| Age | Commit message (Collapse) | Author |
|---|
|
Use force_fatal_sig instead of calling do_exit directly. This ensures
the ordinary signal handling path gets invoked, core dumps as
appropriate get created, and for multi-threaded processes all of the
threads are terminated not just a single thread.
When asked Gabriel Krisman Bertazi <krisman@collabora.com> said [1]:
> ebiederm@xmission.com (Eric W. Biederman) asked:
>
> > Why does do_syscal_user_dispatch call do_exit(SIGSEGV) and
> > do_exit(SIGSYS) instead of force_sig(SIGSEGV) and force_sig(SIGSYS)?
> >
> > Looking at the code these cases are not expected to happen, so I would
> > be surprised if userspace depends on any particular behaviour on the
> > failure path so I think we can change this.
>
> Hi Eric,
>
> There is not really a good reason, and the use case that originated the
> feature doesn't rely on it.
>
> Unless I'm missing yet another problem and others correct me, I think
> it makes sense to change it as you described.
>
> > Is using do_exit in this way something you copied from seccomp?
>
> I'm not sure, its been a while, but I think it might be just that. The
> first prototype of SUD was implemented as a seccomp mode.
If at some point it becomes interesting we could relax
"force_fatal_sig(SIGSEGV)" to instead say
"force_sig_fault(SIGSEGV, SEGV_MAPERR, sd->selector)".
I avoid doing that in this patch to avoid making it possible
to catch currently uncatchable signals.
Cc: Gabriel Krisman Bertazi <krisman@collabora.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andy Lutomirski <luto@kernel.org>
[1] https://lkml.kernel.org/r/87mtr6gdvi.fsf@collabora.com
Link: https://lkml.kernel.org/r/20211020174406.17889-14-ebiederm@xmission.com
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
|
|
Add a simple helper force_fatal_sig that causes a signal to be
delivered to a process as if the signal handler was set to SIG_DFL.
Reimplement force_sigsegv based upon this new helper. This fixes
force_sigsegv so that when it forces the default signal handler
to be used the code now forces the signal to be unblocked as well.
Reusing the tested logic in force_sig_info_to_task that was built for
force_sig_seccomp this makes the implementation trivial.
This is interesting both because it makes force_sigsegv simpler and
because there are a couple of buggy places in the kernel that call
do_exit(SIGILL) or do_exit(SIGSYS) because there is no straight
forward way today for those places to simply force the exit of a
process with the chosen signal. Creating force_fatal_sig allows
those places to be implemented with normal signal exits.
Link: https://lkml.kernel.org/r/20211020174406.17889-13-ebiederm@xmission.com
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
|
|
In 2009 Oleg reworked[1] the kernel threads so that it is not
necessary to call do_exit if you are not using kthread_stop(). Remove
the explicit calls of do_exit and complete_and_exit (with a NULL
completion) that were previously necessary.
[1] 63706172f332 ("kthreads: rework kthread_stop()")
Link: https://lkml.kernel.org/r/20211020174406.17889-12-ebiederm@xmission.com
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing comment fixes from Steven Rostedt:
- Some bots have informed me that some of the ftrace functions
kernel-doc has formatting issues.
- Also, fix my snake instinct.
* tag 'trace-v5.15-rc6-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Fix misspelling of "missing"
ftrace: Fix kernel-doc formatting issues
|
|
My snake instinct was on and I wrote "misssing" instead of "missing".
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
|
|
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>
|
|
* for-next/scs:
scs: Release kasan vmalloc poison in scs_free process
|
|
Merge irqchip updates for Linux 5.16 from Marc Zyngier:
- A large cross-arch rework to move irq_enter()/irq_exit() into
the arch code, and removing it from the generic irq code.
Thanks to Mark Rutland for the huge effort!
- A few irqchip drivers are made modular (broadcom, meson), because
that's apparently a thing...
- A new driver for the Microchip External Interrupt Controller
- The irq_cpu_offline()/irq_cpu_online() API is now deprecated and
can only be selected on the Cavium Octeon platform. Once this
platform is removed, the API will be removed at the same time.
- A sprinkle of devm_* helper, as people seem to love that.
- The usual spattering of small fixes and minor improvements.
