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2020-06-15ftrace: Add perf ksymbol events for ftrace trampolinesAdrian Hunter
Symbols are needed for tools to describe instruction addresses. Pages allocated for ftrace's purposes need symbols to be created for them. Add such symbols to be visible via perf ksymbol events. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20200512121922.8997-8-adrian.hunter@intel.com
2020-06-15ftrace: Add symbols for ftrace trampolinesAdrian Hunter
Symbols are needed for tools to describe instruction addresses. Pages allocated for ftrace's purposes need symbols to be created for them. Add such symbols to be visible via /proc/kallsyms. Example on x86 with CONFIG_DYNAMIC_FTRACE=y # echo function > /sys/kernel/debug/tracing/current_tracer # cat /proc/kallsyms | grep '\[__builtin__ftrace\]' ffffffffc0238000 t ftrace_trampoline [__builtin__ftrace] Note: This patch adds "__builtin__ftrace" as a module name in /proc/kallsyms for symbols for pages allocated for ftrace's purposes, even though "__builtin__ftrace" is not a module. Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://lkml.kernel.org/r/20200512121922.8997-7-adrian.hunter@intel.com
2020-06-09Merge tag 'trace-v5.8' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: "No new features this release. Mostly clean ups, restructuring and documentation. - Have ftrace_bug() show ftrace errors before the WARN, as the WARN will reboot the box before the error messages are printed if panic_on_warn is set. - Have traceoff_on_warn disable tracing sooner (before prints) - Write a message to the trace buffer that its being disabled when disable_trace_on_warning() is set. - Separate out synthetic events from histogram code to let it be used by other parts of the kernel. - More documentation on histogram design. - Other small fixes and clean ups" * tag 'trace-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: tracing: Remove obsolete PREEMPTIRQ_EVENTS kconfig option tracing/doc: Fix ascii-art in histogram-design.rst tracing: Add a trace print when traceoff_on_warning is triggered ftrace,bug: Improve traceoff_on_warn selftests/ftrace: Distinguish between hist and synthetic event checks tracing: Move synthetic events to a separate file tracing: Fix events.rst section numbering tracing/doc: Fix typos in histogram-design.rst tracing: Add hist_debug trace event files for histogram debugging tracing: Add histogram-design document tracing: Check state.disabled in synth event trace functions tracing/probe: reverse arguments to list_add tools/bootconfig: Add a summary of test cases and return error ftrace: show debugging information when panic_on_warn set
2020-06-09kallsyms/printk: add loglvl to print_ip_sym()Dmitry Safonov
Patch series "Add log level to show_stack()", v3. Add log level argument to show_stack(). Done in three stages: 1. Introducing show_stack_loglvl() for every architecture 2. Migrating old users with an explicit log level 3. Renaming show_stack_loglvl() into show_stack() Justification: - It's a design mistake to move a business-logic decision into platform realization detail. - I have currently two patches sets that would benefit from this work: Removing console_loglevel jumps in sysrq driver [1] Hung task warning before panic [2] - suggested by Tetsuo (but he probably didn't realise what it would involve). - While doing (1), (2) the backtraces were adjusted to headers and other messages for each situation - so there won't be a situation when the backtrace is printed, but the headers are missing because they have lesser log level (or the reverse). - As the result in (2) plays with console_loglevel for kdb are removed. The least important for upstream, but maybe still worth to note that every company I've worked in so far had an off-list patch to print backtrace with the needed log level (but only for the architecture they cared about). If you have other ideas how you will benefit from show_stack() with a log level - please, reply to this cover letter. See also discussion on v1: https://lore.kernel.org/linux-riscv/20191106083538.z5nlpuf64cigxigh@pathway.suse.cz/ This patch (of 50): print_ip_sym() needs to have a log level parameter to comply with other parts being printed. Otherwise, half of the expected backtrace would be printed and other may be missing with some logging level. The following callee(s) are using now the adjusted log level: - microblaze/unwind: the same level as headers & userspace unwind. Note that pr_debug()'s there are for debugging the unwinder itself. - nds32/traps: symbol addresses are printed with the same log level as backtrace headers. - lockdep: ip for locking issues is printed with the same log level as other part of the warning. - sched: ip where preemption was disabled is printed as error like the rest part of the message. - ftrace: bug reports are now consistent in the log level being used. Signed-off-by: Dmitry Safonov <dima@arista.