml.kernel.org/r/154140861301.17322.15454611233735614508.stgit@devbox Reviewed-by: Tom Zanussi <tom.zanussi@linux.intel.com> Tested-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-08tracing/uprobes: Use dyn_event framework for uprobe eventsMasami Hiramatsu1-0/+1
Use dyn_event framework for uprobe events. This shows uprobe events on "dynamic_events" file. User can also define new uprobe events via dynamic_events. Link: http://lkml.kernel.org/r/154140858481.17322.9091293846515154065.stgit@devbox Reviewed-by: Tom Zanussi <tom.zanussi@linux.intel.com> Tested-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-08tracing/kprobes: Use dyn_event framework for kprobe eventsMasami Hiramatsu1-0/+1
Use dyn_event framework for kprobe events. This shows kprobe events on "tracing/dynamic_events" file. User can also define new events via tracing/dynamic_events. Link: http://lkml.kernel.org/r/154140855646.17322.6619219995865980392.stgit@devbox Reviewed-by: Tom Zanussi <tom.zanussi@linux.intel.com> Tested-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-12-08tracing: Add unified dynamic event frameworkMasami Hiramatsu1-0/+3
Add unified dynamic event framework for ftrace kprobes, uprobes and synthetic events. Those dynamic events can be co-exist on same file because those syntax doesn't overlap. This introduces a framework part which provides a unified tracefs interface and operations. Link: http://lkml.kernel.org/r/154140852824.17322.12250362185969352095.stgit@devbox Reviewed-by: Tom Zanussi <tom.zanussi@linux.intel.com> Tested-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-08-23Merge tag 'trace-v4.19-1' of ↵Linus Torvalds1-0/+12
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes from Steven Rostedt: "Masami found an off by one bug in the code that keeps "notrace" functions from being traced by kprobes. During my testing, I found that there's places that we may want to add kprobes to notrace, thus we may end up changing this code before 4.19 is released. The history behind this change is that we found that adding kprobes to various notrace functions caused the kernel to crashed. We took the safe route and decided not to allow kprobes to trace any notrace function. But because notrace is added to functions that just cause weird side effects to the function tracer, but are still safe, preventing kprobes for all notrace functios may be too much of a big hammer. One such place is __schedule() is marked notrace, to keep function tracer from doing strange recursive loops when it gets traced with NEED_RESCHED set. With this change, one can not add kprobes to the scheduler. Masami also added code to use gcov on ftrace" * tag 'trace-v4.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing/kprobes: Fix to check notrace function with correct range tracing: Allow gcov profiling on only ftrace subsystem
2018-08-21tracing: Allow gcov profiling on only ftrace subsystemMasami Hiramatsu1-0/+12
Add GCOV_PROFILE_FTRACE to allow gcov profiling on only files in ftrace subsystem. This config option will be used for checking kselftest/ftrace coverage. Link: http://lkml.kernel.org/r/153483647755.32472.4746349899604275441.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-08-20Merge tag 'trace-v4.19' of ↵Linus Torvalds1-5/+57
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: - Restructure of lockdep and latency tracers This is the biggest change. Joel Fernandes restructured the hooks from irqs and preemption disabling and enabling. He got rid of a lot of the preprocessor #ifdef mess that they caused. He turned both lockdep and the latency tracers to use trace events inserted in the preempt/irqs disabling paths. But unfortunately, these started to cause issues in corner cases. Thus, parts of the code was reverted back to where lockdep and the latency tracers just get called directly (without using the trace events). But because the original change cleaned up the code very nicely we kept that, as well as the trace events for preempt and irqs disabling, but they are limited to not being called in NMIs. - Have trace events use SRCU for "rcu idle" calls. This was required for the preempt/irqs off trace events. But it also had to not allow them to be called in NMI context. Waiting till Paul makes an NMI safe SRCU API. - New notrace SRCU API to allow trace events to use SRCU. - Addition of mcount-nop option support - SPDX headers replacing GPL templates. - Various other fixes and clean ups. - Some fixes are marked for stable, but were not fully tested before the merge window opened. * tag 'trace-v4.19' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (44 commits) tracing: Fix SPDX format headers to use C++ style comments tracing: Add SPDX License format tags to tracing files tracing: Add SPDX License format to bpf_trace.c blktrace: Add SPDX License format header s390/ftrace: Add -mfentry and -mnop-mcount support tracing: Add -mcount-nop option support tracing: Avoid calling cc-option -mrecord-mcount for every Makefile tracing: Handle CC_FLAGS_FTRACE more accurately Uprobe: Additional argument arch_uprobe to uprobe_write_opcode() Uprobes: Simplify uprobe_register() body tracepoints: Free early tracepoints after RCU is initialized uprobes: Use synchronize_rcu() not synchronize_sched() tracing: Fix synchronizing to event changes with tracepoint_synchronize_unregister() ftrace: Remove unused pointer ftrace_swapper_pid tracing: More reverting of "tracing: Centralize preemptirq tracepoints and unify their usage" tracing/irqsoff: Handle preempt_count for different configs tracing: Partial revert of "tracing: Centralize preemptirq tracepoints and unify their usage" tracing: irqsoff: Account for additional preempt_disable trace: Use rcu_dereference_raw for hooks from trace-event subsystem tracing/kprobes: Fix within_notrace_func() to check only notrace functions ...