* tag 'irqchip-5.16': (912 commits)
h8300: Fix linux/irqchip.h include mess
dt-bindings: irqchip: renesas-irqc: Document r8a774e1 bindings
MIPS: irq: Avoid an unused-variable error
genirq: Hide irq_cpu_{on,off}line() behind a deprecated option
irqchip/mips-gic: Get rid of the reliance on irq_cpu_online()
MIPS: loongson64: Drop call to irq_cpu_offline()
irq: remove handle_domain_{irq,nmi}()
irq: remove CONFIG_HANDLE_DOMAIN_IRQ_IRQENTRY
irq: riscv: perform irqentry in entry code
irq: openrisc: perform irqentry in entry code
irq: csky: perform irqentry in entry code
irq: arm64: perform irqentry in entry code
irq: arm: perform irqentry in entry code
irq: add a (temporary) CONFIG_HANDLE_DOMAIN_IRQ_IRQENTRY
irq: nds32: avoid CONFIG_HANDLE_DOMAIN_IRQ
irq: arc: avoid CONFIG_HANDLE_DOMAIN_IRQ
irq: add generic_handle_arch_irq()
irq: unexport handle_irq_desc()
irq: simplify handle_domain_{irq,nmi}()
irq: mips: simplify do_domain_IRQ()
...
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lore.kernel.org/r/20211029083332.3680101-1-maz@kernel.org
|
|
This helper allows us to get the address of a kernel symbol from inside
a BPF_PROG_TYPE_SYSCALL prog (used by gen_loader), so that we can
relocate typeless ksym vars.
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20211028063501.2239335-2-memxor@gmail.com
|
|
This patch adds the kernel-side changes for the implementation of
a bpf bloom filter map.
The bloom filter map supports peek (determining whether an element
is present in the map) and push (adding an element to the map)
operations.These operations are exposed to userspace applications
through the already existing syscalls in the following way:
BPF_MAP_LOOKUP_ELEM -> peek
BPF_MAP_UPDATE_ELEM -> push
The bloom filter map does not have keys, only values. In light of
this, the bloom filter map's API matches that of queue stack maps:
user applications use BPF_MAP_LOOKUP_ELEM/BPF_MAP_UPDATE_ELEM
which correspond internally to bpf_map_peek_elem/bpf_map_push_elem,
and bpf programs must use the bpf_map_peek_elem and bpf_map_push_elem
APIs to query or add an element to the bloom filter map. When the
bloom filter map is created, it must be created with a key_size of 0.
For updates, the user will pass in the element to add to the map
as the value, with a NULL key. For lookups, the user will pass in the
element to query in the map as the value, with a NULL key. In the
verifier layer, this requires us to modify the argument type of
a bloom filter's BPF_FUNC_map_peek_elem call to ARG_PTR_TO_MAP_VALUE;
as well, in the syscall layer, we need to copy over the user value
so that in bpf_map_peek_elem, we know which specific value to query.
A few things to please take note of:
* If there are any concurrent lookups + updates, the user is
responsible for synchronizing this to ensure no false negative lookups
occur.
* The number of hashes to use for the bloom filter is configurable from
userspace. If no number is specified, the default used will be 5 hash
functions. The benchmarks later in this patchset can help compare the
performance of using different number of hashes on different entry
sizes. In general, using more hashes decreases both the false positive
rate and the speed of a lookup.
* Deleting an element in the bloom filter map is not supported.
* The bloom filter map may be used as an inner map.
* The "max_entries" size that is specified at map creation time is used
to approximate a reasonable bitmap size for the bloom filter, and is not
otherwise strictly enforced. If the user wishes to insert more entries
into the bloom filter than "max_entries", they may do so but they should
be aware that this may lead to a higher false positive rate.
Signed-off-by: Joanne Koong <joannekoong@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20211027234504.30744-2-joannekoong@fb.com
|
|
include/net/sock.h
7b50ecfcc6cd ("net: Rename ->stream_memory_read to ->sock_is_readable")
4c1e34c0dbff ("vsock: Enable y2038 safe timeval for timeout")
drivers/net/ethernet/marvell/octeontx2/af/rvu_debugfs.c
0daa55d033b0 ("octeontx2-af: cn10k: debugfs for dumping LMTST map table")
e77bcdd1f639 ("octeontx2-af: Display all enabled PF VF rsrc_alloc entries.")
Adjacent code addition in both cases, keep both.
