forked from luck/tmp_suning_uos_patched
22eb78792e
21715 Commits
| Author | SHA1 | Message | Date | |
|---|---|---|---|---|
Andrii Nakryiko
|
22eb78792e |
tools/bpftool: Fix skeleton codegen
Remove unnecessary check at the end of codegen() routine which makes codegen()
to always fail and exit bpftool with error code. Positive value of variable
n is not an indicator of a failure.
Fixes:
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Tobias Klauser
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2c4779eff8 |
tools, bpftool: Exit on error in function codegen
Currently, the codegen function might fail and return an error. But its callers continue without checking its return value. Since codegen can fail only in the unlikely case of the system running out of memory or the static template being malformed, just exit(-1) directly from codegen and make it void-returning. Suggested-by: Andrii Nakryiko <andrii.nakryiko@gmail.com> Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200611103341.21532-1-tklauser@distanz.ch |
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Tobias Klauser
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d4060ac969 |
tools, bpftool: Fix memory leak in codegen error cases
Free the memory allocated for the template on error paths in function codegen. Signed-off-by: Tobias Klauser <tklauser@distanz.ch> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200610130804.21423-1-tklauser@distanz.ch |
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YiFei Zhu
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bd6fecb9a9 |
selftests/bpf: Add cgroup_skb/egress test for load_bytes_relative
When cgroup_skb/egress triggers the MAC header is not set. Added a test that asserts reading MAC header is a -EFAULT but NET header succeeds. The test result from within the eBPF program is stored in an 1-element array map that the userspace then reads and asserts on. Another assertion is added that reading from a large offset, past the end of packet, returns -EFAULT. Signed-off-by: YiFei Zhu <zhuyifei@google.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Stanislav Fomichev <sdf@google.com> Link: https://lore.kernel.org/bpf/9028ccbea4385a620e69c0a104f469ffd655c01e.1591812755.git.zhuyifei@google.com |
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Brett Mastbergen
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47f6bc4ce1 |
tools, bpf: Do not force gcc as CC
This allows transparent cross-compilation with CROSS_COMPILE by relying on |
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Andrii Nakryiko
|
32022fd97e |
libbpf: Handle GCC noreturn-turned-volatile quirk
Handle a GCC quirk of emitting extra volatile modifier in DWARF (and
subsequently preserved in BTF by pahole) for function pointers marked as
__attribute__((noreturn)). This was the way to mark such functions before GCC
2.5 added noreturn attribute. Drop such func_proto modifiers, similarly to how
it's done for array (also to handle GCC quirk/bug).
Such volatile attribute is emitted by GCC only, so existing selftests can't
express such test. Simple repro is like this (compiled with GCC + BTF
generated by pahole):
struct my_struct {
void __attribute__((noreturn)) (*fn)(int);
};
struct my_struct a;
Without this fix, output will be:
struct my_struct {
voidvolatile (*fn)(int);
};
With the fix:
struct my_struct {
void (*fn)(int);
};
Fixes:
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Arnaldo Carvalho de Melo
|
8ca8d4a841 |
libbpf: Define __WORDSIZE if not available
Some systems, such as Android, don't have a define for __WORDSIZE, do it in terms of __SIZEOF_LONG__, as done in perf since 2012: http://git.kernel.org/torvalds/c/3f34f6c0233ae055b5 For reference: https://gcc.gnu.org/onlinedocs/cpp/Common-Predefined-Macros.html I build tested it here and Andrii did some Travis CI build tests too. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20200608161150.GA3073@kernel.org |
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Jesper Dangaard Brouer
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042b1545fe |
bpf: Selftests and tools use struct bpf_devmap_val from uapi
Sync tools uapi bpf.h header file and update selftests that use struct bpf_devmap_val. Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/159170951195.2102545.1833108712124273987.stgit@firesoul |
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Lorenz Bauer
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248e00ac47 |
bpf: cgroup: Allow multi-attach program to replace itself
When using BPF_PROG_ATTACH to attach a program to a cgroup in BPF_F_ALLOW_MULTI mode, it is not possible to replace a program with itself. This is because the check for duplicate programs doesn't take the replacement program into account. Replacing a program with itself might seem weird, but it has some uses: first, it allows resetting the associated cgroup storage. Second, it makes the API consistent with the non-ALLOW_MULTI usage, where it is possible to replace a program with itself. Third, it aligns BPF_PROG_ATTACH with bpf_link, where replacing itself is also supported. Sice this code has been refactored a few times this change will only apply to v5.7 and later. Adjustments could be made to commit |
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Andrii Nakryiko
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1f2436229b |
selftests/bpf: Fix ringbuf selftest sample counting undeterminism
Fix test race, in which background poll can get either 5 or 6 samples,
depending on timing of notification. Prevent this by open-coding sample
triggering and forcing notification for the very last sample only.
Also switch to using atomic increments and exchanges for more obviously
reliable counting and checking. Additionally, check expected processed sample
counters for single-threaded use cases as well.
Fixes:
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Linus Torvalds
|
cb8e59cc87 |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next
Pull networking updates from David Miller:
1) Allow setting bluetooth L2CAP modes via socket option, from Luiz
Augusto von Dentz.
2) Add GSO partial support to igc, from Sasha Neftin.
3) Several cleanups and improvements to r8169 from Heiner Kallweit.
4) Add IF_OPER_TESTING link state and use it when ethtool triggers a
device self-test. From Andrew Lunn.
5) Start moving away from custom driver versions, use the globally
defined kernel version instead, from Leon Romanovsky.
6) Support GRO vis gro_cells in DSA layer, from Alexander Lobakin.
7) Allow hard IRQ deferral during NAPI, from Eric Dumazet.
8) Add sriov and vf support to hinic, from Luo bin.
9) Support Media Redundancy Protocol (MRP) in the bridging code, from
Horatiu Vultur.
10) Support netmap in the nft_nat code, from Pablo Neira Ayuso.
11) Allow UDPv6 encapsulation of ESP in the ipsec code, from Sabrina
Dubroca. Also add ipv6 support for espintcp.
12) Lots of ReST conversions of the networking documentation, from Mauro
Carvalho Chehab.
13) Support configuration of ethtool rxnfc flows in bcmgenet driver,
from Doug Berger.
14) Allow to dump cgroup id and filter by it in inet_diag code, from
Dmitry Yakunin.
15) Add infrastructure to export netlink attribute policies to
userspace, from Johannes Berg.
16) Several optimizations to sch_fq scheduler, from Eric Dumazet.
17) Fallback to the default qdisc if qdisc init fails because otherwise
a packet scheduler init failure will make a device inoperative. From
Jesper Dangaard Brouer.
18) Several RISCV bpf jit optimizations, from Luke Nelson.
19) Correct the return type of the ->ndo_start_xmit() method in several
drivers, it's netdev_tx_t but many drivers were using
'int'. From Yunjian Wang.
20) Add an ethtool interface for PHY master/slave config, from Oleksij
Rempel.
21) Add BPF iterators, from Yonghang Song.
22) Add cable test infrastructure, including ethool interfaces, from
Andrew Lunn. Marvell PHY driver is the first to support this
facility.
23) Remove zero-length arrays all over, from Gustavo A. R. Silva.
24) Calculate and maintain an explicit frame size in XDP, from Jesper
Dangaard Brouer.
25) Add CAP_BPF, from Alexei Starovoitov.
26) Support terse dumps in the packet scheduler, from Vlad Buslov.
27) Support XDP_TX bulking in dpaa2 driver, from Ioana Ciornei.
28) Add devm_register_netdev(), from Bartosz Golaszewski.
29) Minimize qdisc resets, from Cong Wang.
30) Get rid of kernel_getsockopt and kernel_setsockopt in order to
eliminate set_fs/get_fs calls. From Christoph Hellwig.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2517 commits)
selftests: net: ip_defrag: ignore EPERM
net_failover: fixed rollback in net_failover_open()
Revert "tipc: Fix potential tipc_aead refcnt leak in tipc_crypto_rcv"
Revert "tipc: Fix potential tipc_node refcnt leak in tipc_rcv"
vmxnet3: allow rx flow hash ops only when rss is enabled
hinic: add set_channels ethtool_ops support
selftests/bpf: Add a default $(CXX) value
tools/bpf: Don't use $(COMPILE.c)
bpf, selftests: Use bpf_probe_read_kernel
s390/bpf: Use bcr 0,%0 as tail call nop filler
s390/bpf: Maintain 8-byte stack alignment
selftests/bpf: Fix verifier test
selftests/bpf: Fix sample_cnt shared between two threads
bpf, selftests: Adapt cls_redirect to call csum_level helper
bpf: Add csum_level helper for fixing up csum levels
bpf: Fix up bpf_skb_adjust_room helper's skb csum setting
sfc: add missing annotation for efx_ef10_try_update_nic_stats_vf()
crypto/chtls: IPv6 support for inline TLS
Crypto/chcr: Fixes a coccinile check error
Crypto/chcr: Fixes compilations warnings
...
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Linus Torvalds
|
039aeb9deb |
ARM:
- Move the arch-specific code into arch/arm64/kvm
- Start the post-32bit cleanup
- Cherry-pick a few non-invasive pre-NV patches
x86:
- Rework of TLB flushing
- Rework of event injection, especially with respect to nested virtualization
- Nested AMD event injection facelift, building on the rework of generic code
and fixing a lot of corner cases
- Nested AMD live migration support
- Optimization for TSC deadline MSR writes and IPIs
- Various cleanups
- Asynchronous page fault cleanups (from tglx, common topic branch with tip tree)
- Interrupt-based delivery of asynchronous "page ready" events (host side)
- Hyper-V MSRs and hypercalls for guest debugging
- VMX preemption timer fixes
s390:
- Cleanups
Generic:
- switch vCPU thread wakeup from swait to rcuwait
The other architectures, and the guest side of the asynchronous page fault
work, will come next week.
