commit dd4adb986a upstream.
The tracing selftest "event-filter-function.tc" was failing because it
first runs the "sample_events" function that triggers the kmem_cache_free
event and it looks at what function was used during a call to "ls".
But the first time it calls this, it could trigger events that are used to
pull pages into the page cache.
The rest of the test uses the function it finds during that call to see if
it will be called in subsequent "sample_events" calls. But if there's no
need to pull pages into the page cache, it will not trigger that function
and the test will fail.
Call the "sample_events" twice to trigger all the page cache work before
it calls it to find a function to use in subsequent checks.
Cc: stable@vger.kernel.org
Fixes: eb50d0f250 ("selftests/ftrace: Choose target function for filter test from samples")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 213879061a ]
The subsystem event test enables all "sched" events and makes sure there's
at least 3 different events in the output. It used to cat the entire trace
file to | wc -l, but on slow machines, that could last a very long time.
To solve that, it was changed to just read the first 100 lines of the
trace file. This can cause false failures as some events repeat so often,
that the 100 lines that are examined could possibly be of only one event.
Instead, create an awk script that looks for 3 different events and will
exit out after it finds them. This will find the 3 events the test looks
for (eventually if it works), and still exit out after the test is
satisfied and not cause slower machines to run forever.
Link: https://lore.kernel.org/r/20250721134212.53c3e140@batman.local.home
Reported-by: Tengda Wu <wutengda@huaweicloud.com>
Closes: https://lore.kernel.org/all/20250710130134.591066-1-wutengda@huaweicloud.com/
Fixes: 1a4ea83a6e ("selftests/ftrace: Limit length in subsystem-enable tests")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 777f290ab3 ]
In 'NOFENTRY_ARGS' test case for syntax check, any offset X of
`vfs_read+X` except function entry offset (0) fits the criterion,
even if that offset is not at instruction boundary, as the parser
comes before probing. But with "ENDBR64" instruction on x86, offset
4 is treated as function entry. So, X can't be 4 as well. Thus, 8
was used as offset for the test case. On 64-bit powerpc though, any
offset <= 16 can be considered function entry depending on build
configuration (see arch_kprobe_on_func_entry() for implementation
details). So, use `vfs_read+20` to accommodate that scenario too.
Link: https://lore.kernel.org/r/20241129202621.721159-1-hbathini@linux.ibm.com
Fixes: 4231f30fcc ("selftests/ftrace: Add BTF arguments test cases")
Suggested-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Pull probes updates from Masami Hiramatsu:
- uprobes: make trace_uprobe->nhit counter a per-CPU one
This makes uprobe event's hit counter per-CPU for improving
scalability on multi-core environment
- kprobes: Remove obsoleted declaration for init_test_probes
Remove unused init_test_probes() from header
- Raw tracepoint probe supports raw tracepoint events on modules:
- add a function for iterating over all tracepoints in all modules
- add a function for iterating over tracepoints in a module
- support raw tracepoint events on modules
- support raw tracepoints on future loaded modules
- add a test for tracepoint events on modules"
* tag 'probes-v6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
sefltests/tracing: Add a test for tracepoint events on modules
tracing/fprobe: Support raw tracepoints on future loaded modules
tracing/fprobe: Support raw tracepoint events on modules
tracepoint: Support iterating tracepoints in a loading module
tracepoint: Support iterating over tracepoints on modules
kprobes: Remove obsoleted declaration for init_test_probes
uprobes: turn trace_uprobe's nhit counter to be per-CPU one
Support raw tracepoint events on future loaded (unloaded) modules.
This allows user to create raw tracepoint events which can be used from
module's __init functions.
Note: since the kernel does not have any information about the tracepoints
in the unloaded modules, fprobe events can not check whether the tracepoint
exists nor extend the BTF based arguments.
Link: https://lore.kernel.org/all/172397780593.286558.18360375226968537828.stgit@devnote2/
Suggested-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Fix eventfs ownership testcase to find mount point if stat -c "%m" failed.
This can happen on the system based on busybox. In this case, this will
try to use the current working directory, which should be a tracefs top
directory (and eventfs is mounted as a part of tracefs.)
If it does not work, the test is skipped as UNRESOLVED because of
the environmental problem.