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: Albert Ou <aou@eecs.berkeley.edu> Cc: Ben Segall <bsegall@google.com> Cc: Dietmar Eggemann <dietmar.eggemann@arm.com> Cc: Greentime Hu <green.hu@gmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Hogan <jhogan@kernel.org> Cc: Juri Lelli <juri.lelli@redhat.com> Cc: Mel Gorman <mgorman@suse.de> Cc: Michal Simek <monstr@monstr.eu> Cc: Palmer Dabbelt <palmer@dabbelt.com> Cc: Paul Burton <paulburton@kernel.org> Cc: Paul Walmsley <paul.walmsley@sifive.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vincent Chen <deanbo422@gmail.com> Cc: Vincent Guittot <vincent.guittot@linaro.org> Cc: Will Deacon <will@kernel.org> Cc: Dmitry Safonov <0x7f454c46@gmail.com> Cc: Dmitry Safonov <dima@arista.com> Cc: Jiri Slaby <jslaby@suse.com> Cc: Petr Mladek <pmladek@suse.com> Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru> Cc: Matt Turner <mattst88@gmail.com> Cc: Richard Henderson <rth@twiddle.net> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Russell King <linux@armlinux.org.uk> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Aurelien Jacquiot <jacquiot.aurelien@gmail.com> Cc: Mark Salter <msalter@redhat.com> Cc: Guo Ren <guoren@kernel.org> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Cc: Brian Cain <bcain@codeaurora.org> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Tony Luck <tony.luck@intel.com> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Ley Foon Tan <lftan@altera.com> Cc: Jonas Bonn <jonas@southpole.se> Cc: Stafford Horne <shorne@gmail.com> Cc: Stefan Kristiansson <stefan.kristiansson@saunalahti.fi> Cc: Helge Deller <deller@gmx.de> Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Paul Mackerras <paulus@samba.org> Cc: Christian Borntraeger <borntraeger@de.ibm.com> Cc: Heiko Carstens <heiko.carstens@de.ibm.com> Cc: Vasily Gorbik <gor@linux.ibm.com> Cc: Rich Felker <dalias@libc.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Anton Ivanov <anton.ivanov@cambridgegreys.com> Cc: Jeff Dike <jdike@addtoit.com> Cc: Richard Weinberger <richard@nod.at> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Borislav Petkov <bp@alien8.de> Cc: "H. Peter Anvin" <hpa@zytor.com> Cc: Chris Zankel <chris@zankel.net> Cc: Max Filippov <jcmvbkbc@gmail.com> Cc: Len Brown <len.brown@intel.com> Cc: Pavel Machek <pavel@ucw.cz> Cc: "Rafael J. Wysocki" <rjw@rjwysocki.net> Cc: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com> Cc: Daniel Thompson <daniel.thompson@linaro.org> Cc: Douglas Anderson <dianders@chromium.org> Cc: Jason Wessel <jason.wessel@windriver.com> Link: http://lkml.kernel.org/r/20200418201944.482088-2-dima@arista.com Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-05-19ftrace: show debugging information when panic_on_warn setCheng Jian
When an anomaly is detected in the function call modification code, ftrace_bug() is called to disable function tracing as well as give some warn and information that may help debug the problem. But currently, we call FTRACE_WARN_ON_ONCE() first in ftrace_bug(), so when panic_on_warn is set, we can't see the debugging information here. Call FTRACE_WARN_ON_ONCE() at the end of ftrace_bug() to ensure that the debugging information is displayed first. after this patch, the dmesg looks like: ------------[ ftrace bug ]------------ ftrace failed to modify [<ffff800010081004>] bcm2835_handle_irq+0x4/0x58 actual: 1f:20:03:d5 Setting ftrace call site to call ftrace function ftrace record flags: 80000001 (1) expected tramp: ffff80001009d6f0 ------------[ cut here ]------------ WARNING: CPU: 2 PID: 1635 at kernel/trace/ftrace.c:2078 ftrace_bug+0x204/0x238 Kernel panic - not syncing: panic_on_warn set ... CPU: 2 PID: 1635 Comm: sh Not tainted 5.7.0-rc5-00033-gb922183867f5 #14 Hardware name: linux,dummy-virt (DT) Call trace: dump_backtrace+0x0/0x1b0 show_stack+0x20/0x30 dump_stack+0xc0/0x10c panic+0x16c/0x368 __warn+0x120/0x160 report_bug+0xc8/0x160 bug_handler+0x28/0x98 brk_handler+0x70/0xd0 do_debug_exception+0xcc/0x1ac el1_sync_handler+0xe4/0x120 el1_sync+0x7c/0x100 ftrace_bug+0x204/0x238 Link: https://lkml.kernel.org/r/20200515100828.7091-1-cj.chengjian@huawei.com Signed-off-by: Cheng Jian <cj.chengjian@huawei.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-05-19Merge tag 'noinstr-lds-2020-05-19' into core/rcuThomas Gleixner
Get the noinstr section and annotation markers to base the RCU parts on.