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Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull kvm updates from Paolo Bonzini:
"ARM:
- Move the arch-specific code into arch/arm64/kvm
- Start the post-32bit cleanup
- Cherry-pick a few non-invasive pre-NV patches
x86:
- Rework of TLB flushing
- Rework of event injection, especially with respect to nested
virtualization
- Nested AMD event injection facelift, building on the rework of
generic code and fixing a lot of corner cases
- Nested AMD live migration support
- Optimization for TSC deadline MSR writes and IPIs
- Various cleanups
- Asynchronous page fault cleanups (from tglx, common topic branch
with tip tree)
- Interrupt-based delivery of asynchronous "page ready" events (host
side)
- Hyper-V MSRs and hypercalls for guest debugging
- VMX preemption timer fixes
s390:
- Cleanups
Generic:
- switch vCPU thread wakeup from swait to rcuwait
The other architectures, and the guest side of the asynchronous page
fault work, will come next week"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (256 commits)
KVM: selftests: fix rdtsc() for vmx_tsc_adjust_test
KVM: check userspace_addr for all memslots
KVM: selftests: update hyperv_cpuid with SynDBG tests
x86/kvm/hyper-v: Add support for synthetic debugger via hypercalls
x86/kvm/hyper-v: enable hypercalls regardless of hypercall page
x86/kvm/hyper-v: Add support for synthetic debugger interface
x86/hyper-v: Add synthetic debugger definitions
KVM: selftests: VMX preemption timer migration test
KVM: nVMX: Fix VMX preemption timer migration
x86/kvm/hyper-v: Explicitly align hcall param for kvm_hyperv_exit
KVM: x86/pmu: Support full width counting
KVM: x86/pmu: Tweak kvm_pmu_get_msr to pass 'struct msr_data' in
KVM: x86: announce KVM_FEATURE_ASYNC_PF_INT
KVM: x86: acknowledgment mechanism for async pf page ready notifications
KVM: x86: interrupt based APF 'page ready' event delivery
KVM: introduce kvm_read_guest_offset_cached()
KVM: rename kvm_arch_can_inject_async_page_present() to kvm_arch_can_dequeue_async_page_present()
KVM: x86: extend struct kvm_vcpu_pv_apf_data with token info
Revert "KVM: async_pf: Fix #DF due to inject "Page not Present" and "Page Ready" exceptions simultaneously"
KVM: VMX: Replace zero-length array with flexible-array
...
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Linus Torvalds
|
e7c93cbfe9 |
threads-v5.8
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Merge tag 'threads-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull thread updates from Christian Brauner:
"We have been discussing using pidfds to attach to namespaces for quite
a while and the patches have in one form or another already existed
for about a year. But I wanted to wait to see how the general api
would be received and adopted.
This contains the changes to make it possible to use pidfds to attach
to the namespaces of a process, i.e. they can be passed as the first
argument to the setns() syscall.
When only a single namespace type is specified the semantics are
equivalent to passing an nsfd. That means setns(nsfd, CLONE_NEWNET)
equals setns(pidfd, CLONE_NEWNET).
However, when a pidfd is passed, multiple namespace flags can be
specified in the second setns() argument and setns() will attach the
caller to all the specified namespaces all at once or to none of them.
Specifying 0 is not valid together with a pidfd. Here are just two
obvious examples:
setns(pidfd, CLONE_NEWPID | CLONE_NEWNS | CLONE_NEWNET);
setns(pidfd, CLONE_NEWUSER);
Allowing to also attach subsets of namespaces supports various
use-cases where callers setns to a subset of namespaces to retain
privilege, perform an action and then re-attach another subset of
namespaces.
Apart from significantly reducing the number of syscalls needed to
attach to all currently supported namespaces (eight "open+setns"
sequences vs just a single "setns()"), this also allows atomic setns
to a set of namespaces, i.e. either attaching to all namespaces
succeeds or we fail without having changed anything.
This is centered around a new internal struct nsset which holds all
information necessary for a task to switch to a new set of namespaces
atomically. Fwiw, with this change a pidfd becomes the only token
needed to interact with a container. I'm expecting this to be
picked-up by util-linux for nsenter rather soon.
Associated with this change is a shiny new test-suite dedicated to
setns() (for pidfds and nsfds alike)"
* tag 'threads-v5.8' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
selftests/pidfd: add pidfd setns tests
nsproxy: attach to namespaces via pidfds
nsproxy: add struct nsset
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Thadeu Lima de Souza Cascardo
|
065fcfd497 |
selftests: net: ip_defrag: ignore EPERM
When running with conntrack rules, the dropped overlap fragments may cause EPERM to be returned to sendto. Instead of completely failing, just ignore those errors and continue. If this causes packets with overlap fragments to be dropped as expected, that is okay. And if it causes packets that are expected to be received to be dropped, which should not happen, it will be detected as failure. Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
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Linus Torvalds
|
750a02ab8d |
for-5.8/block-2020-06-01
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Linus Torvalds
|
cfa3b8068b |
hmm related patches for 5.8
This series adds a selftest for hmm_range_fault() and several of the
DEVICE_PRIVATE migration related actions, and another simplification for
hmm_range_fault()'s API.
- Simplify hmm_range_fault() with a simpler return code, no
HMM_PFN_SPECIAL, and no customizable output PFN format
- Add a selftest for hmm_range_fault() and DEVICE_PRIVATE related
functionality
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Merge tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma
Pull hmm updates from Jason Gunthorpe:
"This series adds a selftest for hmm_range_fault() and several of the
DEVICE_PRIVATE migration related actions, and another simplification
for hmm_range_fault()'s API.
- Simplify hmm_range_fault() with a simpler return code, no
HMM_PFN_SPECIAL, and no customizable output PFN format
- Add a selftest for hmm_range_fault() and DEVICE_PRIVATE related
functionality"
* tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
MAINTAINERS: add HMM selftests
mm/hmm/test: add selftests for HMM
mm/hmm/test: add selftest driver for HMM
mm/hmm: remove the customizable pfn format from hmm_range_fault
mm/hmm: remove HMM_PFN_SPECIAL
drm/amdgpu: remove dead code after hmm_range_fault()
mm/hmm: make hmm_range_fault return 0 or -1
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Linus Torvalds
|
355ba37d75 |
Power management updates for 5.8-rc1
- Rework the system-wide PM driver flags to make them easier to
understand and use and update their documentation (Rafael Wysocki,
Alan Stern).
- Allow cpuidle governors to be switched at run time regardless of
the kernel configuration and update the related documentation
accordingly (Hanjun Guo).
- Improve the resume device handling in the user space hibernarion
interface code (Domenico Andreoli).
- Document the intel-speed-select sysfs interface (Srinivas
Pandruvada).
- Make the ACPI code handing suspend to idle print more debug
messages to help diagnose issues with it (Rafael Wysocki).
- Fix a helper routine in the cpufreq core and correct a typo in
the struct cpufreq_driver kerneldoc comment (Rafael Wysocki, Wang
Wenhu).
- Update cpufreq drivers:
* Make the intel_pstate driver start in the passive mode by
default on systems without HWP (Rafael Wysocki).
* Add i.MX7ULP support to the imx-cpufreq-dt driver and add
i.MX7ULP to the cpufreq-dt-platdev blacklist (Peng Fan).
* Convert the qoriq cpufreq driver to a platform one, make the
platform code create a suitable device object for it and add
platform dependencies to it (Mian Yousaf Kaukab, Geert
Uytterhoeven).
* Fix wrong compatible binding in the qcom driver (Ansuel Smith).
* Build the omap driver by default for ARCH_OMAP2PLUS (Anders
Roxell).
* Add r8a7742 SoC support to the dt cpufreq driver (Lad Prabhakar).
- Update cpuidle core and drivers:
* Fix three reference count leaks in error code paths in the
cpuidle core (Qiushi Wu).
* Convert Qualcomm SPM to a generic cpuidle driver (Stephan
Gerhold).
* Fix up the execution order when entering a domain idle state in
the PSCI driver (Ulf Hansson).
- Fix a reference counting issue related to clock management and
clean up two oddities in the PM-runtime framework (Rafael Wysocki,
Andy Shevchenko).
- Add ElkhartLake support to the Intel RAPL power capping driver
and remove an unused local MSR definition from it (Jacob Pan,
Sumeet Pawnikar).
- Update devfreq core and drivers:
* Replace strncpy() with strscpy() in the devfreq core and use
lockdep asserts instead of manual checks for a locked mutex in
it (Dmitry Osipenko, Krzysztof Kozlowski).
* Add a generic imx bus scaling driver and make it register an
interconnect device (Leonard Crestez, Gustavo A. R. Silva).
* Make the cpufreq notifier in the tegra30 driver take boosting
into account and delete an unuseful error message from that
driver (Dmitry Osipenko, Markus Elfring).
- Remove unneeded semicolon from the cpupower code (Zou Wei).
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Merge tag 'pm-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management updates from Rafael Wysocki:
"These rework the system-wide PM driver flags, make runtime switching
of cpuidle governors easier, improve the user space hibernation
interface code, add intel-speed-select interface documentation, add
more debug messages to the ACPI code handling suspend to idle, update
the cpufreq core and drivers, fix a minor issue in the cpuidle core
and update two cpuidle drivers, improve the PM-runtime framework,
update the Intel RAPL power capping driver, update devfreq core and
drivers, and clean up the cpupower utility.
Specifics:
- Rework the system-wide PM driver flags to make them easier to
understand and use and update their documentation (Rafael Wysocki,
Alan Stern).
- Allow cpuidle governors to be switched at run time regardless of
the kernel configuration and update the related documentation
accordingly (Hanjun Guo).
- Improve the resume device handling in the user space hibernarion
interface code (Domenico Andreoli).
- Document the intel-speed-select sysfs interface (Srinivas
Pandruvada).
- Make the ACPI code handing suspend to idle print more debug
messages to help diagnose issues with it (Rafael Wysocki).
- Fix a helper routine in the cpufreq core and correct a typo in the
struct cpufreq_driver kerneldoc comment (Rafael Wysocki, Wang
Wenhu).
- Update cpufreq drivers:
- Make the intel_pstate driver start in the passive mode by
default on systems without HWP (Rafael Wysocki).
- Add i.MX7ULP support to the imx-cpufreq-dt driver and add
i.MX7ULP to the cpufreq-dt-platdev blacklist (Peng Fan).
- Convert the qoriq cpufreq driver to a platform one, make the
platform code create a suitable device object for it and add
platform dependencies to it (Mian Yousaf Kaukab, Geert
Uytterhoeven).
- Fix wrong compatible binding in the qcom driver (Ansuel Smith).
- Build the omap driver by default for ARCH_OMAP2PLUS (Anders
Roxell).
- Add r8a7742 SoC support to the dt cpufreq driver (Lad
Prabhakar).
- Update cpuidle core and drivers:
- Fix three reference count leaks in error code paths in the
cpuidle core (Qiushi Wu).
- Convert Qualcomm SPM to a generic cpuidle driver (Stephan
Gerhold).
- Fix up the execution order when entering a domain idle state in
the PSCI driver (Ulf Hansson).
- Fix a reference counting issue related to clock management and
clean up two oddities in the PM-runtime framework (Rafael Wysocki,
Andy Shevchenko).
- Add ElkhartLake support to the Intel RAPL power capping driver and
remove an unused local MSR definition from it (Jacob Pan, Sumeet
Pawnikar).
