Romain Gantois says:
====================
Fix missing PHY-to-MAC RX clock
There is an issue with some stmmac/PHY combinations that has been reported
some time ago in a couple of different series:
Clark Wang's report:
https://lore.kernel.org/all/20230202081559.3553637-1-xiaoning.wang@nxp.com/
Clément Léger's report:
https://lore.kernel.org/linux-arm-kernel/20230116103926.276869-4-clement.leger@bootlin.com/
Stmmac controllers require an RX clock signal from the MII bus to perform
their hardware initialization successfully. This causes issues with some
PHY/PCS devices. If these devices do not bring the clock signal up before
the MAC driver initializes its hardware, then said initialization will
fail. This can happen at probe time or when the system wakes up from a
suspended state.
This series introduces new flags for phy_device and phylink_pcs. These
flags allow MAC drivers to signal to PHY/PCS drivers that the RX clock
signal should be enabled as soon as possible, and that it should always
stay enabled.
I have included specific uses of these flags that fix the RZN1 GMAC1 stmmac
driver that I am currently working on and that is not yet upstream. I have
also included changes to the at803x PHY driver that should fix the issue
that Clark Wang was having.
====================
Link: https://lore.kernel.org/r/20240326-rxc_bugfix-v6-0-24a74e5c761f@bootlin.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Stmmac controllers connected to an at803x PHY cannot resume properly after
suspend when WoL is enabled. This happens because the MAC requires an RX
clock generated by the PHY to initialize its hardware properly. But the RX
clock is cut when the PHY suspends and isn't brought up until the MAC
driver resumes the phylink.
Prevent the at803x PHY driver from going into suspend if the attached MAC
driver always requires an RX clock signal.
Reported-by: Clark Wang <xiaoning.wang@nxp.com>
Link: https://lore.kernel.org/all/20230202081559.3553637-1-xiaoning.wang@nxp.com/
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
[rgantois: commit log]
Signed-off-by: Romain Gantois <romain.gantois@bootlin.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lore.kernel.org/r/20240326-rxc_bugfix-v6-6-24a74e5c761f@bootlin.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
There is a reocurring issue with stmmac controllers where the MAC fails to
initialize its hardware if an RX clock signal isn't provided on the MAC/PHY
link.
This causes issues when PHY or PCS devices either go into suspend while
cutting the RX clock or do not bring the clock signal up early enough for
the MAC to initialize successfully.
Set the mac_requires_rxc flag in the stmmac phylink config so that PHY/PCS
drivers know to keep the RX clock up at all times.
Reported-by: Clark Wang <xiaoning.wang@nxp.com>
Link: https://lore.kernel.org/all/20230202081559.3553637-1-xiaoning.wang@nxp.com/
Reported-by: Clément Léger <clement.leger@bootlin.com>
Link: https://lore.kernel.org/linux-arm-kernel/20230116103926.276869-4-clement.leger@bootlin.com/
Co-developed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Romain Gantois <romain.gantois@bootlin.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lore.kernel.org/r/20240326-rxc_bugfix-v6-5-24a74e5c761f@bootlin.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Global stmmac support for early initialization of PCS devices requires a
generic PCS reference that can be passed to phylink_pcs_pre_init().
Currently, the mac_device_info struct contains only one PCS field, which is
specific to the Lynx model.
As PCS models are hardware-specific, it is more appropriate to have a
generic PCS field in the mac_device_info struct.
Refactor the lynx_pcs field into a generic phylink_pcs field.
Signed-off-by: Romain Gantois <romain.gantois@bootlin.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lore.kernel.org/r/20240326-rxc_bugfix-v6-4-24a74e5c761f@bootlin.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
When initializing attached PHYs, there are some cases where we don't expect
any PHY to be connected. The logic uses conditions based on various local
PCS configuration, but also calls-in phylink_expects_phy() via
stmmac_init_phy(), which is enough to ensure we don't try to initialize a
PHY when using a Lynx PCS, as long as we have the phy_interface set to a
802.3z mode and are using inband negociation.
Drop the lynx check, making the stmmac generic code more pcs_lynx-agnostic.
Signed-off-by: Maxime Chevallier <maxime.chevallier@bootlin.com>
[rgantois: commit log]
Signed-off-by: Romain Gantois <romain.gantois@bootlin.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lore.kernel.org/r/20240326-rxc_bugfix-v6-3-24a74e5c761f@bootlin.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Some MAC drivers (e.g. stmmac) require a continuous receive clock signal to
be generated by a PCS that is handled by a standalone PCS driver.