2020-04-27ftrace: Use synchronize_rcu_tasks_rude() instead of ftrace_sync()Paul E. McKenney
This commit replaces the schedule_on_each_cpu(ftrace_sync) instances with synchronize_rcu_tasks_rude(). Suggested-by: Steven Rostedt <rostedt@goodmis.org> Cc: Ingo Molnar <mingo@redhat.com> [ paulmck: Make Kconfig adjustments noted by kbuild test robot. ] Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
2020-04-22ftrace: Fix memory leak caused by not freeing entry in ↵Steven Rostedt (VMware)
unregister_ftrace_direct() kmemleak reported the following: unreferenced object 0xffff90d47127a920 (size 32): comm "modprobe", pid 1766, jiffies 4294792031 (age 162.568s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 22 01 00 00 00 00 ad de ........"....... 00 78 12 a7 ff ff ff ff 00 00 b6 c0 ff ff ff ff .x.............. backtrace: [<00000000bb79e72e>] register_ftrace_direct+0xcb/0x3a0 [<00000000295e4f79>] do_one_initcall+0x72/0x340 [<00000000873ead18>] do_init_module+0x5a/0x220 [<00000000974d9de5>] load_module+0x2235/0x2550 [<0000000059c3d6ce>] __do_sys_finit_module+0xc0/0x120 [<000000005a8611b4>] do_syscall_64+0x60/0x230 [<00000000a0cdc49e>] entry_SYSCALL_64_after_hwframe+0x49/0xb3 The entry used to save the direct descriptor needs to be freed when unregistering. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-04-05Merge tag 'trace-v5.7' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: "New tracing features: - The ring buffer is no longer disabled when reading the trace file. The trace_pipe file was made to be used for live tracing and reading as it acted like the normal producer/consumer. As the trace file would not consume the data, the easy way of handling it was to just disable writes to the ring buffer. This came to a surprise to the BPF folks who complained about lost events due to reading. This is no longer an issue. If someone wants to keep the old disabling there's a new option "pause-on-trace" that can be set. - New set_ftrace_notrace_pid file. PIDs in this file will not be traced by the function tracer. Similar to set_ftrace_pid, which makes the function tracer only trace those tasks with PIDs in the file, the set_ftrace_notrace_pid does the reverse. - New set_event_notrace_pid file. PIDs in this file will cause events not to be traced if triggered by a task with a matching PID. Similar to the set_event_pid file but will not be traced. Note, sched_waking and sched_switch events may still be traced if one of the tasks referenced by those events contains a PID that is allowed to be traced. Tracing related features: - New bootconfig option, that is attached to the initrd file. If bootconfig is on the command line, then the initrd file is searched looking for a bootconfig appended at the end. - New GPU tracepoint infrastructure to help the gfx drivers to get off debugfs (acked by Greg Kroah-Hartman) And other minor updates and fixes" * tag 'trace-v5.7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (27 commits) tracing: Do not allocate buffer in trace_find_next_entry() in atomic tracing: Add documentation on set_ftrace_notrace_pid and set_event_notrace_pid selftests/ftrace: Add test to test new set_event_notrace_pid file selftests/ftrace: Add test to test new set_ftrace_notrace_pid file tracing: Create set_event_notrace_pid to not trace tasks ftrace: Create set_ftrace_notrace_pid to not trace tasks ftrace: Make function trace pid filtering a bit more exact ftrace/kprobe: Show the maxactive number on kprobe_events tracing: Have the document reflect that the trace file keeps tracing enabled ring-buffer/tracing: Have iterator acknowledge dropped events tracing: Do not disable tracing when reading the trace file ring-buffer: Do not disable recording when there is an iterator ring-buffer: Make resize disable per cpu buffer instead of total buffer ring-buffer: Optimize rb_iter_head_event() ring-buffer: Do not die if rb_iter_peek() fails more than thrice ring-buffer: Have rb_iter_head_event() handle concurrent writer ring-buffer: Add page_stamp to iterator for synchronization ring-buffer: Rename ring_buffer_read() to read_buffer_iter_advance() ring-buffer: Have ring_buffer_empty() not depend on tracing stopped tracing: Save off entry when peeking at next entry ...
2020-03-27tracing: Create set_event_notrace_pid to not trace tasksSteven Rostedt (VMware)
There's currently a way to select a task that should only have its events traced, but there's no way to select a task not to have itsevents traced. Add a set_event_notrace_pid file that acts the same as set_event_pid (and is also affected by event-fork), but the task pids in this file will not be traced even if they are listed in the set_event_pid file. This makes it easy for tools like trace-cmd to "hide" itself from beint traced by events when it is recording other tasks. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-03-27ftrace: Create set_ftrace_notrace_pid to not trace tasksSteven Rostedt (VMware)
There's currently a way to select a task that should only be traced by functions, but there's no way to select a task not to be traced by the function tracer. Add a set_ftrace_notrace_pid file that acts the same as set_ftrace_pid (and is also affected by function-fork), but the task pids in this file will not be traced even if they are listed in the set_ftrace_pid file. This makes it easy for tools like trace-cmd to "hide" itself from the function tracer when it is recording other tasks. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-03-27ftrace: Make function trace pid filtering a bit more exactSteven Rostedt (VMware)