- Update devfreq core and drivers:
- Replace strncpy() with strscpy() in the devfreq core and use
lockdep asserts instead of manual checks for a locked mutex in
it (Dmitry Osipenko, Krzysztof Kozlowski).
- Add a generic imx bus scaling driver and make it register an
interconnect device (Leonard Crestez, Gustavo A. R. Silva).
- Make the cpufreq notifier in the tegra30 driver take boosting
into account and delete an unuseful error message from that
driver (Dmitry Osipenko, Markus Elfring).
- Remove unneeded semicolon from the cpupower code (Zou Wei)"
* tag 'pm-5.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (51 commits)
cpuidle: Fix three reference count leaks
PM: runtime: Replace pm_runtime_callbacks_present()
PM / devfreq: Use lockdep asserts instead of manual checks for locked mutex
PM / devfreq: imx-bus: Fix inconsistent IS_ERR and PTR_ERR
PM / devfreq: Replace strncpy with strscpy
PM / devfreq: imx: Register interconnect device
PM / devfreq: Add generic imx bus scaling driver
PM / devfreq: tegra30: Delete an error message in tegra_devfreq_probe()
PM / devfreq: tegra30: Make CPUFreq notifier to take into account boosting
PM: hibernate: Restrict writes to the resume device
PM: runtime: clk: Fix clk_pm_runtime_get() error path
cpuidle: Convert Qualcomm SPM driver to a generic CPUidle driver
ACPI: EC: PM: s2idle: Extend GPE dispatching debug message
ACPI: PM: s2idle: Print type of wakeup debug messages
powercap: RAPL: remove unused local MSR define
PM: runtime: Make clear what we do when conditions are wrong in rpm_suspend()
Documentation: admin-guide: pm: Document intel-speed-select
PM: hibernate: Split off snapshot dev option
PM: hibernate: Incorporate concurrency handling
Documentation: ABI: make current_governer_ro as a candidate for removal
...
|
||
|
Ilya Leoshkevich
|
e7ad28e6fd |
selftests/bpf: Add a default $(CXX) value
When using make kselftest TARGETS=bpf, tools/bpf is built with MAKEFLAGS=rR, which causes $(CXX) to be undefined, which in turn causes the build to fail with CXX test_cpp /bin/sh: 2: g: not found Fix by adding a default $(CXX) value, like tools/build/feature/Makefile already does. Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20200602175649.2501580-3-iii@linux.ibm.com |
||
|
Ilya Leoshkevich
|
d70a6be1e2 |
tools/bpf: Don't use $(COMPILE.c)
When using make kselftest TARGETS=bpf, tools/bpf is built with MAKEFLAGS=rR, which causes $(COMPILE.c) to be undefined, which in turn causes the build to fail with CC kselftest/bpf/tools/build/bpftool/map_perf_ring.o /bin/sh: 1: -MMD: not found Fix by using $(CC) $(CFLAGS) -c instead of $(COMPILE.c). Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20200602175649.2501580-2-iii@linux.ibm.com |
||
|
Linus Torvalds
|
a5a82e0a59 |
platform-drivers-x86 for v5.8-1
* Add a support of the media keys on the ASUS laptop UX325JA/UX425JA
* ASUS WMI driver can now handle 2-in-1 models T100TA, T100CHI, T100HA, T200TA
* Big refactoring of Intel SCU driver with Elkhart Lake support has been added
* Slim Bootloarder firmware update signaling WMI driver has been added
* Thinkpad ACPI driver can handle dual fan configuration on new P and X models
* Touchscreen DMI driver has been extended to support
- MP-man MPWIN895CL tablet
- ONDA V891 v5 tablet
- techBite Arc 11.6
- Trekstor Twin 10.1
- Trekstor Yourbook C11B
- Vinga J116
* Virtual Button driver got a few fixes to detect mode of 2-in-1 tablet models
* Intel Speed Select tools update
* Plenty of small cleanups here and there
The following is an automated git shortlog grouped by driver:
acerhdf:
- replace space by * in modalias
New drivers:
- Add Elkhart Lake SCU/PMC support
- Add Slim Bootloader firmware update signaling driver
asus-laptop:
- Drop duplicate check for led_classdev_unregister()
asus-nb-wmi:
- Revert "Do not load on Asus T100TA and T200TA"
- Do not load on Asus T100TA and T200TA
asus-wmi:
- Ignore WMI events with code 0x79
- Add support for SW_TABLET_MODE
- Move asus_wmi_input_init and _exit lower in the file
- Drop duplicate check for led_classdev_unregister()
- Reserve more space for struct bias_args
- remove redundant initialization of variable status
dcdbas:
- Check SMBIOS for protected buffer address
dell-laptop:
- don't register micmute LED if there is no token
dell-wmi:
- Ignore keyboard attached / detached events
device property:
- export set_secondary_fwnode() to modules
eeepc-laptop:
- Drop duplicate check for led_classdev_unregister()
hp-wmi:
- Introduce HPWMI_POWER_FW_OR_HW as convenient shortcut
- Convert simple_strtoul() to kstrtou32()
- Refactor postcode_store() to follow standard patterns
intel_cht_int33fe:
- Fix spelling issues
- Switch to use acpi_dev_hid_uid_match()
- Convert to use set_secondary_fwnode()
- Convert software node array to group
intel-hid:
- Add a quirk to support HP Spectre X2 (2015)
intel_mid_powerbtn:
- Convert to use new SCU IPC API
intel_pmc_core:
- avoid unused-function warnings
- Change Jasper Lake S0ix debug reg map back to ICL
intel_pmc_ipc:
- Convert to MFD
- Move PCI IDs to intel_scu_pcidrv.c
- Drop intel_pmc_ipc_command()
- Start using SCU IPC
intel_scu_ipc:
- Add managed function to register SCU IPC
- Introduce new SCU IPC API
- Move legacy SCU IPC API to a separate header
- Log more information if SCU IPC command fails
- Split out SCU IPC functionality from the SCU driver
intel_scu_ipcutil:
- Convert to use new SCU IPC API
intel-speed-select:
- Fix speed-select-base-freq-properties output on CLX-N
intel_telemetry:
- Add telemetry_get_pltdata()
- Convert to use new SCU IPC API
intel-vbtn:
- Only blacklist SW_TABLET_MODE on the 9 / "Laptop" chasis-type
- Detect switch position before registering the input-device
- Move detect_tablet_mode() to higher in the file
- Fix probe failure on devices with only switches
- Also handle tablet-mode switch on "Detachable" and "Portable" chassis-types
- Do not advertise switches to userspace if they are not there
- Split keymap into buttons and switches parts
- Use acpi_evaluate_integer()
ISST:
- Increase timeout
lg-laptop:
- Drop duplicate check for led_classdev_unregister()
MAINTAINERS:
- Add me as maintainer of Intel SCU drivers
- Update entry for Intel Broxton PMC driver
Merges of immutable branches:
- Merge branch 'for-next'
- Merge branch 'ib-mfd-x86-usb-watchdog-v5.7'
- Merge branch 'ib-pdx86-properties'
mfd:
- intel_soc_pmic_mrfld: Convert to use new SCU IPC API
- intel_soc_pmic_bxtwc: Convert to use new SCU IPC API
- intel_soc_pmic: Add SCU IPC member to struct intel_soc_pmic
samsung-laptop:
- Drop duplicate check for led_classdev_unregister()
software node:
- Allow register and unregister software node groups
sony-laptop:
- Make resuming thermal profile safer
- SNC calls should handle BUFFER types
thinkpad_acpi:
- Replace custom approach by kstrtoint()
- Use strndup_user() in dispatch_proc_write()
- Replace next_cmd(&buf) with strsep(&buf, ",")
- Drop duplicate check for led_classdev_unregister()
- Remove always false 'value < 0' statement
- Add support for dual fan control
tools/power/x86/intel-speed-select:
- Fix invalid core mask
- Increase CPU count
- Fix json perf-profile output output
- Update version
- Enable clos for turbo-freq enable
- Fix CLX-N package information output
- Check support status before enable
- Change debug to error
toshiba_acpi:
- Drop duplicate check for led_classdev_unregister()
touchscreen_dmi:
- Update Trekstor Twin 10.1 entry
- Add info for the Trekstor Yourbook C11B
- Drop comma in terminator line
- add Vinga J116 touchscreen
- Add info for the ONDA V891 v5 tablet
- Add touchscreen info for techBite Arc 11.6.
- Add info for the MP-man MPWIN895CL tablet
usb:
- typec: mux: Convert the Intel PMC Mux driver to use new SCU IPC API
watchdog:
- iTCO: fix link error
- intel-mid_wdt: Convert to use new SCU IPC API
wmi:
- Describe function parameters
- Fix indentation in some cases
- Replace UUID redefinitions by their originals
x86/platform/intel-mid:
- Add empty stubs for intel_scu_devices_[create|destroy]()
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Merge tag 'platform-drivers-x86-v5.8-1' of git://git.infradead.org/linux-platform-drivers-x86
Pull x86 platform driver updates from Andy Shevchenko:
- Add a support of the media keys on the ASUS laptop UX325JA/UX425JA
- ASUS WMI driver can now handle 2-in-1 models T100TA, T100CHI, T100HA,
T200TA
- Big refactoring of Intel SCU driver with Elkhart Lake support has
been added
- Slim Bootloarder firmware update signaling WMI driver has been added
- Thinkpad ACPI driver can handle dual fan configuration on new P and X
models
- Touchscreen DMI driver has been extended to support
- MP-man MPWIN895CL tablet
- ONDA V891 v5 tablet
- techBite Arc 11.6
- Trekstor Twin 10.1
- Trekstor Yourbook C11B
- Vinga J116
- Virtual Button driver got a few fixes to detect mode of 2-in-1 tablet
models
- Intel Speed Select tools update
- Plenty of small cleanups here and there
* tag 'platform-drivers-x86-v5.8-1' of git://git.infradead.org/linux-platform-drivers-x86: (89 commits)
platform/x86: dcdbas: Check SMBIOS for protected buffer address
platform/x86: asus_wmi: Reserve more space for struct bias_args
platform/x86: intel-vbtn: Only blacklist SW_TABLET_MODE on the 9 / "Laptop" chasis-type
platform/x86: intel-hid: Add a quirk to support HP Spectre X2 (2015)
platform/x86: touchscreen_dmi: Update Trekstor Twin 10.1 entry
platform/x86: touchscreen_dmi: Add info for the Trekstor Yourbook C11B
platform/x86: hp-wmi: Introduce HPWMI_POWER_FW_OR_HW as convenient shortcut
platform/x86: hp-wmi: Convert simple_strtoul() to kstrtou32()
platform/x86: hp-wmi: Refactor postcode_store() to follow standard patterns
platform/x86: acerhdf: replace space by * in modalias
platform/x86: ISST: Increase timeout
tools/power/x86/intel-speed-select: Fix invalid core mask
tools/power/x86/intel-speed-select: Increase CPU count
tools/power/x86/intel-speed-select: Fix json perf-profile output output
platform/x86: dell-wmi: Ignore keyboard attached / detached events
platform/x86: dell-laptop: don't register micmute LED if there is no token
platform/x86: thinkpad_acpi: Replace custom approach by kstrtoint()
platform/x86: thinkpad_acpi: Use strndup_user() in dispatch_proc_write()
platform/x86: thinkpad_acpi: Replace next_cmd(&buf) with strsep(&buf, ",")
platform/x86: intel-vbtn: Detect switch position before registering the input-device
...
|
||
|
Ilya Leoshkevich
|
9bc499befe |
bpf, selftests: Use bpf_probe_read_kernel
Since commit
|
||
|
Alexei Starovoitov
|
7cec0b9271 |
selftests/bpf: Fix verifier test
Adjust verifier test due to addition of new field.
