- 11 Feb, 2020 2 commits
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Tom Zanussi authored
There's no reason to return -EINVAL when tracing a synthetic event if it's soft disabled - treat it the same as if it were hard disabled and return normally. Have synth_event_trace() and synth_event_trace_array() just return normally, and have synth_event_trace_start set the trace state to disabled and return. Link: http://lkml.kernel.org/r/df5d02a1625aff97c9866506c5bada6a069982ba.1581374549.git.zanussi@kernel.org Fixes: 8dcc53ad ("tracing: Add synth_event_trace() and related functions") Signed-off-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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Tom Zanussi authored
If the ring_buffer reserve in synth_event_trace_start() fails, the matching ring_buffer_nest_end() should be called in the error code, since nothing else will ever call it in this case. Link: http://lkml.kernel.org/r/20abc444b3eeff76425f895815380abe7aa53ff8.1581374549.git.zanussi@kernel.org Fixes: 8dcc53ad ("tracing: Add synth_event_trace() and related functions") Signed-off-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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- 10 Feb, 2020 6 commits
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Masami Hiramatsu authored
Suppress non-error messages when applying new bootconfig to initrd image. To enable it, replace printf for error message with pr_err() macro. This also adds a testcase for this fix. Link: http://lkml.kernel.org/r/158125351377.16911.13283712972275131160.stgit@devnote2Reported-by: Michael Ellerman <mpe@ellerman.id.au> Tested-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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Masami Hiramatsu authored
To reduce the large static array from kernel data, allocate xbc_nodes array dynamically only if the kernel loads a bootconfig. Note that this also add dummy memblock.h for user-spacae bootconfig tool. Link: http://lkml.kernel.org/r/158108569699.3187.6512834527603883707.stgit@devnote2Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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Steven Rostedt (VMware) authored
The current implementation does a naive search of "bootconfig" on the kernel command line. But this could find "bootconfig" that is part of another option in quotes (although highly unlikely). But it also needs to find '--' on the kernel command line to know if it should append a '--' or not when a bootconfig in the initrd file has an "init" section. The check uses the naive strstr() to find to see if it exists. But this can return a false positive if it exists in an option and then the "init" section in the initrd will not be appended properly. Using parse_args() to find both of these will solve both of these problems. Link: https://lore.kernel.org/r/202002070954.C18E7F58B@keescook Fixes: 7495e092 ("bootconfig: Only load bootconfig if "bootconfig" is on the kernel cmdline") Fixes: 13199162 ("bootconfig: init: Allow admin to use bootconfig for init command line") Reported-by: Kees Cook <keescook@chromium.org> Reviewed-by: Kees Cook <keescook@chromium.org> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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Gustavo A. R. Silva authored
There is a potential execution path in which variable *ret* is returned without being properly initialized, previously. Fix this by initializing variable *ret* to 0. Link: http://lkml.kernel.org/r/20200205223404.GA3379@embeddedor Addresses-Coverity-ID: 1491142 ("Uninitialized scalar variable") Fixes: 2a588dd1 ("tracing: Add kprobe event command generation functions") Reviewed-by: Tom Zanussi <zanussi@kernel.org> Acked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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Masami Hiramatsu authored
Since there is no user except CONFIG_BOOT_CONFIG and no plan to use it from other functions, CONFIG_LIBXBC can be removed and we can use CONFIG_BOOT_CONFIG directly. Link: http://lkml.kernel.org/r/158098769281.939.16293492056419481105.stgit@devnote2Suggested-by: Geert Uytterhoeven <geert@linux-m68k.org> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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Masami Hiramatsu authored
Since printk() wrapper macro uses __VA_ARGS__ without "##" prefix, it causes a build error if there is no variable arguments (e.g. only fmt is specified.) To fix this error, use ##__VA_ARGS__ instead of __VAR_ARGS__. Link: http://lkml.kernel.org/r/158108370130.2758.10893830923800978011.stgit@devnote2 Fixes: 950313eb ("tools: bootconfig: Add bootconfig command") Reported-by: Michael Ellerman <mpe@ellerman.id.au> Tested-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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- 05 Feb, 2020 9 commits
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Masami Hiramatsu authored
Show the number of bootconfig nodes on boot message. Link: http://lkml.kernel.org/r/158091062297.27924.9051634676068550285.stgit@devnote2Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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Masami Hiramatsu authored
