Branch data available to BPF programs can be very useful to get stack traces
out of userspace application.
Commit fff7b64355 ("bpf: Add bpf_read_branch_records() helper") added BPF
support to capture branch records in x86. Enable this feature also for other
architectures as well by removing checks specific to x86.
If an architecture doesn't support branch records, bpf_read_branch_records()
still has appropriate checks and it will return an -EINVAL in that scenario.
Based on UAPI helper doc in include/uapi/linux/bpf.h, unsupported architectures
should return -ENOENT in such case. Hence, update the appropriate check to
return -ENOENT instead.
Selftest 'perf_branches' result on power9 machine which has the branch stacks
support:
- Before this patch:
[command]# ./test_progs -t perf_branches
#88/1 perf_branches/perf_branches_hw:FAIL
#88/2 perf_branches/perf_branches_no_hw:OK
#88 perf_branches:FAIL
Summary: 0/1 PASSED, 0 SKIPPED, 1 FAILED
- After this patch:
[command]# ./test_progs -t perf_branches
#88/1 perf_branches/perf_branches_hw:OK
#88/2 perf_branches/perf_branches_no_hw:OK
#88 perf_branches:OK
Summary: 1/2 PASSED, 0 SKIPPED, 0 FAILED
Selftest 'perf_branches' result on power9 machine which doesn't have branch
stack report:
- After this patch:
[command]# ./test_progs -t perf_branches
#88/1 perf_branches/perf_branches_hw:SKIP
#88/2 perf_branches/perf_branches_no_hw:OK
#88 perf_branches:OK
Summary: 1/1 PASSED, 1 SKIPPED, 0 FAILED
Fixes: fff7b64355 ("bpf: Add bpf_read_branch_records() helper")
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20211206073315.77432-1-kjain@linux.ibm.com
When comparing two strings for the "onmatch" histogram trigger, fields
that are strings use string comparisons, which do not care about being
signed or not.
Do not fail to match two string fields if one is unsigned char array and
the other is a signed char array.
Link: https://lore.kernel.org/all/20211129123043.5cfd687a@gandalf.local.home/
Cc: stable@vgerk.kernel.org
Cc: Tom Zanussi <zanussi@kernel.org>
Cc: Yafang Shao <laoar.shao@gmail.com>
Fixes: b05e89ae7c ("tracing: Accept different type for synthetic event fields")
Reviewed-by: Masami Hiramatsu <mhiramatsu@kernel.org>
Reported-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Just use the disk attached to the request_queue instead.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20211126121802.2090656-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
When creating a new event (via a module, kprobe, eprobe, etc), the
descriptors that are created must add flags for pid filtering if an
instance has pid filtering enabled, as the flags are used at the time the
event is executed to know if pid filtering should be done or not.
The "Only trace this pid" case was added, but a cut and paste error made
that case checked twice, instead of checking the "Trace all but this pid"
case.
Link: https://lore.kernel.org/all/202111280401.qC0z99JB-lkp@intel.com/
Fixes: 6cb206508b ("tracing: Check pid filtering when creating events")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
If a event is filtered by pid and a trigger that requires processing of
the event to happen is a attached to the event, the discard portion does
not take the pid filtering into account, and the event will then be
recorded when it should not have been.
Cc: stable@vger.kernel.org
Fixes: 3fdaf80f4a ("tracing: Implement event pid filtering")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
When pid filtering is activated in an instance, all of the events trace
files for that instance has the PID_FILTER flag set. This determines
whether or not pid filtering needs to be done on the event, otherwise the
event is executed as normal.
If pid filtering is enabled when an event is created (via a dynamic event
or modules), its flag is not updated to reflect the current state, and the
events are not filtered properly.
Cc: stable@vger.kernel.org
Fixes: 3fdaf80f4a ("tracing: Implement event pid filtering")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add missing 'tu' variable initialization in the probes loop,
otherwise the head 'tu' is used instead of added probes.
Link: https://lkml.kernel.org/r/20211123142801.182530-1-jolsa@kernel.org
Cc: stable@vger.kernel.org
Fixes: 99c9a923e9 ("tracing/uprobe: Fix double perf_event linking on multiprobe uprobe")
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
- Fix double free in destroy_hist_field
- Harden memset() of trace_iterator structure
- Do not warn in trace printk check when test buffer fills up
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Merge tag 'trace-v5.16-6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
- Fix double free in destroy_hist_field
- Harden memset() of trace_iterator structure
- Do not warn in trace printk check when test buffer fills up
* tag 'trace-v5.16-6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Don't use out-of-sync va_list in event printing
tracing: Use memset_startat() to zero struct trace_iterator
tracing/histogram: Fix UAF in destroy_hist_field()
If trace_seq becomes full, trace_seq_vprintf() no longer consumes
arguments from va_list, making va_list out of sync with format
processing by trace_check_vprintf().
This causes va_arg() in trace_check_vprintf() to return wrong
positional argument, which results into a WARN_ON_ONCE() hit.
ftrace_stress_test from LTP triggers this situation.
Fix it by explicitly avoiding further use if va_list at the point
when it's consistency can no longer be guaranteed.
Link: https://lkml.kernel.org/r/20211118145516.13219-1-nikita.yushchenko@virtuozzo.com
Signed-off-by: Nikita Yushchenko <nikita.yushchenko@virtuozzo.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
In preparation for FORTIFY_SOURCE performing compile-time and run-time
field bounds checking for memset(), avoid intentionally writing across
neighboring fields.
Use memset_startat() to avoid confusing memset() about writing beyond
the target struct member.
Link: https://lkml.kernel.org/r/20211118202217.1285588-1-keescook@chromium.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Current release - regressions:
- devlink: don't throw an error if flash notification sent before
devlink visible
- page_pool: Revert "page_pool: disable dma mapping support...",
turns out there are active arches who need it
Current release - new code bugs:
- amt: cancel delayed_work synchronously in amt_fini()
Previous releases - regressions:
- xsk: fix crash on double free in buffer pool
- bpf: fix inner map state pruning regression causing program
rejections
- mac80211: drop check for DONT_REORDER in __ieee80211_select_queue,
preventing mis-selecting the best effort queue
- mac80211: do not access the IV when it was stripped
- mac80211: fix radiotap header generation, off-by-one
- nl80211: fix getting radio statistics in survey dump
- e100: fix device suspend/resume
Previous releases - always broken:
- tcp: fix uninitialized access in skb frags array for Rx 0cp
- bpf: fix toctou on read-only map's constant scalar tracking
- bpf: forbid bpf_ktime_get_coarse_ns and bpf_timer_* in tracing progs
- tipc: only accept encrypted MSG_CRYPTO msgs
- smc: transfer remaining wait queue entries during fallback,
fix missing wake ups
- udp: validate checksum in udp_read_sock() (when sockmap is used)
- sched: act_mirred: drop dst for the direction from egress to ingress
- virtio_net_hdr_to_skb: count transport header in UFO, prevent
allowing bad skbs into the stack
- nfc: reorder the logic in nfc_{un,}register_device, fix unregister
- ipsec: check return value of ipv6_skip_exthdr
- usb: r8152: add MAC passthrough support for more Lenovo Docks
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'net-5.16-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Jakub Kicinski:
"Including fixes from bpf, mac80211.
Current release - regressions:
- devlink: don't throw an error if flash notification sent before
devlink visible
- page_pool: Revert "page_pool: disable dma mapping support...",
turns out there are active arches who need it
Current release - new code bugs:
- amt: cancel delayed_work synchronously in amt_fini()
Previous releases - regressions:
- xsk: fix crash on double free in buffer pool
- bpf: fix inner map state pruning regression causing program
rejections
- mac80211: drop check for DONT_REORDER in __ieee80211_select_queue,
preventing mis-selecting the best effort queue
- mac80211: do not access the IV when it was stripped
- mac80211: fix radiotap header generation, off-by-one
- nl80211: fix getting radio statistics in survey dump
- e100: fix device suspend/resume
Previous releases - always broken:
- tcp: fix uninitialized access in skb frags array for Rx 0cp
- bpf: fix toctou on read-only map's constant scalar tracking
- bpf: forbid bpf_ktime_get_coarse_ns and bpf_timer_* in tracing
progs
- tipc: only accept encrypted MSG_CRYPTO msgs
- smc: transfer remaining wait queue entries during fallback, fix
missing wake ups
- udp: validate checksum in udp_read_sock() (when sockmap is used)
- sched: act_mirred: drop dst for the direction from egress to
ingress
- virtio_net_hdr_to_skb: count transport header in UFO, prevent
allowing bad skbs into the stack
- nfc: reorder the logic in nfc_{un,}register_device, fix unregister
- ipsec: check return value of ipv6_skip_exthdr
- usb: r8152: add MAC passthrough support for more Lenovo Docks"
* tag 'net-5.16-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (96 commits)
ptp: ocp: Fix a couple NULL vs IS_ERR() checks
net: ethernet: dec: tulip: de4x5: fix possible array overflows in type3_infoblock()
net: tulip: de4x5: fix the problem that the array 'lp->phy[8]' may be out of bound
ipv6: check return value of ipv6_skip_exthdr
e100: fix device suspend/resume
devlink: Don't throw an error if flash notification sent before devlink visible
page_pool: Revert "page_pool: disable dma mapping support..."
ethernet: hisilicon: hns: hns_dsaf_misc: fix a possible array overflow in hns_dsaf_ge_srst_by_port()
octeontx2-af: debugfs: don't corrupt user memory
NFC: add NCI_UNREG flag to eliminate the race
NFC: reorder the logic in nfc_{un,}register_device
NFC: reorganize the functions in nci_request
tipc: check for null after calling kmemdup
i40e: Fix display error code in dmesg
i40e: Fix creation of first queue by omitting it if is not power of two
i40e: Fix warning message and call stack during rmmod i40e driver
i40e: Fix ping is lost after configuring ADq on VF
i40e: Fix changing previously set num_queue_pairs for PFs
i40e: Fix NULL ptr dereference on VSI filter sync
i40e: Fix correct max_pkt_size on VF RX queue
...
