Based on the following two reasones, we could simplify the calculation:
- If the number after roundup count is not power of 2, we would
definitely have more than 1 empty page with a higher order.
- get_count_order() just return current order, so one lower order
could meet the requirement.
The calculation could be simplified by lower one order level when pages
are not power of 2.
Link: https://lkml.kernel.org/r/20200831031104.23322-5-richard.weiyang@linux.alibaba.com
Signed-off-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
No need to add a check to subtract the number of bits if bits is zero after
fls(). Just divide the size by two before calling it. This does give the
same answer for size of 0 and 1, but that's fine.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
When CONFIG_NET is not defined, I hit the following build error:
kernel/trace/bpf_trace.o:(.rodata+0x110): undefined reference to `bpf_prog_test_run_raw_tp'
Commit 1b4d60ec16 ("bpf: Enable BPF_PROG_TEST_RUN for raw_tracepoint")
added test_run support for raw_tracepoint in /kernel/trace/bpf_trace.c.
But the test_run function bpf_prog_test_run_raw_tp is defined in
net/bpf/test_run.c, only available with CONFIG_NET=y.
Adding a CONFIG_NET guard for
.test_run = bpf_prog_test_run_raw_tp;
fixed the above build issue.
Fixes: 1b4d60ec16 ("bpf: Enable BPF_PROG_TEST_RUN for raw_tracepoint")
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201007062933.3425899-1-yhs@fb.com
Rejecting non-native endian BTF overlapped with the addition
of support for it.
The rest were more simple overlapping changes, except the
renesas ravb binding update, which had to follow a file
move as well as a YAML conversion.
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently, sythetic events only support static string fields such as:
# echo 'test_latency u64 lat; char somename[32]' > /sys/kernel/debug/tracing/synthetic_events
Which is fine, but wastes a lot of space in the event.
It also prevents the most commonly-defined strings in the existing
trace events e.g. those defined using __string(), from being passed to
synthetic events via the trace() action.
With this change, synthetic events with dynamic fields can be defined:
# echo 'test_latency u64 lat; char somename[]' > /sys/kernel/debug/tracing/synthetic_events
And the trace() action can be used to generate events using either
dynamic or static strings:
# echo 'hist:keys=name:lat=common_timestamp.usecs-$ts0:onmatch(sys.event).test_latency($lat,name)' > /sys/kernel/debug/tracing/events
The synthetic event dynamic strings are implemented in the same way as
the existing __data_loc strings and appear as such in the format file.
[ <rostedt@goodmis.org>: added __set_synth_event_print_fmt() changes:
I added the following to make it work with trace-cmd. Dynamic strings
must have __get_str() for events in the print_fmt otherwise it can't be
parsed correctly. ]
Link: https://lore.kernel.org/r/cover.1601588066.git.zanussi@kernel.org
Link: https://lkml.kernel.org/r/3ed35b6d0e390f5b94cb4a9ba1cc18f5982ab277.1601848695.git.zanussi@kernel.org
Tested-by: Axel Rasmussen <axelrasmussen@google.com>
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
String variables created as field variables and save variables are
already handled properly by having their values copied when set. The
same isn't done for normal variables, but needs to be - simply saving
a pointer to a string contained in an old event isn't sufficient,
since that event's data may quickly become overwritten and therefore a
string pointer to it could yield garbage.
This change uses the same mechanism as field variables and simply
appends the new strings to the existing per-element field_var_str[]
array allocated for that purpose.
Link: https://lkml.kernel.org/r/1c1a03798b02e67307412a0c719d1bfb69b13007.1601848695.git.zanussi@kernel.org
Fixes: 02205a6752 (tracing: Add support for 'field variables')
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
synth_field_size() returns either a positive size or an error (zero or
a negative value). However, the existing code assumes the only error
value is 0. It doesn't handle negative error codes, as it assigns
directly to field->size (a size_t; unsigned), thereby interpreting the
error code as a valid size instead.
Do the test before assignment to field->size.