The set_ftrace_pid file is used to filter function tracing to only trace tasks that are listed in that file. Instead of testing the pids listed in that file (it's a bitmask) at each function trace event, the logic is done via a sched_switch hook. A flag is set when the next task to run is in the list of pids in the set_ftrace_pid file. But the sched_switch hook is not at the exact location of when the task switches, and the flag gets set before the task to be traced actually runs. This leaves a residue of traced functions that do not belong to the pid that should be filtered on. By changing the logic slightly, where instead of having a boolean flag to test, record the pid that should be traced, with special values for not to trace and always trace. Then at each function call, a check will be made to see if the function should be ignored, or if the current pid matches the function that should be traced, and only trace if it matches (or if it has the special value to always trace). Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-03-11ftrace: Return the first found result in lookup_rec()Artem Savkov
It appears that ip ranges can overlap so. In that case lookup_rec() returns whatever results it got last even if it found nothing in last searched page. This breaks an obscure livepatch late module patching usecase: - load livepatch - load the patched module - unload livepatch - try to load livepatch again To fix this return from lookup_rec() as soon as it found the record containing searched-for ip. This used to be this way prior lookup_rec() introduction. Link: http://lkml.kernel.org/r/20200306174317.21699-1-asavkov@redhat.com Cc: stable@vger.kernel.org Fixes: 7e16f581a817 ("ftrace: Separate out functionality from ftrace_location_range()") Signed-off-by: Artem Savkov <asavkov@redhat.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-02-05ftrace: Protect ftrace_graph_hash with ftrace_syncSteven Rostedt (VMware)
As function_graph tracer can run when RCU is not "watching", it can not be protected by synchronize_rcu() it requires running a task on each CPU before it can be freed. Calling schedule_on_each_cpu(ftrace_sync) needs to be used. Link: https://lore.kernel.org/r/20200205131110.GT2935@paulmck-ThinkPad-P72 Cc: stable@vger.kernel.org Fixes: b9b0c831bed26 ("ftrace: Convert graph filter to use hash tables") Reported-by: "Paul E. McKenney" <paulmck@kernel.org> Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-02-05tracing: Annotate ftrace_graph_notrace_hash pointer with __rcuAmol Grover
Fix following instances of sparse error kernel/trace/ftrace.c:5667:29: error: incompatible types in comparison kernel/trace/ftrace.c:5813:21: error: incompatible types in comparison kernel/trace/ftrace.c:5868:36: error: incompatible types in comparison kernel/trace/ftrace.c:5870:25: error: incompatible types in comparison Use rcu_dereference_protected to dereference the newly annotated pointer. Link: http://lkml.kernel.org/r/20200205055701.30195-1-frextrite@gmail.com Signed-off-by: Amol Grover <frextrite@gmail.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-02-05tracing: Annotate ftrace_graph_hash pointer with __rcuAmol Grover
Fix following instances of sparse error kernel/trace/ftrace.c:5664:29: error: incompatible types in comparison kernel/trace/ftrace.c:5785:21: error: incompatible types in comparison kernel/trace/ftrace.c:5864:36: error: incompatible types in comparison kernel/trace/ftrace.c:5866:25: error: incompatible types in comparison Use rcu_dereference_protected to access the __rcu annotated pointer. Link: http://lkml.kernel.org/r/20200201072703.17330-1-frextrite@gmail.com Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Amol Grover <frextrite@gmail.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-01-30ftrace: fpid_next() should increase position indexVasily Averin
if seq_file .next fuction does not change position index, read after some lseek can generate unexpected output. Without patch: # dd bs=4 skip=1 if=/sys/kernel/tracing/set_ftrace_pid dd: /sys/kernel/tracing/set_ftrace_pid: cannot skip to specified offset id no pid 2+1 records in 2+1 records out 10 bytes copied, 0.000213285 s, 46.9 kB/s Notice the "id" followed by "no pid". With the patch: # dd bs=4 skip=1 if=/sys/kernel/tracing/set_ftrace_pid dd: /sys/kernel/tracing/set_ftrace_pid: cannot skip to specified offset id 0+1 records in 0+1 records out 3 bytes copied, 0.000202112 s, 14.8 kB/s Notice that it only prints "id" and not the "no pid" afterward. Link: http://lkml.kernel.org/r/4f87c6ad-f114-30bb-8506-c32274ce2992@virtuozzo.com https://bugzilla.kernel.org/show_bug.cgi?id=206283 Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-01-25tracing: Use pr_err() instead of WARN() for memory failuresSteven Rostedt (VMware)
As warnings can trigger panics, especially when "panic_on_warn" is set, memory failure warnings can cause panics and fail fuzz testers that are stressing memory. Create a MEM_FAIL() macro to use instead of WARN() in the tracing code (perhaps this should be a kernel wide macro?), and use that for memory failure issues. This should stop failing fuzz tests due to warnings. Link: https://lore.kernel.org/r/CACT4Y+ZP-7np20GVRu3p+eZys9GPtbu+JpfV+HtsufAzvTgJrg@mail.gmail.com Suggested-by: Dmitry Vyukov <dvyukov@google.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-01-21ftrace: Remove NR_TO_INIT macroAlex Shi
This macro isn't used from commit cb7be3b2fc2c ("ftrace: remove daemon"). So no needs to keep it. Link: http://lkml.kernel.org/r/1579586063-44984-1-git-send-email-alex.shi@linux.alibaba.com Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-01-21ftrace: Remove abandoned macrosAlex Shi
These 2 macros aren't used from commit eee8ded131f1 ("ftrace: Have the function probes call their own function"), so remove them. Link: http://lkml.kernel.org/r/1579585807-43316-1-git-send-email-alex.shi@linux.alibaba.com Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-01-13tracing: Rename trace_buffer to array_bufferSteven Rostedt (VMware)
As we are working to remove the generic "ring_buffer" name that is used by both tracing and perf, the ring_buffer name for tracing will be renamed to trace_buffer, and perf's ring buffer will be renamed to perf_buffer. As there already exists a trace_buffer that is used by the trace_arrays, it needs to be first renamed to array_buffer. Link: https://lore.kernel.org/r/20191213153553.GE20583@krava Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2020-01-02ftrace: Avoid potential division by zero in function profilerWen Yang
