Pointer buf is being assigned a value that is not being read, buf is being
re-assigned in the next starement. The assignment is redundant and can be
removed.
Cleans up clang scan build warning:
kernel/relay.c:443:8: warning: Although the value stored to 'buf' is
used in the enclosing expression, the value is never actually read
from 'buf' [deadcode.DeadStores]
Link: https://lkml.kernel.org/r/20220508212152.58753-1-colin.i.king@gmail.com
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Kalle Valo <kvalo@codeaurora.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
At the end of get_last_crashkernel(), the judgement of ck_cmdline is
obviously unnecessary and causes redundance, let's clean it up.
Link: https://lkml.kernel.org/r/20220506104116.259323-1-sensor1010@163.com
Signed-off-by: lizhe <sensor1010@163.com>
Acked-by: Baoquan He <bhe@redhat.com>
Acked-by: Philipp Rudo <prudo@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
If getdelays runs in a non-init network namespace, it will fail in getting
delayacct stats even if it has privilege of root user, which seems to be
not very reasonable. We can simply reproduce this by executing commands:
unshare -n
getdelays -d -p <pid>
I don't think net namespace should be an obstacle to the normal execution
of getdelay function. So let's make it available from all net namespaces.
Link: https://lkml.kernel.org/r/20220412071946.2532318-1-xu.xin16@zte.com.cn
Signed-off-by: xu xin <xu.xin16@zte.com.cn>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Yang Yang <yang.yang29@zte.com.cn>
Cc: "Dr. Thomas Orgis" <thomas.orgis@uni-hamburg.de>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Ismael Luceno <ismael@iodev.co.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The task exit struct needs some crucial information to be able to provide
an enhanced version of process and thread accounting. This change
provides:
1. ac_tgid in additon to ac_pid
2. thread group execution walltime in ac_tgetime
3. flag AGROUP in ac_flag to indicate the last task
in a thread group / process
4. device ID and inode of task's /proc/self/exe in
ac_exe_dev and ac_exe_inode
5. tools/accounting/procacct as demonstrator
When a task exits, taskstats are reported to userspace including the
task's pid and ppid, but without the id of the thread group this task is
part of. Without the tgid, the stats of single tasks cannot be correlated
to each other as a thread group (process).
The taskstats documentation suggests that on process exit a data set
consisting of accumulated stats for the whole group is produced. But such
an additional set of stats is only produced for actually multithreaded
processes, not groups that had only one thread, and also those stats only
contain data about delay accounting and not the more basic information
about CPU and memory resource usage. Adding the AGROUP flag to be set
when the last task of a group exited enables determination of process end
also for single-threaded processes.
My applicaton basically does enhanced process accounting with summed
cputime, biggest maxrss, tasks per process. The data is not available
with the traditional BSD process accounting (which is not designed to be
extensible) and the taskstats interface allows more efficient on-the-fly
grouping and summing of the stats, anyway, without intermediate disk
writes.
Furthermore, I do carry statistics on which exact program binary is used
how often with associated resources, getting a picture on how important
which parts of a collection of installed scientific software in different
versions are, and how well they put load on the machine. This is enabled
by providing information on /proc/self/exe for each task. I assume the
two 64-bit fields for device ID and inode are more appropriate than the
possibly large resolved path to keep the data volume down.
Add the tgid to the stats to complete task identification, the flag AGROUP
to mark the last task of a group, the group wallclock time, and
inode-based identification of the associated executable file.
Add tools/accounting/procacct.c as a simplified fork of getdelays.c to
demonstrate process and thread accounting.
[thomas.orgis@uni-hamburg.de: fix version number in comment]
Link: https://lkml.kernel.org/r/20220405003601.7a5f6008@plasteblaster
Link: https://lkml.kernel.org/r/20220331004106.64e5616b@plasteblaster
Signed-off-by: Dr. Thomas Orgis <thomas.orgis@uni-hamburg.de>
Reviewed-by: Ismael Luceno <ismael@iodev.co.uk>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: xu xin <xu.xin16@zte.com.cn>
Cc: Yang Yang <yang.yang29@zte.com.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Get rid of redundant assignments which end up in values not being read
either because they are overwritten or the function ends.
Reported by clang-tidy [deadcode.DeadStores]
Link: https://lkml.kernel.org/r/20220326180948.192154-1-michalorzel.eng@gmail.com
Signed-off-by: Michal Orzel <michalorzel.eng@gmail.com>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Michal Orzel <michalorzel.eng@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Patch series "ptrace: do some cleanup".
This patch (of 3):
PTRACE_SINGLESTEP is always defined as 9 in include/uapi/linux/ptrace.h,
remove redudant check of #ifdef PTRACE_SINGLESTEP.
Link: https://lkml.kernel.org/r/1649240981-11024-2-git-send-email-yangtiezhu@loongson.cn
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
As in "kernel/panic.c: remove CONFIG_PANIC_ON_OOPS_VALUE indirection",
use the IS_ENABLED() helper rather than having a hidden config option.
Link: https://lkml.kernel.org/r/20220321121301.1389693-1-linux@rasmusvillemoes.dk
Signed-off-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
and netfilter.