Calling destroy_hist_field() on an expression will recursively free
any operands associated with the expression. If during expression
parsing the operands of the expression are already set when an error
is encountered, there is no need to explicity free the operands. Doing
so will result in destroy_hist_field() being called twice for the
operands and lead to a use-after-free (UAF) error.
If the operands are associated with the expression, only call
destroy_hist_field() on the expression since the operands will be
recursively freed.
Link: https://lore.kernel.org/all/CAHk-=wgcrEbFgkw9720H3tW-AhHOoEKhYwZinYJw4FpzSaJ6_Q@mail.gmail.com/
Link: https://lkml.kernel.org/r/20211118011542.1420131-1-kaleshsingh@google.com
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
Fixes: 8b5d46fd7a ("tracing/histogram: Optimize division by constants")
Reported-by: kernel test robot <oliver.sang@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Daniel Borkmann says:
====================
pull-request: bpf-next 2021-11-15
We've added 72 non-merge commits during the last 13 day(s) which contain
a total of 171 files changed, 2728 insertions(+), 1143 deletions(-).
The main changes are:
1) Add btf_type_tag attributes to bring kernel annotations like __user/__rcu to
BTF such that BPF verifier will be able to detect misuse, from Yonghong Song.
2) Big batch of libbpf improvements including various fixes, future proofing APIs,
and adding a unified, OPTS-based bpf_prog_load() low-level API, from Andrii Nakryiko.
3) Add ingress_ifindex to BPF_SK_LOOKUP program type for selectively applying the
programmable socket lookup logic to packets from a given netdev, from Mark Pashmfouroush.
4) Remove the 128M upper JIT limit for BPF programs on arm64 and add selftest to
ensure exception handling still works, from Russell King and Alan Maguire.
5) Add a new bpf_find_vma() helper for tracing to map an address to the backing
file such as shared library, from Song Liu.
6) Batch of various misc fixes to bpftool, fixing a memory leak in BPF program dump,
updating documentation and bash-completion among others, from Quentin Monnet.
7) Deprecate libbpf bpf_program__get_prog_info_linear() API and migrate its users as
the API is heavily tailored around perf and is non-generic, from Dave Marchevsky.
8) Enable libbpf's strict mode by default in bpftool and add a --legacy option as an
opt-out for more relaxed BPF program requirements, from Stanislav Fomichev.
9) Fix bpftool to use libbpf_get_error() to check for errors, from Hengqi Chen.
* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (72 commits)
bpftool: Use libbpf_get_error() to check error
bpftool: Fix mixed indentation in documentation
bpftool: Update the lists of names for maps and prog-attach types
bpftool: Fix indent in option lists in the documentation
bpftool: Remove inclusion of utilities.mak from Makefiles
bpftool: Fix memory leak in prog_dump()
selftests/bpf: Fix a tautological-constant-out-of-range-compare compiler warning
selftests/bpf: Fix an unused-but-set-variable compiler warning
bpf: Introduce btf_tracing_ids
bpf: Extend BTF_ID_LIST_GLOBAL with parameter for number of IDs
bpftool: Enable libbpf's strict mode by default
docs/bpf: Update documentation for BTF_KIND_TYPE_TAG support
selftests/bpf: Clarify llvm dependency with btf_tag selftest
selftests/bpf: Add a C test for btf_type_tag
selftests/bpf: Rename progs/tag.c to progs/btf_decl_tag.c
selftests/bpf: Test BTF_KIND_DECL_TAG for deduplication
selftests/bpf: Add BTF_KIND_TYPE_TAG unit tests
selftests/bpf: Test libbpf API function btf__add_type_tag()
bpftool: Support BTF_KIND_TYPE_TAG
libbpf: Support BTF_KIND_TYPE_TAG
...
====================
Link: https://lore.kernel.org/r/20211115162008.25916-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
A fix to only copy the size of the field to the histogram string
did not take into account that the size can be larger than the
storage.
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Merge tag 'trace-v5.16-5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fix from Steven Rostedt:
"Update to tracing histogram variable string copy
A fix to only copy the size of the field to the histogram string did
not take into account that the size can be larger than the storage"
* tag 'trace-v5.16-5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Add length protection to histogram string copies
The string copies to the histogram storage has a max size of 256 bytes
(defined by MAX_FILTER_STR_VAL). Only the string size of the event field
needs to be copied to the event storage, but no more than what is in the
event storage. Although nothing should be bigger than 256 bytes, there's
no protection against overwriting of the storage if one day there is.
Copy no more than the destination size, and enforce it.
Also had to turn MAX_FILTER_STR_VAL into an unsigned int, to keep the
min() comparison of the string sizes of comparable types.
Link: https://lore.kernel.org/all/CAHk-=wjREUihCGrtRBwfX47y_KrLCGjiq3t6QtoNJpmVrAEb1w@mail.gmail.com/
Link: https://lkml.kernel.org/r/20211114132834.183429a4@rorschach.local.home
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Tom Zanussi <zanussi@kernel.org>
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Fixes: 63f84ae6b8 ("tracing/histogram: Do not copy the fixed-size char array field over the field size")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
- Make local osnoise_instances static
- Copy just actual size of histogram strings
- Properly check missing operands in histogram expressions
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Merge tag 'trace-v5.16-4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
"Three tracing fixes:
- Make local osnoise_instances static
- Copy just actual size of histogram strings
- Properly check missing operands in histogram expressions"
* tag 'trace-v5.16-4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing/histogram: Fix check for missing operands in an expression
tracing/histogram: Do not copy the fixed-size char array field over the field size
tracing/osnoise: Make osnoise_instances static
If a binary operation is detected while parsing an expression string,
the operand strings are deduced by splitting the experssion string at
the position of the detected binary operator. Both operand strings are
sub-strings (can be empty string) of the expression string but will
never be NULL.
Currently a NULL check is used for missing operands, fix this by
checking for empty strings instead.
Link: https://lkml.kernel.org/r/20211112191324.1302505-1-kaleshsingh@google.com
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
Fixes: 9710b2f341 ("tracing: Fix operator precedence for hist triggers expression")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Do not copy the fixed-size char array field of the events over
the field size. The histogram treats char array as a string and
there are 2 types of char array in the event, fixed-size and
dynamic string. The dynamic string (__data_loc) field must be
null terminated, but the fixed-size char array field may not
be null terminated (not a string, but just a data).
In that case, histogram can copy the data after the field.
This uses the original field size for fixed-size char array
field to restrict the histogram not to access over the original
field size.
Link: https://lkml.kernel.org/r/163673292822.195747.3696966210526410250.stgit@devnote2
Fixes: 02205a6752 (tracing: Add support for 'field variables')
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Similar to btf_sock_ids, btf_tracing_ids provides btf ID for task_struct,
file, and vm_area_struct via easy to understand format like
btf_tracing_ids[BTF_TRACING_TYPE_[TASK|file|VMA]].
Suggested-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20211112150243.1270987-3-songliubraving@fb.com
We can't call unregister_ftrace_function under ftrace_lock.
Link: https://lkml.kernel.org/r/20211109114217.1645296-1-jolsa@kernel.org
Fixes: ed29271894 ("ftrace/direct: Do not disable when switching direct callers")
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The resetting of the entire ring buffer use to simply go through and reset
each individual CPU buffer that had its own protection and synchronization.
But this was very slow, due to performing a synchronization for each CPU.
The code was reshuffled to do one disabling of all CPU buffers, followed
by a single RCU synchronization, and then the resetting of each of the CPU
buffers. But unfortunately, the mutex that prevented multiple occurrences
of resetting the buffer was not moved to the upper function, and there is
nothing to protect from it.
Take the ring buffer mutex around the global reset.
Cc: stable@vger.kernel.org
Fixes: b23d7a5f4a ("ring-buffer: speed up buffer resets by avoiding synchronize_rcu for each CPU")
Reported-by: "Tzvetomir Stoyanov (VMware)" <tz.stoyanov@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Merge more updates from Andrew Morton:
"87 patches.
Subsystems affected by this patch series: mm (pagecache and hugetlb),
procfs, misc, MAINTAINERS, lib, checkpatch, binfmt, kallsyms, ramfs,
init, codafs, nilfs2, hfs, crash_dump, signals, seq_file, fork,
sysvfs, kcov, gdb, resource, selftests, and ipc"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (87 commits)
ipc/ipc_sysctl.c: remove fallback for !CONFIG_PROC_SYSCTL
ipc: check checkpoint_restore_ns_capable() to modify C/R proc files
selftests/kselftest/runner/run_one(): allow running non-executable files
virtio-mem: disallow mapping virtio-mem memory via /dev/mem
kernel/resource: disallow access to exclusive system RAM regions
kernel/resource: clean up and optimize iomem_is_exclusive()
scripts/gdb: handle split debug for vmlinux
kcov: replace local_irq_save() with a local_lock_t
kcov: avoid enable+disable interrupts if !in_task()
kcov: allocate per-CPU memory on the relevant node
Documentation/kcov: define `ip' in the example
Documentation/kcov: include types.h in the example
sysv: use BUILD_BUG_ON instead of runtime check
kernel/fork.c: unshare(): use swap() to make code cleaner
seq_file: fix passing wrong private data
seq_file: move seq_escape() to a header
signal: remove duplicate include in signal.h
crash_dump: remove duplicate include in crash_dump.h
crash_dump: fix boolreturn.cocci warning
hfs/hfsplus: use WARN_ON for sanity check
...
Move core_kernel_data() into sections.h and rename it to
is_kernel_core_data(), also make it return bool value, then update all the
callers.
Link: https://lkml.kernel.org/r/20210930071143.63410-4-wangkefeng.wang@huawei.com
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Alexander Potapenko <glider@google.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Christophe Leroy <christophe.leroy@csgroup.eu>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In some profiler use cases, it is necessary to map an address to the
backing file, e.g., a shared library. bpf_find_vma helper provides a
flexible way to achieve this. bpf_find_vma maps an address of a task to
the vma (vm_area_struct) for this address, and feed the vma to an callback
BPF function. The callback function is necessary here, as we need to
ensure mmap_sem is unlocked.
