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ring-buffer: Updates for v6.12:
- Merged v6.11-rc3 into trace/ring-buffer/core
The v6.10 ring buffer pull request was not made due to Mathieu Desnoyers
making a comment to the pull request. Mathieu and I resolved it on IRC,
but we did not let Linus know that it was resolved. Linus did not do the
pull thinking it still had some unresolved issues.
The ring buffer work for 6.12 was dependent on both this pull request as
well as the reserve_mem kernel command line option that was going upstream
through the memory management tree. The ring buffer repo was being used by
others so it could not be rebased. In order to continue the work, the
v6.11-rc3 branch was pulled in to get access to the reserve_mem work.
This has the 6.11 pull request that did not make it into 6.11, which was:
tracing/ring-buffer: Have persistent buffer across reboots
This allows for the tracing instance ring buffer to stay persistent across
reboots. The way this is done is by adding to the kernel command line:
trace_instance=boot_map@0x285400000:12M
This will reserve 12 megabytes at the address 0x285400000, and then map
the tracing instance "boot_map" ring buffer to that memory. This will
appear as a normal instance in the tracefs system:
/sys/kernel/tracing/instances/boot_map
A user could enable tracing in that instance, and on reboot or kernel
crash, if the memory is not wiped by the firmware, it will recreate the
trace in that instance. For example, if one was debugging a shutdown of a
kernel reboot:
# cd /sys/kernel/tracing
# echo function > instances/boot_map/current_tracer
# reboot
[..]
# cd /sys/kernel/tracing
# tail instances/boot_map/trace
swapper/0-1 [000] d..1. 164.549800: restore_boot_irq_mode <-native_machine_shutdown
swapper/0-1 [000] d..1. 164.549801: native_restore_boot_irq_mode <-native_machine_shutdown
swapper/0-1 [000] d..1. 164.549802: disconnect_bsp_APIC <-native_machine_shutdown
swapper/0-1 [000] d..1. 164.549811: hpet_disable <-native_machine_shutdown
swapper/0-1 [000] d..1. 164.549812: iommu_shutdown_noop <-native_machine_restart
swapper/0-1 [000] d..1. 164.549813: native_machine_emergency_restart <-__do_sys_reboot
swapper/0-1 [000] d..1. 164.549813: tboot_shutdown <-native_machine_emergency_restart
swapper/0-1 [000] d..1. 164.549820: acpi_reboot <-native_machine_emergency_restart
swapper/0-1 [000] d..1. 164.549821: acpi_reset <-acpi_reboot
swapper/0-1 [000] d..1. 164.549822: acpi_os_write_port <-acpi_reboot
On reboot, the buffer is examined to make sure it is valid. The validation
check even steps through every event to make sure the meta data of the
event is correct. If any test fails, it will simply reset the buffer, and
the buffer will be empty on boot.
The new changes for 6.12 are:
- Allow the tracing persistent boot buffer to use the "reserve_mem" option
Instead of having the admin find a physical address to store the persistent
buffer, which can be very tedious if they have to administrate several
different machines, allow them to use the "reserve_mem" option that will
find a location for them. It is not as reliable because of KASLR, as the
loading of the kernel in different locations can cause the memory
allocated to be inconsistent. Booting with "nokaslr" can make reserve_mem
more reliable.
- Have function graph tracer handle offsets from a previous boot.
The ring buffer output from a previous boot may have different addresses
due to kaslr. Have the function graph tracer handle these by using the
delta from the previous boot to the new boot address space.
- Only reset the saved meta offset when the buffer is started or reset
In the persistent memory meta data, it holds the previous address space
information, so that it can calculate the delta to have function tracing
work. But this gets updated after being read to hold the new address
space. But if the buffer isn't used for that boot, on reboot, the delta is
now calculated from the previous boot and not the boot that holds the data
in the ring buffer. This causes the functions not to be shown. Do not save
the address space information of the current kernel until it is being
recorded.
- Add a magic variable to test the valid meta data
Add a magic variable in the meta data that can also be used for
validation. The validator of the previous buffer doesn't need this magic
data, but it can be used if the meta data is changed by a new kernel, which
may have the same format that passes the validator but is used
differently. This magic number can also be used as a "versioning" of the
meta data.
- Align user space mapped ring buffer sub buffers to improve TLB entries
Linus mentioned that the mapped ring buffer sub buffers were misaligned
between the meta page and the sub-buffers, so that if the sub-buffers were
bigger than PAGE_SIZE, it wouldn't allow the TLB to use bigger entries.
- Add new kernel command line "traceoff" to disable tracing on boot for instances
If tracing is enabled for a boot instance, there needs a way to be able to
disable it on boot so that new events do not get entered into the ring
buffer and be mixed with events from a previous boot, as that can be
confusing.
- Allow trace_printk() to go to other instances
Currently, trace_printk() can only go to the top level instance. When
debugging with a persistent buffer, it is really useful to be able to add
trace_printk() to go to that buffer, so that you have access to them after
a crash.
- Do not use "bin_printk()" for traces to a boot instance
The bin_printk() saves only a pointer to the printk format in the ring
buffer, as the reader of the buffer can still have access to it. But this
is not the case if the buffer is from a previous boot. If the
trace_printk() is going to a "persistent" buffer, it will use the slower
version that writes the printk format into the buffer.
- Add command line option to allow trace_printk() to go to an instance
Allow the kernel command line to define which instance the trace_printk()
goes to, instead of forcing the admin to set it for every boot via the
tracefs options.
- Start a document that explains how to use tracefs to debug the kernel
- Add some more kernel selftests to test user mapped ring buffer
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Merge tag 'trace-ring-buffer-v6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace
Pull ring-buffer updates from Steven Rostedt:
- tracing/ring-buffer: persistent buffer across reboots
This allows for the tracing instance ring buffer to stay persistent
across reboots. The way this is done is by adding to the kernel
command line:
trace_instance=boot_map@0x285400000:12M
This will reserve 12 megabytes at the address 0x285400000, and then
map the tracing instance "boot_map" ring buffer to that memory. This
will appear as a normal instance in the tracefs system:
/sys/kernel/tracing/instances/boot_map
A user could enable tracing in that instance, and on reboot or kernel
crash, if the memory is not wiped by the firmware, it will recreate
the trace in that instance. For example, if one was debugging a
shutdown of a kernel reboot:
# cd /sys/kernel/tracing
# echo function > instances/boot_map/current_tracer
# reboot
[..]
# cd /sys/kernel/tracing
# tail instances/boot_map/trace
swapper/0-1 [000] d..1. 164.549800: restore_boot_irq_mode <-native_machine_shutdown
swapper/0-1 [000] d..1. 164.549801: native_restore_boot_irq_mode <-native_machine_shutdown
swapper/0-1 [000] d..1. 164.549802: disconnect_bsp_APIC <-native_machine_shutdown
swapper/0-1 [000] d..1. 164.549811: hpet_disable <-native_machine_shutdown
swapper/0-1 [000] d..1. 164.549812: iommu_shutdown_noop <-native_machine_restart
swapper/0-1 [000] d..1. 164.549813: native_machine_emergency_restart <-__do_sys_reboot
swapper/0-1 [000] d..1. 164.549813: tboot_shutdown <-native_machine_emergency_restart
swapper/0-1 [000] d..1. 164.549820: acpi_reboot <-native_machine_emergency_restart
swapper/0-1 [000] d..1. 164.549821: acpi_reset <-acpi_reboot
swapper/0-1 [000] d..1. 164.549822: acpi_os_write_port <-acpi_reboot
On reboot, the buffer is examined to make sure it is valid. The
validation check even steps through every event to make sure the meta
data of the event is correct. If any test fails, it will simply reset
the buffer, and the buffer will be empty on boot.
- Allow the tracing persistent boot buffer to use the "reserve_mem"
option
Instead of having the admin find a physical address to store the
persistent buffer, which can be very tedious if they have to
administrate several different machines, allow them to use the
"reserve_mem" option that will find a location for them. It is not as
reliable because of KASLR, as the loading of the kernel in different
locations can cause the memory allocated to be inconsistent. Booting
with "nokaslr" can make reserve_mem more reliable.
- Have function graph tracer handle offsets from a previous boot.
The ring buffer output from a previous boot may have different
addresses due to kaslr. Have the function graph tracer handle these
by using the delta from the previous boot to the new boot address
space.