Current release - new code bugs:
- bridge: switchdev: check br_vlan_group() return value
- use this_cpu_inc() to increment net->core_stats, fix preempt-rt
Previous releases - regressions:
- eth: stmmac: fix write to sgmii_adapter_base
Previous releases - always broken:
- netfilter: nf_conntrack_tcp: re-init for syn packets only,
resolving issues with TCP fastopen
- tcp: md5: fix incorrect tcp_header_len for incoming connections
- tcp: fix F-RTO may not work correctly when receiving DSACK
- tcp: ensure use of most recently sent skb when filling rate samples
- tcp: fix potential xmit stalls caused by TCP_NOTSENT_LOWAT
- virtio_net: fix wrong buf address calculation when using xdp
- xsk: fix forwarding when combining copy mode with busy poll
- xsk: fix possible crash when multiple sockets are created
- bpf: lwt: fix crash when using bpf_skb_set_tunnel_key() from
bpf_xmit lwt hook
- sctp: null-check asoc strreset_chunk in sctp_generate_reconf_event
- wireguard: device: check for metadata_dst with skb_valid_dst()
- netfilter: update ip6_route_me_harder to consider L3 domain
- gre: make o_seqno start from 0 in native mode
- gre: switch o_seqno to atomic to prevent races in collect_md mode
Misc:
- add Eric Dumazet to networking maintainers
- dt: dsa: realtek: remove realtek,rtl8367s string
- netfilter: flowtable: Remove the empty file
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
-----BEGIN PGP SIGNATURE-----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=XOSt
-----END PGP SIGNATURE-----
Merge tag 'net-5.18-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Jakub Kicinski:
"Including fixes from bluetooth, bpf and netfilter.
Current release - new code bugs:
- bridge: switchdev: check br_vlan_group() return value
- use this_cpu_inc() to increment net->core_stats, fix preempt-rt
Previous releases - regressions:
- eth: stmmac: fix write to sgmii_adapter_base
Previous releases - always broken:
- netfilter: nf_conntrack_tcp: re-init for syn packets only,
resolving issues with TCP fastopen
- tcp: md5: fix incorrect tcp_header_len for incoming connections
- tcp: fix F-RTO may not work correctly when receiving DSACK
- tcp: ensure use of most recently sent skb when filling rate samples
- tcp: fix potential xmit stalls caused by TCP_NOTSENT_LOWAT
- virtio_net: fix wrong buf address calculation when using xdp
- xsk: fix forwarding when combining copy mode with busy poll
- xsk: fix possible crash when multiple sockets are created
- bpf: lwt: fix crash when using bpf_skb_set_tunnel_key() from
bpf_xmit lwt hook
- sctp: null-check asoc strreset_chunk in sctp_generate_reconf_event
- wireguard: device: check for metadata_dst with skb_valid_dst()
- netfilter: update ip6_route_me_harder to consider L3 domain
- gre: make o_seqno start from 0 in native mode
- gre: switch o_seqno to atomic to prevent races in collect_md mode
Misc:
- add Eric Dumazet to networking maintainers
- dt: dsa: realtek: remove realtek,rtl8367s string
- netfilter: flowtable: Remove the empty file"
* tag 'net-5.18-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (65 commits)
tcp: fix F-RTO may not work correctly when receiving DSACK
Revert "ibmvnic: Add ethtool private flag for driver-defined queue limits"
net: enetc: allow tc-etf offload even with NETIF_F_CSUM_MASK
ixgbe: ensure IPsec VF<->PF compatibility
MAINTAINERS: Update BNXT entry with firmware files
netfilter: nft_socket: only do sk lookups when indev is available
net: fec: add missing of_node_put() in fec_enet_init_stop_mode()
bnx2x: fix napi API usage sequence
tls: Skip tls_append_frag on zero copy size
Add Eric Dumazet to networking maintainers
netfilter: conntrack: fix udp offload timeout sysctl
netfilter: nf_conntrack_tcp: re-init for syn packets only
net: dsa: lantiq_gswip: Don't set GSWIP_MII_CFG_RMII_CLK
net: Use this_cpu_inc() to increment net->core_stats
Bluetooth: hci_sync: Cleanup hci_conn if it cannot be aborted
Bluetooth: hci_event: Fix creating hci_conn object on error status
Bluetooth: hci_event: Fix checking for invalid handle on error status
ice: fix use-after-free when deinitializing mailbox snapshot
ice: wait 5 s for EMP reset after firmware flash
ice: Protect vf_state check by cfg_lock in ice_vc_process_vf_msg()
...
Daniel Borkmann says:
====================
pull-request: bpf 2022-04-27
We've added 5 non-merge commits during the last 20 day(s) which contain
a total of 6 files changed, 34 insertions(+), 12 deletions(-).
The main changes are:
1) Fix xsk sockets when rx and tx are separately bound to the same umem, also
fix xsk copy mode combined with busy poll, from Maciej Fijalkowski.
2) Fix BPF tunnel/collect_md helpers with bpf_xmit lwt hook usage which triggered
a crash due to invalid metadata_dst access, from Eyal Birger.
3) Fix release of page pool in XDP live packet mode, from Toke Høiland-Jørgensen.
4) Fix potential NULL pointer dereference in kretprobes, from Adam Zabrocki.
(Masami & Steven preferred this small fix to be routed via bpf tree given it's
follow-up fix to Masami's rethook work that went via bpf earlier, too.)
* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
xsk: Fix possible crash when multiple sockets are created
kprobes: Fix KRETPROBES when CONFIG_KRETPROBE_ON_RETHOOK is set
bpf, lwt: Fix crash when using bpf_skb_set_tunnel_key() from bpf_xmit lwt hook
bpf: Fix release of page_pool in BPF_PROG_RUN in test runner
xsk: Fix l2fwd for copy mode + busy poll combo
====================
Link: https://lore.kernel.org/r/20220427212748.9576-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
The recent kernel change in 73f9b911fa ("kprobes: Use rethook for kretprobe
if possible"), introduced a potential NULL pointer dereference bug in the
KRETPROBE mechanism. The official Kprobes documentation defines that "Any or
all handlers can be NULL". Unfortunately, there is a missing return handler
verification to fulfill these requirements and can result in a NULL pointer
dereference bug.
This patch adds such verification in kretprobe_rethook_handler() function.