Fixes:
|
||
|
Andrii Nakryiko
|
9a5f25ad30 |
selftests/bpf: Fix sample_cnt shared between two threads
Make sample_cnt volatile to fix possible selftests failure due to compiler
optimization preventing latest sample_cnt value to be visible to main thread.
sample_cnt is incremented in background thread, which is then joined into main
thread. So in terms of visibility sample_cnt update is ok. But because it's
not volatile, compiler might make optimizations that would prevent main thread
to see latest updated value. Fix this by marking global variable volatile.
Fixes:
|
||
|
Daniel Borkmann
|
c4ba153b65 |
bpf, selftests: Adapt cls_redirect to call csum_level helper
Adapt bpf_skb_adjust_room() to pass in BPF_F_ADJ_ROOM_NO_CSUM_RESET flag and use the new bpf_csum_level() helper to inc/dec the checksum level by one after the encap/decap. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Reviewed-by: Lorenz Bauer <lmb@cloudflare.com> Link: https://lore.kernel.org/bpf/e7458f10e3f3d795307cbc5ad870112671d9c6f7.1591108731.git.daniel@iogearbox.net |
||
|
Daniel Borkmann
|
7cdec54f97 |
bpf: Add csum_level helper for fixing up csum levels
Add a bpf_csum_level() helper which BPF programs can use in combination
with bpf_skb_adjust_room() when they pass in BPF_F_ADJ_ROOM_NO_CSUM_RESET
flag to the latter to avoid falling back to CHECKSUM_NONE.
The bpf_csum_level() allows to adjust CHECKSUM_UNNECESSARY skb->csum_levels
via BPF_CSUM_LEVEL_{INC,DEC} which calls __skb_{incr,decr}_checksum_unnecessary()
on the skb. The helper also allows a BPF_CSUM_LEVEL_RESET which sets the skb's
csum to CHECKSUM_NONE as well as a BPF_CSUM_LEVEL_QUERY to just return the
current level. Without this helper, there is no way to otherwise adjust the
skb->csum_level. I did not add an extra dummy flags as there is plenty of free
bitspace in level argument itself iff ever needed in future.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Alan Maguire <alan.maguire@oracle.com>
Acked-by: Lorenz Bauer <lmb@cloudflare.com>
Link: https://lore.kernel.org/bpf/279ae3717cb3d03c0ffeb511493c93c450a01e1a.1591108731.git.daniel@iogearbox.net
|
||
|
Daniel Borkmann
|
836e66c218 |
bpf: Fix up bpf_skb_adjust_room helper's skb csum setting
Lorenz recently reported:
In our TC classifier cls_redirect [0], we use the following sequence of
helper calls to decapsulate a GUE (basically IP + UDP + custom header)
encapsulated packet:
bpf_skb_adjust_room(skb, -encap_len, BPF_ADJ_ROOM_MAC, BPF_F_ADJ_ROOM_FIXED_GSO)
bpf_redirect(skb->ifindex, BPF_F_INGRESS)
It seems like some checksums of the inner headers are not validated in
this case. For example, a TCP SYN packet with invalid TCP checksum is
still accepted by the network stack and elicits a SYN ACK. [...]
That is, we receive the following packet from the driver:
| ETH | IP | UDP | GUE | IP | TCP |
skb->ip_summed == CHECKSUM_UNNECESSARY
ip_summed is CHECKSUM_UNNECESSARY because our NICs do rx checksum offloading.
On this packet we run skb_adjust_room_mac(-encap_len), and get the following:
| ETH | IP | TCP |
skb->ip_summed == CHECKSUM_UNNECESSARY
Note that ip_summed is still CHECKSUM_UNNECESSARY. After bpf_redirect()'ing
into the ingress, we end up in tcp_v4_rcv(). There, skb_checksum_init() is
turned into a no-op due to CHECKSUM_UNNECESSARY.
The bpf_skb_adjust_room() helper is not aware of protocol specifics. Internally,
it handles the CHECKSUM_COMPLETE case via skb_postpull_rcsum(), but that does
not cover CHECKSUM_UNNECESSARY. In this case skb->csum_level of the original
skb prior to bpf_skb_adjust_room() call was 0, that is, covering UDP. Right now
there is no way to adjust the skb->csum_level. NICs that have checksum offload
disabled (CHECKSUM_NONE) or that support CHECKSUM_COMPLETE are not affected.
Use a safe default for CHECKSUM_UNNECESSARY by resetting to CHECKSUM_NONE and
add a flag to the helper called BPF_F_ADJ_ROOM_NO_CSUM_RESET that allows users
from opting out. Opting out is useful for the case where we don't remove/add
full protocol headers, or for the case where a user wants to adjust the csum
level manually e.g. through bpf_csum_level() helper that is added in subsequent
patch.
The bpf_skb_proto_{4_to_6,6_to_4}() for NAT64/46 translation from the BPF
bpf_skb_change_proto() helper uses bpf_skb_net_hdr_{push,pop}() pair internally
as well but doesn't change layers, only transitions between v4 to v6 and vice
versa, therefore no adoption is required there.
[0] https://lore.kernel.org/bpf/20200424185556.7358-1-lmb@cloudflare.com/
Fixes:
|
||
|
Linus Torvalds
|
f359287765 |
Merge branch 'from-miklos' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs updates from Al Viro: "Assorted patches from Miklos. An interesting part here is /proc/mounts stuff..." The "/proc/mounts stuff" is using a cursor for keeeping the location data while traversing the mount listing. Also probably worth noting is the addition of faccessat2(), which takes an additional set of flags to specify how the lookup is done (AT_EACCESS, AT_SYMLINK_NOFOLLOW, AT_EMPTY_PATH). * 'from-miklos' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: vfs: add faccessat2 syscall vfs: don't parse "silent" option vfs: don't parse "posixacl" option vfs: don't parse forbidden flags statx: add mount_root statx: add mount ID statx: don't clear STATX_ATIME on SB_RDONLY uapi: deprecate STATX_ALL utimensat: AT_EMPTY_PATH support vfs: split out access_override_creds() proc/mounts: add cursor aio: fix async fsync creds vfs: allow unprivileged whiteout creation |
||
|
Linus Torvalds
|
b23c4771ff |
A fair amount of stuff this time around, dominated by yet another massive
set from Mauro toward the completion of the RST conversion. I *really* hope we are getting close to the end of this. Meanwhile, those patches reach pretty far afield to update document references around the tree; there should be no actual code changes there. There will be, alas, more of the usual trivial merge conflicts. Beyond that we have more translations, improvements to the sphinx scripting, a number of additions to the sysctl documentation, and lots of fixes. -----BEGIN PGP SIGNATURE----- iQFDBAABCAAtFiEEIw+MvkEiF49krdp9F0NaE2wMflgFAl7VId8PHGNvcmJldEBs d24ubmV0AAoJEBdDWhNsDH5Yq/gH/iaDgirQZV6UZ2v9sfwQNYolNpf2sKAuOZjd bPFB7WJoMQbKwQEvYrAUL2+5zPOcLYuIfzyOfo1BV1py+EyKbACcKjI4AedxfJF7 +NchmOBhlEqmEhzx2U08HRc4/8J223WG17fJRVsV3p+opJySexSFeQucfOciX5NR RUCxweWWyg/FgyqjkyMMTtsePqZPmcT5dWTlVXISlbWzcv5NFhuJXnSrw8Sfzcmm SJMzqItv3O+CabnKQ8kMLV2PozXTMfjeWH47ZUK0Y8/8PP9+cvqwFzZ0UDQJ1Xaz oyW/TqmunaXhfMsMFeFGSwtfgwRHvXdxkQdtwNHvo1dV4dzTvDw= =fDC/ -----END PGP SIGNATURE----- Merge tag 'docs-5.8' of git://git.lwn.net/linux Pull documentation updates from Jonathan Corbet: "A fair amount of stuff this time around, dominated by yet another massive set from Mauro toward the completion of the RST conversion. I *really* hope we are getting close to the end of this. Meanwhile, those patches reach pretty far afield to update document references around the tree; there should be no actual code changes there. There will be, alas, more of the usual trivial merge conflicts. Beyond that we have more translations, improvements to the sphinx scripting, a number of additions to the sysctl documentation, and lots of fixes" * tag 'docs-5.8' of git://git.lwn.net/linux: (130 commits) Documentation: fixes to the maintainer-entry-profile template zswap: docs/vm: Fix typo accept_threshold_percent in zswap.rst tracing: Fix events.rst section numbering docs: acpi: fix old http link and improve document format docs: filesystems: add info about efivars content Documentation: LSM: Correct the basic LSM description mailmap: change email for Ricardo Ribalda docs: sysctl/kernel: document unaligned controls Documentation: admin-guide: update bug-hunting.rst docs: sysctl/kernel: document ngroups_max nvdimm: fixes to maintainter-entry-profile Documentation/features: Correct RISC-V kprobes support entry Documentation/features: Refresh the arch support status files Revert "docs: sysctl/kernel: document ngroups_max" docs: move locking-specific documents to locking/ docs: move digsig docs to the security book docs: move the kref doc into the core-api book docs: add IRQ documentation at the core-api book docs: debugging-via-ohci1394.txt: add it to the core-api book docs: fix references for ipmi.rst file ... |
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Jakub Sitnicki
|
06716e04a0 |
selftests/bpf: Extend test_flow_dissector to cover link creation
Extend the existing flow_dissector test case to run tests once using direct prog attachments, and then for the second time using indirect attachment via link. The intention is to exercises the newly added high-level API for attaching programs to network namespace with links (bpf_program__attach_netns). Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200531082846.2117903-13-jakub@cloudflare.com |
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|
Jakub Sitnicki
|
b4b8a3bf9e |
selftests/bpf: Convert test_flow_dissector to use BPF skeleton
Switch flow dissector test setup from custom BPF object loader to BPF skeleton to save boilerplate and prepare for testing higher-level API for attaching flow dissector with bpf_link. To avoid depending on program order in the BPF object when populating the flow dissector PROG_ARRAY map, change the program section names to contain the program index into the map. This follows the example set by tailcall tests. Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200531082846.2117903-12-jakub@cloudflare.com |
||
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Jakub Sitnicki
|
b8215dce7d |
selftests/bpf, flow_dissector: Close TAP device FD after the test
test_flow_dissector leaves a TAP device after it's finished, potentially
interfering with other tests that will run after it. Fix it by closing the
TAP descriptor on cleanup.