[ axelrasmussen@google.com: changelog addition, first paragraph above ]
Link: https://lkml.kernel.org/r/9b6946d9776b2eeb43227678158196de1c3c6e1d.1601848695.git.zanussi@kernel.org
Fixes: 4b147936fa (tracing: Add support for 'synthetic' events)
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Tested-by: Axel Rasmussen <axelrasmussen@google.com>
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
32 is too small for this value, and anyway it makes more sense to use
MAX_FILTER_STR_VAL, as this is also the value used for variable-length
__strings.
Link: https://lkml.kernel.org/r/6adfd1668ac1fd8670bd58206944a762061a5559.1601848695.git.zanussi@kernel.org
Tested-by: Axel Rasmussen <axelrasmussen@google.com>
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
All remaining callers of bdget() outside of fs/block_dev.c want to get a
reference to the struct block_device for a given struct hd_struct. Add
a helper just for that and then mark bdget static.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add the support to route trace_marker buffer to other destination
via trace_export.
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Tingwei Zhang <tingwei@codeaurora.org>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Link: https://lore.kernel.org/r/20201005071319.78508-5-alexander.shishkin@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Only function traces can be exported to other destinations currently.
This patch exports event trace as well. Move trace export related
function to the beginning of file so other trace can call
trace_process_export() to export.
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Tingwei Zhang <tingwei@codeaurora.org>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Link: https://lore.kernel.org/r/20201005071319.78508-4-alexander.shishkin@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
More traces like event trace or trace marker will be supported.
Add flag for difference traces, so that they can be controlled
separately. Move current function trace to it's own flag
instead of global ftrace enable flag.
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Tingwei Zhang <tingwei@codeaurora.org>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Link: https://lore.kernel.org/r/20201005071319.78508-3-alexander.shishkin@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add bpf_this_cpu_ptr() to help access percpu var on this cpu. This
helper always returns a valid pointer, therefore no need to check
returned value for NULL. Also note that all programs run with
preemption disabled, which means that the returned pointer is stable
during all the execution of the program.
Signed-off-by: Hao Luo <haoluo@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200929235049.2533242-6-haoluo@google.com
Add bpf_per_cpu_ptr() to help bpf programs access percpu vars.
bpf_per_cpu_ptr() has the same semantic as per_cpu_ptr() in the kernel
except that it may return NULL. This happens when the cpu parameter is
out of range. So the caller must check the returned value.
Signed-off-by: Hao Luo <haoluo@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200929235049.2533242-5-haoluo@google.com
- Fix temp buffer accounting that caused a WARNING for
ftrace_dump_on_opps()
- Move the recursion check in one of the function callback helpers to the
beginning of the function, as if the rcu_is_watching() gets traced, it
will cause a recursive loop that will crash the kernel.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCX3UZ7hQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qlelAP4nzEIyE7s8HkKHo+IEvzEiYL523Xq7
zrTm27XnLjZ+EQD9ECbtea9me8kL+zBcG8H3Wu/ykN15LIT2ZsvVTrWYmwI=
=eTh4
-----END PGP SIGNATURE-----
Merge tag 'trace-v5.9-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
"Two tracing fixes:
- Fix temp buffer accounting that caused a WARNING for
ftrace_dump_on_opps()
- Move the recursion check in one of the function callback helpers to
the beginning of the function, as if the rcu_is_watching() gets
traced, it will cause a recursive loop that will crash the kernel"
* tag 'trace-v5.9-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
ftrace: Move RCU is watching check after recursion check
tracing: Fix trace_find_next_entry() accounting of temp buffer size
The first thing that the ftrace function callback helper functions should do
is to check for recursion. Peter Zijlstra found that when
"rcu_is_watching()" had its notrace removed, it caused perf function tracing
to crash. This is because the call of rcu_is_watching() is tested before
function recursion is checked and and if it is traced, it will cause an
infinite recursion loop.
rcu_is_watching() should still stay notrace, but to prevent this should
never had crashed in the first place. The recursion prevention must be the
first thing done in callback functions.
Link: https://lore.kernel.org/r/20200929112541.GM2628@hirez.programming.kicks-ass.net
Cc: stable@vger.kernel.org
Cc: Paul McKenney <paulmck@kernel.org>
Fixes: c68c0fa293 ("ftrace: Have ftrace_ops_get_func() handle RCU and PER_CPU flags too")
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reported-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The temp buffer size variable for trace_find_next_entry() was incorrectly
being updated when the size did not change. The temp buffer size should only
be updated when it is reallocated.