Fixes: 73f9b911fa ("kprobes: Use rethook for kretprobe if possible")
Signed-off-by: Adam Zabrocki <pi3@pi3.com.pl>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Naveen N. Rao <naveen.n.rao@linux.ibm.com>
Cc: Anil S. Keshavamurthy <anil.s.keshavamurthy@intel.com>
Link: https://lore.kernel.org/bpf/20220422164027.GA7862@pi3.com.pl
-----BEGIN PGP SIGNATURE-----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=S7Ux
-----END PGP SIGNATURE-----
Merge tag 'sched_urgent_for_v5.18_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fix from Borislav Petkov:
- Fix a corner case when calculating sched runqueue variables
That fix also removes a check for a zero divisor in the code, without
mentioning it. Vincent clarified that it's ok after I whined about it:
https://lore.kernel.org/all/CAKfTPtD2QEyZ6ADd5WrwETMOX0XOwJGnVddt7VHgfURdqgOS-Q@mail.gmail.com/
* tag 'sched_urgent_for_v5.18_rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/pelt: Fix attach_entity_load_avg() corner case
vm_insert_page()'s failure is not an unexpected condition, so don't do
WARN_ONCE() in such a case.
Instead, print a kernel message and just return an error code.
This flaw has been reported under an OOM condition by sysbot [1].
The message is mainly for the benefit of the test log, in this case the
fuzzer's log so that humans inspecting the log can figure out what was
going on. KCOV is a testing tool, so I think being a little more chatty
when KCOV unexpectedly is about to fail will save someone debugging
time.
We don't want the WARN, because it's not a kernel bug that syzbot should
report, and failure can happen if the fuzzer tries hard enough (as
above).
Link: https://lkml.kernel.org/r/Ylkr2xrVbhQYwNLf@elver.google.com [1]
Link: https://lkml.kernel.org/r/20220401182512.249282-1-nogikh@google.com
Fixes: b3d7fe86fb ("kcov: properly handle subsequent mmap calls"),
Signed-off-by: Aleksandr Nogikh <nogikh@google.com>
Acked-by: Marco Elver <elver@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Taras Madan <tarasmadan@google.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This problem can be reproduced with CONFIG_PERF_USE_VMALLOC enabled on
both x86_64 and aarch64 arch when using sysdig -B(using ebpf)[1].
sysdig -B works fine after rebuilding the kernel with
CONFIG_PERF_USE_VMALLOC disabled.
I tracked it down to the if condition event->rb->nr_pages != nr_pages
in perf_mmap is true when CONFIG_PERF_USE_VMALLOC is enabled where
event->rb->nr_pages = 1 and nr_pages = 2048 resulting perf_mmap to
return -EINVAL. This is because when CONFIG_PERF_USE_VMALLOC is
enabled, rb->nr_pages is always equal to 1.
Arch with CONFIG_PERF_USE_VMALLOC enabled by default:
arc/arm/csky/mips/sh/sparc/xtensa
Arch with CONFIG_PERF_USE_VMALLOC disabled by default:
x86_64/aarch64/...
Fix this problem by using data_page_nr()
[1] https://github.com/draios/sysdig
Fixes: 906010b213 ("perf_event: Provide vmalloc() based mmap() backing")
Signed-off-by: Zhipeng Xie <xiezhipeng1@huawei.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20220209145417.6495-1-xiezhipeng1@huawei.com
The warning in cfs_rq_is_decayed() triggered:
SCHED_WARN_ON(cfs_rq->avg.load_avg ||
cfs_rq->avg.util_avg ||
cfs_rq->avg.runnable_avg)
There exists a corner case in attach_entity_load_avg() which will
cause load_sum to be zero while load_avg will not be.
Consider se_weight is 88761 as per the sched_prio_to_weight[] table.
Further assume the get_pelt_divider() is 47742, this gives:
se->avg.load_avg is 1.
However, calculating load_sum:
se->avg.load_sum = div_u64(se->avg.load_avg * se->avg.load_sum, se_weight(se));
se->avg.load_sum = 1*47742/88761 = 0.
Then enqueue_load_avg() adds this to the cfs_rq totals:
cfs_rq->avg.load_avg += se->avg.load_avg;
cfs_rq->avg.load_sum += se_weight(se) * se->avg.load_sum;
Resulting in load_avg being 1 with load_sum is 0, which will trigger
the WARN.
Fixes: f207934fb7 ("sched/fair: Align PELT windows between cfs_rq and its se")
Signed-off-by: kuyo chang <kuyo.chang@mediatek.com>
[peterz: massage changelog]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Link: https://lkml.kernel.org/r/20220414090229.342-1-kuyo.chang@mediatek.com
- Fix the warning condition in __run_timers() which does not take into
account, that a CPU base (especially the deferrable base) has never a
timer armed on it and therefore the next_expiry value can become stale.
- Replace a WARN_ON() in the NOHZ code with a WARN_ON_ONCE() to prevent
endless spam in dmesg.
- Remove the double star from a comment which is not meant to be in
kernel-doc format.
-----BEGIN PGP SIGNATURE-----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=SffK
-----END PGP SIGNATURE-----
Merge tag 'timers-urgent-2022-04-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fixes from Thomas Gleixner:
"A small set of fixes for the timers core:
- Fix the warning condition in __run_timers() which does not take
into account that a CPU base (especially the deferrable base) never
has a timer armed on it and therefore the next_expiry value can
become stale.
- Replace a WARN_ON() in the NOHZ code with a WARN_ON_ONCE() to
prevent endless spam in dmesg.