- Only reset the saved meta offset when the buffer is started or reset
In the persistent memory meta data, it holds the previous address
space information, so that it can calculate the delta to have
function tracing work. But this gets updated after being read to hold
the new address space. But if the buffer isn't used for that boot, on
reboot, the delta is now calculated from the previous boot and not
the boot that holds the data in the ring buffer. This causes the
functions not to be shown. Do not save the address space information
of the current kernel until it is being recorded.
- Add a magic variable to test the valid meta data
Add a magic variable in the meta data that can also be used for
validation. The validator of the previous buffer doesn't need this
magic data, but it can be used if the meta data is changed by a new
kernel, which may have the same format that passes the validator but
is used differently. This magic number can also be used as a
"versioning" of the meta data.
- Align user space mapped ring buffer sub buffers to improve TLB
entries
Linus mentioned that the mapped ring buffer sub buffers were
misaligned between the meta page and the sub-buffers, so that if the
sub-buffers were bigger than PAGE_SIZE, it wouldn't allow the TLB to
use bigger entries.
- Add new kernel command line "traceoff" to disable tracing on boot for
instances
If tracing is enabled for a boot instance, there needs a way to be
able to disable it on boot so that new events do not get entered into
the ring buffer and be mixed with events from a previous boot, as
that can be confusing.
- Allow trace_printk() to go to other instances
Currently, trace_printk() can only go to the top level instance. When
debugging with a persistent buffer, it is really useful to be able to
add trace_printk() to go to that buffer, so that you have access to
them after a crash.
- Do not use "bin_printk()" for traces to a boot instance
The bin_printk() saves only a pointer to the printk format in the
ring buffer, as the reader of the buffer can still have access to it.
But this is not the case if the buffer is from a previous boot. If
the trace_printk() is going to a "persistent" buffer, it will use the
slower version that writes the printk format into the buffer.
- Add command line option to allow trace_printk() to go to an instance
Allow the kernel command line to define which instance the
trace_printk() goes to, instead of forcing the admin to set it for
every boot via the tracefs options.
- Start a document that explains how to use tracefs to debug the kernel
- Add some more kernel selftests to test user mapped ring buffer
* tag 'trace-ring-buffer-v6.12' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (28 commits)
selftests/ring-buffer: Handle meta-page bigger than the system
selftests/ring-buffer: Verify the entire meta-page padding
tracing/Documentation: Start a document on how to debug with tracing
tracing: Add option to set an instance to be the trace_printk destination
tracing: Have trace_printk not use binary prints if boot buffer
tracing: Allow trace_printk() to go to other instance buffers
tracing: Add "traceoff" flag to boot time tracing instances
ring-buffer: Align meta-page to sub-buffers for improved TLB usage
ring-buffer: Add magic and struct size to boot up meta data
ring-buffer: Don't reset persistent ring-buffer meta saved addresses
tracing/fgraph: Have fgraph handle previous boot function addresses
tracing: Allow boot instances to use reserve_mem boot memory
tracing: Fix ifdef of snapshots to not prevent last_boot_info file
ring-buffer: Use vma_pages() helper function
tracing: Fix NULL vs IS_ERR() check in enable_instances()
tracing: Add last boot delta offset for stack traces
tracing: Update function tracing output for previous boot buffer
tracing: Handle old buffer mappings for event strings and functions
tracing/ring-buffer: Add last_boot_info file to boot instance
ring-buffer: Save text and data locations in mapped meta data
...
This commit is contained in:
Linus Torvalds
commit
af9c191ac2
@ -6808,6 +6808,51 @@
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the same thing would happen if it was left off). The irq_handler_entry
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event, and all events under the "initcall" system.
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Flags can be added to the instance to modify its behavior when it is
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created. The flags are separated by '^'.
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The available flags are:
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traceoff - Have the tracing instance tracing disabled after it is created.
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traceprintk - Have trace_printk() write into this trace instance
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(note, "printk" and "trace_printk" can also be used)
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trace_instance=foo^traceoff^traceprintk,sched,irq
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The flags must come before the defined events.
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If memory has been reserved (see memmap for x86), the instance
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can use that memory:
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memmap=12M$0x284500000 trace_instance=boot_map@0x284500000:12M
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The above will create a "boot_map" instance that uses the physical
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memory at 0x284500000 that is 12Megs. The per CPU buffers of that
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instance will be split up accordingly.
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Alternatively, the memory can be reserved by the reserve_mem option:
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reserve_mem=12M:4096:trace trace_instance=boot_map@trace
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This will reserve 12 megabytes at boot up with a 4096 byte alignment
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and place the ring buffer in this memory. Note that due to KASLR, the
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memory may not be the same location each time, which will not preserve
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the buffer content.
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Also note that the layout of the ring buffer data may change between
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kernel versions where the validator will fail and reset the ring buffer
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if the layout is not the same as the previous kernel.
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If the ring buffer is used for persistent bootups and has events enabled,
|
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it is recommend to disable tracing so that events from a previous boot do not
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mix with events of the current boot (unless you are debugging a random crash
|
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at boot up).
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reserve_mem=12M:4096:trace trace_instance=boot_map^traceoff^traceprintk@trace,sched,irq
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See also Documentation/trace/debugging.rst
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trace_options=[option-list]
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[FTRACE] Enable or disable tracer options at boot.
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The option-list is a comma delimited list of options
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159
Documentation/trace/debugging.rst
Normal file
159
Documentation/trace/debugging.rst
Normal file
@ -0,0 +1,159 @@
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==============================
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Using the tracer for debugging
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==============================
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Copyright 2024 Google LLC.
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:Author: Steven Rostedt <rostedt@goodmis.org>
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:License: The GNU Free Documentation License, Version 1.2
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(dual licensed under the GPL v2)
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- Written for: 6.12
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Introduction
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------------
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The tracing infrastructure can be very useful for debugging the Linux
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kernel. This document is a place to add various methods of using the tracer
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for debugging.
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First, make sure that the tracefs file system is mounted::
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$ sudo mount -t tracefs tracefs /sys/kernel/tracing
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Using trace_printk()
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--------------------
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trace_printk() is a very lightweight utility that can be used in any context
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inside the kernel, with the exception of "noinstr" sections. It can be used
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in normal, softirq, interrupt and even NMI context. The trace data is
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written to the tracing ring buffer in a lockless way. To make it even
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lighter weight, when possible, it will only record the pointer to the format
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string, and save the raw arguments into the buffer. The format and the
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arguments will be post processed when the ring buffer is read. This way the
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trace_printk() format conversions are not done during the hot path, where
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the trace is being recorded.
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trace_printk() is meant only for debugging, and should never be added into
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a subsystem of the kernel. If you need debugging traces, add trace events
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instead. If a trace_printk() is found in the kernel, the following will
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appear in the dmesg::
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**********************************************************
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** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **
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** **
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** trace_printk() being used. Allocating extra memory. **
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** **
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** This means that this is a DEBUG kernel and it is **
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** unsafe for production use. **
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** **
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** If you see this message and you are not debugging **
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** the kernel, report this immediately to your vendor! **
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** **
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** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **
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**********************************************************
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Debugging kernel crashes
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------------------------
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There is various methods of acquiring the state of the system when a kernel
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crash occurs. This could be from the oops message in printk, or one could
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use kexec/kdump. But these just show what happened at the time of the crash.
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It can be very useful in knowing what happened up to the point of the crash.
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The tracing ring buffer, by default, is a circular buffer than will
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overwrite older events with newer ones. When a crash happens, the content of
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the ring buffer will be all the events that lead up to the crash.
|
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There are several kernel command line parameters that can be used to help in
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this. The first is "ftrace_dump_on_oops". This will dump the tracing ring
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buffer when a oops occurs to the console. This can be useful if the console
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is being logged somewhere. If a serial console is used, it may be prudent to
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make sure the ring buffer is relatively small, otherwise the dumping of the
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ring buffer may take several minutes to hours to finish. Here's an example
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of the kernel command line::
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ftrace_dump_on_oops trace_buf_size=50K
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Note, the tracing buffer is made up of per CPU buffers where each of these
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buffers is broken up into sub-buffers that are by default PAGE_SIZE. The
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above trace_buf_size option above sets each of the per CPU buffers to 50K,
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so, on a machine with 8 CPUs, that's actually 400K total.
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Persistent buffers across boots
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-------------------------------
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If the system memory allows it, the tracing ring buffer can be specified at
|
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a specific location in memory. If the location is the same across boots and
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the memory is not modified, the tracing buffer can be retrieved from the
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following boot. There's two ways to reserve memory for the use of the ring
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buffer.