Fixes:
|
||
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Jakub Sitnicki
|
1f043f87bb |
selftests/bpf: Add tests for attaching bpf_link to netns
Extend the existing test case for flow dissector attaching to cover: - link creation, - link updates, - link info querying, - mixing links with direct prog attachment. Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200531082846.2117903-10-jakub@cloudflare.com |
||
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Jakub Sitnicki
|
e948947a6e |
bpftool: Support link show for netns-attached links
Make `bpf link show` aware of new link type, that is links attached to
netns. When listing netns-attached links, display netns inode number as its
identifier and link attach type.
Sample session:
# readlink /proc/self/ns/net
net:[4026532251]
# bpftool prog show
357: flow_dissector tag a04f5eef06a7f555 gpl
loaded_at 2020-05-30T16:53:51+0200 uid 0
xlated 16B jited 37B memlock 4096B
358: flow_dissector tag a04f5eef06a7f555 gpl
loaded_at 2020-05-30T16:53:51+0200 uid 0
xlated 16B jited 37B memlock 4096B
# bpftool link show
108: netns prog 357
netns_ino 4026532251 attach_type flow_dissector
# bpftool link -jp show
[{
"id": 108,
"type": "netns",
"prog_id": 357,
"netns_ino": 4026532251,
"attach_type": "flow_dissector"
}
]
(... after netns is gone ...)
# bpftool link show
108: netns prog 357
netns_ino 0 attach_type flow_dissector
# bpftool link -jp show
[{
"id": 108,
"type": "netns",
"prog_id": 357,
"netns_ino": 0,
"attach_type": "flow_dissector"
}
]
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200531082846.2117903-9-jakub@cloudflare.com
|
||
|
Jakub Sitnicki
|
be6e19818b |
bpftool: Extract helpers for showing link attach type
Code for printing link attach_type is duplicated in a couple of places, and likely will be duplicated for future link types as well. Create helpers to prevent duplication. Suggested-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200531082846.2117903-8-jakub@cloudflare.com |
||
|
Jakub Sitnicki
|
d60d81acc2 |
libbpf: Add support for bpf_link-based netns attachment
Add bpf_program__attach_nets(), which uses LINK_CREATE subcommand to create an FD-based kernel bpf_link, for attach types tied to network namespace, that is BPF_FLOW_DISSECTOR for the moment. Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200531082846.2117903-7-jakub@cloudflare.com |
||
|
Jakub Sitnicki
|
7f045a49fe |
bpf: Add link-based BPF program attachment to network namespace
Extend bpf() syscall subcommands that operate on bpf_link, that is LINK_CREATE, LINK_UPDATE, OBJ_GET_INFO, to accept attach types tied to network namespaces (only flow dissector at the moment). Link-based and prog-based attachment can be used interchangeably, but only one can exist at a time. Attempts to attach a link when a prog is already attached directly, and the other way around, will be met with -EEXIST. Attempts to detach a program when link exists result in -EINVAL. Attachment of multiple links of same attach type to one netns is not supported with the intention to lift the restriction when a use-case presents itself. Because of that link create returns -E2BIG when trying to create another netns link, when one already exists. Link-based attachments to netns don't keep a netns alive by holding a ref to it. Instead links get auto-detached from netns when the latter is being destroyed, using a pernet pre_exit callback. When auto-detached, link lives in defunct state as long there are open FDs for it. -ENOLINK is returned if a user tries to update a defunct link. Because bpf_link to netns doesn't hold a ref to struct net, special care is taken when releasing, updating, or filling link info. The netns might be getting torn down when any of these link operations are in progress. That is why auto-detach and update/release/fill_info are synchronized by the same mutex. Also, link ops have to always check if auto-detach has not happened yet and if netns is still alive (refcnt > 0). Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20200531082846.2117903-5-jakub@cloudflare.com |
||
|
Linus Torvalds
|
533b220f7b |
arm64 updates for 5.8
- Branch Target Identification (BTI)
* Support for ARMv8.5-BTI in both user- and kernel-space. This
allows branch targets to limit the types of branch from which
they can be called and additionally prevents branching to
arbitrary code, although kernel support requires a very recent
toolchain.
* Function annotation via SYM_FUNC_START() so that assembly
functions are wrapped with the relevant "landing pad"
instructions.
* BPF and vDSO updates to use the new instructions.
* Addition of a new HWCAP and exposure of BTI capability to
userspace via ID register emulation, along with ELF loader
support for the BTI feature in .note.gnu.property.
* Non-critical fixes to CFI unwind annotations in the sigreturn
trampoline.
- Shadow Call Stack (SCS)
* Support for Clang's Shadow Call Stack feature, which reserves
platform register x18 to point at a separate stack for each
task that holds only return addresses. This protects function
return control flow from buffer overruns on the main stack.
* Save/restore of x18 across problematic boundaries (user-mode,
hypervisor, EFI, suspend, etc).
* Core support for SCS, should other architectures want to use it
too.
* SCS overflow checking on context-switch as part of the existing
stack limit check if CONFIG_SCHED_STACK_END_CHECK=y.
- CPU feature detection
* Removed numerous "SANITY CHECK" errors when running on a system
with mismatched AArch32 support at EL1. This is primarily a
concern for KVM, which disabled support for 32-bit guests on
such a system.
* Addition of new ID registers and fields as the architecture has
been extended.
- Perf and PMU drivers
* Minor fixes and cleanups to system PMU drivers.
- Hardware errata
* Unify KVM workarounds for VHE and nVHE configurations.
* Sort vendor errata entries in Kconfig.
- Secure Monitor Call Calling Convention (SMCCC)
* Update to the latest specification from Arm (v1.2).
* Allow PSCI code to query the SMCCC version.
- Software Delegated Exception Interface (SDEI)
* Unexport a bunch of unused symbols.
* Minor fixes to handling of firmware data.
- Pointer authentication
* Add support for dumping the kernel PAC mask in vmcoreinfo so
that the stack can be unwound by tools such as kdump.
* Simplification of key initialisation during CPU bringup.
- BPF backend
* Improve immediate generation for logical and add/sub
instructions.
- vDSO
- Minor fixes to the linker flags for consistency with other
architectures and support for LLVM's unwinder.
- Clean up logic to initialise and map the vDSO into userspace.
- ACPI
- Work around for an ambiguity in the IORT specification relating
to the "num_ids" field.
- Support _DMA method for all named components rather than only
PCIe root complexes.
- Minor other IORT-related fixes.
- Miscellaneous
* Initialise debug traps early for KGDB and fix KDB cacheflushing
deadlock.
* Minor tweaks to early boot state (documentation update, set
TEXT_OFFSET to 0x0, increase alignment of PE/COFF sections).
* Refactoring and cleanup
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Will Deacon:
"A sizeable pile of arm64 updates for 5.8.
Summary below, but the big two features are support for Branch Target
Identification and Clang's Shadow Call stack. The latter is currently
arm64-only, but the high-level parts are all in core code so it could
easily be adopted by other architectures pending toolchain support
Branch Target Identification (BTI):
- Support for ARMv8.5-BTI in both user- and kernel-space. This allows
branch targets to limit the types of branch from which they can be
called and additionally prevents branching to arbitrary code,
although kernel support requires a very recent toolchain.
- Function annotation via SYM_FUNC_START() so that assembly functions
are wrapped with the relevant "landing pad" instructions.
- BPF and vDSO updates to use the new instructions.
- Addition of a new HWCAP and exposure of BTI capability to userspace
via ID register emulation, along with ELF loader support for the
BTI feature in .note.gnu.property.
- Non-critical fixes to CFI unwind annotations in the sigreturn
trampoline.
Shadow Call Stack (SCS):
- Support for Clang's Shadow Call Stack feature, which reserves
platform register x18 to point at a separate stack for each task
that holds only return addresses. This protects function return
control flow from buffer overruns on the main stack.
- Save/restore of x18 across problematic boundaries (user-mode,
hypervisor, EFI, suspend, etc).
- Core support for SCS, should other architectures want to use it
too.
- SCS overflow checking on context-switch as part of the existing
stack limit check if CONFIG_SCHED_STACK_END_CHECK=y.
CPU feature detection:
- Removed numerous "SANITY CHECK" errors when running on a system
with mismatched AArch32 support at EL1. This is primarily a concern
for KVM, which disabled support for 32-bit guests on such a system.
- Addition of new ID registers and fields as the architecture has
been extended.
Perf and PMU drivers:
- Minor fixes and cleanups to system PMU drivers.
Hardware errata:
- Unify KVM workarounds for VHE and nVHE configurations.
- Sort vendor errata entries in Kconfig.
Secure Monitor Call Calling Convention (SMCCC):
- Update to the latest specification from Arm (v1.2).
- Allow PSCI code to query the SMCCC version.
Software Delegated Exception Interface (SDEI):
- Unexport a bunch of unused symbols.
- Minor fixes to handling of firmware data.
Pointer authentication:
- Add support for dumping the kernel PAC mask in vmcoreinfo so that
the stack can be unwound by tools such as kdump.
- Simplification of key initialisation during CPU bringup.
BPF backend:
- Improve immediate generation for logical and add/sub instructions.
vDSO:
- Minor fixes to the linker flags for consistency with other
architectures and support for LLVM's unwinder.
- Clean up logic to initialise and map the vDSO into userspace.
ACPI:
- Work around for an ambiguity in the IORT specification relating to
the "num_ids" field.
- Support _DMA method for all named components rather than only PCIe
root complexes.
- Minor other IORT-related fixes.
Miscellaneous:
- Initialise debug traps early for KGDB and fix KDB cacheflushing
deadlock.
- Minor tweaks to early boot state (documentation update, set
TEXT_OFFSET to 0x0, increase alignment of PE/COFF sections).