It is necessary to lock mmap_sem for find_vma. To lock and unlock mmap_sem
safely when irqs are disable, we use the same mechanism as stackmap with
build_id. Specifically, when irqs are disabled, the unlocked is postponed
in an irq_work. Refactor stackmap.c so that the irq_work is shared among
bpf_find_vma and stackmap helpers.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Hengqi Chen <hengqi.chen@gmail.com>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20211105232330.1936330-2-songliubraving@fb.com
- osnoise and timerlat updates that will work with the RTLA tool (Real-Time
Linux Analysis). Specifically it disconnects the work load (threads
that look for latency) from the tracing instances attached to them,
allowing for more than one instance to retrieve data from the work load.
- Optimization on division in the trace histogram trigger code to use shift
and multiply when possible. Also added documentation.
- Fix prototype to my_direct_func in direct ftrace trampoline sample code.
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Merge tag 'trace-v5.16-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull more tracing updates from Steven Rostedt:
- osnoise and timerlat updates that will work with the RTLA tool
(Real-Time Linux Analysis).
Specifically it disconnects the work load (threads that look for
latency) from the tracing instances attached to them, allowing for
more than one instance to retrieve data from the work load.
- Optimization on division in the trace histogram trigger code to use
shift and multiply when possible. Also added documentation.
- Fix prototype to my_direct_func in direct ftrace trampoline sample
code.
* tag 'trace-v5.16-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
ftrace/samples: Add missing prototype for my_direct_func
tracing/selftests: Add tests for hist trigger expression parsing
tracing/histogram: Document hist trigger variables
tracing/histogram: Update division by 0 documentation
tracing/histogram: Optimize division by constants
tracing/osnoise: Remove PREEMPT_RT ifdefs from inside functions
tracing/osnoise: Remove STACKTRACE ifdefs from inside functions
tracing/osnoise: Allow multiple instances of the same tracer
tracing/osnoise: Remove TIMERLAT ifdefs from inside functions
tracing/osnoise: Support a list of trace_array *tr
tracing/osnoise: Use start/stop_per_cpu_kthreads() on osnoise_cpus_write()
tracing/osnoise: Split workload start from the tracer start
tracing/osnoise: Improve comments about barrier need for NMI callbacks
tracing/osnoise: Do not follow tracing_cpumask
- Remove socket skb caches
- Add a SO_RESERVE_MEM socket op to forward allocate buffer space
and avoid memory accounting overhead on each message sent
- Introduce managed neighbor entries - added by control plane and
resolved by the kernel for use in acceleration paths (BPF / XDP
right now, HW offload users will benefit as well)
- Make neighbor eviction on link down controllable by userspace
to work around WiFi networks with bad roaming implementations
- vrf: Rework interaction with netfilter/conntrack
- fq_codel: implement L4S style ce_threshold_ect1 marking
- sch: Eliminate unnecessary RCU waits in mini_qdisc_pair_swap()
BPF:
- Add support for new btf kind BTF_KIND_TAG, arbitrary type tagging
as implemented in LLVM14
- Introduce bpf_get_branch_snapshot() to capture Last Branch Records
- Implement variadic trace_printk helper
- Add a new Bloomfilter map type
- Track <8-byte scalar spill and refill
- Access hw timestamp through BPF's __sk_buff
- Disallow unprivileged BPF by default
- Document BPF licensing
Netfilter:
- Introduce egress hook for looking at raw outgoing packets
- Allow matching on and modifying inner headers / payload data
- Add NFT_META_IFTYPE to match on the interface type either from
ingress or egress
Protocols:
- Multi-Path TCP:
- increase default max additional subflows to 2
- rework forward memory allocation
- add getsockopts: MPTCP_INFO, MPTCP_TCPINFO, MPTCP_SUBFLOW_ADDRS
- MCTP flow support allowing lower layer drivers to configure msg
muxing as needed
- Automatic Multicast Tunneling (AMT) driver based on RFC7450
- HSR support the redbox supervision frames (IEC-62439-3:2018)
- Support for the ip6ip6 encapsulation of IOAM
- Netlink interface for CAN-FD's Transmitter Delay Compensation
- Support SMC-Rv2 eliminating the current same-subnet restriction,
by exploiting the UDP encapsulation feature of RoCE adapters
- TLS: add SM4 GCM/CCM crypto support
- Bluetooth: initial support for link quality and audio/codec
offload
Driver APIs:
- Add a batched interface for RX buffer allocation in AF_XDP
buffer pool
- ethtool: Add ability to control transceiver modules' power mode
- phy: Introduce supported interfaces bitmap to express MAC
capabilities and simplify PHY code
- Drop rtnl_lock from DSA .port_fdb_{add,del} callbacks
New drivers:
- WiFi driver for Realtek 8852AE 802.11ax devices (rtw89)
- Ethernet driver for ASIX AX88796C SPI device (x88796c)
Drivers:
- Broadcom PHYs
- support 72165, 7712 16nm PHYs
- support IDDQ-SR for additional power savings
- PHY support for QCA8081, QCA9561 PHYs
- NXP DPAA2: support for IRQ coalescing
- NXP Ethernet (enetc): support for software TCP segmentation
- Renesas Ethernet (ravb) - support DMAC and EMAC blocks of
Gigabit-capable IP found on RZ/G2L SoC
- Intel 100G Ethernet
- support for eswitch offload of TC/OvS flow API, including
offload of GRE, VxLAN, Geneve tunneling
- support application device queues - ability to assign Rx and Tx
queues to application threads
- PTP and PPS (pulse-per-second) extensions
- Broadcom Ethernet (bnxt)
- devlink health reporting and device reload extensions
- Mellanox Ethernet (mlx5)
- offload macvlan interfaces
- support HW offload of TC rules involving OVS internal ports
- support HW-GRO and header/data split
- support application device queues
- Marvell OcteonTx2:
- add XDP support for PF
- add PTP support for VF
- Qualcomm Ethernet switch (qca8k): support for QCA8328
- Realtek Ethernet DSA switch (rtl8366rb)
- support bridge offload
- support STP, fast aging, disabling address learning
- support for Realtek RTL8365MB-VC, a 4+1 port 10M/100M/1GE switch
- Mellanox Ethernet/IB switch (mlxsw)
- multi-level qdisc hierarchy offload (e.g. RED, prio and shaping)
- offload root TBF qdisc as port shaper
- support multiple routing interface MAC address prefixes
- support for IP-in-IP with IPv6 underlay
- MediaTek WiFi (mt76)
- mt7921 - ASPM, 6GHz, SDIO and testmode support
- mt7915 - LED and TWT support
- Qualcomm WiFi (ath11k)
- include channel rx and tx time in survey dump statistics
- support for 80P80 and 160 MHz bandwidths
- support channel 2 in 6 GHz band
- spectral scan support for QCN9074
- support for rx decapsulation offload (data frames in 802.3
format)
- Qualcomm phone SoC WiFi (wcn36xx)
- enable Idle Mode Power Save (IMPS) to reduce power consumption
during idle
- Bluetooth driver support for MediaTek MT7922 and MT7921
- Enable support for AOSP Bluetooth extension in Qualcomm WCN399x
and Realtek 8822C/8852A
- Microsoft vNIC driver (mana)
- support hibernation and kexec
- Google vNIC driver (gve)
- support for jumbo frames
- implement Rx page reuse
Refactor:
- Make all writes to netdev->dev_addr go thru helpers, so that we
can add this address to the address rbtree and handle the updates
- Various TCP cleanups and optimizations including improvements
to CPU cache use
- Simplify the gnet_stats, Qdisc stats' handling and remove
qdisc->running sequence counter
- Driver changes and API updates to address devlink locking
deficiencies
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'net-next-for-5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from Jakub Kicinski:
"Core:
- Remove socket skb caches
- Add a SO_RESERVE_MEM socket op to forward allocate buffer space and
avoid memory accounting overhead on each message sent
- Introduce managed neighbor entries - added by control plane and
resolved by the kernel for use in acceleration paths (BPF / XDP
right now, HW offload users will benefit as well)
- Make neighbor eviction on link down controllable by userspace to
work around WiFi networks with bad roaming implementations
- vrf: Rework interaction with netfilter/conntrack
- fq_codel: implement L4S style ce_threshold_ect1 marking
- sch: Eliminate unnecessary RCU waits in mini_qdisc_pair_swap()
BPF:
- Add support for new btf kind BTF_KIND_TAG, arbitrary type tagging
as implemented in LLVM14
- Introduce bpf_get_branch_snapshot() to capture Last Branch Records
- Implement variadic trace_printk helper
- Add a new Bloomfilter map type
- Track <8-byte scalar spill and refill
- Access hw timestamp through BPF's __sk_buff
- Disallow unprivileged BPF by default
- Document BPF licensing
Netfilter:
- Introduce egress hook for looking at raw outgoing packets
- Allow matching on and modifying inner headers / payload data
- Add NFT_META_IFTYPE to match on the interface type either from
ingress or egress
Protocols:
- Multi-Path TCP:
- increase default max additional subflows to 2
- rework forward memory allocation
- add getsockopts: MPTCP_INFO, MPTCP_TCPINFO, MPTCP_SUBFLOW_ADDRS
- MCTP flow support allowing lower layer drivers to configure msg
muxing as needed
- Automatic Multicast Tunneling (AMT) driver based on RFC7450
- HSR support the redbox supervision frames (IEC-62439-3:2018)
- Support for the ip6ip6 encapsulation of IOAM
- Netlink interface for CAN-FD's Transmitter Delay Compensation
- Support SMC-Rv2 eliminating the current same-subnet restriction, by
exploiting the UDP encapsulation feature of RoCE adapters
- TLS: add SM4 GCM/CCM crypto support
- Bluetooth: initial support for link quality and audio/codec offload
Driver APIs:
- Add a batched interface for RX buffer allocation in AF_XDP buffer
pool
- ethtool: Add ability to control transceiver modules' power mode
- phy: Introduce supported interfaces bitmap to express MAC
capabilities and simplify PHY code
- Drop rtnl_lock from DSA .port_fdb_{add,del} callbacks
New drivers:
- WiFi driver for Realtek 8852AE 802.11ax devices (rtw89)