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The more reliable way (on x86) is to reserve memory with the "memmap" kernel
|
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command line option and then use that memory for the trace_instance. This
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requires a bit of knowledge of the physical memory layout of the system. The
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advantage of using this method, is that the memory for the ring buffer will
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always be the same::
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memmap==12M$0x284500000 trace_instance=boot_map@0x284500000:12M
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The memmap above reserves 12 megabytes of memory at the physical memory
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location 0x284500000. Then the trace_instance option will create a trace
|
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instance "boot_map" at that same location with the same amount of memory
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reserved. As the ring buffer is broke up into per CPU buffers, the 12
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megabytes will be broken up evenly between those CPUs. If you have 8 CPUs,
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each per CPU ring buffer will be 1.5 megabytes in size. Note, that also
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includes meta data, so the amount of memory actually used by the ring buffer
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will be slightly smaller.
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Another more generic but less robust way to allocate a ring buffer mapping
|
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at boot is with the "reserve_mem" option::
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reserve_mem=12M:4096:trace trace_instance=boot_map@trace
|
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|
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The reserve_mem option above will find 12 megabytes that are available at
|
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boot up, and align it by 4096 bytes. It will label this memory as "trace"
|
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that can be used by later command line options.
|
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|
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The trace_instance option creates a "boot_map" instance and will use the
|
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memory reserved by reserve_mem that was labeled as "trace". This method is
|
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more generic but may not be as reliable. Due to KASLR, the memory reserved
|
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by reserve_mem may not be located at the same location. If this happens,
|
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then the ring buffer will not be from the previous boot and will be reset.
|
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|
||||
Sometimes, by using a larger alignment, it can keep KASLR from moving things
|
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around in such a way that it will move the location of the reserve_mem. By
|
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using a larger alignment, you may find better that the buffer is more
|
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consistent to where it is placed::
|
||||
|
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reserve_mem=12M:0x2000000:trace trace_instance=boot_map@trace
|
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|
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On boot up, the memory reserved for the ring buffer is validated. It will go
|
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through a series of tests to make sure that the ring buffer contains valid
|
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data. If it is, it will then set it up to be available to read from the
|
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instance. If it fails any of the tests, it will clear the entire ring buffer
|
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and initialize it as new.
|
||||
|
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The layout of this mapped memory may not be consistent from kernel to
|
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kernel, so only the same kernel is guaranteed to work if the mapping is
|
||||
preserved. Switching to a different kernel version may find a different
|
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layout and mark the buffer as invalid.
|
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|
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Using trace_printk() in the boot instance
|
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-----------------------------------------
|
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By default, the content of trace_printk() goes into the top level tracing
|
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instance. But this instance is never preserved across boots. To have the
|
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trace_printk() content, and some other internal tracing go to the preserved
|
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buffer (like dump stacks), either set the instance to be the trace_printk()
|
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destination from the kernel command line, or set it after boot up via the
|
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trace_printk_dest option.
|
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|
||||
After boot up::
|
||||
|
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echo 1 > /sys/kernel/tracing/instances/boot_map/options/trace_printk_dest
|
||||
|
||||
From the kernel command line::
|
||||
|
||||
reserve_mem=12M:4096:trace trace_instance=boot_map^traceprintk^traceoff@trace
|
||||
|
||||
If setting it from the kernel command line, it is recommended to also
|
||||
disable tracing with the "traceoff" flag, and enable tracing after boot up.
|
||||
Otherwise the trace from the most recent boot will be mixed with the trace
|
||||
from the previous boot, and may make it confusing to read.
|
||||
@ -1186,6 +1186,18 @@ Here are the available options:
|
||||
trace_printk
|
||||
Can disable trace_printk() from writing into the buffer.
|
||||
|
||||
trace_printk_dest
|
||||
Set to have trace_printk() and similar internal tracing functions
|
||||
write into this instance. Note, only one trace instance can have
|
||||
this set. By setting this flag, it clears the trace_printk_dest flag
|
||||
of the instance that had it set previously. By default, the top
|
||||
level trace has this set, and will get it set again if another
|
||||
instance has it set then clears it.
|
||||
|
||||
This flag cannot be cleared by the top level instance, as it is the
|
||||
default instance. The only way the top level instance has this flag
|
||||
cleared, is by it being set in another instance.
|
||||
|
||||
annotate
|
||||
It is sometimes confusing when the CPU buffers are full
|
||||
and one CPU buffer had a lot of events recently, thus
|
||||
|
||||
@ -89,6 +89,14 @@ void ring_buffer_discard_commit(struct trace_buffer *buffer,
|
||||
struct trace_buffer *
|
||||
__ring_buffer_alloc(unsigned long size, unsigned flags, struct lock_class_key *key);
|
||||
|
||||
struct trace_buffer *__ring_buffer_alloc_range(unsigned long size, unsigned flags,
|
||||
int order, unsigned long start,
|
||||
unsigned long range_size,
|
||||
struct lock_class_key *key);
|
||||
|
||||
bool ring_buffer_last_boot_delta(struct trace_buffer *buffer, long *text,
|
||||
long *data);
|
||||
|
||||
/*
|
||||
* Because the ring buffer is generic, if other users of the ring buffer get
|
||||
* traced by ftrace, it can produce lockdep warnings. We need to keep each
|
||||
@ -100,6 +108,18 @@ __ring_buffer_alloc(unsigned long size, unsigned flags, struct lock_class_key *k
|
||||
__ring_buffer_alloc((size), (flags), &__key); \
|
||||
})
|
||||
|
||||
/*
|
||||
* Because the ring buffer is generic, if other users of the ring buffer get
|
||||
* traced by ftrace, it can produce lockdep warnings. We need to keep each
|
||||
* ring buffer's lock class separate.
|
||||
*/
|
||||
#define ring_buffer_alloc_range(size, flags, order, start, range_size) \
|
||||
({ \
|
||||
static struct lock_class_key __key; \
|
||||
__ring_buffer_alloc_range((size), (flags), (order), (start), \
|
||||
(range_size), &__key); \
|
||||
})
|
||||
|
||||
typedef bool (*ring_buffer_cond_fn)(void *data);
|
||||
int ring_buffer_wait(struct trace_buffer *buffer, int cpu, int full,
|
||||
ring_buffer_cond_fn cond, void *data);
|
||||
|
||||
File diff suppressed because it is too large
Load Diff
@ -482,7 +482,7 @@ EXPORT_SYMBOL_GPL(unregister_ftrace_export);
|
||||
TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | \
|
||||
TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE | \
|
||||
TRACE_ITER_IRQ_INFO | TRACE_ITER_MARKERS | \
|
||||
TRACE_ITER_HASH_PTR)
|
||||
TRACE_ITER_HASH_PTR | TRACE_ITER_TRACE_PRINTK)
|
||||
|
||||
/* trace_options that are only supported by global_trace */
|
||||
#define TOP_LEVEL_TRACE_FLAGS (TRACE_ITER_PRINTK | \
|
||||
@ -490,7 +490,7 @@ EXPORT_SYMBOL_GPL(unregister_ftrace_export);
|
||||
|
||||
/* trace_flags that are default zero for instances */
|
||||
#define ZEROED_TRACE_FLAGS \
|
||||
(TRACE_ITER_EVENT_FORK | TRACE_ITER_FUNC_FORK)
|
||||
(TRACE_ITER_EVENT_FORK | TRACE_ITER_FUNC_FORK | TRACE_ITER_TRACE_PRINTK)
|
||||
|
||||
/*
|
||||
* The global_trace is the descriptor that holds the top-level tracing
|
||||
@ -500,6 +500,29 @@ static struct trace_array global_trace = {
|
||||
.trace_flags = TRACE_DEFAULT_FLAGS,
|
||||
};
|
||||
|
||||
static struct trace_array *printk_trace = &global_trace;
|
||||
|
||||
static __always_inline bool printk_binsafe(struct trace_array *tr)
|
||||
{
|
||||
/*
|
||||
* The binary format of traceprintk can cause a crash if used
|
||||
* by a buffer from another boot. Force the use of the
|
||||
* non binary version of trace_printk if the trace_printk
|
||||
* buffer is a boot mapped ring buffer.