The ftrace_profile->counter is unsigned long and do_div truncates it to 32 bits, which means it can test non-zero and be truncated to zero for division. Fix this issue by using div64_ul() instead. Link: http://lkml.kernel.org/r/20200103030248.14516-1-wenyang@linux.alibaba.com Cc: stable@vger.kernel.org Fixes: e330b3bcd8319 ("tracing: Show sample std dev in function profiling") Fixes: 34886c8bc590f ("tracing: add average time in function to function profiler") Signed-off-by: Wen Yang <wenyang@linux.alibaba.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-12-11Merge tag 'trace-v5.5-3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing fixes from Steven Rostedt: - Remove code I accidentally applied when doing a minor fix up to a patch, and then using "git commit -a --amend", which pulled in some other changes I was playing with. - Remove an used variable in trace_events_inject code - Fix function graph tracer when it traces a ftrace direct function. It will now ignore tracing a function that has a ftrace direct tramploine attached. This is needed for eBPF to use the ftrace direct code. * tag 'trace-v5.5-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: ftrace: Fix function_graph tracer interaction with BPF trampoline tracing: remove set but not used variable 'buffer' module: Remove accidental change of module_enable_x()
2019-12-10ftrace: Fix function_graph tracer interaction with BPF trampolineAlexei Starovoitov
Depending on type of BPF programs served by BPF trampoline it can call original function. In such case the trampoline will skip one stack frame while returning. That will confuse function_graph tracer and will cause crashes with bad RIP. Teach graph tracer to skip functions that have BPF trampoline attached. Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-27Merge tag 'trace-v5.5' of ↵Linus Torvalds
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 ...
2019-11-18ftrace: Add a helper function to modify_ftrace_direct() to allow arch ↵Steven Rostedt (VMware)
optimization If a direct ftrace callback is at a location that does not have any other ftrace helpers attached to it, it is possible to simply just change the text to call the new caller (if the architecture supports it). But this requires special architecture code. Currently, modify_ftrace_direct() uses a trick to add a stub ftrace callback to the location forcing it to call the ftrace iterator. Then it can change the direct helper to call the new function in C, and then remove the stub. Removing the stub will have the location now call the new location that the direct helper is using. The new helper function does the registering the stub trick, but is a weak function, allowing an architecture to override it to do something a bit more direct. Link: https://lore.kernel.org/r/20191115215125.mbqv7taqnx376yed@ast-mbp.dhcp.thefacebook.com Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-15ftrace: Add helper find_direct_entry() to consolidate codeSteven Rostedt (VMware)
Both unregister_ftrace_direct() and modify_ftrace_direct() needs to normalize the ip passed in to match the rec->ip, as it is acceptable to have the ip on the ftrace call site but not the start. There are also common validity checks with the record found by the ip, these should be done for both unregister_ftrace_direct() and modify_ftrace_direct(). Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-15ftrace: Add another check for match in register_ftrace_direct()Steven Rostedt (VMware)
As an instruction pointer passed into register_ftrace_direct() may just exist on the ftrace call site, but may not be the start of the call site itself, register_ftrace_direct() still needs to update test if a direct call exists on the normalized site, as only one direct call is allowed at any one time. Fixes: 763e34e74bb7d ("ftrace: Add register_ftrace_direct()") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-15ftrace: Fix accounting bug with direct->count in register_ftrace_direct()Steven Rostedt (VMware)
The direct->count wasn't being updated properly, where it only was updated when the first entry was added, but should be updated every time. Fixes: 013bf0da04748 ("ftrace: Add ftrace_find_direct_func()") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-14ftrace: Add modify_ftrace_direct()Steven Rostedt (VMware)
Add a new function modify_ftrace_direct() that will allow a user to update an existing direct caller to a new trampoline, without missing hits due to unregistering one and then adding another. Link: https://lore.kernel.org/r/20191109022907.6zzo6orhxpt5n2sv@ast-mbp.dhcp.thefacebook.com Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-14tracing: Use generic type for comparator functionAndy Shevchenko
Comparator function type, cmp_func_t, is defined in the types.h, use it in the code. Link: http://lkml.kernel.org/r/20191007135656.37734-3-andriy.shevchenko@linux.intel.com Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13ftrace: Add information on number of page groups allocatedSteven Rostedt (VMware)
Looking for ways to shrink the size of the dyn_ftrace structure, knowing the information about how many pages and the number of groups of those pages, is useful in working out the best ways to save on memory. This adds one info print on how many groups of pages were used to allocate the ftrace dyn_ftrace structures, and also shows the number of pages and groups in the dyn_ftrace_total_info (which is used for debugging). Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13ftrace/x86: Add a counter to test function_graph with directSteven Rostedt (VMware)
As testing for direct calls from the function graph tracer adds a little overhead (which is a lot when tracing every function), add a counter that can be used to test if function_graph tracer needs to test for a direct caller or not. It would have been nicer if we could use a static branch, but the static branch logic fails when used within the function graph tracer trampoline. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13ftrace: Add ftrace_find_direct_func()Steven Rostedt (VMware)