Fixes: ee9793be08 ("tracing/selftests: Add ownership modification tests for eventfs")
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
The function "scheduler_tick" was renamed to "sched_tick" and a selftest
that used that function for testing function trace filtering used that
function as part of the test.
But the change causes it to fail when run on older kernels. As tests
should not fail on older kernels, add a check to see which name is
available before testing.
Fixes: 86dd6c04ef ("sched/balancing: Rename scheduler_tick() => sched_tick()")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
kprobe_args_{char,string}.tc are using available_filter_functions file
which is provided by function tracer. Thus if function tracer is disabled,
these tests are failed on recent kernels because tracefs_create_dir is
not raised events by adding a dynamic event.
Add available_filter_functions to requires line.
Fixes: 7c1130ea5c ("test: ftrace: Fix kprobe test for eventfs")
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
A regression happened where running the ownership test passes on the first
iteration but fails running it a second time. This was caught and fixed,
but a later change brought it back. The regression was missed because the
automated tests only run the tests once per boot.
Change the ownership test to iterate through the tests twice, as this will
catch the regression with a single run.
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Pull ftrace updates from Steven Rostedt:
"Rewrite of function graph tracer to allow multiple users
Up until now, the function graph tracer could only have a single user
attached to it. If another user tried to attach to the function graph
tracer while one was already attached, it would fail. Allowing
function graph tracer to have more than one user has been asked for
since 2009, but it required a rewrite to the logic to pull it off so
it never happened. Until now!
There's three systems that trace the return of a function. That is
kretprobes, function graph tracer, and BPF. kretprobes and function
graph tracing both do it similarly. The difference is that kretprobes
uses a shadow stack per callback and function graph tracer creates a
shadow stack for all tasks. The function graph tracer method makes it
possible to trace the return of all functions. As kretprobes now needs
that feature too, allowing it to use function graph tracer was needed.
BPF also wants to trace the return of many probes and its method
doesn't scale either. Having it use function graph tracer would
improve that.
By allowing function graph tracer to have multiple users allows both
kretprobes and BPF to use function graph tracer in these cases. This
will allow kretprobes code to be removed in the future as it's version
will no longer be needed.
Note, function graph tracer is only limited to 16 simultaneous users,
due to shadow stack size and allocated slots"
* tag 'ftrace-v6.11' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (49 commits)
fgraph: Use str_plural() in test_graph_storage_single()
function_graph: Add READ_ONCE() when accessing fgraph_array[]
ftrace: Add missing kerneldoc parameters to unregister_ftrace_direct()
function_graph: Everyone uses HAVE_FUNCTION_GRAPH_RET_ADDR_PTR, remove it
function_graph: Fix up ftrace_graph_ret_addr()
function_graph: Make fgraph_update_pid_func() a stub for !DYNAMIC_FTRACE
function_graph: Rename BYTE_NUMBER to CHAR_NUMBER in selftests
fgraph: Remove some unused functions
ftrace: Hide one more entry in stack trace when ftrace_pid is enabled
function_graph: Do not update pid func if CONFIG_DYNAMIC_FTRACE not enabled
function_graph: Make fgraph_do_direct static key static
ftrace: Fix prototypes for ftrace_startup/shutdown_subops()
ftrace: Assign RCU list variable with rcu_assign_ptr()
ftrace: Assign ftrace_list_end to ftrace_ops_list type cast to RCU
ftrace: Declare function_trace_op in header to quiet sparse warning
ftrace: Add comments to ftrace_hash_move() and friends
ftrace: Convert "inc" parameter to bool in ftrace_hash_rec_update_modify()
ftrace: Add comments to ftrace_hash_rec_disable/enable()
ftrace: Remove "filter_hash" parameter from __ftrace_hash_rec_update()
ftrace: Rename dup_hash() and comment it
...
The pid filtering test will set the pid filters and make sure that both
function and function_graph tracing honors the filters. But the
function_graph tracer test was failing because the PID was not being
filtered properly. That's because the funcgraph-proc option wasn't getting
set. Without that option the PID is not shown.