|
||||
*/
|
||||
return !(tr->flags & TRACE_ARRAY_FL_BOOT);
|
||||
}
|
||||
|
||||
static void update_printk_trace(struct trace_array *tr)
|
||||
{
|
||||
if (printk_trace == tr)
|
||||
return;
|
||||
|
||||
printk_trace->trace_flags &= ~TRACE_ITER_TRACE_PRINTK;
|
||||
printk_trace = tr;
|
||||
tr->trace_flags |= TRACE_ITER_TRACE_PRINTK;
|
||||
}
|
||||
|
||||
void trace_set_ring_buffer_expanded(struct trace_array *tr)
|
||||
{
|
||||
if (!tr)
|
||||
@ -1117,7 +1140,7 @@ EXPORT_SYMBOL_GPL(__trace_array_puts);
|
||||
*/
|
||||
int __trace_puts(unsigned long ip, const char *str, int size)
|
||||
{
|
||||
return __trace_array_puts(&global_trace, ip, str, size);
|
||||
return __trace_array_puts(printk_trace, ip, str, size);
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(__trace_puts);
|
||||
|
||||
@ -1128,6 +1151,7 @@ EXPORT_SYMBOL_GPL(__trace_puts);
|
||||
*/
|
||||
int __trace_bputs(unsigned long ip, const char *str)
|
||||
{
|
||||
struct trace_array *tr = READ_ONCE(printk_trace);
|
||||
struct ring_buffer_event *event;
|
||||
struct trace_buffer *buffer;
|
||||
struct bputs_entry *entry;
|
||||
@ -1135,14 +1159,17 @@ int __trace_bputs(unsigned long ip, const char *str)
|
||||
int size = sizeof(struct bputs_entry);
|
||||
int ret = 0;
|
||||
|
||||
if (!(global_trace.trace_flags & TRACE_ITER_PRINTK))
|
||||
if (!printk_binsafe(tr))
|
||||
return __trace_puts(ip, str, strlen(str));
|
||||
|
||||
if (!(tr->trace_flags & TRACE_ITER_PRINTK))
|
||||
return 0;
|
||||
|
||||
if (unlikely(tracing_selftest_running || tracing_disabled))
|
||||
return 0;
|
||||
|
||||
trace_ctx = tracing_gen_ctx();
|
||||
buffer = global_trace.array_buffer.buffer;
|
||||
buffer = tr->array_buffer.buffer;
|
||||
|
||||
ring_buffer_nest_start(buffer);
|
||||
event = __trace_buffer_lock_reserve(buffer, TRACE_BPUTS, size,
|
||||
@ -1155,7 +1182,7 @@ int __trace_bputs(unsigned long ip, const char *str)
|
||||
entry->str = str;
|
||||
|
||||
__buffer_unlock_commit(buffer, event);
|
||||
ftrace_trace_stack(&global_trace, buffer, trace_ctx, 4, NULL);
|
||||
ftrace_trace_stack(tr, buffer, trace_ctx, 4, NULL);
|
||||
|
||||
ret = 1;
|
||||
out:
|
||||
@ -3021,7 +3048,7 @@ void trace_dump_stack(int skip)
|
||||
/* Skip 1 to skip this function. */
|
||||
skip++;
|
||||
#endif
|
||||
__ftrace_trace_stack(global_trace.array_buffer.buffer,
|
||||
__ftrace_trace_stack(printk_trace->array_buffer.buffer,
|
||||
tracing_gen_ctx(), skip, NULL);
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(trace_dump_stack);
|
||||
@ -3240,12 +3267,15 @@ int trace_vbprintk(unsigned long ip, const char *fmt, va_list args)
|
||||
struct trace_event_call *call = &event_bprint;
|
||||
struct ring_buffer_event *event;
|
||||
struct trace_buffer *buffer;
|
||||
struct trace_array *tr = &global_trace;
|
||||
struct trace_array *tr = READ_ONCE(printk_trace);
|
||||
struct bprint_entry *entry;
|
||||
unsigned int trace_ctx;
|
||||
char *tbuffer;
|
||||
int len = 0, size;
|
||||
|
||||
if (!printk_binsafe(tr))
|
||||
return trace_vprintk(ip, fmt, args);
|
||||
|
||||
if (unlikely(tracing_selftest_running || tracing_disabled))
|
||||
return 0;
|
||||
|
||||
@ -3338,7 +3368,7 @@ __trace_array_vprintk(struct trace_buffer *buffer,
|
||||
memcpy(&entry->buf, tbuffer, len + 1);
|
||||
if (!call_filter_check_discard(call, entry, buffer, event)) {
|
||||
__buffer_unlock_commit(buffer, event);
|
||||
ftrace_trace_stack(&global_trace, buffer, trace_ctx, 6, NULL);
|
||||
ftrace_trace_stack(printk_trace, buffer, trace_ctx, 6, NULL);
|
||||
}
|
||||
|
||||
out:
|
||||
@ -3434,7 +3464,7 @@ int trace_array_printk_buf(struct trace_buffer *buffer,
|
||||
int ret;
|
||||
va_list ap;
|
||||
|
||||
if (!(global_trace.trace_flags & TRACE_ITER_PRINTK))
|
||||
if (!(printk_trace->trace_flags & TRACE_ITER_PRINTK))
|
||||
return 0;
|
||||
|
||||
va_start(ap, fmt);
|
||||
@ -3446,7 +3476,7 @@ int trace_array_printk_buf(struct trace_buffer *buffer,
|
||||
__printf(2, 0)
|
||||
int trace_vprintk(unsigned long ip, const char *fmt, va_list args)
|
||||
{
|
||||
return trace_array_vprintk(&global_trace, ip, fmt, args);
|
||||
return trace_array_vprintk(printk_trace, ip, fmt, args);
|
||||
}
|
||||
EXPORT_SYMBOL_GPL(trace_vprintk);
|
||||
|
||||
@ -3667,8 +3697,11 @@ static void test_can_verify(void)
|
||||
void trace_check_vprintf(struct trace_iterator *iter, const char *fmt,
|
||||
va_list ap)
|
||||
{
|
||||
long text_delta = iter->tr->text_delta;
|
||||
long data_delta = iter->tr->data_delta;
|
||||
const char *p = fmt;
|
||||
const char *str;
|
||||
bool good;
|
||||
int i, j;
|
||||
|
||||
if (WARN_ON_ONCE(!fmt))
|
||||
@ -3687,7 +3720,10 @@ void trace_check_vprintf(struct trace_iterator *iter, const char *fmt,
|
||||
|
||||
j = 0;
|
||||
|
||||
/* We only care about %s and variants */
|
||||
/*
|
||||
* We only care about %s and variants
|
||||
* as well as %p[sS] if delta is non-zero
|
||||
*/
|
||||
for (i = 0; p[i]; i++) {
|
||||
if (i + 1 >= iter->fmt_size) {
|
||||
/*
|
||||
@ -3716,6 +3752,11 @@ void trace_check_vprintf(struct trace_iterator *iter, const char *fmt,
|
||||
}
|
||||
if (p[i+j] == 's')
|
||||
break;
|
||||
|
||||
if (text_delta && p[i+1] == 'p' &&
|
||||
((p[i+2] == 's' || p[i+2] == 'S')))
|
||||
break;
|
||||
|
||||
star = false;
|
||||
}
|
||||
j = 0;
|
||||
@ -3729,6 +3770,24 @@ void trace_check_vprintf(struct trace_iterator *iter, const char *fmt,
|
||||
iter->fmt[i] = '\0';
|
||||
trace_seq_vprintf(&iter->seq, iter->fmt, ap);
|
||||
|
||||
/* Add delta to %pS pointers */
|
||||
if (p[i+1] == 'p') {
|
||||
unsigned long addr;
|
||||
char fmt[4];
|
||||
|
||||
fmt[0] = '%';
|
||||
fmt[1] = 'p';
|
||||
fmt[2] = p[i+2]; /* Either %ps or %pS */
|
||||
fmt[3] = '\0';
|
||||
|
||||
addr = va_arg(ap, unsigned long);
|
||||
addr += text_delta;
|
||||
trace_seq_printf(&iter->seq, fmt, (void *)addr);
|
||||
|
||||
p += i + 3;
|
||||
continue;
|
||||
}
|
||||
|
||||
/*
|
||||
* If iter->seq is full, the above call no longer guarantees
|
||||
* that ap is in sync with fmt processing, and further calls
|
||||
@ -3747,6 +3806,14 @@ void trace_check_vprintf(struct trace_iterator *iter, const char *fmt,
|
||||
/* The ap now points to the string data of the %s */
|
||||
str = va_arg(ap, const char *);
|
||||
|
||||
good = trace_safe_str(iter, str, star, len);
|
||||
|
||||
/* Could be from the last boot */
|
||||
if (data_delta && !good) {
|
||||
str += data_delta;
|
||||
good = trace_safe_str(iter, str, star, len);
|
||||
}
|
||||
|
||||
/*
|
||||
* If you hit this warning, it is likely that the
|
||||
* trace event in question used %s on a string that
|
||||
@ -3756,8 +3823,7 @@ void trace_check_vprintf(struct trace_iterator *iter, const char *fmt,
|
||||
* instead. See samples/trace_events/trace-events-sample.h
|
||||
* for reference.