Show the number of bootconfig nodes when applying new bootconfig to initrd. Since there are limitations of bootconfig not only in its filesize, but also the number of nodes, the number should be shown when applying so that user can get the feeling of scale of current bootconfig. Link: http://lkml.kernel.org/r/158091061337.27924.10886706631693823982.stgit@devnote2Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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Masami Hiramatsu authored
Add more error messages for following cases. - Exceeding max number of nodes - Config tree data is empty (e.g. comment only) - Config data is empty or exceeding max size - bootconfig is already initialized Link: http://lkml.kernel.org/r/158091060401.27924.9024818742827122764.stgit@devnote2Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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Masami Hiramatsu authored
Use "bootconfig" (1 word) instead of "boot config" (2 words) in the boot message. Link: http://lkml.kernel.org/r/158091059459.27924.14414336187441539879.stgit@devnote2Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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Steven Rostedt (VMware) authored
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: b9b0c831 ("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>
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Steven Rostedt (VMware) authored
Because the function graph tracer can execute in sections where RCU is not "watching", the rcu_dereference_sched() for the has needs to be open coded. This is fine because the RCU "flavor" of the ftrace hash is protected by its own RCU handling (it does its own little synchronization on every CPU and does not rely on RCU sched). Acked-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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Amol Grover authored
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.comSigned-off-by: Amol Grover <frextrite@gmail.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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Amol Grover authored
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.comReviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Amol Grover <frextrite@gmail.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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Steven Rostedt (VMware) authored
As the bootconfig is appended to the initrd it is not as easy to modify as the kernel command line. If there's some issue with the kernel, and the developer wants to boot a pristine kernel, it should not be needed to modify the initrd to remove the bootconfig for a single boot. As bootconfig is silently added (if the admin does not know where to look they may not know it's being loaded). It should be explicitly added to the kernel cmdline. The loading of the bootconfig is only done if "bootconfig" is on the kernel command line. This will let admins know that the kernel command line is extended. Note, after adding printk()s for when the size is too great or the checksum is wrong, exposed that the current method always looked for the boot config, and if this size and checksum matched, it would parse it (as if either is wrong a printk has been added to show this). It's better to only check this if the boot config is asked to be looked for. Link: https://lore.kernel.org/r/CAHk-=wjfjO+h6bQzrTf=YCZA53Y3EDyAs3Z4gEsT7icA3u_Psw@mail.gmail.comAcked-by: Masami Hiramatsu <mhiramat@kernel.org> Suggested-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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- 01 Feb, 2020 3 commits
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Tom Zanussi authored
The dynevent_cmd commands that build up the command string don't need to do that themselves - there's a seq_buf facility that does pretty much the same thing those command are doing manually, so use it instead. Link: http://lkml.kernel.org/r/eb8a6e835c964d0ab8a38cbf5ffa60746b54a465.1580506712.git.zanussi@kernel.orgReviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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Tom Zanussi authored
The final addition to q is unnecessary, since q isn't ever used afterwards. Link: http://lkml.kernel.org/r/7880a1268217886cdba7035526650195668da856.1580506712.git.zanussi@kernel.orgReviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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Tom Zanussi authored
It's kind of strange to have check_arg() callbacks as part of the arg objects themselves; it makes more sense to just pass these in when the args are added instead. Remove the check_arg() callbacks from those objects which also means removing the check_arg() args from the init functions, adding them to the add functions and fixing up existing callers. Link: http://lkml.kernel.org/r/c7708d6f177fcbe1a36b6e4e8e150907df0fa5d2.1580506712.git.zanussi@kernel.orgReviewed-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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- 31 Jan, 2020 3 commits
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Tom Zanussi authored