- Ethernet driver for ASIX AX88796C SPI device (x88796c)
Drivers:
- Broadcom PHYs
- support 72165, 7712 16nm PHYs
- support IDDQ-SR for additional power savings
- PHY support for QCA8081, QCA9561 PHYs
- NXP DPAA2: support for IRQ coalescing
- NXP Ethernet (enetc): support for software TCP segmentation
- Renesas Ethernet (ravb) - support DMAC and EMAC blocks of
Gigabit-capable IP found on RZ/G2L SoC
- Intel 100G Ethernet
- support for eswitch offload of TC/OvS flow API, including
offload of GRE, VxLAN, Geneve tunneling
- support application device queues - ability to assign Rx and Tx
queues to application threads
- PTP and PPS (pulse-per-second) extensions
- Broadcom Ethernet (bnxt)
- devlink health reporting and device reload extensions
- Mellanox Ethernet (mlx5)
- offload macvlan interfaces
- support HW offload of TC rules involving OVS internal ports
- support HW-GRO and header/data split
- support application device queues
- Marvell OcteonTx2:
- add XDP support for PF
- add PTP support for VF
- Qualcomm Ethernet switch (qca8k): support for QCA8328
- Realtek Ethernet DSA switch (rtl8366rb)
- support bridge offload
- support STP, fast aging, disabling address learning
- support for Realtek RTL8365MB-VC, a 4+1 port 10M/100M/1GE switch
- Mellanox Ethernet/IB switch (mlxsw)
- multi-level qdisc hierarchy offload (e.g. RED, prio and shaping)
- offload root TBF qdisc as port shaper
- support multiple routing interface MAC address prefixes
- support for IP-in-IP with IPv6 underlay
- MediaTek WiFi (mt76)
- mt7921 - ASPM, 6GHz, SDIO and testmode support
- mt7915 - LED and TWT support
- Qualcomm WiFi (ath11k)
- include channel rx and tx time in survey dump statistics
- support for 80P80 and 160 MHz bandwidths
- support channel 2 in 6 GHz band
- spectral scan support for QCN9074
- support for rx decapsulation offload (data frames in 802.3
format)
- Qualcomm phone SoC WiFi (wcn36xx)
- enable Idle Mode Power Save (IMPS) to reduce power consumption
during idle
- Bluetooth driver support for MediaTek MT7922 and MT7921
- Enable support for AOSP Bluetooth extension in Qualcomm WCN399x and
Realtek 8822C/8852A
- Microsoft vNIC driver (mana)
- support hibernation and kexec
- Google vNIC driver (gve)
- support for jumbo frames
- implement Rx page reuse
Refactor:
- Make all writes to netdev->dev_addr go thru helpers, so that we can
add this address to the address rbtree and handle the updates
- Various TCP cleanups and optimizations including improvements to
CPU cache use
- Simplify the gnet_stats, Qdisc stats' handling and remove
qdisc->running sequence counter
- Driver changes and API updates to address devlink locking
deficiencies"
* tag 'net-next-for-5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2122 commits)
Revert "net: avoid double accounting for pure zerocopy skbs"
selftests: net: add arp_ndisc_evict_nocarrier
net: ndisc: introduce ndisc_evict_nocarrier sysctl parameter
net: arp: introduce arp_evict_nocarrier sysctl parameter
libbpf: Deprecate AF_XDP support
kbuild: Unify options for BTF generation for vmlinux and modules
selftests/bpf: Add a testcase for 64-bit bounds propagation issue.
bpf: Fix propagation of signed bounds from 64-bit min/max into 32-bit.
bpf: Fix propagation of bounds from 64-bit min/max into 32-bit and var_off.
net: vmxnet3: remove multiple false checks in vmxnet3_ethtool.c
net: avoid double accounting for pure zerocopy skbs
tcp: rename sk_wmem_free_skb
netdevsim: fix uninit value in nsim_drv_configure_vfs()
selftests/bpf: Fix also no-alu32 strobemeta selftest
bpf: Add missing map_delete_elem method to bloom filter map
selftests/bpf: Add bloom map success test for userspace calls
bpf: Add alignment padding for "map_extra" + consolidate holes
bpf: Bloom filter map naming fixups
selftests/bpf: Add test cases for struct_ops prog
bpf: Add dummy BPF STRUCT_OPS for test purpose
...
- kprobes: Restructured stack unwinder to show properly on x86 when a stack
dump happens from a kretprobe callback.
- Fix to bootconfig parsing
- Have tracefs allow owner and group permissions by default (only denying
others). There's been pressure to allow non root to tracefs in a
controlled fashion, and using groups is probably the safest.
- Bootconfig memory managament updates.
- Bootconfig clean up to have the tools directory be less dependent on
changes in the kernel tree.
- Allow perf to be traced by function tracer.
- Rewrite of function graph tracer to be a callback from the function tracer
instead of having its own trampoline (this change will happen on an arch
by arch basis, and currently only x86_64 implements it).
- Allow multiple direct trampolines (bpf hooks to functions) be batched
together in one synchronization.
- Allow histogram triggers to add variables that can perform calculations
against the event's fields.
- Use the linker to determine architecture callbacks from the ftrace
trampoline to allow for proper parameter prototypes and prevent warnings
from the compiler.
- Extend histogram triggers to key off of variables.
- Have trace recursion use bit magic to determine preempt context over if
branches.
- Have trace recursion disable preemption as all use cases do anyway.
- Added testing for verification of tracing utilities.
- Various small clean ups and fixes.
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Merge tag 'trace-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing updates from Steven Rostedt:
- kprobes: Restructured stack unwinder to show properly on x86 when a
stack dump happens from a kretprobe callback.
- Fix to bootconfig parsing
- Have tracefs allow owner and group permissions by default (only
denying others). There's been pressure to allow non root to tracefs
in a controlled fashion, and using groups is probably the safest.
- Bootconfig memory managament updates.
- Bootconfig clean up to have the tools directory be less dependent on
changes in the kernel tree.
- Allow perf to be traced by function tracer.
- Rewrite of function graph tracer to be a callback from the function
tracer instead of having its own trampoline (this change will happen
on an arch by arch basis, and currently only x86_64 implements it).
- Allow multiple direct trampolines (bpf hooks to functions) be batched
together in one synchronization.
- Allow histogram triggers to add variables that can perform
calculations against the event's fields.
- Use the linker to determine architecture callbacks from the ftrace
trampoline to allow for proper parameter prototypes and prevent
warnings from the compiler.
- Extend histogram triggers to key off of variables.
- Have trace recursion use bit magic to determine preempt context over
if branches.
- Have trace recursion disable preemption as all use cases do anyway.
- Added testing for verification of tracing utilities.
- Various small clean ups and fixes.
* tag 'trace-v5.16' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (101 commits)
tracing/histogram: Fix semicolon.cocci warnings
tracing/histogram: Fix documentation inline emphasis warning
tracing: Increase PERF_MAX_TRACE_SIZE to handle Sentinel1 and docker together
tracing: Show size of requested perf buffer
bootconfig: Initialize ret in xbc_parse_tree()
ftrace: do CPU checking after preemption disabled
ftrace: disable preemption when recursion locked
tracing/histogram: Document expression arithmetic and constants
tracing/histogram: Optimize division by a power of 2
tracing/histogram: Covert expr to const if both operands are constants
tracing/histogram: Simplify handling of .sym-offset in expressions
tracing: Fix operator precedence for hist triggers expression
tracing: Add division and multiplication support for hist triggers
tracing: Add support for creating hist trigger variables from literal
selftests/ftrace: Stop tracing while reading the trace file by default
MAINTAINERS: Update KPROBES and TRACING entries
test_kprobes: Move it from kernel/ to lib/
docs, kprobes: Remove invalid URL and add new reference
samples/kretprobes: Fix return value if register_kretprobe() failed
lib/bootconfig: Fix the xbc_get_info kerneldoc
...
Alexei Starovoitov says:
====================
pull-request: bpf-next 2021-11-01
We've added 181 non-merge commits during the last 28 day(s) which contain
a total of 280 files changed, 11791 insertions(+), 5879 deletions(-).
The main changes are:
1) Fix bpf verifier propagation of 64-bit bounds, from Alexei.
2) Parallelize bpf test_progs, from Yucong and Andrii.
3) Deprecate various libbpf apis including af_xdp, from Andrii, Hengqi, Magnus.
4) Improve bpf selftests on s390, from Ilya.
5) bloomfilter bpf map type, from Joanne.
6) Big improvements to JIT tests especially on Mips, from Johan.
7) Support kernel module function calls from bpf, from Kumar.
8) Support typeless and weak ksym in light skeleton, from Kumar.
9) Disallow unprivileged bpf by default, from Pawan.
10) BTF_KIND_DECL_TAG support, from Yonghong.
11) Various bpftool cleanups, from Quentin.
* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (181 commits)
libbpf: Deprecate AF_XDP support
kbuild: Unify options for BTF generation for vmlinux and modules
selftests/bpf: Add a testcase for 64-bit bounds propagation issue.
bpf: Fix propagation of signed bounds from 64-bit min/max into 32-bit.
bpf: Fix propagation of bounds from 64-bit min/max into 32-bit and var_off.
selftests/bpf: Fix also no-alu32 strobemeta selftest
bpf: Add missing map_delete_elem method to bloom filter map
selftests/bpf: Add bloom map success test for userspace calls
bpf: Add alignment padding for "map_extra" + consolidate holes
bpf: Bloom filter map naming fixups
selftests/bpf: Add test cases for struct_ops prog
bpf: Add dummy BPF STRUCT_OPS for test purpose
bpf: Factor out helpers for ctx access checking
bpf: Factor out a helper to prepare trampoline for struct_ops prog
selftests, bpf: Fix broken riscv build
riscv, libbpf: Add RISC-V (RV64) support to bpf_tracing.h
tools, build: Add RISC-V to HOSTARCH parsing
riscv, bpf: Increase the maximum number of iterations
selftests, bpf: Add one test for sockmap with strparser
selftests, bpf: Fix test_txmsg_ingress_parser error
...