2018-08-15tracing: Add -mcount-nop option supportVasily Gorbik1-0/+5
-mcount-nop gcc option generates the calls to the profiling functions as nops which allows to avoid patching mcount jump with NOP instructions initially. -mcount-nop gcc option will be activated if platform selects HAVE_NOP_MCOUNT and gcc actually supports it. In addition to that CC_USING_NOP_MCOUNT is defined and could be used by architectures to adapt ftrace patching behavior. Link: http://lkml.kernel.org/r/patch-3.thread-aa7b8d.git-e02ed2dc082b.your-ad-here.call-01533557518-ext-9465@work.hours Signed-off-by: Vasily Gorbik <gor@linux.ibm.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-31tracing: Centralize preemptirq tracepoints and unify their usageJoel Fernandes (Google)1-5/+17
This patch detaches the preemptirq tracepoints from the tracers and keeps it separate. Advantages: * Lockdep and irqsoff event can now run in parallel since they no longer have their own calls. * This unifies the usecase of adding hooks to an irqsoff and irqson event, and a preemptoff and preempton event. 3 users of the events exist: - Lockdep - irqsoff and preemptoff tracers - irqs and preempt trace events The unification cleans up several ifdefs and makes the code in preempt tracer and irqsoff tracers simpler. It gets rid of all the horrific ifdeferry around PROVE_LOCKING and makes configuration of the different users of the tracepoints more easy and understandable. It also gets rid of the time_* function calls from the lockdep hooks used to call into the preemptirq tracer which is not needed anymore. The negative delta in lines of code in this patch is quite large too. In the patch we introduce a new CONFIG option PREEMPTIRQ_TRACEPOINTS as a single point for registering probes onto the tracepoints. With this, the web of config options for preempt/irq toggle tracepoints and its users becomes: PREEMPT_TRACER PREEMPTIRQ_EVENTS IRQSOFF_TRACER PROVE_LOCKING | | \ | | \ (selects) / \ \ (selects) / TRACE_PREEMPT_TOGGLE ----> TRACE_IRQFLAGS \ / \ (depends on) / PREEMPTIRQ_TRACEPOINTS Other than the performance tests mentioned in the previous patch, I also ran the locking API test suite. I verified that all tests cases are passing. I also injected issues by not registering lockdep probes onto the tracepoints and I see failures to confirm that the probes are indeed working. This series + lockdep probes not registered (just to inject errors): [ 0.000000] hard-irqs-on + irq-safe-A/21: ok | ok | ok | [ 0.000000] soft-irqs-on + irq-safe-A/21: ok | ok | ok | [ 0.000000] sirq-safe-A => hirqs-on/12:FAILED|FAILED| ok | [ 0.000000] sirq-safe-A => hirqs-on/21:FAILED|FAILED| ok | [ 0.000000] hard-safe-A + irqs-on/12:FAILED|FAILED| ok | [ 0.000000] soft-safe-A + irqs-on/12:FAILED|FAILED| ok | [ 0.000000] hard-safe-A + irqs-on/21:FAILED|FAILED| ok | [ 0.000000] soft-safe-A + irqs-on/21:FAILED|FAILED| ok | [ 0.000000] hard-safe-A + unsafe-B #1/123: ok | ok | ok | [ 0.000000] soft-safe-A + unsafe-B #1/123: ok | ok | ok | With this series + lockdep probes registered, all locking tests pass: [ 0.000000] hard-irqs-on + irq-safe-A/21: ok | ok | ok | [ 0.000000] soft-irqs-on + irq-safe-A/21: ok | ok | ok | [ 0.000000] sirq-safe-A => hirqs-on/12: ok | ok | ok | [ 0.000000] sirq-safe-A => hirqs-on/21: ok | ok | ok | [ 0.000000] hard-safe-A + irqs-on/12: ok | ok | ok | [ 0.000000] soft-safe-A + irqs-on/12: ok | ok | ok | [ 0.000000] hard-safe-A + irqs-on/21: ok | ok | ok | [ 0.000000] soft-safe-A + irqs-on/21: ok | ok | ok | [ 0.000000] hard-safe-A + unsafe-B #1/123: ok | ok | ok | [ 0.000000] soft-safe-A + unsafe-B #1/123: ok | ok | ok | Link: http://lkml.kernel.org/r/20180730222423.196630-4-joel@joelfernandes.org Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Reviewed-by: Namhyung Kim <namhyung@kernel.org> Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-30tracing: kprobes: Prohibit probing on notrace functionMasami Hiramatsu1-0/+20
Prohibit kprobe-events probing on notrace functions. Since probing on a notrace function can cause a recursive event call. In most cases those are just skipped, but in some cases it falls into an infinite recursive call. This protection can be disabled by the kconfig CONFIG_KPROBE_EVENTS_ON_NOTRACE=y, but it is highly recommended to keep it "n" for normal kernel builds. Note that this is only available if "kprobes on ftrace" has been implemented on the target arch and CONFIG_KPROBES_ON_FTRACE=y. Link: http://lkml.kernel.org/r/153294601436.32740.10557881188933661239.stgit@devbox Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Tested-by: Francis Deslauriers <francis.deslauriers@efficios.com> [ Slight grammar and spelling fixes ] Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-26doc: tracing: Fix a typo of trace_statMasami Hiramatsu1-1/+1