As function_graph tracer modifies the return address to insert a trampoline to trace the return of a function, it must be aware of a direct caller, as when it gets called, the function's return address may not be at on the stack where it expects. It may have to see if that return address points to the a direct caller and adjust if it is. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-13ftrace: Add register_ftrace_direct()Steven Rostedt (VMware)
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>
2019-11-08ftrace: Separate out functionality from ftrace_location_range()Steven Rostedt (VMware)
Create a new function called lookup_rec() from the functionality of ftrace_location_range(). The difference between lookup_rec() is that it returns the record that it finds, where as ftrace_location_range() returns only if it found a match or not. The lookup_rec() is static, and can be used for new functionality where ftrace needs to find a record of a specific address. Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-11-08ftrace: Separate out the copying of a ftrace_hash from __ftrace_hash_move()Steven Rostedt (VMware)
Most of the functionality of __ftrace_hash_move() can be reused, but not all of it. That is, __ftrace_hash_move() is used to simply make a new hash from an existing one, using the same size as the original. Creating a dup_hash(), where we can specify a new size will be useful when we want to create a hash with a default size, or simply copy the old one. Signed-off-by: Steven Rostedt (VMWare) <rostedt@goodmis.org>
2019-11-06ftrace: add ftrace_init_nop()Mark Rutland
Architectures may need to perform special initialization of ftrace callsites, and today they do so by special-casing ftrace_make_nop() when the expected branch address is MCOUNT_ADDR. In some cases (e.g. for patchable-function-entry), we don't have an mcount-like symbol and don't want a synthetic MCOUNT_ADDR, but we may need to perform some initialization of callsites. To make it possible to separate initialization from runtime modification, and to handle cases without an mcount-like symbol, this patch adds an optional ftrace_init_nop() function that architectures can implement, which does not pass a branch address. Where an architecture does not provide ftrace_init_nop(), we will fall back to the existing behaviour of calling ftrace_make_nop() with MCOUNT_ADDR. At the same time, ftrace_code_disable() is renamed to ftrace_nop_initialize() to make it clearer that it is intended to intialize a callsite into a disabled state, and is not for disabling a callsite that has been runtime enabled. The kerneldoc description of rec arguments is updated to cover non-mcount callsites. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Amit Daniel Kachhap <amit.kachhap@arm.com> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Miroslav Benes <mbenes@suse.cz> Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org> Reviewed-by: Torsten Duwe <duwe@suse.de> Tested-by: Amit Daniel Kachhap <amit.kachhap@arm.com> Tested-by: Sven Schnelle <svens@stackframe.org> Tested-by: Torsten Duwe <duwe@suse.de> Cc: Ingo Molnar <mingo@redhat.com>
2019-11-04ftrace: Introduce PERMANENT ftrace_ops flagMiroslav Benes
Livepatch uses ftrace for redirection to new patched functions. It means that if ftrace is disabled, all live patched functions are disabled as well. Toggling global 'ftrace_enabled' sysctl thus affect it directly. It is not a problem per se, because only administrator can set sysctl values, but it still may be surprising. Introduce PERMANENT ftrace_ops flag to amend this. If the FTRACE_OPS_FL_PERMANENT is set on any ftrace ops, the tracing cannot be disabled by disabling ftrace_enabled. Equally, a callback with the flag set cannot be registered if ftrace_enabled is disabled. Link: http://lkml.kernel.org/r/20191016113316.13415-2-mbenes@suse.cz Reviewed-by: Petr Mladek <pmladek@suse.com> Reviewed-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com> Signed-off-by: Miroslav Benes <mbenes@suse.cz> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-10-12tracing: Add locked_down checks to the open calls of files created for tracefsSteven Rostedt (VMware)
Added various checks on open tracefs calls to see if tracefs is in lockdown mode, and if so, to return -EPERM. Note, the event format files (which are basically standard on all machines) as well as the enabled_functions file (which shows what is currently being traced) are not lockde down. Perhaps they should be, but it seems counter intuitive to lockdown information to help you know if the system has been modified. Link: http://lkml.kernel.org/r/CAHk-=wj7fGPKUspr579Cii-w_y60PtRaiDgKuxVtBAMK0VNNkA@mail.gmail.com Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-10-12tracing: Add tracing_check_open_get_tr()Steven Rostedt (VMware)
Currently, most files in the tracefs directory test if tracing_disabled is set. If so, it should return -ENODEV. The tracing_disabled is called when tracing is found to be broken. Originally it was done in case the ring buffer was found to be corrupted, and we wanted to prevent reading it from crashing the kernel. But it's also called if a tracing selftest fails on boot. It's a one way switch. That is, once it is triggered, tracing is disabled until reboot. As most tracefs files can also be used by instances in the tracefs directory, they need to be carefully done. Each instance has a trace_array associated to it, and when the instance is removed, the trace_array is freed. But if an instance is opened with a reference to the trace_array, then it requires looking up the trace_array to get its ref counter (as there could be a race with it being deleted and the open itself). Once it is found, a reference is added to prevent the instance from being removed (and the trace_array associated with it freed). Combine the two checks (tracing_disabled and trace_array_get()) into a single helper function. This will also make it easier to add lockdown to tracefs later. Link: http://lkml.kernel.org/r/20191011135458.7399da44@gandalf.local.home Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-10-12ftrace: Get a reference counter for the trace_array on filter filesSteven Rostedt (VMware)