This is mostly an issue when used with ftrace_dump(). That's because
ftrace_dump() can not allocate a new buffer, and instead uses a temporary
buffer with a fix size. But the variable that keeps track of that size is
incorrectly updated with each call, and it could fall into the path that
would try to reallocate the buffer and produce a warning.
------------[ cut here ]------------
WARNING: CPU: 1 PID: 1601 at kernel/trace/trace.c:3548
trace_find_next_entry+0xd0/0xe0
Modules linked in [..]
CPU: 1 PID: 1601 Comm: bash Not tainted 5.9.0-rc5-test+ #521
Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v03.03
07/14/2016
RIP: 0010:trace_find_next_entry+0xd0/0xe0
Code: 40 21 00 00 4c 89 e1 31 d2 4c 89 ee 48 89 df e8 c6 9e ff ff 89 ab 54
21 00 00 5b 5d 41 5c 41 5d c3 48 63 d5 eb bf 31 c0 eb f0 <0f> 0b 48 63 d5 eb
b4 66 0f 1f 84 00 00 00 00 00 53 48 8d 8f 60 21
RSP: 0018:ffff95a4f2e8bd70 EFLAGS: 00010046
RAX: ffffffff96679fc0 RBX: ffffffff97910de0 RCX: ffffffff96679fc0
RDX: ffff95a4f2e8bd98 RSI: ffff95a4ee321098 RDI: ffffffff97913000
RBP: 0000000000000018 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000046 R12: ffff95a4f2e8bd98
R13: 0000000000000000 R14: ffff95a4ee321098 R15: 00000000009aa301
FS: 00007f8565484740(0000) GS:ffff95a55aa40000(0000)
knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055876bd43d90 CR3: 00000000b76e6003 CR4: 00000000001706e0
Call Trace:
trace_print_lat_context+0x58/0x2d0
? cpumask_next+0x16/0x20
print_trace_line+0x1a4/0x4f0
ftrace_dump.cold+0xad/0x12c
__handle_sysrq.cold+0x51/0x126
write_sysrq_trigger+0x3f/0x4a
proc_reg_write+0x53/0x80
vfs_write+0xca/0x210
ksys_write+0x70/0xf0
do_syscall_64+0x33/0x40
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7f8565579487
Code: 64 89 02 48 c7 c0 ff ff ff ff eb bb 0f 1f 80 00 00 00 00 f3 0f 1e fa
64 8b 04 25 18 00 00 00 85 c0 75 10 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff
77 51 c3 48 83 ec 28 48 89 54 24 18 48 89 74 24
RSP: 002b:00007ffd40707948 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f8565579487
RDX: 0000000000000002 RSI: 000055876bd74de0 RDI: 0000000000000001
RBP: 000055876bd74de0 R08: 000000000000000a R09: 0000000000000001
R10: 000055876bdec280 R11: 0000000000000246 R12: 0000000000000002
R13: 00007f856564a500 R14: 0000000000000002 R15: 00007f856564a700
irq event stamp: 109958
---[ end trace 7aab5b7e51484b00 ]---
Not only fix the updating of the temp buffer, but also do not free the temp
buffer before a new buffer is allocated (there's no reason to not continue
to use the current temp buffer if an allocation fails).
Cc: stable@vger.kernel.org
Fixes: 8e99cf91b9 ("tracing: Do not allocate buffer in trace_find_next_entry() in atomic")
Reported-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
A helper is added to allow seq file writing of kernel data
structures using vmlinux BTF. Its signature is
long bpf_seq_printf_btf(struct seq_file *m, struct btf_ptr *ptr,
u32 btf_ptr_size, u64 flags);
Flags and struct btf_ptr definitions/use are identical to the
bpf_snprintf_btf helper, and the helper returns 0 on success
or a negative error value.
Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/1601292670-1616-8-git-send-email-alan.maguire@oracle.com
A helper is added to support tracing kernel type information in BPF
using the BPF Type Format (BTF). Its signature is
long bpf_snprintf_btf(char *str, u32 str_size, struct btf_ptr *ptr,
u32 btf_ptr_size, u64 flags);
struct btf_ptr * specifies
- a pointer to the data to be traced
- the BTF id of the type of data pointed to
- a flags field is provided for future use; these flags
are not to be confused with the BTF_F_* flags
below that control how the btf_ptr is displayed; the
flags member of the struct btf_ptr may be used to
disambiguate types in kernel versus module BTF, etc;
the main distinction is the flags relate to the type
and information needed in identifying it; not how it
is displayed.