- Refactoring and cleanup"
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (148 commits)
KVM: arm64: Move __load_guest_stage2 to kvm_mmu.h
KVM: arm64: Check advertised Stage-2 page size capability
arm64/cpufeature: Add get_arm64_ftr_reg_nowarn()
ACPI/IORT: Remove the unused __get_pci_rid()
arm64/cpuinfo: Add ID_MMFR4_EL1 into the cpuinfo_arm64 context
arm64/cpufeature: Add remaining feature bits in ID_AA64PFR1 register
arm64/cpufeature: Add remaining feature bits in ID_AA64PFR0 register
arm64/cpufeature: Add remaining feature bits in ID_AA64ISAR0 register
arm64/cpufeature: Add remaining feature bits in ID_MMFR4 register
arm64/cpufeature: Add remaining feature bits in ID_PFR0 register
arm64/cpufeature: Introduce ID_MMFR5 CPU register
arm64/cpufeature: Introduce ID_DFR1 CPU register
arm64/cpufeature: Introduce ID_PFR2 CPU register
arm64/cpufeature: Make doublelock a signed feature in ID_AA64DFR0
arm64/cpufeature: Drop TraceFilt feature exposure from ID_DFR0 register
arm64/cpufeature: Add explicit ftr_id_isar0[] for ID_ISAR0 register
arm64: mm: Add asid_gen_match() helper
firmware: smccc: Fix missing prototype warning for arm_smccc_version_init
arm64: vdso: Fix CFI directives in sigreturn trampoline
arm64: vdso: Don't prefix sigreturn trampoline with a BTI C instruction
...
|
||
|
Andrii Nakryiko
|
febeb6dff7 |
libbpf: Add _GNU_SOURCE for reallocarray to ringbuf.c
On systems with recent enough glibc, reallocarray compat won't kick in, so
reallocarray() itself has to come from stdlib.h include. But _GNU_SOURCE is
necessary to enable it. So add it.
Fixes:
|
||
|
Ferenc Fejes
|
9c441fe4c0 |
selftests/bpf: Add test for SO_BINDTODEVICE opt of bpf_setsockopt
This test intended to verify if SO_BINDTODEVICE option works in bpf_setsockopt. Because we already in the SOL_SOCKET level in this connect bpf prog its safe to verify the sanity in the beginning of the connect_v4_prog by calling the bind_to_device test helper. The testing environment already created by the test_sock_addr.sh script so this test assume that two netdevices already existing in the system: veth pair with names test_sock_addr1 and test_sock_addr2. The test will try to bind the socket to those devices first. Then the test assume there are no netdevice with "nonexistent_dev" name so the bpf_setsockopt will give use ENODEV error. At the end the test remove the device binding from the socket by binding it to an empty name. Signed-off-by: Ferenc Fejes <fejes@inf.elte.hu> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/3f055b8e45c65639c5c73d0b4b6c589e60b86f15.1590871065.git.fejes@inf.elte.hu |
||
|
John Fastabend
|
463bac5f1c |
bpf, selftests: Add test for ktls with skb bpf ingress policy
This adds a test for bpf ingress policy. To ensure data writes happen as expected with extra TLS headers we run these tests with data verification enabled by default. This will test receive packets have "PASS" stamped into the front of the payload. Signed-off-by: John Fastabend <john.fastabend@gmail.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/159079363965.5745.3390806911628980210.stgit@john-Precision-5820-Tower Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
|
Alexei Starovoitov
|
df8fe57c07 |
tools/bpf: sync bpf.h
Sync bpf.h into tool/include/uapi/ Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
|
David Ahern
|
d39aec79e5 |
selftest: Add tests for XDP programs in devmap entries
Add tests to verify ability to add an XDP program to a entry in a DEVMAP. Add negative tests to show DEVMAP programs can not be attached to devices as a normal XDP program, and accesses to egress_ifindex require BPF_XDP_DEVMAP attach type. Signed-off-by: David Ahern <dsahern@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://lore.kernel.org/bpf/20200529220716.75383-6-dsahern@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
|
David Ahern
|
2778797037 |
libbpf: Add SEC name for xdp programs attached to device map
Support SEC("xdp_devmap*") as a short cut for loading the program with
type BPF_PROG_TYPE_XDP and expected attach type BPF_XDP_DEVMAP.
Signed-off-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20200529220716.75383-5-dsahern@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
||
|
David Ahern
|
64b59025c1 |
xdp: Add xdp_txq_info to xdp_buff
Add xdp_txq_info as the Tx counterpart to xdp_rxq_info. At the moment only the device is added. Other fields (queue_index) can be added as use cases arise. >From a UAPI perspective, add egress_ifindex to xdp context for bpf programs to see the Tx device. Update the verifier to only allow accesses to egress_ifindex by XDP programs with BPF_XDP_DEVMAP expected attach type. Signed-off-by: David Ahern <dsahern@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://lore.kernel.org/bpf/20200529220716.75383-4-dsahern@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
|
David Ahern
|
fbee97feed |
bpf: Add support to attach bpf program to a devmap entry
Add BPF_XDP_DEVMAP attach type for use with programs associated with a DEVMAP entry. Allow DEVMAPs to associate a program with a device entry by adding a bpf_prog.fd to 'struct bpf_devmap_val'. Values read show the program id, so the fd and id are a union. bpf programs can get access to the struct via vmlinux.h. The program associated with the fd must have type XDP with expected attach type BPF_XDP_DEVMAP. When a program is associated with a device index, the program is run on an XDP_REDIRECT and before the buffer is added to the per-cpu queue. At this point rxq data is still valid; the next patch adds tx device information allowing the prorgam to see both ingress and egress device indices. XDP generic is skb based and XDP programs do not work with skb's. Block the use case by walking maps used by a program that is to be attached via xdpgeneric and fail if any of them are DEVMAP / DEVMAP_HASH with Block attach of BPF_XDP_DEVMAP programs to devices. Signed-off-by: David Ahern <dsahern@kernel.org> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://lore.kernel.org/bpf/20200529220716.75383-3-dsahern@kernel.org Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
|
Andrii Nakryiko
|
c97099b0f2 |
bpf: Add BPF ringbuf and perf buffer benchmarks
Extend bench framework with ability to have benchmark-provided child argument
parser for custom benchmark-specific parameters. This makes bench generic code
modular and independent from any specific benchmark.
Also implement a set of benchmarks for new BPF ring buffer and existing perf
buffer. 4 benchmarks were implemented: 2 variations for each of BPF ringbuf
and perfbuf:,
- rb-libbpf utilizes stock libbpf ring_buffer manager for reading data;
- rb-custom implements custom ring buffer setup and reading code, to
eliminate overheads inherent in generic libbpf code due to callback
functions and the need to update consumer position after each consumed
record, instead of batching updates (due to pessimistic assumption that
user callback might take long time and thus could unnecessarily hold ring
buffer space for too long);
- pb-libbpf uses stock libbpf perf_buffer code with all the default
settings, though uses higher-performance raw event callback to minimize
unnecessary overhead;
- pb-custom implements its own custom consumer code to minimize any possible
overhead of generic libbpf implementation and indirect function calls.
All of the test support default, no data notification skipped, mode, as well
as sampled mode (with --rb-sampled flag), which allows to trigger epoll
notification less frequently and reduce overhead. As will be shown, this mode
is especially critical for perf buffer, which suffers from high overhead of
wakeups in kernel.
Otherwise, all benchamrks implement similar way to generate a batch of records
by using fentry/sys_getpgid BPF program, which pushes a bunch of records in
a tight loop and records number of successful and dropped samples. Each record
is a small 8-byte integer, to minimize the effect of memory copying with
bpf_perf_event_output() and bpf_ringbuf_output().
Benchmarks that have only one producer implement optional back-to-back mode,
in which record production and consumption is alternating on the same CPU.
This is the highest-throughput happy case, showing ultimate performance
achievable with either BPF ringbuf or perfbuf.
All the below scenarios are implemented in a script in
benchs/run_bench_ringbufs.sh. Tests were performed on 28-core/56-thread
Intel Xeon CPU E5-2680 v4 @ 2.40GHz CPU.
Single-producer, parallel producer
==================================
rb-libbpf 12.054 ± 0.320M/s (drops 0.000 ± 0.000M/s)
rb-custom 8.158 ± 0.118M/s (drops 0.001 ± 0.003M/s)
pb-libbpf 0.931 ± 0.007M/s (drops 0.000 ± 0.000M/s)
pb-custom 0.965 ± 0.003M/s (drops 0.000 ± 0.000M/s)
Single-producer, parallel producer, sampled notification
========================================================
rb-libbpf 11.563 ± 0.067M/s (drops 0.000 ± 0.000M/s)
rb-custom 15.895 ± 0.076M/s (drops 0.000 ± 0.000M/s)
pb-libbpf 9.889 ± 0.032M/s (drops 0.000 ± 0.000M/s)
pb-custom 9.866 ± 0.028M/s (drops 0.000 ± 0.000M/s)
Single producer on one CPU, consumer on another one, both running at full
speed. Curiously, rb-libbpf has higher throughput than objectively faster (due
to more lightweight consumer code path) rb-custom. It appears that faster
consumer causes kernel to send notifications more frequently, because consumer
appears to be caught up more frequently. Performance of perfbuf suffers from
default "no sampling" policy and huge overhead that causes.
In sampled mode, rb-custom is winning very significantly eliminating too
frequent in-kernel wakeups, the gain appears to be more than 2x.
Perf buffer achieves even more impressive wins, compared to stock perfbuf
settings, with 10x improvements in throughput with 1:500 sampling rate. The
trade-off is that with sampling, application might not get next X events until
X+1st arrives, which is not always acceptable. With steady influx of events,
though, this shouldn't be a problem.
Overall, single-producer performance of ring buffers seems to be better no
matter the sampled/non-sampled modes, but it especially beats ring buffer
without sampling due to its adaptive notification approach.
Single-producer, back-to-back mode
==================================
rb-libbpf 15.507 ± 0.247M/s (drops 0.000 ± 0.000M/s)
rb-libbpf-sampled 14.692 ± 0.195M/s (drops 0.000 ± 0.000M/s)
rb-custom 21.449 ± 0.157M/s (drops 0.000 ± 0.000M/s)
rb-custom-sampled 20.024 ± 0.386M/s (drops 0.000 ± 0.000M/s)
pb-libbpf 1.601 ± 0.015M/s (drops 0.000 ± 0.000M/s)
pb-libbpf-sampled 8.545 ± 0.064M/s (drops 0.000 ± 0.000M/s)
pb-custom 1.607 ± 0.022M/s (drops 0.000 ± 0.000M/s)
pb-custom-sampled 8.988 ± 0.144M/s (drops 0.000 ± 0.000M/s)
Here we test a back-to-back mode, which is arguably best-case scenario both
for BPF ringbuf and perfbuf, because there is no contention and for ringbuf
also no excessive notification, because consumer appears to be behind after
the first record. For ringbuf, custom consumer code clearly wins with 21.5 vs
16 million records per second exchanged between producer and consumer. Sampled
mode actually hurts a bit due to slightly slower producer logic (it needs to
fetch amount of data available to decide whether to skip or force notification).