The ftrace set_ftrace_filter and set_ftrace_notrace files are specific for an instance now. They need to take a reference to the instance otherwise there could be a race between accessing the files and deleting the instance. It wasn't until the :mod: caching where these file operations started referencing the trace_array directly. Cc: stable@vger.kernel.org Fixes: 673feb9d76ab3 ("ftrace: Add :mod: caching infrastructure to trace_array") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-09-20Merge tag 'trace-v5.4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace Pull tracing updates from Steven Rostedt: - Addition of multiprobes to kprobe and uprobe events (allows for more than one probe attached to the same location) - Addition of adding immediates to probe parameters - Clean up of the recordmcount.c code. This brings us closer to merging recordmcount into objtool, and reuse code. - Other small clean ups * tag 'trace-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (33 commits) selftests/ftrace: Update kprobe event error testcase tracing/probe: Reject exactly same probe event tracing/probe: Fix to allow user to enable events on unloaded modules selftests/ftrace: Select an existing function in kprobe_eventname test tracing/kprobe: Fix NULL pointer access in trace_porbe_unlink() tracing: Make sure variable reference alias has correct var_ref_idx tracing: Be more clever when dumping hex in __print_hex() ftrace: Simplify ftrace hash lookup code in clear_func_from_hash() tracing: Add "gfp_t" support in synthetic_events tracing: Rename tracing_reset() to tracing_reset_cpu() tracing: Document the stack trace algorithm in the comments tracing/arm64: Have max stack tracer handle the case of return address after data recordmcount: Clarify what cleanup() does recordmcount: Remove redundant cleanup() calls recordmcount: Kernel style formatting recordmcount: Kernel style function signature formatting recordmcount: Rewrite error/success handling selftests/ftrace: Add syntax error test for multiprobe selftests/ftrace: Add syntax error test for immediates selftests/ftrace: Add a testcase for kprobe multiprobe event ...
2019-09-17ftrace: Simplify ftrace hash lookup code in clear_func_from_hash()Changbin Du
Function ftrace_lookup_ip() will check empty hash table. So we don't need extra check outside. Link: http://lkml.kernel.org/r/20190910143336.13472-1-changbin.du@gmail.com Signed-off-by: Changbin Du <changbin.du@gmail.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-09-16Merge branch 'sched-core-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler updates from Ingo Molnar: - MAINTAINERS: Add Mark Rutland as perf submaintainer, Juri Lelli and Vincent Guittot as scheduler submaintainers. Add Dietmar Eggemann, Steven Rostedt, Ben Segall and Mel Gorman as scheduler reviewers. As perf and the scheduler is getting bigger and more complex, document the status quo of current responsibilities and interests, and spread the review pain^H^H^H^H fun via an increase in the Cc: linecount generated by scripts/get_maintainer.pl. :-) - Add another series of patches that brings the -rt (PREEMPT_RT) tree closer to mainline: split the monolithic CONFIG_PREEMPT dependencies into a new CONFIG_PREEMPTION category that will allow the eventual introduction of CONFIG_PREEMPT_RT. Still a few more hundred patches to go though. - Extend the CPU cgroup controller with uclamp.min and uclamp.max to allow the finer shaping of CPU bandwidth usage. - Micro-optimize energy-aware wake-ups from O(CPUS^2) to O(CPUS). - Improve the behavior of high CPU count, high thread count applications running under cpu.cfs_quota_us constraints. - Improve balancing with SCHED_IDLE (SCHED_BATCH) tasks present. - Improve CPU isolation housekeeping CPU allocation NUMA locality. - Fix deadline scheduler bandwidth calculations and logic when cpusets rebuilds the topology, or when it gets deadline-throttled while it's being offlined. - Convert the cpuset_mutex to percpu_rwsem, to allow it to be used from setscheduler() system calls without creating global serialization. Add new synchronization between cpuset topology-changing events and the deadline acceptance tests in setscheduler(), which were broken before. - Rework the active_mm state machine to be less confusing and more optimal. - Rework (simplify) the pick_next_task() slowpath. - Improve load-balancing on AMD EPYC systems. - ... and misc cleanups, smaller fixes and improvements - please see the Git log for more details. * 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (53 commits) sched/psi: Correct overly pessimistic size calculation sched/fair: Speed-up energy-aware wake-ups sched/uclamp: Always use 'enum uclamp_id' for clamp_id values sched/uclamp: Update CPU's refcount on TG's clamp changes sched/uclamp: Use TG's clamps to restrict TASK's clamps sched/uclamp: Propagate system defaults to the root group sched/uclamp: Propagate parent clamps sched/uclamp: Extend CPU's cgroup controller sched/topology: Improve load balancing on AMD EPYC systems arch, ia64: Make NUMA select SMP sched, perf: MAINTAINERS update, add submaintainers and reviewers sched/fair: Use rq_lock/unlock in online_fair_sched_group cpufreq: schedutil: fix equation in comment sched: Rework pick_next_task() slow-path sched: Allow put_prev_task() to drop rq->lock sched/fair: Expose newidle_balance() sched: Add task_struct pointer to sched_class::set_curr_task sched: Rework CPU hotplug task selection sched/{rt,deadline}: Fix set_next_task vs pick_next_task sched: Fix kerneldoc comment for ia64_set_curr_task ...