- Remove the double star from a comment which is not meant to be in
kernel-doc format"
* tag 'timers-urgent-2022-04-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
tick/sched: Fix non-kernel-doc comment
tick/nohz: Use WARN_ON_ONCE() to prevent console saturation
timers: Fix warning condition in __run_timers()
- Make the warning condition in flush_smp_call_function_queue() correct,
which checks a just emptied list head for being empty instead of
validating that there was no pending entry on the offlined CPU at all.
- The @cpu member of struct cpuhp_cpu_state is initialized when the CPU
hotplug thread for the upcoming CPU is created. That's too late because
the creation of the thread can fail and then the following rollback
operates on CPU0. Get rid of the CPU member and hand the CPU number to
the involved functions directly.
-----BEGIN PGP SIGNATURE-----
iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAmJb4skTHHRnbHhAbGlu
dXRyb25peC5kZQAKCRCmGPVMDXSYoUYaD/9SWzwEqwKICAhWWSMtRg6cvtVTAKGL
xWXNb5ZxLA8MdG9CYu7WaUF7mU3E8o7kF/dItvkdj0/9mg/IqcVnP1CEOfp0ioHc
1cbAZShORfFlOowO1WR9Xe3MSZB2mXPHsjh3FWPeGTDxnSByMDXROMFyotxji+7q
g1ZsyVbq3+hSVTOhnhpxrh8MS3qcCAsgYtHKRnPjOE/tqbNXSmbhmeuN7QBKLVp6
AD6DaWj8jGtZ8yzbpm0Ve3ZsjH+1SdZAzm4yhh3FHMKsSOwB8yuNwq1oNbbEjxWu
mTg+LCBBMGYybSTa9sUpDG5Xfc3/dyWnzkGnmp7M8bfElrI3x4d+sMdVhfFRjEXB
xlXmNqRoExgZwifyoEJbmSbG2SgLiWqyLqgpUvLS/yHud6IurFbu36TrByYRMMsG
CyaiLMdWIlBibo+xGkVgnLyc2io98KeoLJoc35HM7VYyn9oNI4hUU9OJDIkG5D2i
lyS+qMTFInFSOm7L5u/SUTYe4I0sXYJ6uEXxhR/Gi3ITXb7aLOJyxhNtq//u1dmg
6vZHgs8HZWylG3LxVn1QERWotVlPuNPRilsUGCVMsCHjOFnoPy+eM3ANtR2x/uaE
XpQ58jnhkhPXZfmnsjDEILkWB67J0/9FujbcPvixH8SRvUgBB7xRRbuo9zXPchhw
VDKy1BCIcZ93gA==
=XNLP
-----END PGP SIGNATURE-----
Merge tag 'smp-urgent-2022-04-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull SMP fixes from Thomas Gleixner:
"Two fixes for the SMP core:
- Make the warning condition in flush_smp_call_function_queue()
correct, which checked a just emptied list head for being empty
instead of validating that there was no pending entry on the
offlined CPU at all.
- The @cpu member of struct cpuhp_cpu_state is initialized when the
CPU hotplug thread for the upcoming CPU is created. That's too late
because the creation of the thread can fail and then the following
rollback operates on CPU0. Get rid of the CPU member and hand the
CPU number to the involved functions directly"
* tag 'smp-urgent-2022-04-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
cpu/hotplug: Remove the 'cpu' member of cpuhp_cpu_state
smp: Fix offline cpu check in flush_smp_call_function_queue()
account that there can be an imbalance between present and possible CPUs,
which causes already assigned bits to be overwritten.
-----BEGIN PGP SIGNATURE-----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=wSdp
-----END PGP SIGNATURE-----
Merge tag 'irq-urgent-2022-04-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fix from Thomas Gleixner:
"A single fix for the interrupt affinity spreading logic to take into
account that there can be an imbalance between present and possible
CPUs, which causes already assigned bits to be overwritten"
* tag 'irq-urgent-2022-04-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
genirq/affinity: Consider that CPUs on nodes can be unbalanced
On PREEMPT_RT kernel and KASAN is enabled. the kasan_record_aux_stack()
may call alloc_pages(), and the rt-spinlock will be acquired, if currently
in atomic context, will trigger warning:
BUG: sleeping function called from invalid context at kernel/locking/spinlock_rt.c:46
in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 239, name: bootlogd
Preemption disabled at:
[<ffffffffbab1a531>] rt_mutex_slowunlock+0xa1/0x4e0
CPU: 3 PID: 239 Comm: bootlogd Tainted: G W 5.17.1-rt17-yocto-preempt-rt+ #105
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.15.0-0-g2dd4b9b3f840-prebuilt.qemu.org 04/01/2014
Call Trace:
__might_resched.cold+0x13b/0x173
rt_spin_lock+0x5b/0xf0
get_page_from_freelist+0x20c/0x1610
__alloc_pages+0x25e/0x5e0
__stack_depot_save+0x3c0/0x4a0
kasan_save_stack+0x3a/0x50
__kasan_record_aux_stack+0xb6/0xc0
kasan_record_aux_stack+0xe/0x10
irq_work_queue_on+0x6a/0x1c0
pull_rt_task+0x631/0x6b0
do_balance_callbacks+0x56/0x80
__balance_callbacks+0x63/0x90
rt_mutex_setprio+0x349/0x880
rt_mutex_slowunlock+0x22a/0x4e0
rt_spin_unlock+0x49/0x80
uart_write+0x186/0x2b0
do_output_char+0x2e9/0x3a0
n_tty_write+0x306/0x800
file_tty_write.isra.0+0x2af/0x450
tty_write+0x22/0x30
new_sync_write+0x27c/0x3a0
vfs_write+0x3f7/0x5d0
ksys_write+0xd9/0x180
__x64_sys_write+0x43/0x50
do_syscall_64+0x44/0x90
entry_SYSCALL_64_after_hwframe+0x44/0xae
Fix it by using kasan_record_aux_stack_noalloc() to avoid the call to
alloc_pages().