Instead we get:
+ cat trace
# tracer: function_graph
#
# CPU DURATION FUNCTION CALLS
# | | | | | | |
3) ! 143.685 us | kernel_clone();
3) ! 127.055 us | kernel_clone();
1) ! 127.170 us | kernel_clone();
3) ! 126.840 us | kernel_clone();
When we should be getting:
+ cat trace
# tracer: function_graph
#
# CPU TASK/PID DURATION FUNCTION CALLS
# | | | | | | | | |
4) bash-939 | # 1070.009 us | kernel_clone();
4) bash-939 | # 1116.903 us | kernel_clone();
5) bash-939 | ! 976.133 us | kernel_clone();
5) bash-939 | ! 954.012 us | kernel_clone();
The test looks for the pids it is filtering and will fail if it can not
find them. Without fungraph-proc option set, it will not be displayed and
the test will fail.
Link: https://lore.kernel.org/all/Zl9JFnzKGuUM10X2@J2N7QTR9R3/
Link: https://lore.kernel.org/linux-trace-kernel/20240604152550.0c01d7cd@gandalf.local.home
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Fixes: 35b944a997 ("selftests/ftrace: Add function_graph tracer to func-filter-pid test")
Reported-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Commit eb50d0f250 ("selftests/ftrace: Choose target function for filter
test from samples") choose the target function from samples, but sometimes
this test failes randomly because the target function does not hit at the
next time. So retry getting samples up to 10 times.
Fixes: eb50d0f250 ("selftests/ftrace: Choose target function for filter test from samples")
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
The kprobe_eventname.tc test checks if a function with .isra. can have a
kprobe attached to it. It loops through the kallsyms file for all the
functions that have the .isra. name, and checks if it exists in the
available_filter_functions file, and if it does, it uses it to attach a
kprobe to it.
The issue is that kprobes can not attach to functions that are listed more
than once in available_filter_functions. With the latest kernel, the
function that is found is: rapl_event_update.isra.0
# grep rapl_event_update.isra.0 /sys/kernel/tracing/available_filter_functions
rapl_event_update.isra.0
rapl_event_update.isra.0
It is listed twice. This causes the attached kprobe to it to fail which in
turn fails the test. Instead of just picking the function function that is
found in available_filter_functions, pick the first one that is listed
only once in available_filter_functions.
Cc: stable@vger.kernel.org
Fixes: 604e354823 ("selftests/ftrace: Select an existing function in kprobe_eventname test")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Update required config options for running all tests.
This also sorts the config entries alphabetically.
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
The dynevent/test_duplicates.tc test case uses `syscalls/sys_enter_openat`
event for defining eprobe on it. Since this `syscalls` events depend on
CONFIG_FTRACE_SYSCALLS=y, if it is not set, the test will fail.
Add the event file to `required` line so that the test will return
`unsupported` result.
Fixes: 297e1dcdca ("selftests/ftrace: Add selftest for testing duplicate eprobes and kprobes")
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Pull probes updates from Masami Hiramatsu:
- tracing/probes: Add new pseudo-types %pd and %pD support for dumping
dentry name from 'struct dentry *' and file name from 'struct file *'
- uprobes performance optimizations:
- Speed up the BPF uprobe event by delaying the fetching of the
uprobe event arguments that are not used in BPF
- Avoid locking by speculatively checking whether uprobe event is
valid
- Reduce lock contention by using read/write_lock instead of
spinlock for uprobe list operation. This improved BPF uprobe
benchmark result 43% on average
- rethook: Remove non-fatal warning messages when tracing stack from
BPF and skip rcu_is_watching() validation in rethook if possible
- objpool: Optimize objpool (which is used by kretprobes and fprobe as
rethook backend storage) by inlining functions and avoid caching
nr_cpu_ids because it is a const value
- fprobe: Add entry/exit callbacks types (code cleanup)
- kprobes: Check ftrace was killed in kprobes if it uses ftrace
* tag 'probes-v6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
kprobe/ftrace: bail out if ftrace was killed
selftests/ftrace: Fix required features for VFS type test case
objpool: cache nr_possible_cpus() and avoid caching nr_cpu_ids
objpool: enable inlining objpool_push() and objpool_pop() operations
rethook: honor CONFIG_FTRACE_VALIDATE_RCU_IS_WATCHING in rethook_try_get()
ftrace: make extra rcu_is_watching() validation check optional
uprobes: reduce contention on uprobes_tree access
rethook: Remove warning messages printed for finding return address of a frame.
