user/sven/linux.git/kernel/trace/trace_boot.c, branch v5.8.8

tracing/boottime: Fix kprobe multiple events

2020-06-24T01:51:50Z

Fix boottime kprobe events to report and abort after each failure when adding probes. As an example, when we try to set multiprobe kprobe events in bootconfig like this: ftrace.event.kprobes.vfsevents { probes = "vfs_read $arg1 $arg2,, !error! not reported;?", // leads to error "vfs_write $arg1 $arg2" } This will not work as expected. After commit da0f1f4167e3af69e ("tracing/boottime: Fix kprobe event API usage"), the function trace_boot_add_kprobe_event will not produce any error message when adding a probe fails at kprobe_event_gen_cmd_start. Furthermore, we continue to add probes when kprobe_event_gen_cmd_end fails (and kprobe_event_gen_cmd_start did not fail). In this case the function even returns successfully when the last call to kprobe_event_gen_cmd_end is successful. The behaviour of reporting and aborting after failures is not consistent. The function trace_boot_add_kprobe_event now reports each failure and stops adding probes immediately. Link: https://lkml.kernel.org/r/20200618163301.25854-1-sascha.ortmann@stud.uni-hannover.de Cc: stable@vger.kernel.org Cc: linux-kernel@i4.cs.fau.de Co-developed-by: Maximilian Werner Fixes: da0f1f4167e3 ("tracing/boottime: Fix kprobe event API usage") Acked-by: Masami Hiramatsu Signed-off-by: Maximilian Werner Signed-off-by: Sascha Ortmann Signed-off-by: Steven Rostedt (VMware)

tracing/boot: Fix config dependency for synthedic event

2020-06-24T01:51:22Z

Since commit 726721a51838 ("tracing: Move synthetic events to a separate file") decoupled synthetic event from histogram, boot-time tracing also has to check CONFIG_SYNTH_EVENT instead of CONFIG_HIST_TRIGGERS. Link: http://lkml.kernel.org/r/159262475441.185015.5300725180746017555.stgit@devnote2 Fixes: 726721a51838 ("tracing: Move synthetic events to a separate file") Reviewed-by: Tom Zanussi Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware)

tracing/boottime: Fix kprobe event API usage

2020-05-06T13:04:11Z

Fix boottime kprobe events to use API correctly for multiple events. For example, when we set a multiprobe kprobe events in bootconfig like below, ftrace.event.kprobes.myevent { probes = "vfs_read $arg1 $arg2", "vfs_write $arg1 $arg2" } This cause an error; trace_boot: Failed to add probe: p:kprobes/myevent (null) vfs_read $arg1 $arg2 vfs_write $arg1 $arg2 This shows the 1st argument becomes NULL and multiprobes are merged to 1 probe. Link: http://lkml.kernel.org/r/158779375766.6082.201939936008972838.stgit@devnote2 Cc: Ingo Molnar Cc: stable@vger.kernel.org Fixes: 29a154810546 ("tracing: Change trace_boot to use kprobe_event interface") Reviewed-by: Tom Zanussi Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware)

tracing: Change trace_boot to use synth_event interface

2020-01-31T17:59:26Z

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.org Acked-by: Masami Hiramatsu Signed-off-by: Tom Zanussi Signed-off-by: Steven Rostedt (VMware)

tracing: Change trace_boot to use kprobe_event interface

2020-01-30T14:46:28Z

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.org Acked-by: Masami Hiramatsu Signed-off-by: Tom Zanussi Signed-off-by: Steven Rostedt (VMware)

tracing/boot: Move external function declarations to kernel/trace/trace.h

2020-01-29T13:49:04Z

Move external function declarations into kernel/trace/trace.h from trace_boot.c for tracing subsystem internal use. Link: http://lkml.kernel.org/r/158029060405.12381.11944554430359702545.stgit@devnote2 Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware)

tracing/boot: Include required headers and sort it alphabetically

2020-01-29T13:48:44Z

Include some required (but currently indirectly included) headers and sort it alphabetically. Link: http://lkml.kernel.org/r/158029059514.12381.6597832266860248781.stgit@devnote2 Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware)

tracing: Decrement trace_array when bootconfig creates an instance

2020-01-25T02:29:13Z

The trace_array_get_by_name() creates a ftrace instance and trace_array_put() is used to remove the reference. Even though the trace_array_get_by_name() creates the instance, it also adds a reference count to it, that prevents user space from removing it. As the bootconfig just creates the instance on boot up, it should still be used where it can be deleted by user space after boot. A trace_array_put() is required to let that happen. Also, change the documentation on trace_array_get_by_name() to make this not be so confusing. Link: https://lore.kernel.org/r/20200124205927.76128804@rorschach.local.home Fixes: 4f712a4d04a4e ("tracing/boot: Add instance node support") Acked-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware)

tracing/boot: Fix an IS_ERR() vs NULL bug

2020-01-21T23:41:39Z

The trace_array_get_by_name() function doesn't return error pointers, it returns NULL on error. Link: http://lkml.kernel.org/r/20200117053007.5h2juv272pokqhtq@kili.mountain Fixes: 4f712a4d04a4 ("tracing/boot: Add instance node support") Acked-by: Masami Hiramatsu Signed-off-by: Dan Carpenter Signed-off-by: Steven Rostedt (VMware)

tracing/boot: Add function tracer filter options

2020-01-13T18:19:42Z

Add below function-tracer filter options to boot-time tracing. - ftrace.[instance.INSTANCE.]ftrace.filters This will take an array of tracing function filter rules - ftrace.[instance.INSTANCE.]ftrace.notraces This will take an array of NON-tracing function filter rules Link: http://lkml.kernel.org/r/157867244841.17873.10933616628243103561.stgit@devnote2 Signed-off-by: Masami Hiramatsu Signed-off-by: Steven Rostedt (VMware)