Link: https://lkml.kernel.org/r/20220402142555.2699582-1-qiang1.zhang@intel.com
Signed-off-by: Zqiang <qiang1.zhang@intel.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When we looked into FIO performance with swiotlb enabled in VM, we found
swiotlb_bounce() is always called one more time than expected for each DMA
read request.
It turns out that the bounce buffer is copied to original DMA buffer twice
after the completion of a DMA request (one is done by in
dma_direct_sync_single_for_cpu(), the other by swiotlb_tbl_unmap_single()).
But the content in bounce buffer actually doesn't change between the two
rounds of copy. So, one round of copy is redundant.
Pass DMA_ATTR_SKIP_CPU_SYNC flag to swiotlb_tbl_unmap_single() to
skip the memory copy in it.
This fix increases FIO 64KB sequential read throughput in a guest with
swiotlb=force by 5.6%.
Fixes: 55897af630 ("dma-direct: merge swiotlb_dma_ops into the dma_direct code")
Reported-by: Wang Zhaoyang1 <zhaoyang1.wang@intel.com>
Reported-by: Gao Liang <liang.gao@intel.com>
Signed-off-by: Chao Gao <chao.gao@intel.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Currently the setting of the 'cpu' member of struct cpuhp_cpu_state in
cpuhp_create() is too late as it is used earlier in _cpu_up().
If kzalloc_node() in __smpboot_create_thread() fails then the rollback will
be done with st->cpu==0 causing CPU0 to be erroneously set to be dying,
causing the scheduler to get mightily confused and throw its toys out of
the pram.
However the cpu number is actually available directly, so simply remove
the 'cpu' member and avoid the problem in the first place.
Fixes: 2ea46c6fc9 ("cpumask/hotplug: Fix cpu_dying() state tracking")
Signed-off-by: Steven Price <steven.price@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20220411152233.474129-2-steven.price@arm.com
The check in flush_smp_call_function_queue() for callbacks that are sent
to offline CPUs currently checks whether the queue is empty.
However, flush_smp_call_function_queue() has just deleted all the
callbacks from the queue and moved all the entries into a local list.
This checks would only be positive if some callbacks were added in the
short time after llist_del_all() was called. This does not seem to be
the intention of this check.
Change the check to look at the local list to which the entries were
moved instead of the queue from which all the callbacks were just
removed.
Fixes: 8d056c48e4 ("CPU hotplug, smp: flush any pending IPI callbacks before CPU offline")
Signed-off-by: Nadav Amit <namit@vmware.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20220319072015.1495036-1-namit@vmware.com
If CPUs on a node are offline at boot time, the number of nodes is
different when building affinity masks for present cpus and when building
affinity masks for possible cpus. This causes the following problem:
In the case that the number of vectors is less than the number of nodes
there are cases where bits of masks for present cpus are overwritten when
building masks for possible cpus.
Fix this by excluding CPUs, which are not part of the current build mask
(present/possible).
[ tglx: Massaged changelog and added comment ]
Fixes: b825921990 ("genirq/affinity: Spread IRQs to all available NUMA nodes")
Signed-off-by: Rei Yamamoto <yamamoto.rei@jp.fujitsu.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20220331003309.10891-1-yamamoto.rei@jp.fujitsu.com
- A couple of fixes to event encoding on Sapphire Rapids
- Pass event caps of inherited events so that perf doesn't fail wrongly at fork()
- Add support for a new Raptor Lake CPU
-----BEGIN PGP SIGNATURE-----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=ba3V
-----END PGP SIGNATURE-----
Merge tag 'perf_urgent_for_v5.18_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Borislav Petkov:
- A couple of fixes to cgroup-related handling of perf events
- A couple of fixes to event encoding on Sapphire Rapids
- Pass event caps of inherited events so that perf doesn't fail wrongly
at fork()
- Add support for a new Raptor Lake CPU
* tag 'perf_urgent_for_v5.18_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/core: Always set cpuctx cgrp when enable cgroup event
perf/core: Fix perf_cgroup_switch()
perf/core: Use perf_cgroup_info->active to check if cgroup is active
perf/core: Don't pass task around when ctx sched in
perf/x86/intel: Update the FRONTEND MSR mask on Sapphire Rapids
perf/x86/intel: Don't extend the pseudo-encoding to GP counters
perf/core: Inherit event_caps
perf/x86/uncore: Add Raptor Lake uncore support
perf/x86/msr: Add Raptor Lake CPU support
perf/x86/cstate: Add Raptor Lake support
perf/x86: Add Intel Raptor Lake support
the local_lock_* macros back to inline functions
- A couple of fixes to static call insn patching
-----BEGIN PGP SIGNATURE-----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=hSOc
-----END PGP SIGNATURE-----
Merge tag 'locking_urgent_for_v5.18_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking fixes from Borislav Petkov:
- Allow the compiler to optimize away unused percpu accesses and change
the local_lock_* macros back to inline functions
- A couple of fixes to static call insn patching
* tag 'locking_urgent_for_v5.18_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
Revert "mm/page_alloc: mark pagesets as __maybe_unused"
Revert "locking/local_lock: Make the empty local_lock_*() function a macro."
x86/percpu: Remove volatile from arch_raw_cpu_ptr().
static_call: Remove __DEFINE_STATIC_CALL macro
static_call: Properly initialise DEFINE_STATIC_CALL_RET0()
static_call: Don't make __static_call_return0 static
x86,static_call: Fix __static_call_return0 for i386
- Two fixes for the new forceidle balancer
-----BEGIN PGP SIGNATURE-----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=elMK
-----END PGP SIGNATURE-----
Merge tag 'sched_urgent_for_v5.18_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Borislav Petkov:
- Use the correct static key checking primitive on the IRQ exit path
- Two fixes for the new forceidle balancer
* tag 'sched_urgent_for_v5.18_rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
entry: Fix compile error in dynamic_irqentry_exit_cond_resched()
sched: Teach the forced-newidle balancer about CPU affinity limitation.
sched/core: Fix forceidle balancing
Fixes the following W=1 kernel build warning:
kernel/time/tick-sched.c:1563: warning: This comment starts with '/**',
but isn't a kernel-doc comment.