2019-08-30ftrace: Check for successful allocation of hashNaveen N. Rao
In register_ftrace_function_probe(), we are not checking the return value of alloc_and_copy_ftrace_hash(). The subsequent call to ftrace_match_records() may end up dereferencing the same. Add a check to ensure this doesn't happen. Link: http://lkml.kernel.org/r/26e92574f25ad23e7cafa3cf5f7a819de1832cbe.1562249521.git.naveen.n.rao@linux.vnet.ibm.com Cc: stable@vger.kernel.org Fixes: 1ec3a81a0cf42 ("ftrace: Have each function probe use its own ftrace_ops") Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-08-30ftrace: Check for empty hash and comment the race with registering probesSteven Rostedt (VMware)
The race between adding a function probe and reading the probes that exist is very subtle. It needs a comment. Also, the issue can also happen if the probe has has the EMPTY_HASH as its func_hash. Cc: stable@vger.kernel.org Fixes: 7b60f3d876156 ("ftrace: Dynamically create the probe ftrace_ops for the trace_array") Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-08-30ftrace: Fix NULL pointer dereference in t_probe_next()Naveen N. Rao
LTP testsuite on powerpc results in the below crash: Unable to handle kernel paging request for data at address 0x00000000 Faulting instruction address: 0xc00000000029d800 Oops: Kernel access of bad area, sig: 11 [#1] LE SMP NR_CPUS=2048 NUMA PowerNV ... CPU: 68 PID: 96584 Comm: cat Kdump: loaded Tainted: G W NIP: c00000000029d800 LR: c00000000029dac4 CTR: c0000000001e6ad0 REGS: c0002017fae8ba10 TRAP: 0300 Tainted: G W MSR: 9000000000009033 <SF,HV,EE,ME,IR,DR,RI,LE> CR: 28022422 XER: 20040000 CFAR: c00000000029d90c DAR: 0000000000000000 DSISR: 40000000 IRQMASK: 0 ... NIP [c00000000029d800] t_probe_next+0x60/0x180 LR [c00000000029dac4] t_mod_start+0x1a4/0x1f0 Call Trace: [c0002017fae8bc90] [c000000000cdbc40] _cond_resched+0x10/0xb0 (unreliable) [c0002017fae8bce0] [c0000000002a15b0] t_start+0xf0/0x1c0 [c0002017fae8bd30] [c0000000004ec2b4] seq_read+0x184/0x640 [c0002017fae8bdd0] [c0000000004a57bc] sys_read+0x10c/0x300 [c0002017fae8be30] [c00000000000b388] system_call+0x5c/0x70 The test (ftrace_set_ftrace_filter.sh) is part of ftrace stress tests and the crash happens when the test does 'cat $TRACING_PATH/set_ftrace_filter'. The address points to the second line below, in t_probe_next(), where filter_hash is dereferenced: hash = iter->probe->ops.func_hash->filter_hash; size = 1 << hash->size_bits; This happens due to a race with register_ftrace_function_probe(). A new ftrace_func_probe is created and added into the func_probes list in trace_array under ftrace_lock. However, before initializing the filter, we drop ftrace_lock, and re-acquire it after acquiring regex_lock. If another process is trying to read set_ftrace_filter, it will be able to acquire ftrace_lock during this window and it will end up seeing a NULL filter_hash. Fix this by just checking for a NULL filter_hash in t_probe_next(). If the filter_hash is NULL, then this probe is just being added and we can simply return from here. Link: http://lkml.kernel.org/r/05e021f757625cbbb006fad41380323dbe4e3b43.1562249521.git.naveen.n.rao@linux.vnet.ibm.com Cc: stable@vger.kernel.org Fixes: 7b60f3d876156 ("ftrace: Dynamically create the probe ftrace_ops for the trace_array") Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
2019-07-31tracing: Use CONFIG_PREEMPTIONThomas Gleixner
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>
2019-07-18Merge tag 'trace-v5.3' of ↵Linus Torvalds
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 ...