For example a BPF program with a struct sk_buff *skb
could do the following:
static struct btf_ptr b = { };
b.ptr = skb;
b.type_id = __builtin_btf_type_id(struct sk_buff, 1);
bpf_snprintf_btf(str, sizeof(str), &b, sizeof(b), 0, 0);
Default output looks like this:
(struct sk_buff){
.transport_header = (__u16)65535,
.mac_header = (__u16)65535,
.end = (sk_buff_data_t)192,
.head = (unsigned char *)0x000000007524fd8b,
.data = (unsigned char *)0x000000007524fd8b,
.truesize = (unsigned int)768,
.users = (refcount_t){
.refs = (atomic_t){
.counter = (int)1,
},
},
}
Flags modifying display are as follows:
- BTF_F_COMPACT: no formatting around type information
- BTF_F_NONAME: no struct/union member names/types
- BTF_F_PTR_RAW: show raw (unobfuscated) pointer values;
equivalent to %px.
- BTF_F_ZERO: show zero-valued struct/union members;
they are not displayed by default
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/1601292670-1616-4-git-send-email-alan.maguire@oracle.com
Add .test_run for raw_tracepoint. Also, introduce a new feature that runs
the target program on a specific CPU. This is achieved by a new flag in
bpf_attr.test, BPF_F_TEST_RUN_ON_CPU. When this flag is set, the program
is triggered on cpu with id bpf_attr.test.cpu. This feature is needed for
BPF programs that handle perf_event and other percpu resources, as the
program can access these resource locally.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200925205432.1777-2-songliubraving@fb.com
Initialize per-instance event list in early boot time (before
initializing instance directory on tracefs). This fixes boot-time
tracing to correctly handle the boot-time per-instance settings.
Link: https://lkml.kernel.org/r/160096560826.182763.17110991546046128881.stgit@devnote2
Fixes: 4114fbfd02 ("tracing: Enable creating new instance early boot")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add a littler helper to make the somewhat arcane bd_contains checks a
little more obvious.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
It is advised to use module_name() macro instead of dereferencing mod->name
directly. This makes sense for consistencys sake and also it prevents a
hard dependency to CONFIG_MODULES.
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Link: https://lkml.kernel.org/r/20200818050857.117998-1-jarkko.sakkinen@linux.intel.com
Alexei Starovoitov says:
====================
pull-request: bpf-next 2020-09-23
The following pull-request contains BPF updates for your *net-next* tree.
We've added 95 non-merge commits during the last 22 day(s) which contain
a total of 124 files changed, 4211 insertions(+), 2040 deletions(-).
The main changes are:
1) Full multi function support in libbpf, from Andrii.
2) Refactoring of function argument checks, from Lorenz.
3) Make bpf_tail_call compatible with functions (subprograms), from Maciej.
4) Program metadata support, from YiFei.
5) bpf iterator optimizations, from Yonghong.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Two minor conflicts:
1) net/ipv4/route.c, adding a new local variable while
moving another local variable and removing it's
initial assignment.
2) drivers/net/dsa/microchip/ksz9477.c, overlapping changes.
One pretty prints the port mode differently, whilst another
changes the driver to try and obtain the port mode from
the port node rather than the switch node.
Signed-off-by: David S. Miller <davem@davemloft.net>
- Check kprobe is enabled before unregistering from ftrace as it isn't
registered when disabled.
- Remove kprobes enabled via command-line that is on init text when freed.
- Add missing RCU synchronization for ftrace trampoline symbols removed
from kallsyms.
- Free trampoline on error path if ftrace_startup() fails.
- Give more space for the longer PID numbers in trace output.
- Fix a possible double free in the histogram code.
- A couple of fixes that were discovered by sparse.
-----BEGIN PGP SIGNATURE-----
iIkEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCX2lEchQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qokAAQDphHFTOlgjKi7lF7bc5V1bl/MT1bVo
bJRHV8w2agtXMgD49ElFOl6znXqid3X++0dYZ5/AQgOZXf1rsYS05Pj0Dw==
=+cVX
-----END PGP SIGNATURE-----
Merge tag 'trace-v5.9-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
- Check kprobe is enabled before unregistering from ftrace as it isn't
registered when disabled.