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20220214084739.63228-1-jiapeng.chong@linux.alibaba.com
While running some testing on code that happened to allow the variable
tick_nohz_full_running to get set but with no "possible" NOHZ cores to
back up that setting, this warning triggered:
if (unlikely(tick_do_timer_cpu == TICK_DO_TIMER_NONE))
WARN_ON(tick_nohz_full_running);
The console was overwhemled with an endless stream of one WARN per tick
per core and there was no way to even see what was going on w/o using a
serial console to capture it and then trace it back to this.
Change it to WARN_ON_ONCE().
Fixes: 08ae95f4fd ("nohz_full: Allow the boot CPU to be nohz_full")
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20211206145950.10927-3-paul.gortmaker@windriver.com
When the timer base is empty, base::next_expiry is set to base::clk +
NEXT_TIMER_MAX_DELTA and base::next_expiry_recalc is false. When no timer
is queued until jiffies reaches base::next_expiry value, the warning for
not finding any expired timer and base::next_expiry_recalc is false in
__run_timers() triggers.
To prevent triggering the warning in this valid scenario
base::timers_pending needs to be added to the warning condition.
Fixes: 31cd0e119d ("timers: Recalculate next timer interrupt only when necessary")
Reported-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20220405191732.7438-3-anna-maria@linutronix.de
Alexei Starovoitov says:
====================
pull-request: bpf 2022-04-06
We've added 8 non-merge commits during the last 8 day(s) which contain
a total of 9 files changed, 139 insertions(+), 36 deletions(-).
The main changes are:
1) rethook related fixes, from Jiri and Masami.
2) Fix the case when tracing bpf prog is attached to struct_ops, from Martin.
3) Support dual-stack sockets in bpf_tcp_check_syncookie, from Maxim.
* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
bpf: Adjust bpf_tcp_check_syncookie selftest to test dual-stack sockets
bpf: Support dual-stack sockets in bpf_tcp_check_syncookie
bpf: selftests: Test fentry tracing a struct_ops program
bpf: Resolve to prog->aux->dst_prog->type only for BPF_PROG_TYPE_EXT
rethook: Fix to use WRITE_ONCE() for rethook:: Handler
selftests/bpf: Fix warning comparing pointer to 0
bpf: Fix sparse warnings in kprobe_multi_resolve_syms
bpftool: Explicit errno handling in skeletons
====================
Link: https://lore.kernel.org/r/20220407031245.73026-1-alexei.starovoitov@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When enable a cgroup event, cpuctx->cgrp setting is conditional
on the current task cgrp matching the event's cgroup, so have to
do it for every new event. It brings complexity but no advantage.
To keep it simple, this patch would always set cpuctx->cgrp
when enable the first cgroup event, and reset to NULL when disable
the last cgroup event.
Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220329154523.86438-5-zhouchengming@bytedance.com
There is a race problem that can trigger WARN_ON_ONCE(cpuctx->cgrp)
in perf_cgroup_switch().
CPU1 CPU2
perf_cgroup_sched_out(prev, next)
cgrp1 = perf_cgroup_from_task(prev)
cgrp2 = perf_cgroup_from_task(next)
if (cgrp1 != cgrp2)
perf_cgroup_switch(prev, PERF_CGROUP_SWOUT)
cgroup_migrate_execute()
task->cgroups = ?
perf_cgroup_attach()
task_function_call(task, __perf_cgroup_move)
perf_cgroup_sched_in(prev, next)
cgrp1 = perf_cgroup_from_task(prev)
cgrp2 = perf_cgroup_from_task(next)
if (cgrp1 != cgrp2)
perf_cgroup_switch(next, PERF_CGROUP_SWIN)
__perf_cgroup_move()
perf_cgroup_switch(task, PERF_CGROUP_SWOUT | PERF_CGROUP_SWIN)
The commit a8d757ef07 ("perf events: Fix slow and broken cgroup
context switch code") want to skip perf_cgroup_switch() when the
perf_cgroup of "prev" and "next" are the same.
But task->cgroups can change in concurrent with context_switch()
in cgroup_migrate_execute(). If cgrp1 == cgrp2 in sched_out(),
cpuctx won't do sched_out. Then task->cgroups changed cause
cgrp1 != cgrp2 in sched_in(), cpuctx will do sched_in. So trigger
WARN_ON_ONCE(cpuctx->cgrp).
Even though __perf_cgroup_move() will be synchronized as the context
switch disables the interrupt, context_switch() still can see the
task->cgroups is changing in the middle, since task->cgroups changed
before sending IPI.
So we have to combine perf_cgroup_sched_in() into perf_cgroup_sched_out(),
unified into perf_cgroup_switch(), to fix the incosistency between
perf_cgroup_sched_out() and perf_cgroup_sched_in().
But we can't just compare prev->cgroups with next->cgroups to decide
whether to skip cpuctx sched_out/in since the prev->cgroups is changing
too. For example:
CPU1 CPU2
cgroup_migrate_execute()
prev->cgroups = ?
perf_cgroup_attach()
task_function_call(task, __perf_cgroup_move)
perf_cgroup_switch(task)
cgrp1 = perf_cgroup_from_task(prev)
cgrp2 = perf_cgroup_from_task(next)
if (cgrp1 != cgrp2)
cpuctx sched_out/in ...
task_function_call() will return -ESRCH
In the above example, prev->cgroups changing cause (cgrp1 == cgrp2)
to be true, so skip cpuctx sched_out/in. And later task_function_call()
would return -ESRCH since the prev task isn't running on cpu anymore.