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Pull networking fixes from Jakub Kicinski:
"Including fixes from WiFi (mac80211), and BPF.
Current release - regressions:
- skb_expand_head: adjust skb->truesize to fix socket memory
accounting
- mptcp: fix corrupt receiver key in MPC + data + checksum
Previous releases - regressions:
- multicast: calculate csum of looped-back and forwarded packets
- cgroup: fix memory leak caused by missing cgroup_bpf_offline
- cfg80211: fix management registrations locking, prevent list
corruption
- cfg80211: correct false positive in bridge/4addr mode check
- tcp_bpf: fix race in the tcp_bpf_send_verdict resulting in reusing
previous verdict
Previous releases - always broken:
- sctp: enhancements for the verification tag, prevent attackers from
killing SCTP sessions
- tipc: fix size validations for the MSG_CRYPTO type
- mac80211: mesh: fix HE operation element length check, prevent out
of bound access
- tls: fix sign of socket errors, prevent positive error codes being
reported from read()/write()
- cfg80211: scan: extend RCU protection in
cfg80211_add_nontrans_list()
- implement ->sock_is_readable() for UDP and AF_UNIX, fix poll() for
sockets in a BPF sockmap
- bpf: fix potential race in tail call compatibility check resulting
in two operations which would make the map incompatible succeeding
- bpf: prevent increasing bpf_jit_limit above max
- bpf: fix error usage of map_fd and fdget() in generic batch update
- phy: ethtool: lock the phy for consistency of results
- prevent infinite while loop in skb_tx_hash() when Tx races with
driver reconfiguring the queue <> traffic class mapping
- usbnet: fixes for bad HW conjured by syzbot
- xen: stop tx queues during live migration, prevent UAF
- net-sysfs: initialize uid and gid before calling
net_ns_get_ownership
- mlxsw: prevent Rx stalls under memory pressure"
* tag 'net-5.15-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (67 commits)
Revert "net: hns3: fix pause config problem after autoneg disabled"
mptcp: fix corrupt receiver key in MPC + data + checksum
riscv, bpf: Fix potential NULL dereference
octeontx2-af: Fix possible null pointer dereference.
octeontx2-af: Display all enabled PF VF rsrc_alloc entries.
octeontx2-af: Check whether ipolicers exists
net: ethernet: microchip: lan743x: Fix skb allocation failure
net/tls: Fix flipped sign in async_wait.err assignment
net/tls: Fix flipped sign in tls_err_abort() calls
net/smc: Correct spelling mistake to TCPF_SYN_RECV
net/smc: Fix smc_link->llc_testlink_time overflow
nfp: bpf: relax prog rejection for mtu check through max_pkt_offset
vmxnet3: do not stop tx queues after netif_device_detach()
r8169: Add device 10ec:8162 to driver r8169
ptp: Document the PTP_CLK_MAGIC ioctl number
usbnet: fix error return code in usbnet_probe()
net: hns3: adjust string spaces of some parameters of tx bd info in debugfs
net: hns3: expand buffer len for some debugfs command
net: hns3: add more string spaces for dumping packets number of queue info in debugfs
net: hns3: fix data endian problem of some functions of debugfs
...
|
|
git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fix from Steven Rostedt:
"Do not WARN when attaching event probe to non-existent event
If the user tries to attach an event probe (eprobe) to an event that
does not exist, it will trigger a warning. There's an error check that
only expects memory issues otherwise it is considered a bug. But
changes in the code to move around the locking made it that it can
error out if the user attempts to attach to an event that does not
exist, returning an -ENODEV. As this path can be caused by user space
putting in a bad value, do not trigger a WARN"
* tag 'trace-v5.15-rc6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Do not warn when connecting eprobe to non existing event
|
|
* irq/irq_cpu_offline:
: .
: Make irq_cpu_{on,off}line() deprecated kernel API, and only
: enable it for some obscure Cavium platform after having
: moved all the other users away from it.
:
: Next step, drop the platform itself.
: .
genirq: Hide irq_cpu_{on,off}line() behind a deprecated option
irqchip/mips-gic: Get rid of the reliance on irq_cpu_online()
MIPS: loongson64: Drop call to irq_cpu_offline()
Signed-off-by: Marc Zyngier <maz@kernel.org>
|
|
* irq/remove-handle-domain-irq-20211026:
: Large rework of the architecture entry code from Mark Rutland.