Perfbuf with wakeup sampling gets 5.5x throughput increase, compared to
no-sampling version. There also doesn't seem to be noticeable overhead from
generic libbpf handling code.
Perfbuf back-to-back, effect of sample rate
===========================================
pb-sampled-1 1.035 ± 0.012M/s (drops 0.000 ± 0.000M/s)
pb-sampled-5 3.476 ± 0.087M/s (drops 0.000 ± 0.000M/s)
pb-sampled-10 5.094 ± 0.136M/s (drops 0.000 ± 0.000M/s)
pb-sampled-25 7.118 ± 0.153M/s (drops 0.000 ± 0.000M/s)
pb-sampled-50 8.169 ± 0.156M/s (drops 0.000 ± 0.000M/s)
pb-sampled-100 8.887 ± 0.136M/s (drops 0.000 ± 0.000M/s)
pb-sampled-250 9.180 ± 0.209M/s (drops 0.000 ± 0.000M/s)
pb-sampled-500 9.353 ± 0.281M/s (drops 0.000 ± 0.000M/s)
pb-sampled-1000 9.411 ± 0.217M/s (drops 0.000 ± 0.000M/s)
pb-sampled-2000 9.464 ± 0.167M/s (drops 0.000 ± 0.000M/s)
pb-sampled-3000 9.575 ± 0.273M/s (drops 0.000 ± 0.000M/s)
This benchmark shows the effect of event sampling for perfbuf. Back-to-back
mode for highest throughput. Just doing every 5th record notification gives
3.5x speed up. 250-500 appears to be the point of diminishing return, with
almost 9x speed up. Most benchmarks use 500 as the default sampling for pb-raw
and pb-custom.
Ringbuf back-to-back, effect of sample rate
===========================================
rb-sampled-1 1.106 ± 0.010M/s (drops 0.000 ± 0.000M/s)
rb-sampled-5 4.746 ± 0.149M/s (drops 0.000 ± 0.000M/s)
rb-sampled-10 7.706 ± 0.164M/s (drops 0.000 ± 0.000M/s)
rb-sampled-25 12.893 ± 0.273M/s (drops 0.000 ± 0.000M/s)
rb-sampled-50 15.961 ± 0.361M/s (drops 0.000 ± 0.000M/s)
rb-sampled-100 18.203 ± 0.445M/s (drops 0.000 ± 0.000M/s)
rb-sampled-250 19.962 ± 0.786M/s (drops 0.000 ± 0.000M/s)
rb-sampled-500 20.881 ± 0.551M/s (drops 0.000 ± 0.000M/s)
rb-sampled-1000 21.317 ± 0.532M/s (drops 0.000 ± 0.000M/s)
rb-sampled-2000 21.331 ± 0.535M/s (drops 0.000 ± 0.000M/s)
rb-sampled-3000 21.688 ± 0.392M/s (drops 0.000 ± 0.000M/s)
Similar benchmark for ring buffer also shows a great advantage (in terms of
throughput) of skipping notifications. Skipping every 5th one gives 4x boost.
Also similar to perfbuf case, 250-500 seems to be the point of diminishing
returns, giving roughly 20x better results.
Keep in mind, for this test, notifications are controlled manually with
BPF_RB_NO_WAKEUP and BPF_RB_FORCE_WAKEUP. As can be seen from previous
benchmarks, adaptive notifications based on consumer's positions provides same
(or even slightly better due to simpler load generator on BPF side) benefits in
favorable back-to-back scenario. Over zealous and fast consumer, which is
almost always caught up, will make thoughput numbers smaller. That's the case
when manual notification control might prove to be extremely beneficial.
Ringbuf back-to-back, reserve+commit vs output
==============================================
reserve 22.819 ± 0.503M/s (drops 0.000 ± 0.000M/s)
output 18.906 ± 0.433M/s (drops 0.000 ± 0.000M/s)
Ringbuf sampled, reserve+commit vs output
=========================================
reserve-sampled 15.350 ± 0.132M/s (drops 0.000 ± 0.000M/s)
output-sampled 14.195 ± 0.144M/s (drops 0.000 ± 0.000M/s)
BPF ringbuf supports two sets of APIs with various usability and performance
tradeoffs: bpf_ringbuf_reserve()+bpf_ringbuf_commit() vs bpf_ringbuf_output().
This benchmark clearly shows superiority of reserve+commit approach, despite
using a small 8-byte record size.
Single-producer, consumer/producer competing on the same CPU, low batch count
=============================================================================
rb-libbpf 3.045 ± 0.020M/s (drops 3.536 ± 0.148M/s)
rb-custom 3.055 ± 0.022M/s (drops 3.893 ± 0.066M/s)
pb-libbpf 1.393 ± 0.024M/s (drops 0.000 ± 0.000M/s)
pb-custom 1.407 ± 0.016M/s (drops 0.000 ± 0.000M/s)
This benchmark shows one of the worst-case scenarios, in which producer and
consumer do not coordinate *and* fight for the same CPU. No batch count and
sampling settings were able to eliminate drops for ringbuffer, producer is
just too fast for consumer to keep up. But ringbuf and perfbuf still able to
pass through quite a lot of messages, which is more than enough for a lot of
applications.
Ringbuf, multi-producer contention
==================================
rb-libbpf nr_prod 1 10.916 ± 0.399M/s (drops 0.000 ± 0.000M/s)
rb-libbpf nr_prod 2 4.931 ± 0.030M/s (drops 0.000 ± 0.000M/s)
rb-libbpf nr_prod 3 4.880 ± 0.006M/s (drops 0.000 ± 0.000M/s)
rb-libbpf nr_prod 4 3.926 ± 0.004M/s (drops 0.000 ± 0.000M/s)
rb-libbpf nr_prod 8 4.011 ± 0.004M/s (drops 0.000 ± 0.000M/s)
rb-libbpf nr_prod 12 3.967 ± 0.016M/s (drops 0.000 ± 0.000M/s)
rb-libbpf nr_prod 16 2.604 ± 0.030M/s (drops 0.001 ± 0.002M/s)
rb-libbpf nr_prod 20 2.233 ± 0.003M/s (drops 0.000 ± 0.000M/s)
rb-libbpf nr_prod 24 2.085 ± 0.015M/s (drops 0.000 ± 0.000M/s)
rb-libbpf nr_prod 28 2.055 ± 0.004M/s (drops 0.000 ± 0.000M/s)
rb-libbpf nr_prod 32 1.962 ± 0.004M/s (drops 0.000 ± 0.000M/s)
rb-libbpf nr_prod 36 2.089 ± 0.005M/s (drops 0.000 ± 0.000M/s)
rb-libbpf nr_prod 40 2.118 ± 0.006M/s (drops 0.000 ± 0.000M/s)
rb-libbpf nr_prod 44 2.105 ± 0.004M/s (drops 0.000 ± 0.000M/s)
rb-libbpf nr_prod 48 2.120 ± 0.058M/s (drops 0.000 ± 0.001M/s)
rb-libbpf nr_prod 52 2.074 ± 0.024M/s (drops 0.007 ± 0.014M/s)
Ringbuf uses a very short-duration spinlock during reservation phase, to check
few invariants, increment producer count and set record header. This is the
biggest point of contention for ringbuf implementation. This benchmark
evaluates the effect of multiple competing writers on overall throughput of
a single shared ringbuffer.
Overall throughput drops almost 2x when going from single to two
highly-contended producers, gradually dropping with additional competing
producers. Performance drop stabilizes at around 20 producers and hovers
around 2mln even with 50+ fighting producers, which is a 5x drop compared to
non-contended case. Good kernel implementation in kernel helps maintain decent
performance here.
Note, that in the intended real-world scenarios, it's not expected to get even
close to such a high levels of contention. But if contention will become
a problem, there is always an option of sharding few ring buffers across a set
of CPUs.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200529075424.3139988-5-andriin@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
||
|
Andrii Nakryiko
|
cb1c9ddd55 |
selftests/bpf: Add BPF ringbuf selftests
Both singleton BPF ringbuf and BPF ringbuf with map-in-map use cases are tested. Also reserve+submit/discards and output variants of API are validated. Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20200529075424.3139988-4-andriin@fb.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |
||
|
Andrii Nakryiko
|
bf99c936f9 |
libbpf: Add BPF ring buffer support
Declaring and instantiating BPF ring buffer doesn't require any changes to
libbpf, as it's just another type of maps. So using existing BTF-defined maps
syntax with __uint(type, BPF_MAP_TYPE_RINGBUF) and __uint(max_elements,
<size-of-ring-buf>) is all that's necessary to create and use BPF ring buffer.
This patch adds BPF ring buffer consumer to libbpf. It is very similar to
perf_buffer implementation in terms of API, but also attempts to fix some
minor problems and inconveniences with existing perf_buffer API.
ring_buffer support both single ring buffer use case (with just using
ring_buffer__new()), as well as allows to add more ring buffers, each with its
own callback and context. This allows to efficiently poll and consume
multiple, potentially completely independent, ring buffers, using single
epoll instance.
The latter is actually a problem in practice for applications
that are using multiple sets of perf buffers. They have to create multiple
instances for struct perf_buffer and poll them independently or in a loop,
each approach having its own problems (e.g., inability to use a common poll
timeout). struct ring_buffer eliminates this problem by aggregating many
independent ring buffer instances under the single "ring buffer manager".
Second, perf_buffer's callback can't return error, so applications that need
to stop polling due to error in data or data signalling the end, have to use
extra mechanisms to signal that polling has to stop. ring_buffer's callback
can return error, which will be passed through back to user code and can be
acted upon appropariately.
Two APIs allow to consume ring buffer data:
- ring_buffer__poll(), which will wait for data availability notification
and will consume data only from reported ring buffer(s); this API allows
to efficiently use resources by reading data only when it becomes
available;
- ring_buffer__consume(), will attempt to read new records regardless of
data availablity notification sub-system. This API is useful for cases
when lowest latency is required, in expense of burning CPU resources.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200529075424.3139988-3-andriin@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
||
|
Andrii Nakryiko
|
457f44363a |
bpf: Implement BPF ring buffer and verifier support for it
This commit adds a new MPSC ring buffer implementation into BPF ecosystem,
which allows multiple CPUs to submit data to a single shared ring buffer. On
the consumption side, only single consumer is assumed.
Motivation
----------
There are two distinctive motivators for this work, which are not satisfied by
existing perf buffer, which prompted creation of a new ring buffer
implementation.