- Remove kprobes enabled via command-line that is on init text when
freed.
- Add missing RCU synchronization for ftrace trampoline symbols removed
from kallsyms.
- Free trampoline on error path if ftrace_startup() fails.
- Give more space for the longer PID numbers in trace output.
- Fix a possible double free in the histogram code.
- A couple of fixes that were discovered by sparse.
* tag 'trace-v5.9-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
bootconfig: init: make xbc_namebuf static
kprobes: tracing/kprobes: Fix to kill kprobes on initmem after boot
tracing: fix double free
ftrace: Let ftrace_enable_sysctl take a kernel pointer buffer
tracing: Make the space reserved for the pid wider
ftrace: Fix missing synchronize_rcu() removing trampoline from kallsyms
ftrace: Free the trampoline when ftrace_startup() fails
kprobes: Fix to check probe enabled before disarm_kprobe_ftrace()
Initialize boot-time tracing in core_initcall_sync instead of
fs_initcall, and initialize required tracers (kprobes and synth)
in core_initcall. This will allow the boot-time tracing to trace
__init code from the beginning of postcore_initcall stage.
Link: https://lkml.kernel.org/r/159974155727.478751.7486926132902849578.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Enable creating new trace_array instance in early boot stage.
If the instances directory is not created, postpone it until
the tracefs is initialized.
Link: https://lkml.kernel.org/r/159974154763.478751.6289753509587233103.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Split the event fields initialization from creating new event directory.
This allows the boot-time tracing to define dynamic events before
initializing events directory on tracefs.
Link: https://lkml.kernel.org/r/159974153790.478751.3475515065034825374.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Define event fields at early stage so that boot-time tracing can
access the event fields (like per-event filter setting).
Link: https://lkml.kernel.org/r/159974152862.478751.2023768466808361350.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Support perf-style return probe ("SYMBOL%return") for kprobe events.
This will allow boot-time tracing user to define a return probe event.
Link: https://lkml.kernel.org/r/159972813535.428528.4437029657208468954.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add per-instance tracing_on option, which will be useful with
traceon/traceoff event trigger actions. For example, if we
disable tracing_on by default and set traceon and traceoff on
a pair of events, we can trace functions between the pair of
events.
Link: https://lkml.kernel.org/r/159972811538.428528.2561315102284268611.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
It seems that alloc_retstack_tasklist() can also take a lockless
approach for scanning the tasklist, instead of using the big global
tasklist_lock. For this we also kill another deprecated and rcu-unsafe
tsk->thread_group user replacing it with for_each_process_thread(),
maintaining semantics.
Here tasklist_lock does not protect anything other than the list
against concurrent fork/exit. And considering that the whole thing
is capped by FTRACE_RETSTACK_ALLOC_SIZE (32), it should not be a
problem to have a pontentially stale, yet stable, list. The task cannot
go away either, so we don't risk racing with ftrace_graph_exit_task()
which clears the retstack.
The tsk->ret_stack management is not protected by tasklist_lock, being
serialized with the corresponding publish/subscribe barriers against
concurrent ftrace_push_return_trace(). In addition this plays nicer
with cachelines by avoiding two atomic ops in the uncontended case.
Link: https://lkml.kernel.org/r/20200907013326.9870-1-dave@stgolabs.net
Acked-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The "tr" is a stack variable so setting it to NULL before a return is
a no-op. Delete the assignment.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
It is advised to use module_name() macro instead of dereferencing mod->name
directly. This makes sense for consistencys sake and also it prevents a
hard dependency to CONFIG_MODULES.
Link: https://lkml.kernel.org/r/20200818050857.117998-1-jarkko.sakkinen@linux.intel.com
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: linux-mm@kvack.org
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Jessica Yu <jeyu@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>,
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Will Deacon <will@kernel.org>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Some kernels builds might inline vfs_getattr call within fstat
syscall code path, so fentry/vfs_getattr trampoline is not called.
Add security_inode_getattr to allowlist and switch the d_path test stat
trampoline to security_inode_getattr.
Keeping dentry_open and filp_close, because they are in their own
files, so unlikely to be inlined, but in case they are, adding
security_file_open.
Adding flags that indicate trampolines were called and failing
the test if any of them got missed, so it's easier to identify
the issue next time.