: From the cover letter:
:
: <quote>
: The handle_domain_{irq,nmi}() functions were oringally intended as a
: convenience, but recent rework to entry code across the kernel tree has
: demonstrated that they cause more pain than they're worth and prevent
: architectures from being able to write robust entry code.
:
: This series reworks the irq code to remove them, handling the necessary
: entry work consistently in entry code (be it architectural or generic).
: </quote>
MIPS: irq: Avoid an unused-variable error
irq: remove handle_domain_{irq,nmi}()
irq: remove CONFIG_HANDLE_DOMAIN_IRQ_IRQENTRY
irq: riscv: perform irqentry in entry code
irq: openrisc: perform irqentry in entry code
irq: csky: perform irqentry in entry code
irq: arm64: perform irqentry in entry code
irq: arm: perform irqentry in entry code
irq: add a (temporary) CONFIG_HANDLE_DOMAIN_IRQ_IRQENTRY
irq: nds32: avoid CONFIG_HANDLE_DOMAIN_IRQ
irq: arc: avoid CONFIG_HANDLE_DOMAIN_IRQ
irq: add generic_handle_arch_irq()
irq: unexport handle_irq_desc()
irq: simplify handle_domain_{irq,nmi}()
irq: mips: simplify do_domain_IRQ()
irq: mips: stop (ab)using handle_domain_irq()
irq: mips: simplify bcm6345_l1_irq_handle()
irq: mips: avoid nested irq_enter()
Signed-off-by: Marc Zyngier <maz@kernel.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: 7491e2c442781 ("tracing: Add a probe that attaches to trace events")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
|
|
Commit 316580b69d0a ("u64_stats: provide u64_stats_t type")
fixed possible load/store tearing on 64bit arches.
For instance the following C code
stats->nsecs += sched_clock() - start;
Could be rightfully implemented like this by a compiler,
confusing concurrent readers a lot:
stats->nsecs += sched_clock();
// arbitrary delay
stats->nsecs -= start;
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211026214133.3114279-4-eric.dumazet@gmail.com
|
|
It seems update_prog_stats() suffers from same issue fixed
in the prior patch:
As it can run while interrupts are enabled, it could
be re-entered and the u64_stats syncp could be mangled.
Fixes: fec56f5890d9 ("bpf: Introduce BPF trampoline")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211026214133.3114279-3-eric.dumazet@gmail.com
|
|
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>
|
|
Clarify argument names and contract for fsnotify_create() and
fsnotify_mkdir() to reflect the anomaly of kernfs, which leaves dentries
negavite after mkdir/create.
Remove the WARN_ON(!inode) in audit code that were added by the Fixes
commit under the wrong assumption that dentries cannot be negative after
mkdir/create.
Fixes: aa93bdc5500c ("fsnotify: use helpers to access data by data_type")
Link: https://lore.kernel.org/linux-fsdevel/87mtp5yz0q.fsf@collabora.com/
Link: https://lore.kernel.org/r/20211025192746.66445-4-krisman@collabora.com
Reviewed-by: Jan Kara <jack@suse.cz>
Reported-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
Signed-off-by: Jan Kara <jack@suse.cz>
|
|
'dma_mem->bitmap' is a bitmap. So use 'bitmap_zalloc()' to simplify code,
improve the semantic and avoid some open-coded arithmetic in allocator
arguments.
Also change the corresponding 'kfree()' into 'bitmap_free()' to keep
consistency.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Christoph Hellwig <hch@lst.de>
|
|
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>
|
|
Daniel Borkmann says:
====================
pull-request: bpf 2021-10-26
We've added 12 non-merge commits during the last 7 day(s) which contain
a total of 23 files changed, 118 insertions(+), 98 deletions(-).
The main changes are:
1) Fix potential race window in BPF tail call compatibility check, from Toke Høiland-Jørgensen.
2) Fix memory leak in cgroup fs due to missing cgroup_bpf_offline(), from Quanyang Wang.
3) Fix file descriptor reference counting in generic_map_update_batch(), from Xu Kuohai.
4) Fix bpf_jit_limit knob to the max supported limit by the arch's JIT, from Lorenz Bauer.