Such a PCS driver does not have access to a PHY device, thus cannot check
the PHY_F_RXC_ALWAYS_ON flag. They cannot check max_requires_rxc in the
phylink config either, since it is a private member. Therefore, a new flag
is needed to signal to the PCS that it should keep the RX clock signal up
at all times.
Co-developed-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Signed-off-by: Romain Gantois <romain.gantois@bootlin.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lore.kernel.org/r/20240326-rxc_bugfix-v6-2-24a74e5c761f@bootlin.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Some MAC controllers (e.g. stmmac) require their connected PHY to
continuously provide a receive clock signal. This can cause issues in two
cases:
1. The clock signal hasn't been started yet by the time the MAC driver
initializes its hardware. This can make the initialization fail, as in
the case of the rzn1 GMAC1 driver.
2. The clock signal is cut during a power saving event. By the time the
MAC is brought back up, the clock signal is still not active since
phylink_start hasn't been called yet. This brings us back to case 1.
If a PHY driver reads this flag, it should ensure that the receive clock
signal is started as soon as possible, and that it isn't brought down when
the PHY goes into suspend.
Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
[rgantois: commit log]
Signed-off-by: Romain Gantois <romain.gantois@bootlin.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Link: https://lore.kernel.org/r/20240326-rxc_bugfix-v6-1-24a74e5c761f@bootlin.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Geliang Tang says:
====================
Simplify bpf_tcp_ca test by using connect_fd_to_fd and start_server
helpers.
v4:
- Matt reminded me that I shouldn't send a square-to patch to BPF (thanks),
so I update them into two patches in v4.
v3:
- split v2 as two patches as Daniel suggested.
- The patch "selftests/bpf: Use start_server in bpf_tcp_ca" is merged
by Daniel (thanks), but I forgot to drop 'settimeo(lfd, 0)' in it, so
I send a squash-to patch to fix this.
====================
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
To simplify the code, use BPF selftests helper connect_fd_to_fd() in
bpf_tcp_ca.c instead of open-coding it. This helper is defined in
network_helpers.c, and exported in network_helpers.h, which is already
included in bpf_tcp_ca.c.
Signed-off-by: Geliang Tang <tanggeliang@kylinos.cn>
Link: https://lore.kernel.org/r/e105d1f225c643bee838409378dd90fd9aabb6dc.1711447102.git.tanggeliang@kylinos.cn
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Tony Nguyen says:
====================
Intel Wired LAN Driver Updates 2024-03-27 (e1000e)
This series contains updates to e1000e driver only.
Vitaly adds retry mechanism for some PHY operations to workaround MDI
error and moves SMBus configuration to avoid possible PHY loss.
* '1GbE' of git://git.kernel.org/pub/scm/linux/kernel/git/tnguy/net-queue:
e1000e: move force SMBUS from enable ulp function to avoid PHY loss issue
e1000e: Workaround for sporadic MDI error on Meteor Lake systems
====================
Link: https://lore.kernel.org/r/20240327185517.2587564-1-anthony.l.nguyen@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Alexander Lobakin says:
====================
compiler_types: add Endianness-dependent __counted_by_{le,be}
Some structures contain flexible arrays at the end and the counter for
them, but the counter has explicit Endianness and thus __counted_by()
can't be used directly.
To increase test coverage for potential problems without breaking
anything, introduce __counted_by_{le,be} defined depending on platform's
Endianness to either __counted_by() when applicable or noop otherwise.
The first user will be virtchnl2.h from idpf just as example with 9 flex
structures having Little Endian counters.
Maybe it would be a good idea to introduce such attributes on compiler
level if possible, but for now let's stop on what we have.
====================
Link: https://lore.kernel.org/r/20240327142241.1745989-1-aleksander.lobakin@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Both virtchnl2.h and its consumer idpf_virtchnl.c are very error-prone.
There are 10 structures with flexible arrays at the end, but 9 of them
has flex member counter in Little Endian.
Make the code a bit more robust by applying __counted_by_le() to those
9. LE platforms is the main target for this driver, so they would
receive additional protection.
While we're here, add __counted_by() to virtchnl2_ptype::proto_id, as
its counter is `u8` regardless of the Endianness.
Compile test on x86_64 (LE) didn't reveal any new issues after applying
the attributes.