|
||||
*/
|
||||
if (WARN_ONCE(!trace_safe_str(iter, str, star, len),
|
||||
"fmt: '%s' current_buffer: '%s'",
|
||||
if (WARN_ONCE(!good, "fmt: '%s' current_buffer: '%s'",
|
||||
fmt, seq_buf_str(&iter->seq.seq))) {
|
||||
int ret;
|
||||
|
||||
@ -4919,6 +4985,11 @@ static int tracing_open(struct inode *inode, struct file *file)
|
||||
static bool
|
||||
trace_ok_for_array(struct tracer *t, struct trace_array *tr)
|
||||
{
|
||||
#ifdef CONFIG_TRACER_SNAPSHOT
|
||||
/* arrays with mapped buffer range do not have snapshots */
|
||||
if (tr->range_addr_start && t->use_max_tr)
|
||||
return false;
|
||||
#endif
|
||||
return (tr->flags & TRACE_ARRAY_FL_GLOBAL) || t->allow_instances;
|
||||
}
|
||||
|
||||
@ -5011,7 +5082,7 @@ static int show_traces_open(struct inode *inode, struct file *file)
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int show_traces_release(struct inode *inode, struct file *file)
|
||||
static int tracing_seq_release(struct inode *inode, struct file *file)
|
||||
{
|
||||
struct trace_array *tr = inode->i_private;
|
||||
|
||||
@ -5052,7 +5123,7 @@ static const struct file_operations show_traces_fops = {
|
||||
.open = show_traces_open,
|
||||
.read = seq_read,
|
||||
.llseek = seq_lseek,
|
||||
.release = show_traces_release,
|
||||
.release = tracing_seq_release,
|
||||
};
|
||||
|
||||
static ssize_t
|
||||
@ -5237,7 +5308,8 @@ int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set)
|
||||
int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled)
|
||||
{
|
||||
if ((mask == TRACE_ITER_RECORD_TGID) ||
|
||||
(mask == TRACE_ITER_RECORD_CMD))
|
||||
(mask == TRACE_ITER_RECORD_CMD) ||
|
||||
(mask == TRACE_ITER_TRACE_PRINTK))
|
||||
lockdep_assert_held(&event_mutex);
|
||||
|
||||
/* do nothing if flag is already set */
|
||||
@ -5249,6 +5321,25 @@ int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled)
|
||||
if (tr->current_trace->flag_changed(tr, mask, !!enabled))
|
||||
return -EINVAL;
|
||||
|
||||
if (mask == TRACE_ITER_TRACE_PRINTK) {
|
||||
if (enabled) {
|
||||
update_printk_trace(tr);
|
||||
} else {
|
||||
/*
|
||||
* The global_trace cannot clear this.
|
||||
* It's flag only gets cleared if another instance sets it.
|
||||
*/
|
||||
if (printk_trace == &global_trace)
|
||||
return -EINVAL;
|
||||
/*
|
||||
* An instance must always have it set.
|
||||
* by default, that's the global_trace instane.
|
||||
*/
|
||||
if (printk_trace == tr)
|
||||
update_printk_trace(&global_trace);
|
||||
}
|
||||
}
|
||||
|
||||
if (enabled)
|
||||
tr->trace_flags |= mask;
|
||||
else
|
||||
@ -6034,6 +6125,18 @@ ssize_t tracing_resize_ring_buffer(struct trace_array *tr,
|
||||
return ret;
|
||||
}
|
||||
|
||||
static void update_last_data(struct trace_array *tr)
|
||||
{
|
||||
if (!tr->text_delta && !tr->data_delta)
|
||||
return;
|
||||
|
||||
/* Clear old data */
|
||||
tracing_reset_online_cpus(&tr->array_buffer);
|
||||
|
||||
/* Using current data now */
|
||||
tr->text_delta = 0;
|
||||
tr->data_delta = 0;
|
||||
}
|
||||
|
||||
/**
|
||||
* tracing_update_buffers - used by tracing facility to expand ring buffers
|
||||
@ -6051,6 +6154,9 @@ int tracing_update_buffers(struct trace_array *tr)
|
||||
int ret = 0;
|
||||
|
||||
mutex_lock(&trace_types_lock);
|
||||
|
||||
update_last_data(tr);
|
||||
|
||||
if (!tr->ring_buffer_expanded)
|
||||
ret = __tracing_resize_ring_buffer(tr, trace_buf_size,
|
||||
RING_BUFFER_ALL_CPUS);
|
||||
@ -6106,6 +6212,8 @@ int tracing_set_tracer(struct trace_array *tr, const char *buf)
|
||||
|
||||
mutex_lock(&trace_types_lock);
|
||||
|
||||
update_last_data(tr);
|
||||
|
||||
if (!tr->ring_buffer_expanded) {
|
||||
ret = __tracing_resize_ring_buffer(tr, trace_buf_size,
|
||||
RING_BUFFER_ALL_CPUS);
|
||||
@ -6853,6 +6961,37 @@ tracing_total_entries_read(struct file *filp, char __user *ubuf,
|
||||
return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
|
||||
}
|
||||
|
||||
static ssize_t
|
||||
tracing_last_boot_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos)
|
||||
{
|
||||
struct trace_array *tr = filp->private_data;
|
||||
struct seq_buf seq;
|
||||
char buf[64];
|
||||
|
||||
seq_buf_init(&seq, buf, 64);
|
||||
|
||||
seq_buf_printf(&seq, "text delta:\t%ld\n", tr->text_delta);
|
||||
seq_buf_printf(&seq, "data delta:\t%ld\n", tr->data_delta);
|
||||
|
||||
return simple_read_from_buffer(ubuf, cnt, ppos, buf, seq_buf_used(&seq));
|
||||
}
|
||||
|
||||
static int tracing_buffer_meta_open(struct inode *inode, struct file *filp)
|
||||
{
|
||||
struct trace_array *tr = inode->i_private;
|
||||
int cpu = tracing_get_cpu(inode);
|
||||
int ret;
|
||||
|
||||
ret = tracing_check_open_get_tr(tr);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
ret = ring_buffer_meta_seq_init(filp, tr->array_buffer.buffer, cpu);
|
||||
if (ret < 0)
|
||||
__trace_array_put(tr);
|
||||
return ret;
|
||||
}
|
||||
|
||||
static ssize_t
|
||||
tracing_free_buffer_write(struct file *filp, const char __user *ubuf,
|
||||
size_t cnt, loff_t *ppos)
|
||||
@ -7429,6 +7568,13 @@ static const struct file_operations tracing_entries_fops = {
|
||||
.release = tracing_release_generic_tr,
|
||||
};
|
||||
|
||||
static const struct file_operations tracing_buffer_meta_fops = {
|
||||
.open = tracing_buffer_meta_open,
|
||||
.read = seq_read,
|
||||
.llseek = seq_lseek,
|
||||
.release = tracing_seq_release,
|
||||
};
|
||||
|
||||
static const struct file_operations tracing_total_entries_fops = {
|
||||
.open = tracing_open_generic_tr,
|
||||
.read = tracing_total_entries_read,
|
||||
@ -7469,6 +7615,13 @@ static const struct file_operations trace_time_stamp_mode_fops = {
|
||||
.release = tracing_single_release_tr,
|
||||
};
|
||||
|
||||
static const struct file_operations last_boot_fops = {
|
||||
.open = tracing_open_generic_tr,
|
||||
.read = tracing_last_boot_read,
|
||||
.llseek = generic_file_llseek,
|
||||
.release = tracing_release_generic_tr,
|
||||
};
|
||||
|
||||
#ifdef CONFIG_TRACER_SNAPSHOT
|
||||
static const struct file_operations snapshot_fops = {
|
||||
.open = tracing_snapshot_open,
|
||||
@ -8661,12 +8814,17 @@ tracing_init_tracefs_percpu(struct trace_array *tr, long cpu)
|
||||
trace_create_cpu_file("buffer_size_kb", TRACE_MODE_READ, d_cpu,
|
||||
tr, cpu, &tracing_entries_fops);
|
||||
|
||||
if (tr->range_addr_start)
|
||||
trace_create_cpu_file("buffer_meta", TRACE_MODE_READ, d_cpu,
|
||||
tr, cpu, &tracing_buffer_meta_fops);
|
||||
#ifdef CONFIG_TRACER_SNAPSHOT
|
||||
trace_create_cpu_file("snapshot", TRACE_MODE_WRITE, d_cpu,
|
||||
tr, cpu, &snapshot_fops);
|
||||
if (!tr->range_addr_start) {
|
||||
trace_create_cpu_file("snapshot", TRACE_MODE_WRITE, d_cpu,
|
||||
tr, cpu, &snapshot_fops);
|
||||
|
||||
trace_create_cpu_file("snapshot_raw", TRACE_MODE_READ, d_cpu,
|
||||
tr, cpu, &snapshot_raw_fops);
|
||||
trace_create_cpu_file("snapshot_raw", TRACE_MODE_READ, d_cpu,
|
||||
tr, cpu, &snapshot_raw_fops);
|
||||
}
|
||||
#endif
|
||||
}
|
||||
|
||||
@ -9203,7 +9361,21 @@ allocate_trace_buffer(struct trace_array *tr, struct array_buffer *buf, int size
|
||||
|
||||
buf->tr = tr;
|
||||
|
||||
buf->buffer = ring_buffer_alloc(size, rb_flags);
|
||||
if (tr->range_addr_start && tr->range_addr_size) {
|
||||
buf->buffer = ring_buffer_alloc_range(size, rb_flags, 0,
|
||||
tr->range_addr_start,
|
||||
tr->range_addr_size);
|
||||
|
||||
ring_buffer_last_boot_delta(buf->buffer,
|
||||
&tr->text_delta, &tr->data_delta);
|
||||
/*
|
||||
* This is basically the same as a mapped buffer,
|
||||
* with the same restrictions.