5) Fix BPF sockmap ->poll callbacks for UDP and AF_UNIX sockets, from Cong Wang and Yucong Sun.
6) Fix BPF sockmap concurrency issue in TCP on non-blocking sendmsg calls, from Liu Jian.
7) Fix build failure of INODE_STORAGE and TASK_STORAGE maps on !CONFIG_NET, from Tejun Heo.
* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf:
bpf: Fix potential race in tail call compatibility check
bpf: Move BPF_MAP_TYPE for INODE_STORAGE and TASK_STORAGE outside of CONFIG_NET
selftests/bpf: Use recv_timeout() instead of retries
net: Implement ->sock_is_readable() for UDP and AF_UNIX
skmsg: Extract and reuse sk_msg_is_readable()
net: Rename ->stream_memory_read to ->sock_is_readable
tcp_bpf: Fix one concurrency problem in the tcp_bpf_send_verdict function
cgroup: Fix memory leak caused by missing cgroup_bpf_offline
bpf: Fix error usage of map_fd and fdget() in generic_map_update_batch()
bpf: Prevent increasing bpf_jit_limit above max
bpf: Define bpf_jit_alloc_exec_limit for arm64 JIT
bpf: Define bpf_jit_alloc_exec_limit for riscv JIT
====================
Link: https://lore.kernel.org/r/20211026201920.11296-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
|
|
Since config KPROBES_SANITY_TEST is in lib/Kconfig.debug, it is better to
let test_kprobes.c in lib/, just like other similar tests found in lib/.
Link: https://lkml.kernel.org/r/1635213091-24387-4-git-send-email-yangtiezhu@loongson.cn
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
|
|
Add a test case for stacktrace from kretprobe handler and
nested kretprobe handlers.
This test checks both of stack trace inside kretprobe handler
and stack trace from pt_regs. Those stack trace must include
actual function return address instead of kretprobe trampoline.
The nested kretprobe stacktrace test checks whether the unwinder
can correctly unwind the call frame on the stack which has been
modified by the kretprobe.
Since the stacktrace on kretprobe is correctly fixed only on x86,
this introduces a meta kconfig ARCH_CORRECT_STACKTRACE_ON_KRETPROBE
which tells user that the stacktrace on kretprobe is correct or not.
The test results will be shown like below;
TAP version 14
1..1
# Subtest: kprobes_test
1..6
ok 1 - test_kprobe
ok 2 - test_kprobes
ok 3 - test_kretprobe
ok 4 - test_kretprobes
ok 5 - test_stacktrace_on_kretprobe
ok 6 - test_stacktrace_on_nested_kretprobe
# kprobes_test: pass:6 fail:0 skip:0 total:6
# Totals: pass:6 fail:0 skip:0 total:6
ok 1 - kprobes_test
Link: https://lkml.kernel.org/r/163516211244.604541.18350507860972214415.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
|
|
Lorenzo noticed that the code testing for program type compatibility of
tail call maps is potentially racy in that two threads could encounter a
map with an unset type simultaneously and both return true even though they
are inserting incompatible programs.
The race window is quite small, but artificially enlarging it by adding a
usleep_range() inside the check in bpf_prog_array_compatible() makes it
trivial to trigger from userspace with a program that does, essentially:
map_fd = bpf_create_map(BPF_MAP_TYPE_PROG_ARRAY, 4, 4, 2, 0);
pid = fork();
if (pid) {
key = 0;
value = xdp_fd;
} else {
key = 1;
value = tc_fd;
}
err = bpf_map_update_elem(map_fd, &key, &value, 0);
While the race window is small, it has potentially serious ramifications in
that triggering it would allow a BPF program to tail call to a program of a
different type. So let's get rid of it by protecting the update with a
spinlock. The commit in the Fixes tag is the last commit that touches the
code in question.
v2:
- Use a spinlock instead of an atomic variable and cmpxchg() (Alexei)
v3:
- Put lock and the members it protects into an embedded 'owner' struct (Daniel)
Fixes: 3324b584b6f6 ("ebpf: misc core cleanup")
Reported-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20211026110019.363464-1-toke@redhat.com
|
|
Make valid_state() check if the ->enter callback is present in
suspend_ops (only PM_SUSPEND_TO_IDLE can be valid otherwise) and
make sleep_state_supported() call valid_state() consistently to
validate the states other than PM_SUSPEND_TO_IDLE.