fprobe: Add entry/exit callbacks types
selftests/ftrace: add fprobe test cases for VFS type "%pd" and "%pD"
selftests/ftrace: add kprobe test cases for VFS type "%pd" and "%pD"
Documentation: tracing: add new type '%pd' and '%pD' for kprobe
tracing/probes: support '%pD' type for print struct file's name
tracing/probes: support '%pd' type for print struct dentry's name
uprobes: add speculative lockless system-wide uprobe filter check
uprobes: prepare uprobe args buffer lazily
uprobes: encapsulate preparation of uprobe args buffer
Pull kselftest updates from Shuah Khan:
- make framework and tests reporting KTAP compliant
- make ktap_helpers and power_supply test POSIX compliant
- add ksft_exit_fail_perror() to include errono in string form
- avoid clang reporting false positive static analysis errors about
functions that exit and never return. ksft_exit* functions are marked
__noreturn to address this problem
- add mechanism for reporting a KSFT_ result code
- fix build warnings related missing headers and unused variables
- fix clang build failures
- cleanups to resctrl test
- add host arch for LLVM builds
* tag 'linux_kselftest-next-6.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: (44 commits)
selftests/sgx: Include KHDR_INCLUDES in Makefile
selftests: Compile kselftest headers with -D_GNU_SOURCE
selftests/resctrl: fix clang build warnings related to abs(), labs() calls
selftests/ftrace: Fix checkbashisms errors
selftests/ftrace: Fix BTFARG testcase to check fprobe is enabled correctly
selftests/capabilities: fix warn_unused_result build warnings
selftests: filesystems: add missing stddef header
selftests: kselftest_deps: fix l5_test() empty variable
selftests: default to host arch for LLVM builds
selftests/resctrl: fix clang build failure: use LOCAL_HDRS
selftests/binderfs: use the Makefile's rules, not Make's implicit rules
Documentation: kselftest: fix codeblock
selftests: kselftest: Make ksft_exit functions return void instead of int
selftests: x86: ksft_exit_pass() does not return
selftests: timers: ksft_exit functions do not return
selftests: sync: ksft_exit_pass() does not return
selftests/resctrl: ksft_exit_skip() does not return
selftests: pidfd: ksft_exit functions do not return
selftests/mm: ksft_exit functions do not return
selftests: membarrier: ksft_exit_pass() does not return
...
Pull scheduler updates from Ingo Molnar:
- Add cpufreq pressure feedback for the scheduler
- Rework misfit load-balancing wrt affinity restrictions
- Clean up and simplify the code around ::overutilized and
::overload access.
- Simplify sched_balance_newidle()
- Bump SCHEDSTAT_VERSION to 16 due to a cleanup of CPU_MAX_IDLE_TYPES
handling that changed the output.
- Rework & clean up <asm/vtime.h> interactions wrt arch_vtime_task_switch()
- Reorganize, clean up and unify most of the higher level
scheduler balancing function names around the sched_balance_*()
prefix
- Simplify the balancing flag code (sched_balance_running)
- Miscellaneous cleanups & fixes
* tag 'sched-core-2024-05-13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (50 commits)
sched/pelt: Remove shift of thermal clock
sched/cpufreq: Rename arch_update_thermal_pressure() => arch_update_hw_pressure()
thermal/cpufreq: Remove arch_update_thermal_pressure()
sched/cpufreq: Take cpufreq feedback into account
cpufreq: Add a cpufreq pressure feedback for the scheduler
sched/fair: Fix update of rd->sg_overutilized
sched/vtime: Do not include <asm/vtime.h> header
s390/irq,nmi: Include <asm/vtime.h> header directly
s390/vtime: Remove unused __ARCH_HAS_VTIME_TASK_SWITCH leftover
sched/vtime: Get rid of generic vtime_task_switch() implementation
sched/vtime: Remove confusing arch_vtime_task_switch() declaration
sched/balancing: Simplify the sg_status bitmask and use separate ->overloaded and ->overutilized flags
sched/fair: Rename set_rd_overutilized_status() to set_rd_overutilized()
sched/fair: Rename SG_OVERLOAD to SG_OVERLOADED
sched/fair: Rename {set|get}_rd_overload() to {set|get}_rd_overloaded()
sched/fair: Rename root_domain::overload to ::overloaded
sched/fair: Use helper functions to access root_domain::overload
sched/fair: Check root_domain::overload value before update
sched/fair: Combine EAS check with root_domain::overutilized access
sched/fair: Simplify the continue_balancing logic in sched_balance_newidle()
...