- more efficient memory utilization by sharing ring buffer across CPUs;
- preserving ordering of events that happen sequentially in time, even
across multiple CPUs (e.g., fork/exec/exit events for a task).
These two problems are independent, but perf buffer fails to satisfy both.
Both are a result of a choice to have per-CPU perf ring buffer. Both can be
also solved by having an MPSC implementation of ring buffer. The ordering
problem could technically be solved for perf buffer with some in-kernel
counting, but given the first one requires an MPSC buffer, the same solution
would solve the second problem automatically.
Semantics and APIs
------------------
Single ring buffer is presented to BPF programs as an instance of BPF map of
type BPF_MAP_TYPE_RINGBUF. Two other alternatives considered, but ultimately
rejected.
One way would be to, similar to BPF_MAP_TYPE_PERF_EVENT_ARRAY, make
BPF_MAP_TYPE_RINGBUF could represent an array of ring buffers, but not enforce
"same CPU only" rule. This would be more familiar interface compatible with
existing perf buffer use in BPF, but would fail if application needed more
advanced logic to lookup ring buffer by arbitrary key. HASH_OF_MAPS addresses
this with current approach. Additionally, given the performance of BPF
ringbuf, many use cases would just opt into a simple single ring buffer shared
among all CPUs, for which current approach would be an overkill.
Another approach could introduce a new concept, alongside BPF map, to
represent generic "container" object, which doesn't necessarily have key/value
interface with lookup/update/delete operations. This approach would add a lot
of extra infrastructure that has to be built for observability and verifier
support. It would also add another concept that BPF developers would have to
familiarize themselves with, new syntax in libbpf, etc. But then would really
provide no additional benefits over the approach of using a map.
BPF_MAP_TYPE_RINGBUF doesn't support lookup/update/delete operations, but so
doesn't few other map types (e.g., queue and stack; array doesn't support
delete, etc).
The approach chosen has an advantage of re-using existing BPF map
infrastructure (introspection APIs in kernel, libbpf support, etc), being
familiar concept (no need to teach users a new type of object in BPF program),
and utilizing existing tooling (bpftool). For common scenario of using
a single ring buffer for all CPUs, it's as simple and straightforward, as
would be with a dedicated "container" object. On the other hand, by being
a map, it can be combined with ARRAY_OF_MAPS and HASH_OF_MAPS map-in-maps to
implement a wide variety of topologies, from one ring buffer for each CPU
(e.g., as a replacement for perf buffer use cases), to a complicated
application hashing/sharding of ring buffers (e.g., having a small pool of
ring buffers with hashed task's tgid being a look up key to preserve order,
but reduce contention).
Key and value sizes are enforced to be zero. max_entries is used to specify
the size of ring buffer and has to be a power of 2 value.
There are a bunch of similarities between perf buffer
(BPF_MAP_TYPE_PERF_EVENT_ARRAY) and new BPF ring buffer semantics:
- variable-length records;
- if there is no more space left in ring buffer, reservation fails, no
blocking;
- memory-mappable data area for user-space applications for ease of
consumption and high performance;
- epoll notifications for new incoming data;
- but still the ability to do busy polling for new data to achieve the
lowest latency, if necessary.
BPF ringbuf provides two sets of APIs to BPF programs:
- bpf_ringbuf_output() allows to *copy* data from one place to a ring
buffer, similarly to bpf_perf_event_output();
- bpf_ringbuf_reserve()/bpf_ringbuf_commit()/bpf_ringbuf_discard() APIs
split the whole process into two steps. First, a fixed amount of space is
reserved. If successful, a pointer to a data inside ring buffer data area
is returned, which BPF programs can use similarly to a data inside
array/hash maps. Once ready, this piece of memory is either committed or
discarded. Discard is similar to commit, but makes consumer ignore the
record.
bpf_ringbuf_output() has disadvantage of incurring extra memory copy, because
record has to be prepared in some other place first. But it allows to submit
records of the length that's not known to verifier beforehand. It also closely
matches bpf_perf_event_output(), so will simplify migration significantly.
bpf_ringbuf_reserve() avoids the extra copy of memory by providing a memory
pointer directly to ring buffer memory. In a lot of cases records are larger
than BPF stack space allows, so many programs have use extra per-CPU array as
a temporary heap for preparing sample. bpf_ringbuf_reserve() avoid this needs
completely. But in exchange, it only allows a known constant size of memory to
be reserved, such that verifier can verify that BPF program can't access
memory outside its reserved record space. bpf_ringbuf_output(), while slightly
slower due to extra memory copy, covers some use cases that are not suitable
for bpf_ringbuf_reserve().
The difference between commit and discard is very small. Discard just marks
a record as discarded, and such records are supposed to be ignored by consumer
code. Discard is useful for some advanced use-cases, such as ensuring
all-or-nothing multi-record submission, or emulating temporary malloc()/free()
within single BPF program invocation.
Each reserved record is tracked by verifier through existing
reference-tracking logic, similar to socket ref-tracking. It is thus
impossible to reserve a record, but forget to submit (or discard) it.
bpf_ringbuf_query() helper allows to query various properties of ring buffer.
Currently 4 are supported:
- BPF_RB_AVAIL_DATA returns amount of unconsumed data in ring buffer;
- BPF_RB_RING_SIZE returns the size of ring buffer;
- BPF_RB_CONS_POS/BPF_RB_PROD_POS returns current logical possition of
consumer/producer, respectively.
Returned values are momentarily snapshots of ring buffer state and could be
off by the time helper returns, so this should be used only for
debugging/reporting reasons or for implementing various heuristics, that take
into account highly-changeable nature of some of those characteristics.
One such heuristic might involve more fine-grained control over poll/epoll
notifications about new data availability in ring buffer. Together with
BPF_RB_NO_WAKEUP/BPF_RB_FORCE_WAKEUP flags for output/commit/discard helpers,
it allows BPF program a high degree of control and, e.g., more efficient
batched notifications. Default self-balancing strategy, though, should be
adequate for most applications and will work reliable and efficiently already.
Design and implementation
-------------------------
This reserve/commit schema allows a natural way for multiple producers, either
on different CPUs or even on the same CPU/in the same BPF program, to reserve
independent records and work with them without blocking other producers. This
means that if BPF program was interruped by another BPF program sharing the
same ring buffer, they will both get a record reserved (provided there is
enough space left) and can work with it and submit it independently. This
applies to NMI context as well, except that due to using a spinlock during
reservation, in NMI context, bpf_ringbuf_reserve() might fail to get a lock,
in which case reservation will fail even if ring buffer is not full.
The ring buffer itself internally is implemented as a power-of-2 sized
circular buffer, with two logical and ever-increasing counters (which might
wrap around on 32-bit architectures, that's not a problem):
- consumer counter shows up to which logical position consumer consumed the
data;
- producer counter denotes amount of data reserved by all producers.
Each time a record is reserved, producer that "owns" the record will
successfully advance producer counter. At that point, data is still not yet
ready to be consumed, though. Each record has 8 byte header, which contains
the length of reserved record, as well as two extra bits: busy bit to denote
that record is still being worked on, and discard bit, which might be set at
commit time if record is discarded. In the latter case, consumer is supposed
to skip the record and move on to the next one. Record header also encodes
record's relative offset from the beginning of ring buffer data area (in
pages). This allows bpf_ringbuf_commit()/bpf_ringbuf_discard() to accept only
the pointer to the record itself, without requiring also the pointer to ring
buffer itself. Ring buffer memory location will be restored from record
metadata header. This significantly simplifies verifier, as well as improving
API usability.
Producer counter increments are serialized under spinlock, so there is
a strict ordering between reservations. Commits, on the other hand, are
completely lockless and independent. All records become available to consumer
in the order of reservations, but only after all previous records where
already committed. It is thus possible for slow producers to temporarily hold
off submitted records, that were reserved later.
Reservation/commit/consumer protocol is verified by litmus tests in
Documentation/litmus-test/bpf-rb.
One interesting implementation bit, that significantly simplifies (and thus
speeds up as well) implementation of both producers and consumers is how data
area is mapped twice contiguously back-to-back in the virtual memory. This
allows to not take any special measures for samples that have to wrap around
at the end of the circular buffer data area, because the next page after the
last data page would be first data page again, and thus the sample will still
appear completely contiguous in virtual memory. See comment and a simple ASCII
diagram showing this visually in bpf_ringbuf_area_alloc().
Another feature that distinguishes BPF ringbuf from perf ring buffer is
a self-pacing notifications of new data being availability.
bpf_ringbuf_commit() implementation will send a notification of new record
being available after commit only if consumer has already caught up right up
to the record being committed. If not, consumer still has to catch up and thus
will see new data anyways without needing an extra poll notification.
Benchmarks (see tools/testing/selftests/bpf/benchs/bench_ringbuf.c) show that
this allows to achieve a very high throughput without having to resort to
tricks like "notify only every Nth sample", which are necessary with perf
buffer. For extreme cases, when BPF program wants more manual control of
notifications, commit/discard/output helpers accept BPF_RB_NO_WAKEUP and
BPF_RB_FORCE_WAKEUP flags, which give full control over notifications of data
availability, but require extra caution and diligence in using this API.
Comparison to alternatives
--------------------------
Before considering implementing BPF ring buffer from scratch existing
alternatives in kernel were evaluated, but didn't seem to meet the needs. They
largely fell into few categores:
- per-CPU buffers (perf, ftrace, etc), which don't satisfy two motivations
outlined above (ordering and memory consumption);
- linked list-based implementations; while some were multi-producer designs,
consuming these from user-space would be very complicated and most
probably not performant; memory-mapping contiguous piece of memory is
simpler and more performant for user-space consumers;
- io_uring is SPSC, but also requires fixed-sized elements. Naively turning
SPSC queue into MPSC w/ lock would have subpar performance compared to
locked reserve + lockless commit, as with BPF ring buffer. Fixed sized
elements would be too limiting for BPF programs, given existing BPF
programs heavily rely on variable-sized perf buffer already;
- specialized implementations (like a new printk ring buffer, [0]) with lots
of printk-specific limitations and implications, that didn't seem to fit
well for intended use with BPF programs.
[0] https://lwn.net/Articles/779550/
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200529075424.3139988-2-andriin@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
|
||
|
Anton Protopopov
|
43dd115b1f |
selftests/bpf: Add tests for write-only stacks/queues
For write-only stacks and queues bpf_map_update_elem should be allowed, but bpf_map_lookup_elem and bpf_map_lookup_and_delete_elem should fail with EPERM. Signed-off-by: Anton Protopopov <a.s.protopopov@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20200527185700.14658-6-a.s.protopopov@gmail.com Signed-off-by: Alexei Starovoitov <ast@kernel.org> |