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Link: https://lore.kernel.org/r/20240327142241.1745989-4-aleksander.lobakin@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
To ease maintaining of virtchnl2.h, which already is messy enough,
make it self-contained by adding missing if_ether.h include due to
%ETH_ALEN usage.
At the same time, virtchnl2_lan_desc.h is not used anywhere in the
file, so move this include to idpf_txrx.h to speed up C preprocessing.
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Link: https://lore.kernel.org/r/20240327142241.1745989-3-aleksander.lobakin@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Some structures contain flexible arrays at the end and the counter for
them, but the counter has explicit Endianness and thus __counted_by()
can't be used directly.
To increase test coverage for potential problems without breaking
anything, introduce __counted_by_{le,be}() defined depending on
platform's Endianness to either __counted_by() when applicable or noop
otherwise.
Maybe it would be a good idea to introduce such attributes on compiler
level if possible, but for now let's stop on what we have.
Acked-by: Kees Cook <keescook@chromium.org>
Acked-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Alexander Lobakin <aleksander.lobakin@intel.com>
Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Link: https://lore.kernel.org/r/20240327142241.1745989-2-aleksander.lobakin@intel.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
BPF link for some program types is passed as a "context" which can be
used by those BPF programs to look up additional information. E.g., for
multi-kprobes and multi-uprobes, link is used to fetch BPF cookie values.
Because of this runtime dependency, when bpf_link refcnt drops to zero
there could still be active BPF programs running accessing link data.
This patch adds generic support to defer bpf_link dealloc callback to
after RCU GP, if requested. This is done by exposing two different
deallocation callbacks, one synchronous and one deferred. If deferred
one is provided, bpf_link_free() will schedule dealloc_deferred()
callback to happen after RCU GP.
BPF is using two flavors of RCU: "classic" non-sleepable one and RCU
tasks trace one. The latter is used when sleepable BPF programs are
used. bpf_link_free() accommodates that by checking underlying BPF
program's sleepable flag, and goes either through normal RCU GP only for
non-sleepable, or through RCU tasks trace GP *and* then normal RCU GP
(taking into account rcu_trace_implies_rcu_gp() optimization), if BPF
program is sleepable.
We use this for multi-kprobe and multi-uprobe links, which dereference
link during program run. We also preventively switch raw_tp link to use
deferred dealloc callback, as upcoming changes in bpf-next tree expose
raw_tp link data (specifically, cookie value) to BPF program at runtime
as well.
Fixes: 0dcac27254 ("bpf: Add multi kprobe link")
Fixes: 89ae89f53d ("bpf: Add multi uprobe link")
Reported-by: syzbot+981935d9485a560bfbcb@syzkaller.appspotmail.com
Reported-by: syzbot+2cb5a6c573e98db598cc@syzkaller.appspotmail.com
Reported-by: syzbot+62d8b26793e8a2bd0516@syzkaller.appspotmail.com
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Link: https://lore.kernel.org/r/20240328052426.3042617-2-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
There is no need to delay putting either path or task to deallocation
step. It can be done right after bpf_uprobe_unregister. Between release
and dealloc, there could be still some running BPF programs, but they
don't access either task or path, only data in link->uprobes, so it is
safe to do.
On the other hand, doing path_put() in dealloc callback makes this
dealloc sleepable because path_put() itself might sleep. Which is
problematic due to the need to call uprobe's dealloc through call_rcu(),
which is what is done in the next bug fix patch. So solve the problem by
releasing these resources early.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240328052426.3042617-1-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Merge series from Louis Chauvet <louis.chauvet@bootlin.com>:
This series adds the support for the omap-mcspi multi mode which allows
sending SPI messages with a shorter delay between CS and the message.
One drawback of the multi-mode is that the CS is raised between each word,
so it can only be used with messages containing 1 word transfers and
asking for cs_change. Few devices, like FPGAs, may easily workaround this
limitation.
The first patch removes the current implementation, which is working, but
don't comply with what is asked in the spi transfer (The CS is raised by
the hardware regardless of cs_change state). No drivers or board file use this
implementation upstream.
The second patch adds the implementation of the multi-mode, which complies
with what is asked in the SPI message.
The third patch is the suggested optimization for using MULTI mode in more
situations.
Merge series from Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>:
This last part is the continuation of Brent Lu's cleanups. Multiple
quirks have been removed to use "default" configurations and
ACPI-based detection of codecs and selection of topology files.
This cleanup has been done in multiple steps/phases since Fall 2023,
thanks Brent for this contribution!