Since the VFS type argument test case uses fprobe events, it must
check the availablity of dynamic_events file and fprobe events syntax
in README. Without this fix, the test fails if CONFIG_FPROBE_EVENTS=n.
Link: https://lore.kernel.org/all/171478301645.110267.464634740467398506.stgit@devnote2/
Fixes: ee97e5e135 ("selftests/ftrace: add fprobe test cases for VFS type "%pd" and "%pD"")
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Fix the below checkbashisms errors. Because of these errors, these tests
will fail on dash shell.
possible bashism in test.d/kprobe/kretprobe_entry_arg.tc line 14 ('function' is useless):
function streq() {
possible bashism in test.d/dynevent/fprobe_entry_arg.tc line 14 ('function' is useless):
function streq() {
Fixes: f6e2253a61 ("selftests/ftrace: Add test cases for entry args at function exit")
Cc: stable@vger.kernel.org
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Since the dynevent/add_remove_btfarg.tc test case forgets to ensure that
fprobe is enabled for some structure field access tests which uses the
fprobe, it fails if CONFIG_FPROBE=n or CONFIG_FPROBE_EVENTS=n.
Fixes it to ensure the fprobe events are supported.
Fixes: d892d3d3d8 ("selftests/ftrace: Add BTF fields access testcases")
Cc: stable@vger.kernel.org
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
In order to facilitate debugging of issues from automated runs of the ftrace
selftests turn on verbose logging by default when run from the kselftest
runner. This is primarily used by automated systems where developers may
not have direct access to the system so defaulting to providing diagnostic
information which might help debug problems seems like a good idea.
When tests pass no extra output is generated, when they fail a full log of
the test run is provided. Since this really is rather verbose when there are
a large number of test failures or output is slow (eg, with a serial
console) this could substantially increase the run time for the tests which
might present problems with timeout detection for affected systems,
hopefully we keep the tests running well enough that this is not too much
of an issue.
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
When -v is specified ftracetest will dump logs of test execution to the
console which if -K is also specified for KTAP output will result in
output that is not properly KTAP formatted. All that's required for KTAP
formatting is that anything we log have a '#' at the start of the line so
we can improve things by washing the output through a simple read loop.
This will help automated parsers when verbose mode is enabled.
Signed-off-by: Mark Brown <broonie@kernel.org>
Reviewed-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
This patch adds test cases for new print format type "%pd/%pD".The test cases
test the following items:
1. Test README if add "%pd/%pD" type;
2. Test "%pd" type for dput();
3. Test "%pD" type for vfs_read();
This test case require enable CONFIG_HAVE_FUNCTION_ARG_ACCESS_API configuration.
Link: https://lore.kernel.org/all/20240322064308.284457-5-yebin10@huawei.com/
Signed-off-by: Ye Bin <yebin10@huawei.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
While sched* events being traced and sched* events continuously happen,
"[xx] event tracing - enable/disable with subsystem level files" would
not stop as on some slower systems it seems to take forever.
Select the first 100 lines of output would be enough to judge whether
there are more than 3 types of sched events.
Fixes: 815b18ea66 ("ftracetest: Add basic event tracing test cases")
Cc: stable@vger.kernel.org
Signed-off-by: Yuanhe Shu <xiangzao@linux.alibaba.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
The event filter function test has been failing in our internal test
farm:
| # not ok 33 event filter function - test event filtering on functions
Running the test in verbose mode indicates that this is because the test
erroneously determines that kmem_cache_free() is the most common caller
of kmem_cache_free():
# # + cut -d: -f3 trace
# # + sed s/call_site=([^+]*)+0x.*/1/
# # + sort
# # + uniq -c
# # + sort
# # + tail -n 1
# # + sed s/^[ 0-9]*//
# # + target_func=kmem_cache_free
... and as kmem_cache_free() doesn't call itself, setting this as the
filter function for kmem_cache_free() results in no hits, and
consequently the test fails:
# # + grep kmem_cache_free trace
# # + grep kmem_cache_free
# # + wc -l
# # + hitcnt=0
# # + grep kmem_cache_free trace
# # + grep -v kmem_cache_free
# # + wc -l
# # + misscnt=0
# # + [ 0 -eq 0 ]
# # + exit_fail
This seems to be because the system in question has tasks with ':' in
their name (which a number of kernel worker threads have). These show up
in the trace, e.g.