The name of the directory for per-cpu function statistics is trace_stat, not trace_stats. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-07-26lib: Add module for testing preemptoff/irqsoff latency tracersJoel Fernandes (Google)1-0/+15
Here we introduce a test module for introducing a long preempt or irq disable delay in the kernel which the preemptoff or irqsoff tracers can detect. This module is to be used only for test purposes and is default disabled. Following is the expected output (only briefly shown) that can be parsed to verify that the tracers are working correctly. We will use this from the kselftests in future patches. For the preemptoff tracer: echo preemptoff > /d/tracing/current_tracer sleep 1 insmod ./preemptirq_delay_test.ko test_mode=preempt delay=500000 sleep 1 bash-4.3# cat /d/tracing/trace preempt -1066 2...2 0us@: preemptirq_delay_run <-preemptirq_delay_run preempt -1066 2...2 500002us : preemptirq_delay_run <-preemptirq_delay_run preempt -1066 2...2 500004us : tracer_preempt_on <-preemptirq_delay_run preempt -1066 2...2 500012us : <stack trace> => kthread => ret_from_fork For the irqsoff tracer: echo irqsoff > /d/tracing/current_tracer sleep 1 insmod ./preemptirq_delay_test.ko test_mode=irq delay=500000 sleep 1 bash-4.3# cat /d/tracing/trace irq dis -1069 1d..1 0us@: preemptirq_delay_run irq dis -1069 1d..1 500001us : preemptirq_delay_run irq dis -1069 1d..1 500002us : tracer_hardirqs_on <-preemptirq_delay_run irq dis -1069 1d..1 500005us : <stack trace> => ret_from_fork Link: http://lkml.kernel.org/r/20180712213611.GA8743@joelaf.mtv.corp.google.com Cc: Boqun Feng <boqun.feng@gmail.com> Cc: Byungchul Park <byungchul.park@lge.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: Julia Cartwright <julia@ni.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paul McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Shuah Khan <shuah@kernel.org> Cc: Thomas Glexiner <tglx@linutronix.de> Cc: Todd Kjos <tkjos@google.com> Cc: Tom Zanussi <tom.zanussi@linux.intel.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> [ Erick is a co-developer of this commit ] Signed-off-by: Erick Reyes <erickreyes@google.com> Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-07-02docs: histogram.txt: convert it to ReST file formatMauro Carvalho Chehab1-1/+1
Despite being mentioned at Documentation/trace/ftrace.rst as a rst file, this file was still a text one, with several issues. Convert it to ReST and add it to the trace index: - Mark the document title as such; - Identify and indent the literal blocks; - Use the proper markups for table. Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2018-06-15docs: Fix some broken referencesMauro Carvalho Chehab1-8/+8
As we move stuff around, some doc references are broken. Fix some of them via this script: ./scripts/documentation-file-ref-check --fix Manually checked if the produced result is valid, removing a few false-positives. Acked-by: Takashi Iwai <tiwai@suse.de> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Acked-by: Stephen Boyd <sboyd@kernel.org> Acked-by: Charles Keepax <ckeepax@opensource.wolfsonmicro.com> Acked-by: Mathieu Poirier <mathieu.poirier@linaro.org> Reviewed-by: Coly Li <colyli@suse.de> Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org> Acked-by: Jonathan Corbet <corbet@lwn.net>
2018-05-03tracing: Remove PPC32 wart from config TRACING_SUPPORTMichael Ellerman1-5/+1
config TRACING_SUPPORT has an exception for PPC32, because PPC32 didn't have irqflags tracing support. But that hasn't been true since commit 5d38902c4838 ("powerpc: Add irqtrace support for 32-bit powerpc") (Jun 2009). So remove the exception for PPC32 and the comment. Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2018-03-10tracing: Add inter-event blurb to HIST_TRIGGERS config optionTom Zanussi1-1/+4