So we would leave perf_events of the old prev->cgroups still sched on
the CPU, which is wrong.
The solution is that we should use cpuctx->cgrp to compare with
the next task's perf_cgroup. Since cpuctx->cgrp can only be changed
on local CPU, and we have irq disabled, we can read cpuctx->cgrp to
compare without holding ctx lock.
Fixes: a8d757ef07 ("perf events: Fix slow and broken cgroup context switch code")
Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220329154523.86438-4-zhouchengming@bytedance.com
Since we use perf_cgroup_set_timestamp() to start cgroup time and
set active to 1, then use update_cgrp_time_from_cpuctx() to stop
cgroup time and set active to 0.
We can use info->active directly to check if cgroup is active.
Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220329154523.86438-3-zhouchengming@bytedance.com
The current code pass task around for ctx_sched_in(), only
to get perf_cgroup of the task, then update the timestamp
of it and its ancestors and set them to active.
But we can use cpuctx->cgrp to get active perf_cgroup and
its ancestors since cpuctx->cgrp has been set before
ctx_sched_in().
This patch remove the task argument in ctx_sched_in()
and cleanup related code.
Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220329154523.86438-2-zhouchengming@bytedance.com
It was reported that some perf event setup can make fork failed on
ARM64. It was the case of a group of mixed hw and sw events and it
failed in perf_event_init_task() due to armpmu_event_init().
The ARM PMU code checks if all the events in a group belong to the
same PMU except for software events. But it didn't set the event_caps
of inherited events and no longer identify them as software events.
Therefore the test failed in a child process.
A simple reproducer is:
$ perf stat -e '{cycles,cs,instructions}' perf bench sched messaging
# Running 'sched/messaging' benchmark:
perf: fork(): Invalid argument
The perf stat was fine but the perf bench failed in fork(). Let's
inherit the event caps from the parent.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20220328200112.457740-1-namhyung@kernel.org
System.map shows that vmlinux contains several instances of
__static_call_return0():
c0004fc0 t __static_call_return0
c0011518 t __static_call_return0
c00d8160 t __static_call_return0
arch_static_call_transform() uses the middle one to check whether we are
setting a call to __static_call_return0 or not:
c0011520 <arch_static_call_transform>:
c0011520: 3d 20 c0 01 lis r9,-16383 <== r9 = 0xc001 << 16
c0011524: 39 29 15 18 addi r9,r9,5400 <== r9 += 0x1518
c0011528: 7c 05 48 00 cmpw r5,r9 <== r9 has value 0xc0011518 here
So if static_call_update() is called with one of the other instances of
__static_call_return0(), arch_static_call_transform() won't recognise it.
In order to work properly, global single instance of __static_call_return0() is required.
Fixes: 3f2a8fc4b1 ("static_call/x86: Add __static_call_return0()")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/30821468a0e7d28251954b578e5051dc09300d04.1647258493.git.christophe.leroy@csgroup.eu
kernel/entry/common.c: In function ‘dynamic_irqentry_exit_cond_resched’:
kernel/entry/common.c:409:14: error: implicit declaration of function ‘static_key_unlikely’; did you mean ‘static_key_enable’? [-Werror=implicit-function-declaration]
409 | if (!static_key_unlikely(&sk_dynamic_irqentry_exit_cond_resched))
| ^~~~~~~~~~~~~~~~~~~
| static_key_enable
static_key_unlikely() should be static_branch_unlikely().
Fixes: 99cf983cc8 ("sched/preempt: Add PREEMPT_DYNAMIC using static keys")
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Link: https://lore.kernel.org/r/20220330084328.1805665-1-svens@linux.ibm.com
try_steal_cookie() looks at task_struct::cpus_mask to decide if the
task could be moved to `this' CPU. It ignores that the task might be in
a migration disabled section while not on the CPU. In this case the task
must not be moved otherwise per-CPU assumption are broken.
Use is_cpu_allowed(), as suggested by Peter Zijlstra, to decide if the a
task can be moved.
Fixes: d2dfa17bc7 ("sched: Trivial forced-newidle balancer")
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/YjNK9El+3fzGmswf@linutronix.de
Steve reported that ChromeOS encounters the forceidle balancer being
ran from rt_mutex_setprio()'s balance_callback() invocation and
explodes.
Now, the forceidle balancer gets queued every time the idle task gets
selected, set_next_task(), which is strictly too often.
rt_mutex_setprio() also uses set_next_task() in the 'change' pattern:
queued = task_on_rq_queued(p); /* p->on_rq == TASK_ON_RQ_QUEUED */
running = task_current(rq, p); /* rq->curr == p */
if (queued)
dequeue_task(...);
if (running)
put_prev_task(...);
/* change task properties */
if (queued)
enqueue_task(...);
if (running)
set_next_task(...);
However, rt_mutex_setprio() will explicitly not run this pattern on
the idle task (since priority boosting the idle task is quite insane).
Most other 'change' pattern users are pidhash based and would also not
apply to idle.
Also, the change pattern doesn't contain a __balance_callback()
invocation and hence we could have an out-of-band balance-callback,
which *should* trigger the WARN in rq_pin_lock() (which guards against
this exact anti-pattern).
So while none of that explains how this happens, it does indicate that
having it in set_next_task() might not be the most robust option.