====================
Link: https://lore.kernel.org/r/20211102013123.9005-1-alexei.starovoitov@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
If the divisor is a constant use specific division functions to
avoid extra branches when the trigger is hit.
If the divisor constant but not a power of 2, the division can be
replaced with a multiplication and shift in the following case:
Let X = dividend and Y = divisor.
Choose Z = some power of 2. If Y <= Z, then:
X / Y = (X * (Z / Y)) / Z
(Z / Y) is a constant (mult) which is calculated at parse time, so:
X / Y = (X * mult) / Z
The division by Z can be replaced by a shift since Z is a power of 2:
X / Y = (X * mult) >> shift
As long, as X < Z the results will not be off by more than 1.
Link: https://lkml.kernel.org/r/20211029232410.3494196-1-kaleshsingh@google.com
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Remove CONFIG_PREEMPT_RT from inside functions, avoiding
compilation problems in the future.
Link: https://lkml.kernel.org/r/37ee0881b033cdc513efc84ebea26cf77880c8c2.1635702894.git.bristot@kernel.org
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Tom Zanussi <zanussi@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: linux-rt-users@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Remove CONFIG_STACKTRACE from inside functions, avoiding
compilation problems in the future.
Link: https://lkml.kernel.org/r/3465cca2f28e1ba602a1fc8bdb28d12950b5226e.1635702894.git.bristot@kernel.org
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Tom Zanussi <zanussi@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: linux-rt-users@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Currently, the user can start only one instance of timerlat/osnoise
tracers and the tracers cannot run in parallel.
As starting point to add more flexibility, let's allow the same tracer to
run on different trace instances. The workload will start when the first
trace_array (instance) is registered and stop when the last instance
is unregistered.
So, while this patch allows the same tracer to run in multiple
instances (e.g., two instances running osnoise), it still does not allow
instances of timerlat and osnoise in parallel (e.g., one timerlat and
osnoise). That is because the osnoise: events have different behavior
depending on which tracer is enabled (osnoise or timerlat). Enabling
the parallel usage of these two tracers is in my TODO list.
Link: https://lkml.kernel.org/r/38c8f14b613492a4f3f938d9d3bf0b063b72f0f0.1635702894.git.bristot@kernel.org
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Tom Zanussi <zanussi@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: linux-rt-users@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Remove CONFIG_TIMERLAT_TRACER from inside functions, avoiding
compilation problems in the future.
Link: https://lkml.kernel.org/r/8245abb5a112d249f5da6c1df499244ad9e647bc.1635702894.git.bristot@kernel.org
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Tom Zanussi <zanussi@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: linux-rt-users@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
osnoise/timerlat were built to run a single instance, and for this,
a single variable is enough to store the current struct trace_array
*tr with information about the tracing instance. This is done via
the *osnoise_trace variable. A trace_array represents a trace instance.
In preparation to support multiple instances, replace the
*osnoise_trace variable with an RCU protected list of instances.
The operations that refer to an instance now propagate to all
elements of the list (all instances).
Also, replace the osnoise_busy variable with a check if the list
has elements (busy).
No functional change is expected with this patch, i.e., only one
instance is allowed yet.
Link: https://lkml.kernel.org/r/91d006e889b9a5d1ff258fe6077f021ae3f26372.1635702894.git.bristot@kernel.org
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Tom Zanussi <zanussi@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: linux-rt-users@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
When writing a new CPU mask via osnoise/cpus, if the tracer is running,
the workload is restarted to follow the new cpumask. The restart is
currently done using osnoise_workload_start/stop(), which disables the
workload *and* the instrumentation. However, disabling the
instrumentation is not necessary.
Calling start/stop_per_cpu_kthreads() is enough to apply the new
osnoise/cpus config.
Link: https://lkml.kernel.org/r/ee633e82867c5b88851aa6040522a799c0034486.1635702894.git.bristot@kernel.org
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Tom Zanussi <zanussi@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: linux-rt-users@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
In preparation from supporting multiple trace instances, create
workload start/stop specific functions.
No functional change.
Link: https://lkml.kernel.org/r/74b090971e9acdd13625be1c28ef3270d2275e77.1635702894.git.bristot@kernel.org
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Tom Zanussi <zanussi@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: linux-rt-users@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
trace_osnoise_callback_enabled is used by ftrace_nmi_enter/exit()
to know when to call the NMI callback. The barrier is used to
avoid having callbacks enabled before the resetting date during
the start or to touch the values after stopping the tracer.
Link: https://lkml.kernel.org/r/a413b8f14aa9312fbd1ba99f96225a8aed831053.1635702894.git.bristot@kernel.org
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Tom Zanussi <zanussi@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: linux-rt-users@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
In preparation to support multiple instances, decouple the
osnoise/timelat workload from instance-specific tracing_cpumask.
Different instances can have conflicting cpumasks, making osnoise
workload management needlessly complex. Osnoise already has its
global cpumask.
I also thought about using the first instance mask, but the
"first" instance could be removed before the others.
This also fixes the problem that changing the tracing_mask was not
re-starting the trace.
Link: https://lkml.kernel.org/r/169a71bcc919ce3ab53ae6f9ca5cde57fffaf9c6.1635702894.git.bristot@kernel.org
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Tom Zanussi <zanussi@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: linux-rt-users@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Factor out two helpers to check the read access of ctx for raw tp
and BTF function. bpf_tracing_ctx_access() is used to check
the read access to argument is valid, and bpf_tracing_btf_ctx_access()
checks whether the btf type of argument is valid besides the checking
of argument read. bpf_tracing_btf_ctx_access() will be used by the
following patch.
Signed-off-by: Hou Tao <houtao1@huawei.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20211025064025.2567443-3-houtao1@huawei.com
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Merge tag 'for-5.16/block-2021-10-29' of git://git.kernel.dk/linux-block
Pull block updates from Jens Axboe:
- mq-deadline accounting improvements (Bart)
- blk-wbt timer fix (Andrea)
- Untangle the block layer includes (Christoph)
- Rework the poll support to be bio based, which will enable adding
support for polling for bio based drivers (Christoph)
- Block layer core support for multi-actuator drives (Damien)
- blk-crypto improvements (Eric)
- Batched tag allocation support (me)
- Request completion batching support (me)
- Plugging improvements (me)
- Shared tag set improvements (John)
- Concurrent queue quiesce support (Ming)
- Cache bdev in ->private_data for block devices (Pavel)
- bdev dio improvements (Pavel)
- Block device invalidation and block size improvements (Xie)
- Various cleanups, fixes, and improvements (Christoph, Jackie,
Masahira, Tejun, Yu, Pavel, Zheng, me)
* tag 'for-5.16/block-2021-10-29' of git://git.kernel.dk/linux-block: (174 commits)
blk-mq-debugfs: Show active requests per queue for shared tags
block: improve readability of blk_mq_end_request_batch()
virtio-blk: Use blk_validate_block_size() to validate block size
loop: Use blk_validate_block_size() to validate block size
nbd: Use blk_validate_block_size() to validate block size
block: Add a helper to validate the block size
block: re-flow blk_mq_rq_ctx_init()
block: prefetch request to be initialized
block: pass in blk_mq_tags to blk_mq_rq_ctx_init()
block: add rq_flags to struct blk_mq_alloc_data
block: add async version of bio_set_polled
block: kill DIO_MULTI_BIO
block: kill unused polling bits in __blkdev_direct_IO()
block: avoid extra iter advance with async iocb
block: Add independent access ranges support
blk-mq: don't issue request directly in case that current is to be blocked
sbitmap: silence data race warning
blk-cgroup: synchronize blkg creation against policy deactivation
block: refactor bio_iov_bvec_set()
block: add single bio async direct IO helper
...
Some functions had kernel-doc that used a comma instead of a hash to
separate the function name from the one line description.
Also, the "ftrace_is_dead()" had an incomplete description.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
When the syscall trace points are not configured in, the kselftests for
ftrace will try to attach an event probe (eprobe) to one of the system
call trace points. This triggered a WARNING, because the failure only
expects to see memory issues. But this is not the only failure. The user
may attempt to attach to a non existent event, and the kernel must not
warn about it.
Link: https://lkml.kernel.org/r/20211027120854.0680aa0f@gandalf.local.home
Fixes: 7491e2c442 ("tracing: Add a probe that attaches to trace events")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
If the perf buffer isn't large enough, provide a hint about how large it
needs to be for whatever is running.
Link: https://lkml.kernel.org/r/20210831043723.13481-1-robbat2@gentoo.org
Signed-off-by: Robin H. Johnson <robbat2@gentoo.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
With CONFIG_DEBUG_PREEMPT we observed reports like:
BUG: using smp_processor_id() in preemptible
caller is perf_ftrace_function_call+0x6f/0x2e0
CPU: 1 PID: 680 Comm: a.out Not tainted
Call Trace:
<TASK>
dump_stack_lvl+0x8d/0xcf
check_preemption_disabled+0x104/0x110
? optimize_nops.isra.7+0x230/0x230
? text_poke_bp_batch+0x9f/0x310
perf_ftrace_function_call+0x6f/0x2e0
...
__text_poke+0x5/0x620
text_poke_bp_batch+0x9f/0x310
This telling us the CPU could be changed after task is preempted, and
the checking on CPU before preemption will be invalid.
Since now ftrace_test_recursion_trylock() will help to disable the
preemption, this patch just do the checking after trylock() to address
the issue.
Link: https://lkml.kernel.org/r/54880691-5fe2-33e7-d12f-1fa6136f5183@linux.alibaba.com
CC: Steven Rostedt <rostedt@goodmis.org>
Cc: Guo Ren <guoren@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Miroslav Benes <mbenes@suse.cz>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Joe Lawrence <joe.lawrence@redhat.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Jisheng Zhang <jszhang@kernel.org>
Reported-by: Abaci <abaci@linux.alibaba.com>
Signed-off-by: Michael Wang <yun.wang@linux.alibaba.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
As the documentation explained, ftrace_test_recursion_trylock()
and ftrace_test_recursion_unlock() were supposed to disable and
enable preemption properly, however currently this work is done
outside of the function, which could be missing by mistake.