So that users know that inter-event tracing is supported as part of the HIST_TRIGGERS option, include text to that effect in the help text. Link: http://lkml.kernel.org/r/a38e24231d8d980be636b56d35814570acfd167a.1516069914.git.tom.zanussi@linux.intel.com Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-01-17Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller1-1/+1
Overlapping changes all over. The mini-qdisc bits were a little bit tricky, however. Signed-off-by: David S. Miller <davem@davemloft.net>
2018-01-15tracing: Prevent PROFILE_ALL_BRANCHES when FORTIFY_SOURCE=yRandy Dunlap1-1/+1
I regularly get 50 MB - 60 MB files during kernel randconfig builds. These large files mostly contain (many repeats of; e.g., 124,594): In file included from ../include/linux/string.h:6:0, from ../include/linux/uuid.h:20, from ../include/linux/mod_devicetable.h:13, from ../scripts/mod/devicetable-offsets.c:3: ../include/linux/compiler.h:64:4: warning: '______f' is static but declared in inline function 'strcpy' which is not static [enabled by default] ______f = { \ ^ ../include/linux/compiler.h:56:23: note: in expansion of macro '__trace_if' ^ ../include/linux/string.h:425:2: note: in expansion of macro 'if' if (p_size == (size_t)-1 && q_size == (size_t)-1) ^ This only happens when CONFIG_FORTIFY_SOURCE=y and CONFIG_PROFILE_ALL_BRANCHES=y, so prevent PROFILE_ALL_BRANCHES if FORTIFY_SOURCE=y. Link: http://lkml.kernel.org/r/9199446b-a141-c0c3-9678-a3f9107f2750@infradead.org Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2018-01-12error-injection: Separate error-injection from kprobeMasami Hiramatsu1-1/+1
Since error-injection framework is not limited to be used by kprobes, nor bpf. Other kernel subsystems can use it freely for checking safeness of error-injection, e.g. livepatch, ftrace etc. So this separate error-injection framework from kprobes. Some differences has been made: - "kprobe" word is removed from any APIs/structures. - BPF_ALLOW_ERROR_INJECTION() is renamed to ALLOW_ERROR_INJECTION() since it is not limited for BPF too. - CONFIG_FUNCTION_ERROR_INJECTION is the config item of this feature. It is automatically enabled if the arch supports error injection feature for kprobe or ftrace etc. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Reviewed-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2018-01-12tracing/kprobe: bpf: Check error injectable event is on function entryMasami Hiramatsu1-2/+0
Check whether error injectable event is on function entry or not. Currently it checks the event is ftrace-based kprobes or not, but that is wrong. It should check if the event is on the entry of target function. Since error injection will override a function to just return with modified return value, that operation must be done before the target function starts making stackframe. As a side effect, bpf error injection is no need to depend on function-tracer. It can work with sw-breakpoint based kprobe events too. Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Reviewed-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2017-12-18Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-nextDavid S. Miller1-0/+11
Daniel Borkmann says: ==================== pull-request: bpf-next 2017-12-18 The following pull-request contains BPF updates for your *net-next* tree. The main changes are: 1) Allow arbitrary function calls from one BPF function to another BPF function. As of today when writing BPF programs, __always_inline had to be used in the BPF C programs for all functions, unnecessarily causing LLVM to inflate code size. Handle this more naturally with support for BPF to BPF calls such that this __always_inline restriction can be overcome. As a result, it allows for better optimized code and finally enables to introduce core BPF libraries in the future that can be reused out of different projects. x86 and arm64 JIT support was added as well, from Alexei. 2) Add infrastructure for tagging functions as error injectable and allow for BPF to return arbitrary error values when BPF is attached via kprobes on those. This way of injecting errors generically eases testing and debugging without having to recompile or restart the kernel. Tags for opting-in for this facility are added with BPF_ALLOW_ERROR_INJECTION(), from Josef. 3) For BPF offload via nfp JIT, add support for bpf_xdp_adjust_head() helper call for XDP programs. First part of this work adds handling of BPF capabilities included in the firmware, and the later patches add support to the nfp verifier part and JIT as well as some small optimizations, from Jakub. 