While at it, clean up the comment in valid_state().
No expected functional impact.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
|
|
Commit 8651f97bd951 ("PM / cpuidle: System resume hang fix with
cpuidle") that introduced cpuidle pausing during system suspend
did that to work around a platform firmware issue causing systems
to hang during resume if CPUs were allowed to enter idle states
in the system suspend and resume code paths.
However, pausing cpuidle before the last phase of suspending
devices is the source of an otherwise arbitrary difference between
the suspend-to-idle path and other system suspend variants, so it is
cleaner to do that later, before taking secondary CPUs offline (it
is still safer to take secondary CPUs offline with cpuidle paused,
though).
Modify the code accordingly, but in order to avoid code duplication,
introduce new wrapper functions, pm_sleep_disable_secondary_cpus()
and pm_sleep_enable_secondary_cpus(), to combine cpuidle_pause()
and cpuidle_resume(), respectively, with the handling of secondary
CPUs during system-wide transitions to sleep states.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Ulf Hansson <ulf.hansson@linaro.org>
|
|
It is pointless to pause cpuidle in the suspend-to-idle path,
because it is going to be resumed in the same path later and
pausing it does not serve any particular purpose in that case.
Rework the code to avoid doing that.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Tested-by: Ulf Hansson <ulf.hansson@linaro.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>
|
|
trace_boot_init_histograms misses NULL pointer checks for kstrdup
failure.
Link: https://lkml.kernel.org/r/20211015195550.22742-1-mathieu.desnoyers@efficios.com
Fixes: 64dc7f6958ef5 ("tracing/boot: Show correct histogram error command")
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
|
|
irq_cpu_{on,off}line() are now only used by the Octeon platform.
Make their use conditional on this plaform being enabled, and
otherwise hidden away.
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Tested-by: Serge Semin <fancer.lancer@gmail.com>
Link: https://lore.kernel.org/r/20211021170414.3341522-4-maz@kernel.org
|
|
Now that entry code handles IRQ entry (including setting the IRQ regs)
before calling irqchip code, irqchip code can safely call
generic_handle_domain_irq(), and there's no functional reason for it to
call handle_domain_irq().
Let's cement this split of responsibility and remove handle_domain_irq()
entirely, updating irqchip drivers to call generic_handle_domain_irq().
For consistency, handle_domain_nmi() is similarly removed and replaced
with a generic_handle_domain_nmi() function which also does not perform
any entry logic.
Previously handle_domain_{irq,nmi}() had a WARN_ON() which would fire
when they were called in an inappropriate context. So that we can
identify similar issues going forward, similar WARN_ON_ONCE() logic is
added to the generic_handle_*() functions, and comments are updated for
clarity and consistency.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
|
|
Now that all users of CONFIG_HANDLE_DOMAIN_IRQ perform the irq entry
work themselves, we can remove the legacy
CONFIG_HANDLE_DOMAIN_IRQ_IRQENTRY behaviour.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
|
|
New x86 FPU features will be very large, requiring ~10k of stack in
signal handlers. These new features require a new approach called
"dynamic features".
The kernel currently tries to ensure that altstacks are reasonably
sized. Right now, on x86, sys_sigaltstack() requires a size of >=2k.
However, that 2k is a constant. Simply raising that 2k requirement
to >10k for the new features would break existing apps which have a
compiled-in size of 2k.
Instead of universally enforcing a larger stack, prohibit a process from
using dynamic features without properly-sized altstacks. This must be
enforced in two places:
* A dynamic feature can not be enabled without an large-enough altstack
for each process thread.
* Once a dynamic feature is enabled, any request to install a too-small
altstack will be rejected
The dynamic feature enabling code must examine each thread in a
process to ensure that the altstacks are large enough. Add a new lock
(sigaltstack_lock()) to ensure that threads can not race and change
their altstack after being examined.
Add the infrastructure in form of a config option and provide empty
stubs for architectures which do not need dynamic altstack size checks.
This implementation will be fleshed out for x86 in a future patch called
x86/arch_prctl: Add controls for dynamic XSTATE components
[dhansen: commit message. ]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Chang S. Bae <chang.seok.bae@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20211021225527.10184-2-chang.seok.bae@intel.com
|
|
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: 54357f0c9149 ("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: 54357f0c9149 ("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>
|
|
It is useful to trace functions in kernel/event/core.c. Allow ftrace for
them by removing $(CC_FLAGS_FTRACE) from Makefile.