The synth_event trace code contains some almost identical functions and some small functions that are called only once - consolidate the common code into single functions and fold in the small functions to simplify the code overall. Link: http://lkml.kernel.org/r/d1c8d8ad124a653b7543afe801d38c199ca5c20e.1580506712.git.zanussi@kernel.orgSigned-off-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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Tom Zanussi authored
The patch 'tracing: Fix histogram code when expression has same var as value' added code to return an existing variable reference when creating a new variable reference, which resulted in var_ref_vals slots being reused instead of being duplicated. The implementation of the trace action assumes that the end of the var_ref_vals array starting at action_data.var_ref_idx corresponds to the values that will be assigned to the trace params. The patch mentioned above invalidates that assumption, which means that each param needs to explicitly specify its index into var_ref_vals. This fix changes action_data.var_ref_idx to an array of var ref indexes to account for that. Link: https://lore.kernel.org/r/1580335695.6220.8.camel@kernel.org Fixes: 8bcebc77 ("tracing: Fix histogram code when expression has same var as value") Signed-off-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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Tom Zanussi authored
Have trace_boot_add_synth_event() use the synth_event interface. Also, rename synth_event_run_cmd() to synth_event_run_command() now that trace_boot's version is gone. Link: http://lkml.kernel.org/r/94f1fa0e31846d0bddca916b8663404b20559e34.1580323897.git.zanussi@kernel.orgAcked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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- 30 Jan, 2020 17 commits
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Steven Rostedt (VMware) authored
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>
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Steven Rostedt (VMware) authored
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>
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Steven Rostedt (VMware) authored
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>
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Steven Rostedt (VMware) authored
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>
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Tom Zanussi authored
Add Documentation for creating and generating synthetic events from modules. Link: http://lkml.kernel.org/r/734bf8789ff8700000c9acde61a553427910ddb5.1580323897.git.zanussi@kernel.orgAcked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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Tom Zanussi authored
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.orgAcked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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Tom Zanussi authored
Have trace_boot_add_kprobe_event() use the kprobe_event interface. Also, rename kprobe_event_run_cmd() to kprobe_event_run_command() now that trace_boot's version is gone. Link: http://lkml.kernel.org/r/af5429d11291ab1e9a85a0ff944af3b2bcf193c7.1580323897.git.zanussi@kernel.orgAcked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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Tom Zanussi authored
Add functions used to generate kprobe event commands, built on top of the dynevent_cmd interface. kprobe_event_gen_cmd_start() is used to create a kprobe event command using a variable arg list, and kretprobe_event_gen_cmd_start() does the same for kretprobe event commands. kprobe_event_add_fields() can be used to add single fields one by one or as a group. Once all desired fields are added, kprobe_event_gen_cmd_end() or kretprobe_event_gen_cmd_end() respectively are used to actually execute the command and create the event. Link: http://lkml.kernel.org/r/95cc4696502bb6017f9126f306a45ad19b4cc14f.1580323897.git.zanussi@kernel.orgAcked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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Tom Zanussi authored
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.orgAcked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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Tom Zanussi authored
Add an exported function named synth_event_trace(), allowing modules or other kernel code to trace synthetic events. Also added are several functions that allow the same functionality to be broken out in a piecewise fashion, which are useful in situations where tracing an event from a full array of values would be cumbersome. Those functions are synth_event_trace_start/end() and synth_event_add_(next)_val(). Link: http://lkml.kernel.org/r/7a84de5f1854acf4144b57efe835ca645afa764f.1580323897.git.zanussi@kernel.orgAcked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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Tom Zanussi authored
Add functions used to generate synthetic event commands, built on top of the dynevent_cmd interface. synth_event_gen_cmd_start() is used to create a synthetic event command using a variable arg list and synth_event_gen_cmd_array_start() does the same thing but using an array of field descriptors. synth_event_add_field(), synth_event_add_field_str() and synth_event_add_fields() can be used to add single fields one by one or as a group. Once all desired fields are added, synth_event_gen_cmd_end() is used to actually execute the command and create the event. synth_event_create() does everything, including creating the event, in a single call. Link: http://lkml.kernel.org/r/38fef702fad5ef208009f459552f34a94befd860.1580323897.git.zanussi@kernel.orgAcked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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Tom Zanussi authored