And since the internal using of trace_test_and_set_recursion()
and trace_clear_recursion() also require preemption disabled, we
can just merge the logical.
This patch will make sure the preemption has been disabled when
trace_test_and_set_recursion() return bit >= 0, and
trace_clear_recursion() will enable the preemption if previously
enabled.
Link: https://lkml.kernel.org/r/13bde807-779c-aa4c-0672-20515ae365ea@linux.alibaba.com
CC: Petr Mladek <pmladek@suse.com>
Cc: Guo Ren <guoren@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <James.Bottomley@HansenPartnership.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Joe Lawrence <joe.lawrence@redhat.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Jisheng Zhang <jszhang@kernel.org>
CC: Steven Rostedt <rostedt@goodmis.org>
CC: Miroslav Benes <mbenes@suse.cz>
Reported-by: Abaci <abaci@linux.alibaba.com>
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Michael Wang <yun.wang@linux.alibaba.com>
[ Removed extra line in comment - SDR ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The division is a slow operation. If the divisor is a power of 2, use a
shift instead.
Results were obtained using Android's version of perf (simpleperf[1]) as
described below:
1. hist_field_div() is modified to call 2 test functions:
test_hist_field_div_[not]_optimized(); passing them the
same args. Use noinline and volatile to ensure these are
not optimized out by the compiler.
2. Create a hist event trigger that uses division:
events/kmem/rss_stat$ echo 'hist:keys=common_pid:x=size/<divisor>'
>> trigger
events/kmem/rss_stat$ echo 'hist:keys=common_pid:vals=$x'
>> trigger
3. Run Android's lmkd_test[2] to generate rss_stat events, and
record CPU samples with Android's simpleperf:
simpleperf record -a --exclude-perf --post-unwind=yes -m 16384 -g
-f 2000 -o perf.data
== Results ==
Divisor is a power of 2 (divisor == 32):
test_hist_field_div_not_optimized | 8,717,091 cpu-cycles
test_hist_field_div_optimized | 1,643,137 cpu-cycles
If the divisor is a power of 2, the optimized version is ~5.3x faster.
Divisor is not a power of 2 (divisor == 33):
test_hist_field_div_not_optimized | 4,444,324 cpu-cycles
test_hist_field_div_optimized | 5,497,958 cpu-cycles
If the divisor is not a power of 2, as expected, the optimized version is
slightly slower (~24% slower).
[1] https://android.googlesource.com/platform/system/extras/+/master/simpleperf/doc/README.md
[2] https://cs.android.com/android/platform/superproject/+/master:system/memory/lmkd/tests/lmkd_test.cpp
Link: https://lkml.kernel.org/r/20211025200852.3002369-7-kaleshsingh@google.com
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
If both operands of a hist trigger expression are constants, convert the
expression to a constant. This optimization avoids having to perform the
same calculation multiple times and also saves on memory since the
merged constants are represented by a single struct hist_field instead
or multiple.
Link: https://lkml.kernel.org/r/20211025200852.3002369-6-kaleshsingh@google.com
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The '-' in .sym-offset can confuse the hist trigger arithmetic
expression parsing. Simplify the handling of this by replacing the
'sym-offset' with 'symXoffset'. This allows us to correctly evaluate
expressions where the user may have inadvertently added a .sym-offset
modifier to one of the operands in an expression, instead of bailing
out. In this case the .sym-offset has no effect on the evaluation of the
expression. The only valid use of the .sym-offset is as a hist key
modifier.
Link: https://lkml.kernel.org/r/20211025200852.3002369-5-kaleshsingh@google.com
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The current histogram expression evaluation logic evaluates the
expression from right to left. This can lead to incorrect results
if the operations are not associative (as is the case for subtraction
and, the now added, division operators).
e.g. 16-8-4-2 should be 2 not 10 --> 16-8-4-2 = ((16-8)-4)-2
64/8/4/2 should be 1 not 16 --> 64/8/4/2 = ((64/8)/4)/2
Division and multiplication are currently limited to single operation
expression due to operator precedence support not yet implemented.
Rework the expression parsing to support the correct evaluation of
expressions containing operators of different precedences; and fix
the associativity error by evaluating expressions with operators of
the same precedence from left to right.
Examples:
(1) echo 'hist:keys=common_pid:a=8,b=4,c=2,d=1,w=$a-$b-$c-$d' \
>> event/trigger
(2) echo 'hist:keys=common_pid:x=$a/$b/3/2' >> event/trigger
(3) echo 'hist:keys=common_pid:y=$a+10/$c*1024' >> event/trigger
(4) echo 'hist:keys=common_pid:z=$a/$b+$c*$d' >> event/trigger
Link: https://lkml.kernel.org/r/20211025200852.3002369-4-kaleshsingh@google.com
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
Reviewed-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Adds basic support for division and multiplication operations for
hist trigger variable expressions.
For simplicity this patch only supports, division and multiplication
for a single operation expression (e.g. x=$a/$b), as currently
expressions are always evaluated right to left. This can lead to some
incorrect results:
e.g. echo 'hist:keys=common_pid:x=8-4-2' >> event/trigger
8-4-2 should evaluate to 2 i.e. (8-4)-2
but currently x evaluate to 6 i.e. 8-(4-2)
Multiplication and division in sub-expressions will work correctly, once
correct operator precedence support is added (See next patch in this
series).
For the undefined case of division by 0, the histogram expression
evaluates to (u64)(-1). Since this cannot be detected when the
expression is created, it is the responsibility of the user to be
aware and account for this possibility.
Examples:
echo 'hist:keys=common_pid:a=8,b=4,x=$a/$b' \
>> event/trigger
echo 'hist:keys=common_pid:y=5*$b' \
>> event/trigger
Link: https://lkml.kernel.org/r/20211025200852.3002369-3-kaleshsingh@google.com
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Currently hist trigger expressions don't support the use of numeric
literals:
e.g. echo 'hist:keys=common_pid:x=$y-1234'
--> is not valid expression syntax
Having the ability to use numeric constants in hist triggers supports
a wider range of expressions for creating variables.
Add support for creating trace event histogram variables from numeric
literals.
e.g. echo 'hist:keys=common_pid:x=1234,y=size-1024' >> event/trigger
A negative numeric constant is created, using unary minus operator
(parentheses are required).
e.g. echo 'hist:keys=common_pid:z=-(2)' >> event/trigger
Constants can be used with division/multiplication (added in the
next patch in this series) to implement granularity filters for frequent
trace events. For instance we can limit emitting the rss_stat
trace event to when there is a 512KB cross over in the rss size:
# Create a synthetic event to monitor instead of the high frequency
# rss_stat event
echo 'rss_stat_throttled unsigned int mm_id; unsigned int curr;
int member; long size' >> tracing/synthetic_events
# Create a hist trigger that emits the synthetic rss_stat_throttled
# event only when the rss size crosses a 512KB boundary.
echo 'hist:keys=keys=mm_id,member:bucket=size/0x80000:onchange($bucket)
.rss_stat_throttled(mm_id,curr,member,size)'
>> events/kmem/rss_stat/trigger
A use case for using constants with addition/subtraction is not yet
known, but for completeness the use of constants are supported for all
operators.
Link: https://lkml.kernel.org/r/20211025200852.3002369-2-kaleshsingh@google.com
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The sparse tool complains as follows:
kernel/trace/trace_hwlat.c:82:27: warning: symbol 'hwlat_single_cpu_data' was not declared. Should it be static?
kernel/trace/trace_hwlat.c:83:1: warning: symbol '__pcpu_scope_hwlat_per_cpu_data' was not declared. Should it be static?
This symbol is not used outside of trace_hwlat.c, so this commit
marks it static.
Link: https://lkml.kernel.org/r/20211021035225.1050685-1-bobo.shaobowang@huawei.com
Signed-off-by: Wang ShaoBo <bobo.shaobowang@huawei.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Since "54357f0c9149 tracing: Add migrate-disabled counter to tracing
output," the migrate disabled field is also printed in the !PREEMPR_RT
kernel config. While this information was added to the vast majority of
tracers, osnoise and timerlat were not updated (because they are new
tracers).
Fix timerlat header by adding the information about migrate disabled.
Link: https://lkml.kernel.org/r/bc0c234ab49946cdd63effa6584e1d5e8662cb44.1634308385.git.bristot@kernel.org
Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: x86@kernel.org
Cc: linux-doc@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Fixes: 54357f0c91 ("tracing: Add migrate-disabled counter to tracing output.")
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Since "54357f0c9149 tracing: Add migrate-disabled counter to tracing
output," the migrate disabled field is also printed in the !PREEMPR_RT
kernel config. While this information was added to the vast majority of
tracers, osnoise and timerlat were not updated (because they are new
tracers).
Fix osnoise header by adding the information about migrate disabled.
Link: https://lkml.kernel.org/r/9cb3d54e29e0588dbba12e81486bd8a09adcd8ca.1634308385.git.bristot@kernel.org
Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: x86@kernel.org
Cc: linux-doc@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Fixes: 54357f0c91 ("tracing: Add migrate-disabled counter to tracing output.")
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
This symbol is not used outside of ftrace.c, so marks it static.
Fixes the following sparse warning:
kernel/trace/ftrace.c:579:5: warning: symbol 'ftrace_profile_pages_init'
was not declared. Should it be static?
Link: https://lkml.kernel.org/r/1634640534-18280-1-git-send-email-jiapeng.chong@linux.alibaba.com
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Fixes: cafb168a1c ("tracing: make the function profiler per cpu")
Signed-off-by: chongjiapeng <jiapeng.chong@linux.alibaba.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The helper is used in tracing programs to cast a socket
pointer to a unix_sock pointer.
The return value could be NULL if the casting is illegal.