|
||||
*/
|
||||
tr->mapped++;
|
||||
} else {
|
||||
buf->buffer = ring_buffer_alloc(size, rb_flags);
|
||||
}
|
||||
if (!buf->buffer)
|
||||
return -ENOMEM;
|
||||
|
||||
@ -9240,6 +9412,10 @@ static int allocate_trace_buffers(struct trace_array *tr, int size)
|
||||
return ret;
|
||||
|
||||
#ifdef CONFIG_TRACER_MAX_TRACE
|
||||
/* Fix mapped buffer trace arrays do not have snapshot buffers */
|
||||
if (tr->range_addr_start)
|
||||
return 0;
|
||||
|
||||
ret = allocate_trace_buffer(tr, &tr->max_buffer,
|
||||
allocate_snapshot ? size : 1);
|
||||
if (MEM_FAIL(ret, "Failed to allocate trace buffer\n")) {
|
||||
@ -9340,7 +9516,9 @@ static int trace_array_create_dir(struct trace_array *tr)
|
||||
}
|
||||
|
||||
static struct trace_array *
|
||||
trace_array_create_systems(const char *name, const char *systems)
|
||||
trace_array_create_systems(const char *name, const char *systems,
|
||||
unsigned long range_addr_start,
|
||||
unsigned long range_addr_size)
|
||||
{
|
||||
struct trace_array *tr;
|
||||
int ret;
|
||||
@ -9366,6 +9544,10 @@ trace_array_create_systems(const char *name, const char *systems)
|
||||
goto out_free_tr;
|
||||
}
|
||||
|
||||
/* Only for boot up memory mapped ring buffers */
|
||||
tr->range_addr_start = range_addr_start;
|
||||
tr->range_addr_size = range_addr_size;
|
||||
|
||||
tr->trace_flags = global_trace.trace_flags & ~ZEROED_TRACE_FLAGS;
|
||||
|
||||
cpumask_copy(tr->tracing_cpumask, cpu_all_mask);
|
||||
@ -9423,7 +9605,7 @@ trace_array_create_systems(const char *name, const char *systems)
|
||||
|
||||
static struct trace_array *trace_array_create(const char *name)
|
||||
{
|
||||
return trace_array_create_systems(name, NULL);
|
||||
return trace_array_create_systems(name, NULL, 0, 0);
|
||||
}
|
||||
|
||||
static int instance_mkdir(const char *name)
|
||||
@ -9448,6 +9630,31 @@ static int instance_mkdir(const char *name)
|
||||
return ret;
|
||||
}
|
||||
|
||||
static u64 map_pages(u64 start, u64 size)
|
||||
{
|
||||
struct page **pages;
|
||||
phys_addr_t page_start;
|
||||
unsigned int page_count;
|
||||
unsigned int i;
|
||||
void *vaddr;
|
||||
|
||||
page_count = DIV_ROUND_UP(size, PAGE_SIZE);
|
||||
|
||||
page_start = start;
|
||||
pages = kmalloc_array(page_count, sizeof(struct page *), GFP_KERNEL);
|
||||
if (!pages)
|
||||
return 0;
|
||||
|
||||
for (i = 0; i < page_count; i++) {
|
||||
phys_addr_t addr = page_start + i * PAGE_SIZE;
|
||||
pages[i] = pfn_to_page(addr >> PAGE_SHIFT);
|
||||
}
|
||||
vaddr = vmap(pages, page_count, VM_MAP, PAGE_KERNEL);
|
||||
kfree(pages);
|
||||
|
||||
return (u64)(unsigned long)vaddr;
|
||||
}
|
||||
|
||||
/**
|
||||
* trace_array_get_by_name - Create/Lookup a trace array, given its name.
|
||||
* @name: The name of the trace array to be looked up/created.
|
||||
@ -9477,7 +9684,7 @@ struct trace_array *trace_array_get_by_name(const char *name, const char *system
|
||||
goto out_unlock;
|
||||
}
|
||||
|
||||
tr = trace_array_create_systems(name, systems);
|
||||
tr = trace_array_create_systems(name, systems, 0, 0);
|
||||
|
||||
if (IS_ERR(tr))
|
||||
tr = NULL;
|
||||
@ -9507,6 +9714,9 @@ static int __remove_instance(struct trace_array *tr)
|
||||
set_tracer_flag(tr, 1 << i, 0);
|
||||
}
|
||||
|
||||
if (printk_trace == tr)
|
||||
update_printk_trace(&global_trace);
|
||||
|
||||
tracing_set_nop(tr);
|
||||
clear_ftrace_function_probes(tr);
|
||||
event_trace_del_tracer(tr);
|
||||
@ -9669,10 +9879,15 @@ init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer)
|
||||
if (ftrace_create_function_files(tr, d_tracer))
|
||||
MEM_FAIL(1, "Could not allocate function filter files");
|
||||
|
||||
if (tr->range_addr_start) {
|
||||
trace_create_file("last_boot_info", TRACE_MODE_READ, d_tracer,
|
||||
tr, &last_boot_fops);
|
||||
#ifdef CONFIG_TRACER_SNAPSHOT
|
||||
trace_create_file("snapshot", TRACE_MODE_WRITE, d_tracer,
|
||||
tr, &snapshot_fops);
|
||||
} else {
|
||||
trace_create_file("snapshot", TRACE_MODE_WRITE, d_tracer,
|
||||
tr, &snapshot_fops);
|
||||
#endif
|
||||
}
|
||||
|
||||
trace_create_file("error_log", TRACE_MODE_WRITE, d_tracer,
|
||||
tr, &tracing_err_log_fops);
|
||||
@ -10292,6 +10507,7 @@ __init static void enable_instances(void)
|
||||
{
|
||||
struct trace_array *tr;
|
||||
char *curr_str;
|
||||
char *name;
|
||||
char *str;
|
||||
char *tok;
|
||||
|
||||
@ -10300,19 +10516,107 @@ __init static void enable_instances(void)
|
||||
str = boot_instance_info;
|
||||
|
||||
while ((curr_str = strsep(&str, "\t"))) {
|
||||
phys_addr_t start = 0;
|
||||
phys_addr_t size = 0;
|
||||
unsigned long addr = 0;
|
||||
bool traceprintk = false;
|
||||
bool traceoff = false;
|
||||
char *flag_delim;
|
||||
char *addr_delim;
|
||||
|
||||
tok = strsep(&curr_str, ",");
|
||||
|
||||
if (IS_ENABLED(CONFIG_TRACER_MAX_TRACE))
|
||||
do_allocate_snapshot(tok);
|
||||
flag_delim = strchr(tok, '^');
|
||||
addr_delim = strchr(tok, '@');
|
||||
|
||||
tr = trace_array_get_by_name(tok, NULL);
|
||||
if (!tr) {
|
||||
pr_warn("Failed to create instance buffer %s\n", curr_str);
|
||||
if (addr_delim)
|
||||
*addr_delim++ = '\0';
|
||||
|
||||
if (flag_delim)
|
||||
*flag_delim++ = '\0';
|
||||
|
||||
name = tok;
|
||||
|
||||