Fixes: e4d1af4b16 ("selftests/bpf: Add test for d_path helper")
Suggested-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200918112338.2618444-1-jolsa@kernel.org
Function prototypes using ARG_PTR_TO_BTF_ID currently use two ways to signal
which BTF IDs are acceptable. First, bpf_func_proto.btf_id is an array of
IDs, one for each argument. This array is only accessed up to the highest
numbered argument that uses ARG_PTR_TO_BTF_ID and may therefore be less than
five arguments long. It usually points at a BTF_ID_LIST. Second, check_btf_id
is a function pointer that is called by the verifier if present. It gets the
actual BTF ID of the register, and the argument number we're currently checking.
It turns out that the only user check_arg_btf_id ignores the argument, and is
simply used to check whether the BTF ID has a struct sock_common at it's start.
Replace both of these mechanisms with an explicit BTF ID for each argument
in a function proto. Thanks to btf_struct_ids_match this is very flexible:
check_arg_btf_id can be replaced by requiring struct sock_common.
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200921121227.255763-5-lmb@cloudflare.com
Merge fixes from Andrew Morton:
"15 patches.
Subsystems affected by this patch series: mailmap, mm/hotfixes,
mm/thp, mm/memory-hotplug, misc, kcsan"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
kcsan: kconfig: move to menu 'Generic Kernel Debugging Instruments'
fs/fs-writeback.c: adjust dirtytime_interval_handler definition to match prototype
stackleak: let stack_erasing_sysctl take a kernel pointer buffer
ftrace: let ftrace_enable_sysctl take a kernel pointer buffer
mm/memory_hotplug: drain per-cpu pages again during memory offline
selftests/vm: fix display of page size in map_hugetlb
mm/thp: fix __split_huge_pmd_locked() for migration PMD
kprobes: fix kill kprobe which has been marked as gone
tmpfs: restore functionality of nr_inodes=0
mlock: fix unevictable_pgs event counts on THP
mm: fix check_move_unevictable_pages() on THP
mm: migration of hugetlbfs page skip memcg
ksm: reinstate memcg charge on copied pages
mailmap: add older email addresses for Kees Cook
Commit 32927393dc ("sysctl: pass kernel pointers to ->proc_handler")
changed ctl_table.proc_handler to take a kernel pointer. Adjust the
signature of ftrace_enable_sysctl to match ctl_table.proc_handler which
fixes the following sparse warning:
kernel/trace/ftrace.c:7544:43: warning: incorrect type in argument 3 (different address spaces)
kernel/trace/ftrace.c:7544:43: expected void *
kernel/trace/ftrace.c:7544:43: got void [noderef] __user *buffer
Fixes: 32927393dc ("sysctl: pass kernel pointers to ->proc_handler")
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Link: https://lkml.kernel.org/r/20200907093207.13540-1-tklauser@distanz.ch
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Current tracing_init_dentry() return a d_entry pointer, while is not
necessary. This function returns NULL on success or error on failure,
which means there is no valid d_entry pointer return.
Let's return 0 on success and negative value for error.
Link: https://lkml.kernel.org/r/20200712011036.70948-5-richard.weiyang@linux.alibaba.com
Signed-off-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Currently we have following call flow:
tracer_init_tracefs()
tracing_init_dentry()
event_trace_init()
tracing_init_dentry()
This shows tracing_init_dentry() is called twice in this flow and this
is not necessary.
Let's remove the second one when it is for sure be properly initialized.
Link: https://lkml.kernel.org/r/20200712011036.70948-4-richard.weiyang@linux.alibaba.com
Signed-off-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
clang static analyzer reports this problem
trace_events_hist.c:3824:3: warning: Attempt to free
released memory
kfree(hist_data->attrs->var_defs.name[i]);
In parse_var_defs() if there is a problem allocating
var_defs.expr, the earlier var_defs.name is freed.
This free is duplicated by free_var_defs() which frees
the rest of the list.
Because free_var_defs() has to run anyway, remove the
second free fom parse_var_defs().
Link: https://lkml.kernel.org/r/20200907135845.15804-1-trix@redhat.com
Cc: stable@vger.kernel.org
Fixes: 30350d65ac ("tracing: Add variable support to hist triggers")
Reviewed-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