Suggested-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20211021134752.1223426-2-hengqi.chen@gmail.com
clang started warning about excessive stack usage in
hist_trigger_print_key()
kernel/trace/trace_events_hist.c:4723:13: error: stack frame size (1336) exceeds limit (1024) in function 'hist_trigger_print_key' [-Werror,-Wframe-larger-than]
The problem is that there are two 512-byte arrays on the stack if
hist_trigger_stacktrace_print() gets inlined. I don't think this has
changed in the past five years, but something probably changed the
inlining decisions made by the compiler, so the problem is now made
more obvious.
Rather than printing the symbol names into separate buffers, it
seems we can simply use the special %ps format string modifier
to print the pointers symbolically and get rid of both buffers.
Marking hist_trigger_stacktrace_print() would be a simpler
way of avoiding the warning, but that would not address the
excessive stack usage.
Link: https://lkml.kernel.org/r/20211019153337.294790-1-arnd@kernel.org
Fixes: 69a0200c2e ("tracing: Add hist trigger support for stacktraces as keys")
Link: https://lore.kernel.org/all/20211015095704.49a99859@gandalf.local.home/
Reviewed-by: Tom Zanussi <zanussi@kernel.org>
Tested-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Currently to switch a set of "multi" direct trampolines from one
trampoline to another, a full shutdown of the current set needs to be
done, followed by an update to what trampoline the direct callers would
call, and then re-enabling the callers. This leaves a time when the
functions will not be calling anything, and events may be missed.
Instead, use a trick to allow all the functions with direct trampolines
attached will always call either the new or old trampoline while the
switch is happening. To do this, first attach a "dummy" callback via
ftrace to all the functions that the current direct trampoline is attached
to. This will cause the functions to call the "list func" instead of the
direct trampoline. The list function will call the direct trampoline
"helper" that will set the function it should call as it returns back to
the ftrace trampoline.
At this moment, the direct caller descriptor can safely update the direct
call trampoline. The list function will pick either the new or old
function (depending on the memory coherency model of the architecture).
Now removing the dummy function from each of the locations of the direct
trampoline caller, will put back the direct call, but now to the new
trampoline.
A better visual is:
[ Changing direct call from my_direct_1 to my_direct_2 ]
<traced_func>:
call my_direct_1
||||||||||||||||||||
vvvvvvvvvvvvvvvvvvvv
<traced_func>:
call ftrace_caller
<ftrace_caller>:
[..]
call ftrace_ops_list_func
ftrace_ops_list_func()
{
ops->func() -> direct_helper -> set rax to my_direct_1 or my_direct_2
}
call rax (to either my_direct_1 or my_direct_2
||||||||||||||||||||
vvvvvvvvvvvvvvvvvvvv
<traced_func>:
call my_direct_2
Link: https://lore.kernel.org/all/20211014162819.5c85618b@gandalf.local.home/
Acked-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Adding interface to modify registered direct function
for ftrace_ops. Adding following function:
modify_ftrace_direct_multi(struct ftrace_ops *ops, unsigned long addr)
The function changes the currently registered direct
function for all attached functions.
Link: https://lkml.kernel.org/r/20211008091336.33616-8-jolsa@kernel.org
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Adding interface to register multiple direct functions
within single call. Adding following functions:
register_ftrace_direct_multi(struct ftrace_ops *ops, unsigned long addr)
unregister_ftrace_direct_multi(struct ftrace_ops *ops, unsigned long addr)
The register_ftrace_direct_multi registers direct function (addr)
with all functions in ops filter. The ops filter can be updated
before with ftrace_set_filter_ip calls.
All requested functions must not have direct function currently
registered, otherwise register_ftrace_direct_multi will fail.
The unregister_ftrace_direct_multi unregisters ops related direct
functions.
Link: https://lkml.kernel.org/r/20211008091336.33616-7-jolsa@kernel.org
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Factor out the code that adds (ip, addr) tuple to direct_functions
hash in new ftrace_add_rec_direct function. It will be used in
following patches.
Link: https://lkml.kernel.org/r/20211008091336.33616-6-jolsa@kernel.org
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
There's a new test in trace_selftest_startup_function_graph() that
requires the use of ftrace args being supported as well does some tricks
with dynamic tracing. Although this code checks HAVE_DYNAMIC_FTRACE_WITH_ARGS
it fails to check DYNAMIC_FTRACE, and the kernel fails to build due to
that dependency.
Also only define the prototype of trace_direct_tramp() if it is used.
Link: https://lkml.kernel.org/r/20211021134357.7f48e173@gandalf.local.home
Acked-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Adding selftest for checking that direct trampoline can
co-exist together with graph tracer on same function.
This is supported for CONFIG_HAVE_DYNAMIC_FTRACE_WITH_ARGS
config option, which is defined only for x86_64 for now.
Link: https://lkml.kernel.org/r/20211008091336.33616-5-jolsa@kernel.org
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
We don't need special hook for graph tracer entry point,
but instead we can use graph_ops::func function to install
the return_hooker.
This moves the graph tracing setup _before_ the direct
trampoline prepares the stack, so the return_hooker will
be called when the direct trampoline is finished.
This simplifies the code, because we don't need to take into
account the direct trampoline setup when preparing the graph
tracer hooker and we can allow function graph tracer on entries
registered with direct trampoline.
Link: https://lkml.kernel.org/r/20211008091336.33616-4-jolsa@kernel.org
[fixed compile error reported by kernel test robot <lkp@intel.com>]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Now that there are three different instances of doing the addition trick
to the preempt_count() and NMI_MASK, HARDIRQ_MASK and SOFTIRQ_OFFSET
macros, it deserves a helper function defined in the preempt.h header.
Add the interrupt_context_level() helper and replace the three instances
that do that logic with it.
Link: https://lore.kernel.org/all/20211015142541.4badd8a9@gandalf.local.home/
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Instead of having branches that adds noise to the branch prediction, use
the addition logic to set the bit for the level of interrupt context that
the state is currently in. This copies the logic from perf's
get_recursion_context() function.
Link: https://lore.kernel.org/all/20211015161702.GF174703@worktop.programming.kicks-ass.net/
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
If CONFIG_CFI_CLANG=y, attempting to read an event histogram will cause
the kernel to panic due to failed CFI check.
1. echo 'hist:keys=common_pid' >> events/sched/sched_switch/trigger
2. cat events/sched/sched_switch/hist
3. kernel panics on attempting to read hist
This happens because the sort() function expects a generic
int (*)(const void *, const void *) pointer for the compare function.
To prevent this CFI failure, change tracing map cmp_entries_* function
signatures to match this.
Also, fix the build error reported by the kernel test robot [1].
[1] https://lore.kernel.org/r/202110141140.zzi4dRh4-lkp@intel.com/
Link: https://lkml.kernel.org/r/20211014045217.3265162-1-kaleshsingh@google.com
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
In an effort to enable -Wcast-function-type in the top-level Makefile to
support Control Flow Integrity builds, all function casts need to be
removed.
This means that ftrace_ops_list_func() can no longer be defined as
ftrace_ops_no_ops(). The reason for ftrace_ops_no_ops() is to use that when
an architecture calls ftrace_ops_list_func() with only two parameters
(called from assembly). And to make sure there's no C side-effects, those
archs call ftrace_ops_no_ops() which only has two parameters, as
ftrace_ops_list_func() has four parameters.
Instead of a typecast, use vmlinux.lds.h to define ftrace_ops_list_func() to
arch_ftrace_ops_list_func() that will define the proper set of parameters.
Link: https://lore.kernel.org/r/20200614070154.6039-1-oscar.carter@gmx.com
Link: https://lkml.kernel.org/r/20200617165616.52241bde@oasis.local.home
Link: https://lore.kernel.org/all/20211005053922.GA702049@embeddedor/
Requested-by: Oscar Carter <oscar.carter@gmx.com>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
We only need to call it to resolve the blk_status_t -> errno mapping for
tracing, so move the conversion into the tracepoints that are not called
at all when tracing isn't enabled.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
While writing an email explaining the "bit = 0" logic for a discussion on
making ftrace_test_recursion_trylock() disable preemption, I discovered a
path that makes the "not do the logic if bit is zero" unsafe.
The recursion logic is done in hot paths like the function tracer. Thus,
any code executed causes noticeable overhead. Thus, tricks are done to try
to limit the amount of code executed. This included the recursion testing
logic.
Having recursion testing is important, as there are many paths that can
end up in an infinite recursion cycle when tracing every function in the
kernel. Thus protection is needed to prevent that from happening.
Because it is OK to recurse due to different running context levels (e.g.
an interrupt preempts a trace, and then a trace occurs in the interrupt
handler), a set of bits are used to know which context one is in (normal,
softirq, irq and NMI). If a recursion occurs in the same level, it is
prevented*.
Then there are infrastructure levels of recursion as well. When more than
one callback is attached to the same function to trace, it calls a loop
function to iterate over all the callbacks. Both the callbacks and the
loop function have recursion protection. The callbacks use the
"ftrace_test_recursion_trylock()" which has a "function" set of context
bits to test, and the loop function calls the internal
trace_test_and_set_recursion() directly, with an "internal" set of bits.
If an architecture does not implement all the features supported by ftrace
then the callbacks are never called directly, and the loop function is
called instead, which will implement the features of ftrace.
Since both the loop function and the callbacks do recursion protection, it
was seemed unnecessary to do it in both locations. Thus, a trick was made
to have the internal set of recursion bits at a more significant bit
location than the function bits. Then, if any of the higher bits were set,
the logic of the function bits could be skipped, as any new recursion
would first have to go through the loop function.
This is true for architectures that do not support all the ftrace
features, because all functions being traced must first go through the
loop function before going to the callbacks. But this is not true for
architectures that support all the ftrace features. That's because the
loop function could be called due to two callbacks attached to the same
function, but then a recursion function inside the callback could be
called that does not share any other callback, and it will be called
directly.
i.e.
traced_function_1: [ more than one callback tracing it ]
call loop_func
loop_func:
trace_recursion set internal bit
call callback
callback:
trace_recursion [ skipped because internal bit is set, return 0 ]
call traced_function_2
traced_function_2: [ only traced by above callback ]
call callback
callback:
trace_recursion [ skipped because internal bit is set, return 0 ]
call traced_function_2
[ wash, rinse, repeat, BOOM! out of shampoo! ]
Thus, the "bit == 0 skip" trick is not safe, unless the loop function is
call for all functions.