Add an interface used to build up dynamic event creation commands, such as synthetic and kprobe events. Interfaces specific to those particular types of events and others can be built on top of this interface. Command creation is started by first using the dynevent_cmd_init() function to initialize the dynevent_cmd object. Following that, args are appended and optionally checked by the dynevent_arg_add() and dynevent_arg_pair_add() functions, which use objects representing arguments and pairs of arguments, initialized respectively by dynevent_arg_init() and dynevent_arg_pair_init(). Finally, once all args have been successfully added, the command is finalized and actually created using dynevent_create(). The code here for actually printing into the dyn_event->cmd buffer using snprintf() etc was adapted from v4 of Masami's 'tracing/boot: Add synthetic event support' patch. Link: http://lkml.kernel.org/r/1f65fa44390b6f238f6036777c3784ced1dcc6a0.1580323897.git.zanussi@kernel.orgSigned-off-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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Tom Zanussi authored
create_or_delete_synth_event() contains code to delete a synthetic event, which would be useful on its own - specifically, it would be useful to allow event-creating modules to call it separately. Separate out the delete code from that function and create an exported function named synth_event_delete(). Link: http://lkml.kernel.org/r/050db3b06df7f0a4b8a2922da602d1d879c7c1c2.1580323897.git.zanussi@kernel.orgAcked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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Tom Zanussi authored
Add a function to get an event file and prevent it from going away on module or instance removal. trace_get_event_file() will find an event file in a given instance (if instance is NULL, it assumes the top trace array) and return it, pinning the instance's trace array as well as the event's module, if applicable, so they won't go away while in use. trace_put_event_file() does the matching release. Link: http://lkml.kernel.org/r/bb31ac4bdda168d5ed3c4b5f5a4c8f633e8d9118.1580323897.git.zanussi@kernel.orgAcked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Tom Zanussi <zanussi@kernel.org> [ Moved trace_array_put() to end of trace_put_event_file() ] Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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Tom Zanussi authored
Add a new trace_array_find() function that can be used to find a trace array given the instance name, and replace existing code that does the same thing with it. Also add trace_array_find_get() which does the same but returns the trace array after upping its refcount. Also make both available for use outside of trace.c. Link: http://lkml.kernel.org/r/cb68528c975eba95bee4561ac67dd1499423b2e5.1580323897.git.zanussi@kernel.orgAcked-by: Masami Hiramatsu <mhiramat@kernel.org> Signed-off-by: Tom Zanussi <zanussi@kernel.org> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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Vasily Averin authored
if seq_file .next fuction does not change position index, read after some lseek can generate unexpected output. Without patch: # dd bs=30 skip=1 if=/sys/kernel/tracing/events/sched/sched_switch/trigger dd: /sys/kernel/tracing/events/sched/sched_switch/trigger: cannot skip to specified offset n traceoff snapshot stacktrace enable_event disable_event enable_hist disable_hist hist # Available triggers: # traceon traceoff snapshot stacktrace enable_event disable_event enable_hist disable_hist hist 6+1 records in 6+1 records out 206 bytes copied, 0.00027916 s, 738 kB/s Notice the printing of "# Available triggers:..." after the line. With the patch: # dd bs=30 skip=1 if=/sys/kernel/tracing/events/sched/sched_switch/trigger dd: /sys/kernel/tracing/events/sched/sched_switch/trigger: cannot skip to specified offset n traceoff snapshot stacktrace enable_event disable_event enable_hist disable_hist hist 2+1 records in 2+1 records out 88 bytes copied, 0.000526867 s, 167 kB/s It only prints the end of the file, and does not restart. Link: http://lkml.kernel.org/r/3c35ee24-dd3a-8119-9c19-552ed253388a@virtuozzo.com https://bugzilla.kernel.org/show_bug.cgi?id=206283Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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Vasily Averin authored
if seq_file .next fuction does not change position index, read after some lseek can generate unexpected output. Link: http://lkml.kernel.org/r/7ad85b22-1866-977c-db17-88ac438bc764@virtuozzo.comSigned-off-by: Vasily Averin <vvs@virtuozzo.com> [ This is not a bug fix, it just makes it "technically correct" which is why I applied it. NULL is only returned on an anomaly which triggers a WARN_ON ] Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
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