if (flag_delim) {
|
||||
char *flag;
|
||||
|
||||
while ((flag = strsep(&flag_delim, "^"))) {
|
||||
if (strcmp(flag, "traceoff") == 0) {
|
||||
traceoff = true;
|
||||
} else if ((strcmp(flag, "printk") == 0) ||
|
||||
(strcmp(flag, "traceprintk") == 0) ||
|
||||
(strcmp(flag, "trace_printk") == 0)) {
|
||||
traceprintk = true;
|
||||
} else {
|
||||
pr_info("Tracing: Invalid instance flag '%s' for %s\n",
|
||||
flag, name);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
tok = addr_delim;
|
||||
if (tok && isdigit(*tok)) {
|
||||
start = memparse(tok, &tok);
|
||||
if (!start) {
|
||||
pr_warn("Tracing: Invalid boot instance address for %s\n",
|
||||
name);
|
||||
continue;
|
||||
}
|
||||
if (*tok != ':') {
|
||||
pr_warn("Tracing: No size specified for instance %s\n", name);
|
||||
continue;
|
||||
}
|
||||
tok++;
|
||||
size = memparse(tok, &tok);
|
||||
if (!size) {
|
||||
pr_warn("Tracing: Invalid boot instance size for %s\n",
|
||||
name);
|
||||
continue;
|
||||
}
|
||||
} else if (tok) {
|
||||
if (!reserve_mem_find_by_name(tok, &start, &size)) {
|
||||
start = 0;
|
||||
pr_warn("Failed to map boot instance %s to %s\n", name, tok);
|
||||
continue;
|
||||
}
|
||||
}
|
||||
|
||||
if (start) {
|
||||
addr = map_pages(start, size);
|
||||
if (addr) {
|
||||
pr_info("Tracing: mapped boot instance %s at physical memory %pa of size 0x%lx\n",
|
||||
name, &start, (unsigned long)size);
|
||||
} else {
|
||||
pr_warn("Tracing: Failed to map boot instance %s\n", name);
|
||||
continue;
|
||||
}
|
||||
} else {
|
||||
/* Only non mapped buffers have snapshot buffers */
|
||||
if (IS_ENABLED(CONFIG_TRACER_MAX_TRACE))
|
||||
do_allocate_snapshot(name);
|
||||
}
|
||||
|
||||
tr = trace_array_create_systems(name, NULL, addr, size);
|
||||
if (IS_ERR(tr)) {
|
||||
pr_warn("Tracing: Failed to create instance buffer %s\n", curr_str);
|
||||
continue;
|
||||
}
|
||||
/* Allow user space to delete it */
|
||||
trace_array_put(tr);
|
||||
|
||||
if (traceoff)
|
||||
tracer_tracing_off(tr);
|
||||
|
||||
if (traceprintk)
|
||||
update_printk_trace(tr);
|
||||
|
||||
/*
|
||||
* If start is set, then this is a mapped buffer, and
|
||||
* cannot be deleted by user space, so keep the reference
|
||||
* to it.
|
||||
*/
|
||||
if (start)
|
||||
tr->flags |= TRACE_ARRAY_FL_BOOT;
|
||||
else
|
||||
trace_array_put(tr);
|
||||
|
||||
while ((tok = strsep(&curr_str, ","))) {
|
||||
early_enable_events(tr, tok, true);
|
||||
|
||||
@ -336,7 +336,6 @@ struct trace_array {
|
||||
bool allocated_snapshot;
|
||||
spinlock_t snapshot_trigger_lock;
|
||||
unsigned int snapshot;
|
||||
unsigned int mapped;
|
||||
unsigned long max_latency;
|
||||
#ifdef CONFIG_FSNOTIFY
|
||||
struct dentry *d_max_latency;
|
||||
@ -344,6 +343,13 @@ struct trace_array {
|
||||
struct irq_work fsnotify_irqwork;
|
||||
#endif
|
||||
#endif
|
||||
/* The below is for memory mapped ring buffer */
|
||||
unsigned int mapped;
|
||||
unsigned long range_addr_start;
|
||||
unsigned long range_addr_size;
|
||||
long text_delta;
|
||||
long data_delta;
|
||||
|
||||
struct trace_pid_list __rcu *filtered_pids;
|
||||
struct trace_pid_list __rcu *filtered_no_pids;
|
||||
/*
|
||||
@ -423,7 +429,8 @@ struct trace_array {
|
||||
};
|
||||
|
||||
enum {
|
||||
TRACE_ARRAY_FL_GLOBAL = (1 << 0)
|
||||
TRACE_ARRAY_FL_GLOBAL = BIT(0),
|
||||
TRACE_ARRAY_FL_BOOT = BIT(1),
|
||||
};
|
||||
|
||||
extern struct list_head ftrace_trace_arrays;
|
||||
@ -644,6 +651,8 @@ trace_buffer_lock_reserve(struct trace_buffer *buffer,
|
||||
unsigned long len,
|
||||
unsigned int trace_ctx);
|
||||
|
||||
int ring_buffer_meta_seq_init(struct file *file, struct trace_buffer *buffer, int cpu);
|
||||
|
||||
struct trace_entry *tracing_get_trace_entry(struct trace_array *tr,
|
||||
struct trace_array_cpu *data);
|
||||
|
||||
@ -1312,6 +1321,7 @@ extern int trace_get_user(struct trace_parser *parser, const char __user *ubuf,
|
||||
C(IRQ_INFO, "irq-info"), \
|
||||
C(MARKERS, "markers"), \
|
||||
C(EVENT_FORK, "event-fork"), \
|
||||
C(TRACE_PRINTK, "trace_printk_dest"), \
|
||||
C(PAUSE_ON_TRACE, "pause-on-trace"), \
|
||||
C(HASH_PTR, "hash-ptr"), /* Print hashed pointer */ \
|
||||
FUNCTION_FLAGS \
|
||||
|
||||
@ -544,6 +544,8 @@ print_graph_irq(struct trace_iterator *iter, unsigned long addr,
|
||||
struct trace_seq *s = &iter->seq;
|
||||
struct trace_entry *ent = iter->ent;
|
||||
|
||||
addr += iter->tr->text_delta;
|
||||
|
||||
if (addr < (unsigned long)__irqentry_text_start ||
|
||||
addr >= (unsigned long)__irqentry_text_end)
|
||||
return;
|
||||
@ -710,6 +712,7 @@ print_graph_entry_leaf(struct trace_iterator *iter,
|
||||
struct ftrace_graph_ret *graph_ret;
|
||||
struct ftrace_graph_ent *call;
|
||||
unsigned long long duration;
|
||||
unsigned long func;
|
||||
int cpu = iter->cpu;
|
||||
int i;
|
||||
|
||||
@ -717,6 +720,8 @@ print_graph_entry_leaf(struct trace_iterator *iter,
|
||||
call = &entry->graph_ent;
|
||||
duration = graph_ret->rettime - graph_ret->calltime;
|
||||
|
||||
func = call->func + iter->tr->text_delta;
|
||||
|
||||
if (data) {
|
||||
struct fgraph_cpu_data *cpu_data;
|
||||
|
||||
@ -747,10 +752,10 @@ print_graph_entry_leaf(struct trace_iterator *iter,
|
||||
* enabled.