Link: https://lkml.kernel.org/r/20211006210732.2826289-1-songliubraving@fb.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: KP Singh <kpsingh@kernel.org>
Signed-off-by: Song Liu <songliubraving@fb.com>
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: cafb168a1c92 ("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>
|
|
On the real systems, the cgroups hierarchies are setup early and just
once by the node controller, so, other than number of cgroups, all
information in /proc/cgroups remain same for the system uptime. Let's
remove the cgroup_mutex usage on reading /proc/cgroups. There is a
chance of inconsistent number of cgroups for co-mounted cgroups while
printing the information from /proc/cgroups but that is not a big
issue. In addition /proc/cgroups is a v1 specific interface, so the
dependency on it should reduce over time.
The main motivation for removing the cgroup_mutex from /proc/cgroups is
to reduce the avenues of its contention. On our fleet, we have observed
buggy application hammering on /proc/cgroups and drastically slowing
down the node controller on the system which have many negative
consequences on other workloads running on the system.
Signed-off-by: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
|
|
The function cgroupstats_build extracts cgroup from the kernfs_node's
priv pointer which is a RCU pointer. So, there is no need to grab
cgroup_mutex. Just get the reference on the cgroup before using and
remove the cgroup_mutex altogether.
Signed-off-by: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
|
|
Currently cgroup_get_from_path() and cgroup_get_from_id() grab
cgroup_mutex before traversing the default hierarchy to find the
kernfs_node corresponding to the path/id and then extract the linked
cgroup. Since cgroup_mutex is still held, it is guaranteed that the
cgroup will be alive and the reference can be taken on it.
However similar guarantee can be provided without depending on the
cgroup_mutex and potentially reducing avenues of cgroup_mutex contentions.
The kernfs_node's priv pointer is RCU protected pointer and with just
rcu read lock we can grab the reference on the cgroup without
cgroup_mutex. So, remove cgroup_mutex from them.
Signed-off-by: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
|
|
Going forward we want architecture/entry code to perform all the
necessary work to enter/exit IRQ context, with irqchip code merely
handling the mapping of the interrupt to any handler(s). Among other
reasons, this is necessary to consistently fix some longstanding issues
with the ordering of lockdep/RCU/tracing instrumentation which many
architectures get wrong today in their entry code.
Importantly, rcu_irq_{enter,exit}() must be called precisely once per
IRQ exception, so that rcu_is_cpu_rrupt_from_idle() can correctly
identify when an interrupt was taken from an idle context which must be
explicitly preempted. Currently handle_domain_irq() calls
rcu_irq_{enter,exit}() via irq_{enter,exit}(), but entry code needs to
be able to call rcu_irq_{enter,exit}() earlier for correct ordering
across lockdep/RCU/tracing updates for sequences such as:
lockdep_hardirqs_off(CALLER_ADDR0);
rcu_irq_enter();
trace_hardirqs_off_finish();
To permit each architecture to be converted to the new style in turn,
this patch adds a new CONFIG_HANDLE_DOMAIN_IRQ_IRQENTRY selected by all
current users of HANDLE_DOMAIN_IRQ, which gates the existing behaviour.
When CONFIG_HANDLE_DOMAIN_IRQ_IRQENTRY is not selected,
handle_domain_irq() requires entry code to perform the
irq_{enter,exit}() work, with an explicit check for this matching the
style of handle_domain_nmi().
Subsequent patches will:
1) Add the necessary IRQ entry accounting to each architecture in turn,
dropping CONFIG_HANDLE_DOMAIN_IRQ_IRQENTRY from that architecture's
Kconfig.
2) Remove CONFIG_HANDLE_DOMAIN_IRQ_IRQENTRY once it is no longer
selected.
3) Convert irqchip drivers to consistently use
generic_handle_domain_irq() rather than handle_domain_irq().
4) Remove handle_domain_irq() and CONFIG_HANDLE_DOMAIN_IRQ.
... which should leave us with a clear split of responsiblity across the
entry and irqchip code, making it possible to perform additional
cleanups and fixes for the aforementioned longstanding issues with entry
code.
There should be no functional change as a result of this patch.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
|