Instead, explicitly queue the forceidle balancer from pick_next_task()
when it does indeed result in forceidle selection. Having it here,
ensures it can only be triggered under the __schedule() rq->lock
instance, and hence must be ran from that context.
This also happens to clean up the code a little, so win-win.
Fixes: d2dfa17bc7 ("sched: Trivial forced-newidle balancer")
Reported-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: T.J. Alumbaugh <talumbau@chromium.org>
Link: https://lkml.kernel.org/r/20220330160535.GN8939@worktop.programming.kicks-ass.net
- Rename the staging files to give them some meaning.
Just stage1,stag2,etc, does not show what they are for
- Check for NULL from allocation in bootconfig
- Hold event mutex for dyn_event call in user events
- Mark user events to broken (to work on the API)
- Remove eBPF updates from user events
- Remove user events from uapi header to keep it from being installed.
- Move ftrace_graph_is_dead() into inline as it is called from hot paths
and also convert it into a static branch.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCYkmyIBQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qutfAQD90gbUgFMFe2akF5sKhonF5T6mm0+w
BsWqNlBEKBxmfwD+Krfpxql/PKp/gCufcIUUkYC4E6Wl9akf3eO1qQel1Ao=
=ZTn1
-----END PGP SIGNATURE-----
Merge tag 'trace-v5.18-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull more tracing updates from Steven Rostedt:
- Rename the staging files to give them some meaning. Just
stage1,stag2,etc, does not show what they are for
- Check for NULL from allocation in bootconfig
- Hold event mutex for dyn_event call in user events
- Mark user events to broken (to work on the API)
- Remove eBPF updates from user events
- Remove user events from uapi header to keep it from being installed.
- Move ftrace_graph_is_dead() into inline as it is called from hot
paths and also convert it into a static branch.
* tag 'trace-v5.18-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Move user_events.h temporarily out of include/uapi
ftrace: Make ftrace_graph_is_dead() a static branch
tracing: Set user_events to BROKEN
tracing/user_events: Remove eBPF interfaces
tracing/user_events: Hold event_mutex during dyn_event_add
proc: bootconfig: Add null pointer check
tracing: Rename the staging files for trace_events
generalized.
-----BEGIN PGP SIGNATURE-----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=mJKF
-----END PGP SIGNATURE-----
Merge tag 'core-urgent-2022-04-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull RT signal fix from Thomas Gleixner:
"Revert the RT related signal changes. They need to be reworked and
generalized"
* tag 'core-urgent-2022-04-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
Revert "signal, x86: Delay calling signals in atomic on RT enabled kernels"
- fix a regression in dma remap handling vs AMD memory encryption (me)
- finally kill off the legacy PCI DMA API (Christophe JAILLET)
-----BEGIN PGP SIGNATURE-----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=q+vI
-----END PGP SIGNATURE-----
Merge tag 'dma-mapping-5.18-1' of git://git.infradead.org/users/hch/dma-mapping
Pull more dma-mapping updates from Christoph Hellwig:
- fix a regression in dma remap handling vs AMD memory encryption (me)
- finally kill off the legacy PCI DMA API (Christophe JAILLET)
* tag 'dma-mapping-5.18-1' of git://git.infradead.org/users/hch/dma-mapping:
dma-mapping: move pgprot_decrypted out of dma_pgprot
PCI/doc: cleanup references to the legacy PCI DMA API
PCI: Remove the deprecated "pci-dma-compat.h" API
After being merged, user_events become more visible to a wider audience
that have concerns with the current API.
It is too late to fix this for this release, but instead of a full
revert, just mark it as BROKEN (which prevents it from being selected in
make config). Then we can work finding a better API. If that fails,
then it will need to be completely reverted.
To not have the code silently bitrot, still allow building it with
COMPILE_TEST.
And to prevent the uapi header from being installed, then later changed,
and then have an old distro user space see the old version, move the
header file out of the uapi directory.
Surround the include with CONFIG_COMPILE_TEST to the current location,
but when the BROKEN tag is taken off, it will use the uapi directory,
and fail to compile. This is a good way to remind us to move the header
back.
Link: https://lore.kernel.org/all/20220330155835.5e1f6669@gandalf.local.home
Link: https://lkml.kernel.org/r/20220330201755.29319-1-mathieu.desnoyers@efficios.com
Suggested-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
While user_events API is under development and has been marked for broken
to not let the API become fixed, move the header file out of the uapi
directory. This is to prevent it from being installed, then later changed,
and then have an old distro user space update with a new kernel, where
applications see the user_events being available, but the old header is in
place, and then they get compiled incorrectly.
Also, surround the include with CONFIG_COMPILE_TEST to the current
location, but when the BROKEN tag is taken off, it will use the uapi
directory, and fail to compile. This is a good way to remind us to move
the header back.
Link: https://lore.kernel.org/all/20220330155835.5e1f6669@gandalf.local.home
Link: https://lkml.kernel.org/r/20220330201755.29319-1-mathieu.desnoyers@efficios.com
Link: https://lkml.kernel.org/r/20220401143903.188384f3@gandalf.local.home
Suggested-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
ftrace_graph_is_dead() is used on hot paths, it just reads a variable
in memory and is not worth suffering function call constraints.
For instance, at entry of prepare_ftrace_return(), inlining it avoids
saving prepare_ftrace_return() parameters to stack and restoring them
after calling ftrace_graph_is_dead().
While at it using a static branch is even more performant and is
rather well adapted considering that the returned value will almost
never change.
Inline ftrace_graph_is_dead() and replace 'kill_ftrace_graph' bool
by a static branch.
The performance improvement is noticeable.
Link: https://lkml.kernel.org/r/e0411a6a0ed3eafff0ad2bc9cd4b0e202b4617df.1648623570.git.christophe.leroy@csgroup.eu
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>