|
||||
*/
|
||||
if (flags & __TRACE_GRAPH_PRINT_RETVAL)
|
||||
print_graph_retval(s, graph_ret->retval, true, (void *)call->func,
|
||||
print_graph_retval(s, graph_ret->retval, true, (void *)func,
|
||||
!!(flags & TRACE_GRAPH_PRINT_RETVAL_HEX));
|
||||
else
|
||||
trace_seq_printf(s, "%ps();\n", (void *)call->func);
|
||||
trace_seq_printf(s, "%ps();\n", (void *)func);
|
||||
|
||||
print_graph_irq(iter, graph_ret->func, TRACE_GRAPH_RET,
|
||||
cpu, iter->ent->pid, flags);
|
||||
@ -766,6 +771,7 @@ print_graph_entry_nested(struct trace_iterator *iter,
|
||||
struct ftrace_graph_ent *call = &entry->graph_ent;
|
||||
struct fgraph_data *data = iter->private;
|
||||
struct trace_array *tr = iter->tr;
|
||||
unsigned long func;
|
||||
int i;
|
||||
|
||||
if (data) {
|
||||
@ -788,7 +794,9 @@ print_graph_entry_nested(struct trace_iterator *iter,
|
||||
for (i = 0; i < call->depth * TRACE_GRAPH_INDENT; i++)
|
||||
trace_seq_putc(s, ' ');
|
||||
|
||||
trace_seq_printf(s, "%ps() {\n", (void *)call->func);
|
||||
func = call->func + iter->tr->text_delta;
|
||||
|
||||
trace_seq_printf(s, "%ps() {\n", (void *)func);
|
||||
|
||||
if (trace_seq_has_overflowed(s))
|
||||
return TRACE_TYPE_PARTIAL_LINE;
|
||||
@ -863,6 +871,8 @@ check_irq_entry(struct trace_iterator *iter, u32 flags,
|
||||
int *depth_irq;
|
||||
struct fgraph_data *data = iter->private;
|
||||
|
||||
addr += iter->tr->text_delta;
|
||||
|
||||
/*
|
||||
* If we are either displaying irqs, or we got called as
|
||||
* a graph event and private data does not exist,
|
||||
@ -990,11 +1000,14 @@ print_graph_return(struct ftrace_graph_ret *trace, struct trace_seq *s,
|
||||
unsigned long long duration = trace->rettime - trace->calltime;
|
||||
struct fgraph_data *data = iter->private;
|
||||
struct trace_array *tr = iter->tr;
|
||||
unsigned long func;
|
||||
pid_t pid = ent->pid;
|
||||
int cpu = iter->cpu;
|
||||
int func_match = 1;
|
||||
int i;
|
||||
|
||||
func = trace->func + iter->tr->text_delta;
|
||||
|
||||
if (check_irq_return(iter, flags, trace->depth))
|
||||
return TRACE_TYPE_HANDLED;
|
||||
|
||||
@ -1033,7 +1046,7 @@ print_graph_return(struct ftrace_graph_ret *trace, struct trace_seq *s,
|
||||
* function-retval option is enabled.
|
||||
*/
|
||||
if (flags & __TRACE_GRAPH_PRINT_RETVAL) {
|
||||
print_graph_retval(s, trace->retval, false, (void *)trace->func,
|
||||
print_graph_retval(s, trace->retval, false, (void *)func,
|
||||
!!(flags & TRACE_GRAPH_PRINT_RETVAL_HEX));
|
||||
} else {
|
||||
/*
|
||||
@ -1046,7 +1059,7 @@ print_graph_return(struct ftrace_graph_ret *trace, struct trace_seq *s,
|
||||
if (func_match && !(flags & TRACE_GRAPH_PRINT_TAIL))
|
||||
trace_seq_puts(s, "}\n");
|
||||
else
|
||||
trace_seq_printf(s, "} /* %ps */\n", (void *)trace->func);
|
||||
trace_seq_printf(s, "} /* %ps */\n", (void *)func);
|
||||
}
|
||||
|
||||
/* Overrun */
|
||||
|
||||
@ -990,8 +990,11 @@ enum print_line_t trace_nop_print(struct trace_iterator *iter, int flags,
|
||||
}
|
||||
|
||||
static void print_fn_trace(struct trace_seq *s, unsigned long ip,
|
||||
unsigned long parent_ip, int flags)
|
||||
unsigned long parent_ip, long delta, int flags)
|
||||
{
|
||||
ip += delta;
|
||||
parent_ip += delta;
|
||||
|
||||
seq_print_ip_sym(s, ip, flags);
|
||||
|
||||
if ((flags & TRACE_ITER_PRINT_PARENT) && parent_ip) {
|
||||
@ -1009,7 +1012,7 @@ static enum print_line_t trace_fn_trace(struct trace_iterator *iter, int flags,
|
||||
|
||||
trace_assign_type(field, iter->ent);
|
||||
|
||||
print_fn_trace(s, field->ip, field->parent_ip, flags);
|
||||
print_fn_trace(s, field->ip, field->parent_ip, iter->tr->text_delta, flags);
|
||||
trace_seq_putc(s, '\n');
|
||||
|
||||
return trace_handle_return(s);
|
||||
@ -1230,6 +1233,7 @@ static enum print_line_t trace_stack_print(struct trace_iterator *iter,
|
||||
struct trace_seq *s = &iter->seq;
|
||||
unsigned long *p;
|
||||
unsigned long *end;
|
||||
long delta = iter->tr->text_delta;
|
||||
|
||||
trace_assign_type(field, iter->ent);
|
||||
end = (unsigned long *)((long)iter->ent + iter->ent_size);
|
||||
@ -1242,7 +1246,7 @@ static enum print_line_t trace_stack_print(struct trace_iterator *iter,
|
||||
break;
|
||||
|
||||
trace_seq_puts(s, " => ");
|
||||
seq_print_ip_sym(s, *p, flags);
|
||||
seq_print_ip_sym(s, (*p) + delta, flags);
|
||||
trace_seq_putc(s, '\n');
|
||||
}
|
||||
|
||||
@ -1587,10 +1591,13 @@ static enum print_line_t trace_print_print(struct trace_iterator *iter,
|
||||
{
|
||||
struct print_entry *field;
|
||||
struct trace_seq *s = &iter->seq;
|
||||
unsigned long ip;
|
||||
|
||||
trace_assign_type(field, iter->ent);
|
||||
|
||||
seq_print_ip_sym(s, field->ip, flags);
|
||||
ip = field->ip + iter->tr->text_delta;
|
||||
|
||||
seq_print_ip_sym(s, ip, flags);
|
||||
trace_seq_printf(s, ": %s", field->buf);
|
||||
|
||||
return trace_handle_return(s);
|
||||
@ -1674,7 +1681,7 @@ trace_func_repeats_print(struct trace_iterator *iter, int flags,
|
||||
|
||||
trace_assign_type(field, iter->ent);
|
||||
|
||||
print_fn_trace(s, field->ip, field->parent_ip, flags);
|
||||
print_fn_trace(s, field->ip, field->parent_ip, iter->tr->text_delta, flags);
|
||||
trace_seq_printf(s, " (repeats: %u, last_ts:", field->count);
|
||||
trace_print_time(s, iter,
|
||||
iter->ts - FUNC_REPEATS_GET_DELTA_TS(field));
|
||||
|
||||
@ -92,12 +92,22 @@ int tracefs_cpu_map(struct tracefs_cpu_map_desc *desc, int cpu)
|
||||
if (desc->cpu_fd < 0)
|
||||
return -ENODEV;
|
||||
|
||||
again:
|
||||
map = mmap(NULL, page_size, PROT_READ, MAP_SHARED, desc->cpu_fd, 0);
|
||||
if (map == MAP_FAILED)
|
||||
return -errno;
|
||||
|
||||
desc->meta = (struct trace_buffer_meta *)map;
|
||||
|
||||
/* the meta-page is bigger than the original mapping */
|
||||
if (page_size < desc->meta->meta_struct_len) {
|
||||
int meta_page_size = desc->meta->meta_page_size;
|
||||
|
||||
munmap(desc->meta, page_size);
|
||||
page_size = meta_page_size;
|
||||
goto again;
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
@ -228,6 +238,20 @@ TEST_F(map, data_mmap)
|
||||
data = mmap(NULL, data_len, PROT_READ, MAP_SHARED,
|
||||
desc->cpu_fd, meta_len);
|
||||
ASSERT_EQ(data, MAP_FAILED);
|
||||
|
||||
/* Verify meta-page padding */
|
||||
if (desc->meta->meta_page_size > getpagesize()) {
|
||||
data_len = desc->meta->meta_page_size;
|
||||
data = mmap(NULL, data_len,
|
||||
PROT_READ, MAP_SHARED, desc->cpu_fd, 0);
|
||||
ASSERT_NE(data, MAP_FAILED);
|
||||
|
||||
for (int i = desc->meta->meta_struct_len;
|
||||
i < desc->meta->meta_page_size; i += sizeof(int))
|
||||
ASSERT_EQ(*(int *)(data + i), 0);
|
||||
|
||||
munmap(data, data_len);
|
||||
}
|
||||
}
|
||||
|
||||
FIXTURE(snapshot) {
|
||||
|
||||
Loading…
Reference in New Issue
Block a user