Since we want to encourage architectures to implement all ftrace features,
having them slow down due to this extra logic may encourage the
maintainers to update to the latest ftrace features. And because this
logic is only safe for them, remove it completely.
[*] There is on layer of recursion that is allowed, and that is to allow
for the transition between interrupt context (normal -> softirq ->
irq -> NMI), because a trace may occur before the context update is
visible to the trace recursion logic.
Link: https://lore.kernel.org/all/609b565a-ed6e-a1da-f025-166691b5d994@linux.alibaba.com/
Link: https://lkml.kernel.org/r/20211018154412.09fcad3c@gandalf.local.home
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "James E.J. Bottomley" <James.Bottomley@hansenpartnership.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Miroslav Benes <mbenes@suse.cz>
Cc: Joe Lawrence <joe.lawrence@redhat.com>
Cc: Colin Ian King <colin.king@canonical.com>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Jisheng Zhang <jszhang@kernel.org>
Cc: =?utf-8?b?546L6LSH?= <yun.wang@linux.alibaba.com>
Cc: Guo Ren <guoren@kernel.org>
Cc: stable@vger.kernel.org
Fixes: edc15cafcb ("tracing: Avoid unnecessary multiple recursion checks")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
When an event probe is to be removed via the API that created it via the
dynamic events, an -ENOENT error is returned.
This is because the removal of the event probe does not expect to see the
event system and name that the event probe is attached to, even though
that's part of the API to create it. As the removal of probes is to use
the same API as they are created.
In fact, the removal is not consistent with the kprobes and uprobes
removal. Fix that by allowing various ways to remove the eprobe.
The eprobe is created with:
e:[GROUP/]NAME SYSTEM/EVENT [OPTIONS]
Have it get removed by echoing in the following into dynamic_events:
# Remove all eprobes with NAME
echo '-:NAME' >> dynamic_events
# Remove a specific eprobe
echo '-:GROUP/NAME' >> dynamic_events
echo '-:GROUP/NAME SYSTEM/EVENT' >> dynamic_events
echo '-:NAME SYSTEM/EVENT' >> dynamic_events
echo '-:GROUP/NAME SYSTEM/EVENT OPTIONS' >> dynamic_events
echo '-:NAME SYSTEM/EVENT OPTIONS' >> dynamic_events
Link: https://lkml.kernel.org/r/20211012081925.0e19cc4f@gandalf.local.home
Link: https://lkml.kernel.org/r/20211013205533.630722129@goodmis.org
Suggested-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Fixes: 7491e2c442 ("tracing: Add a probe that attaches to trace events")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Replace the obsolete and ambiguos macro in_irq() with new
macro in_hardirq().
Link: https://lkml.kernel.org/r/20210930000342.6016-1-changbin.du@gmail.com
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Most of ARCHs use empty ftrace_dyn_arch_init(), introduce a weak common
ftrace_dyn_arch_init() to cleanup them.
Link: https://lkml.kernel.org/r/20210909090216.1955240-1-o451686892@gmail.com
Acked-by: Heiko Carstens <hca@linux.ibm.com> (s390)
Acked-by: Helge Deller <deller@gmx.de> (parisc)
Signed-off-by: Weizhao Ouyang <o451686892@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
When building the files in the tracefs file system, do not by default set
any permissions for OTH (other). This will make it easier for admins who
want to define a group for accessing tracefs and not having to first
disable all the permission bits for "other" in the file system.
As tracing can leak sensitive information, it should never by default
allowing all users access. An admin can still set the permission bits for
others to have access, which may be useful for creating a honeypot and
seeing who takes advantage of it and roots the machine.
Link: https://lkml.kernel.org/r/20210818153038.864149276@goodmis.org
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The upper and lower variables are set as link lists to add into the sparse
array. If they are NULL, after the needed allocations are done, then there
is nothing to add. But they need to be initialized to NULL for this to
work.
Link: https://lore.kernel.org/all/221bc7ba-a475-1cb9-1bbe-730bb9c2d448@canonical.com/
Fixes: 8d6e90983a ("tracing: Create a sparse bitmask for pid filtering")
Reported-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The compiler warns when the data are actually unused:
kernel/trace/trace.c:1712:13: error: ‘trace_create_maxlat_file’ defined but not used [-Werror=unused-function]
1712 | static void trace_create_maxlat_file(struct trace_array *tr,
| ^~~~~~~~~~~~~~~~~~~~~~~~
[Why]
CONFIG_HWLAT_TRACER=n, CONFIG_TRACER_MAX_TRACE=n, CONFIG_OSNOISE_TRACER=y
gcc report warns.
[How]
Now trace_create_maxlat_file will only take effect when
CONFIG_HWLAT_TRACER=y or CONFIG_TRACER_MAX_TRACE=y. In fact, after
adding osnoise trace, it also needs to take effect.
Link: https://lore.kernel.org/all/c1d9e328-ad7c-920b-6c24-9e1598a6421c@infradead.org/
Link: https://lkml.kernel.org/r/20210922025122.3268022-1-liu.yun@linux.dev
Fixes: bce29ac9ce ("trace: Add osnoise tracer")
Cc: Daniel Bristot de Oliveira <bristot@redhat.com>
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Reviewed-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org> # build-tested
Signed-off-by: Jackie Liu <liuyun01@kylinos.cn>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
When the trace_pid_list was created, the default pid max was 32768.
Creating a bitmask that can hold one bit for all 32768 took up 4096 (one
page). Having a one page bitmask was not much of a problem, and that was
used for mapping pids. But today, systems are bigger and can run more
tasks, and now the default pid_max is usually set to 4194304. Which means
to handle that many pids requires 524288 bytes. Worse yet, the pid_max can
be set to 2^30 (1073741824 or 1G) which would take 134217728 (128M) of
memory to store this array.
Since the pid_list array is very sparsely populated, it is a huge waste of
memory to store all possible bits for each pid when most will not be set.
Instead, use a page table scheme to store the array, and allow this to
handle up to 30 bit pids.
The pid_mask will start out with 256 entries for the first 8 MSB bits.
This will cost 1K for 32 bit architectures and 2K for 64 bit. Each of
these will have a 256 array to store the next 8 bits of the pid (another
1 or 2K). These will hold an 2K byte bitmask (which will cover the LSB
14 bits or 16384 pids).
When the trace_pid_list is allocated, it will have the 1/2K upper bits
allocated, and then it will allocate a cache for the next upper chunks and
the lower chunks (default 6 of each). Then when a bit is "set", these
chunks will be pulled from the free list and added to the array. If the
free list gets down to a lever (default 2), it will trigger an irqwork
that will refill the cache back up.
On clearing a bit, if the clear causes the bitmask to be zero, that chunk
will then be placed back into the free cache for later use, keeping the
need to allocate more down to a minimum.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Instead of having the logic that does trace_pid_list open coded, wrap it in
abstract functions. This will allow a rewrite of the logic that implements
the trace_pid_list without affecting the users.
Note, this causes a change in behavior. Every time a pid is written into
the set_*_pid file, it creates a new list and uses RCU to update it. If
pid_max is lowered, but there was a pid currently in the list that was
higher than pid_max, those pids will now be removed on updating the list.
The old behavior kept that from happening.
The rewrite of the pid_list logic will no longer depend on pid_max,
and will return the old behavior.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Daniel Borkmann says:
====================
bpf-next 2021-10-02
We've added 85 non-merge commits during the last 15 day(s) which contain
a total of 132 files changed, 13779 insertions(+), 6724 deletions(-).
The main changes are:
1) Massive update on test_bpf.ko coverage for JITs as preparatory work for
an upcoming MIPS eBPF JIT, from Johan Almbladh.
2) Add a batched interface for RX buffer allocation in AF_XDP buffer pool,
with driver support for i40e and ice from Magnus Karlsson.
3) Add legacy uprobe support to libbpf to complement recently merged legacy
kprobe support, from Andrii Nakryiko.
4) Add bpf_trace_vprintk() as variadic printk helper, from Dave Marchevsky.
5) Support saving the register state in verifier when spilling <8byte bounded
scalar to the stack, from Martin Lau.
6) Add libbpf opt-in for stricter BPF program section name handling as part
of libbpf 1.0 effort, from Andrii Nakryiko.
7) Add a document to help clarifying BPF licensing, from Alexei Starovoitov.
8) Fix skel_internal.h to propagate errno if the loader indicates an internal
error, from Kumar Kartikeya Dwivedi.
9) Fix build warnings with -Wcast-function-type so that the option can later
be enabled by default for the kernel, from Kees Cook.
10) Fix libbpf to ignore STT_SECTION symbols in legacy map definitions as it
otherwise errors out when encountering them, from Toke Høiland-Jørgensen.
11) Teach libbpf to recognize specialized maps (such as for perf RB) and
internally remove BTF type IDs when creating them, from Hengqi Chen.
12) Various fixes and improvements to BPF selftests.
====================
Link: https://lore.kernel.org/r/20211002001327.15169-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
ftrace shows "[unknown/kretprobe'd]" indicator all addresses in the
kretprobe_trampoline, but the modified address by kretprobe should
be only kretprobe_trampoline+0.
Link: https://lkml.kernel.org/r/163163056044.489837.794883849706638013.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Tested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Since now there is kretprobe_trampoline_addr() for referring the
address of kretprobe trampoline code, we don't need to access
kretprobe_trampoline directly.
Make it harder to refer by renaming it to __kretprobe_trampoline().
Link: https://lkml.kernel.org/r/163163045446.489837.14510577516938803097.stgit@devnote2
Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Use the 'bool' type instead of 'int' for the functions which
returns a boolean value, because this makes clear that those
functions don't return any error code.
Link: https://lkml.kernel.org/r/163163041649.489837.17311187321419747536.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Colin Ian King