4) The bpftool now also gets support for basic cgroup BPF operations such as attaching, detaching and listing current BPF programs. As a requirement for the attach part, bpftool can now also load object files through 'bpftool prog load'. This reuses libbpf which we have in the kernel tree as well. bpftool-cgroup man page is added along with it, from Roman. 5) Back then commit e87c6bc3852b ("bpf: permit multiple bpf attachments for a single perf event") added support for attaching multiple BPF programs to a single perf event. Given they are configured through perf's ioctl() interface, the interface has been extended with a PERF_EVENT_IOC_QUERY_BPF command in this work in order to return an array of one or multiple BPF prog ids that are currently attached, from Yonghong. 6) Various minor fixes and cleanups to the bpftool's Makefile as well as a new 'uninstall' and 'doc-uninstall' target for removing bpftool itself or prior installed documentation related to it, from Quentin. 7) Add CONFIG_CGROUP_BPF=y to the BPF kernel selftest config file which is required for the test_dev_cgroup test case to run, from Naresh. 8) Fix reporting of XDP prog_flags for nfp driver, from Jakub. 9) Fix libbpf's exit code from the Makefile when libelf was not found in the system, also from Jakub. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2017-12-12bpf: add a bpf_override_function helperJosef Bacik1-0/+11
Error injection is sloppy and very ad-hoc. BPF could fill this niche perfectly with it's kprobe functionality. We could make sure errors are only triggered in specific call chains that we care about with very specific situations. Accomplish this with the bpf_override_funciton helper. This will modify the probe'd callers return value to the specified value and set the PC to an override function that simply returns, bypassing the originally probed function. This gives us a nice clean way to implement systematic error injection for all of our code paths. Acked-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Josef Bacik <jbacik@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2017-12-04tracing: make PREEMPTIRQ_EVENTS depend on TRACINGArnd Bergmann1-0/+1
When CONFIG_TRACING is disabled, the new preemptirq events tracer produces a build failure: In file included from kernel/trace/trace_irqsoff.c:17:0: kernel/trace/trace.h: In function 'trace_test_and_set_recursion': kernel/trace/trace.h:542:28: error: 'struct task_struct' has no member named 'trace_recursion' Adding an explicit dependency avoids the broken configuration. Link: http://lkml.kernel.org/r/20171103104031.270375-1-arnd@arndb.de Fixes: d59158162e03 ("tracing: Add support for preempt and irq enable/disable events") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2017-11-17Merge tag 'trace-v4.15' of ↵Linus Torvalds1-0/+11
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from - allow module init functions to be traced - clean up some unused or not used by config events (saves space) - clean up of trace histogram code - add support for preempt and interrupt enabled/disable events - other various clean ups * tag 'trace-v4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (30 commits) tracing, thermal: Hide cpu cooling trace events when not in use tracing, thermal: Hide devfreq trace events when not in use ftrace: Kill FTRACE_OPS_FL_PER_CPU perf/ftrace: Small cleanup perf/ftrace: Fix function trace events perf/ftrace: Revert ("perf/ftrace: Fix double traces of perf on ftrace:function") tracing, dma-buf: Remove unused trace event dma_fence_annotate_wait_on tracing, memcg, vmscan: Hide trace events when not in use tracing/xen: Hide events that are not used when X86_PAE is not defined tracing: mark trace_test_buffer as __maybe_unused printk: Remove superfluous memory barriers from printk_safe ftrace: Clear hashes of stale ips of init memory tracing: Add support for preempt and irq enable/disable events tracing: Prepare to add preempt and irq trace events ftrace/kallsyms: Have /proc/kallsyms show saved mod init functions ftrace: Add freeing algorithm to free ftrace_mod_maps ftrace: Save module init functions kallsyms symbols for tracing ftrace: Allow module init functions to be traced ftrace: Add a ftrace_free_mem() function for modules to use tracing: Reimplement log2 ...