test:.sh-1299 [004] ..... 2886.040608: kmem_cache_free: call_site=putname+0xa4/0xc8 ptr=000000000f4d22f4 name=names_cache
... and so when we try to extact the call_site with:
cut -d: -f3 trace | sed 's/call_site=\([^+]*\)+0x.*/\1/'
... the 'cut' command will extrace the column containing
'kmem_cache_free' rather than the column containing 'call_site=...', and
the 'sed' command will leave this unchanged. Consequently, the test will
decide to use 'kmem_cache_free' as the filter function, resulting in the
failure seen above.
Fix this by matching the 'call_site=<func>' part specifically to extract
the function name.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reported-by: Aishwarya TCV <aishwarya.tcv@arm.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: linux-kernel@vger.kernel.org
Cc: linux-kselftest@vger.kernel.org
Cc: linux-trace-kernel@vger.kernel.org
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Pull probes updates from Masami Hiramatsu:
"x86 kprobes:
- Use boolean for some function return instead of 0 and 1
- Prohibit probing on INT/UD. This prevents user to put kprobe on
INTn/INT1/INT3/INTO and UD0/UD1/UD2 because these are used for a
special purpose in the kernel
- Boost Grp instructions. Because a few percent of kernel
instructions are Grp 2/3/4/5 and those are safe to be executed
without ip register fixup, allow those to be boosted (direct
execution on the trampoline buffer with a JMP)
tracing:
- Add function argument access from return events (kretprobe and
fprobe). This allows user to compare how a data structure field is
changed after executing a function. With BTF, return event also
accepts function argument access by name.
- Fix a wrong comment (using "Kretprobe" in fprobe)
- Cleanup a big probe argument parser function into three parts, type
parser, post-processing function, and main parser
- Cleanup to set nr_args field when initializing trace_probe instead
of counting up it while parsing
- Cleanup a redundant #else block from tracefs/README source code
- Update selftests to check entry argument access from return probes
- Documentation update about entry argument access from return
probes"
* tag 'probes-v6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
Documentation: tracing: Add entry argument access at function exit
selftests/ftrace: Add test cases for entry args at function exit
tracing/probes: Support $argN in return probe (kprobe and fprobe)
tracing: Remove redundant #else block for BTF args from README
tracing/probes: cleanup: Set trace_probe::nr_args at trace_probe_init
tracing/probes: Cleanup probe argument parser
tracing/fprobe-event: cleanup: Fix a wrong comment in fprobe event
x86/kprobes: Boost more instructions from grp2/3/4/5
x86/kprobes: Prohibit kprobing on INT and UD
x86/kprobes: Refactor can_{probe,boost} return type to bool
- Standardize on prefixing scheduler-internal functions defined
in <linux/sched.h> with sched_*() prefix. scheduler_tick() was
the only function using the scheduler_ prefix. Harmonize it.
- The other reason to rename it is the NOHZ scheduler tick
handling functions are already named sched_tick_*().
Make the 'git grep sched_tick' more meaningful.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Valentin Schneider <vschneid@redhat.com>
Reviewed-by: Shrikanth Hegde <sshegde@linux.ibm.com>
Link: https://lore.kernel.org/r/20240308111819.1101550-3-mingo@kernel.org
Support accessing $argN in the return probe events. This will help users to
record entry data in function return (exit) event for simplfing the function
entry/exit information in one event, and record the result values (e.g.
allocated object/initialized object) at function exit.
For example, if we have a function `int init_foo(struct foo *obj, int param)`
sometimes we want to check how `obj` is initialized. In such case, we can
define a new return event like below;
# echo 'r init_foo retval=$retval param=$arg2 field1=+0($arg1)' >> kprobe_events
Thus it records the function parameter `param` and its result `obj->field1`
(the dereference will be done in the function exit timing) value at once.
This also support fprobe, BTF args and'$arg*'. So if CONFIG_DEBUG_INFO_BTF
is enabled, we can trace both function parameters and the return value
by following command.
# echo 'f target_function%return $arg* $retval' >> dynamic_events
Link: https://lore.kernel.org/all/170952365552.229804.224112990211602895.stgit@devnote2/
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Add a test to exercize cpu hotplug with the function tracer active to
ensure that sensitive functions in idle path are excluded from being
traced. This helps catch issues such as the one fixed by commit
4b3338aaa7 ("powerpc/ftrace: Fix stack teardown in ftrace_no_trace").
Signed-off-by: Naveen N Rao <naveen@kernel.org>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Acked-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
The typo in the description shows up in test logs and output.
This patch submission is part of my application to the Linux Foundation
mentorship program: Linux kernel Bug Fixing Spring Unpaid 2024.
Signed-off-by: Ali Zahraee <ahzahraee@gmail.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Fix a typo in ftracetest script which is run when running the kselftests
for ftrace.
s/faii/fail
Signed-off-by: Kousik Sanagavarapu <five231003@gmail.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Pull tracing updates from Steven Rostedt:
- Allow kernel trace instance creation to specify what events are
created
Inside the kernel, a subsystem may create a tracing instance that it
can use to send events to user space. This sub-system may not care
about the thousands of events that exist in eventfs. Allow the
sub-system to specify what sub-systems of events it cares about, and
only those events are exposed to this instance.
- Allow the ring buffer to be broken up into bigger sub-buffers than
just the architecture page size.
A new tracefs file called "buffer_subbuf_size_kb" is created. The
user can now specify a minimum size the sub-buffer may be in
kilobytes. Note, that the implementation currently make the
sub-buffer size a power of 2 pages (1, 2, 4, 8, 16, ...) but the user
only writes in kilobyte size, and the sub-buffer will be updated to
the next size that it will can accommodate it. If the user writes in
10, it will change the size to be 4 pages on x86 (16K), as that is
the next available size that can hold 10K pages.
- Update the debug output when a corrupt time is detected in the ring
buffer. If the ring buffer detects inconsistent timestamps, there's a
debug config options that will dump the contents of the meta data of
the sub-buffer that is used for debugging. Add some more information
to this dump that helps with debugging.
- Add more timestamp debugging checks (only triggers when the config is
enabled)
- Increase the trace_seq iterator to 2 page sizes.
- Allow strings written into tracefs_marker to be larger. Up to just
under 2 page sizes (based on what trace_seq can hold).
- Increase the trace_maker_raw write to be as big as a sub-buffer can
hold.
- Remove 32 bit time stamp logic, now that the rb_time_cmpxchg() has
been removed.
- More selftests were added.
- Some code clean ups as well.
* tag 'trace-v6.8' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (29 commits)
ring-buffer: Remove stale comment from ring_buffer_size()
tracing histograms: Simplify parse_actions() function
tracing/selftests: Remove exec permissions from trace_marker.tc test
ring-buffer: Use subbuf_order for buffer page masking
tracing: Update subbuffer with kilobytes not page order
ringbuffer/selftest: Add basic selftest to test changing subbuf order
ring-buffer: Add documentation on the buffer_subbuf_order file
ring-buffer: Just update the subbuffers when changing their allocation order
ring-buffer: Keep the same size when updating the order
tracing: Stop the tracing while changing the ring buffer subbuf size
tracing: Update snapshot order along with main buffer order
ring-buffer: Make sure the spare sub buffer used for reads has same size
ring-buffer: Do no swap cpu buffers if order is different
ring-buffer: Clear pages on error in ring_buffer_subbuf_order_set() failure
ring-buffer: Read and write to ring buffers with custom sub buffer size
ring-buffer: Set new size of the ring buffer sub page
ring-buffer: Add interface for configuring trace sub buffer size
ring-buffer: Page size per ring buffer
ring-buffer: Have ring_buffer_print_page_header() be able to access ring_buffer_iter
ring-buffer: Check if absolute timestamp goes backwards
...
As there were bugs found with the ownership of eventfs dynamic file
creation. Add a test to test it.
It will remount tracefs with a different gid and check the ownership of
the eventfs directory, as well as the system and event directories. It
will also check the event file directories.
It then does a chgrp on each of these as well to see if they all get
updated as expected.
Then it remounts the tracefs file system back to the original group and
makes sure that all the updated files and directories were reset back to
the original ownership.
It does the same for instances that change the ownership of he instance
directory.
Note, because the uid is not reset by a remount, it is tested for every
file by switching it to a new owner and then back again.
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Tested-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