Yonghong Song says:
====================
bpf: Fix a couple of test failures with LTO kernel
With a LTO kernel built with clang, with one of earlier version of kernel,
I encountered two test failures, ksyms and kprobe_multi_bench_attach/kernel.
Now with latest bpf-next, only kprobe_multi_bench_attach/kernel failed.
But it is possible in the future ksyms selftest may fail again.
Both test failures are due to static variable/function renaming
due to cross-file inlining. For Ksyms failure, the solution is
to strip .llvm.<hash> suffixes for symbols in /proc/kallsyms before
comparing against the ksym in bpf program.
For kprobe_multi_bench_attach/kernel failure, the solution is
to either provide names in /proc/kallsyms to the kernel or
ignore those names who have .llvm.<hash> suffix since the kernel
sym name comparison is against /proc/kallsyms.
Please see each individual patches for details.
Changelogs:
v2 -> v3:
- no need to check config file, directly so strstr with '.llvm.'.
- for kprobe_multi_bench with syms, instead of skipping the syms,
consult /proc/kallyms to find corresponding names.
- add a test with populating addrs to the kernel for kprobe
multi attach.
v1 -> v2:
- Let libbpf handle .llvm.<hash suffixes since it may impact
bpf program ksym.
====================
Link: https://lore.kernel.org/r/20240326041443.1197498-1-yonghong.song@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Get addrs directly from available_filter_functions_addrs and
send to the kernel during kprobe_multi_attach. This avoids
consultation of /proc/kallsyms. But available_filter_functions_addrs
is introduced in 6.5, i.e., it is introduced recently,
so I skip the test if the kernel does not support it.
Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20240326041523.1200301-1-yonghong.song@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
In my locally build clang LTO kernel (enabling CONFIG_LTO and
CONFIG_LTO_CLANG_THIN), kprobe_multi_bench_attach/kernel subtest
failed like:
test_kprobe_multi_bench_attach:PASS:get_syms 0 nsec
test_kprobe_multi_bench_attach:PASS:kprobe_multi_empty__open_and_load 0 nsec
libbpf: prog 'test_kprobe_empty': failed to attach: No such process
test_kprobe_multi_bench_attach:FAIL:bpf_program__attach_kprobe_multi_opts unexpected error: -3
#117/1 kprobe_multi_bench_attach/kernel:FAIL
There are multiple symbols in /sys/kernel/debug/tracing/available_filter_functions
are renamed in /proc/kallsyms due to cross file inlining. One example is for
static function __access_remote_vm in mm/memory.c.
In a non-LTO kernel, we have the following call stack:
ptrace_access_vm (global, kernel/ptrace.c)
access_remote_vm (global, mm/memory.c)
__access_remote_vm (static, mm/memory.c)
With LTO kernel, it is possible that access_remote_vm() is inlined by
ptrace_access_vm(). So we end up with the following call stack:
ptrace_access_vm (global, kernel/ptrace.c)
__access_remote_vm (static, mm/memory.c)
The compiler renames __access_remote_vm to __access_remote_vm.llvm.<hash>
to prevent potential name collision.
The kernel bpf_kprobe_multi_link_attach() and ftrace_lookup_symbols() try
to find addresses based on /proc/kallsyms, hence the current test failed
with LTO kenrel.
This patch consulted /proc/kallsyms to find the corresponding entries
for the ksym and this solved the issue.
Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20240326041518.1199758-1-yonghong.song@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
These two functions allow selftests to do loading/searching
kallsyms based on their specific compare functions.
Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20240326041513.1199440-1-yonghong.song@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Refactor trace helper function load_kallsyms_local() such that
it invokes a common function with a compare function as input.
The common function will be used later for other local functions.
Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20240326041508.1199239-1-yonghong.song@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Refactor some functions in kprobe_multi_test.c to extract
some helper functions who will be used in later patches
to avoid code duplication.
Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20240326041503.1198982-1-yonghong.song@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
With CONFIG_LTO_CLANG_THIN enabled, with some of previous
version of kernel code base ([1]), I hit the following
error:
test_ksyms:PASS:kallsyms_fopen 0 nsec
test_ksyms:FAIL:ksym_find symbol 'bpf_link_fops' not found
#118 ksyms:FAIL
The reason is that 'bpf_link_fops' is renamed to
bpf_link_fops.llvm.8325593422554671469
Due to cross-file inlining, the static variable 'bpf_link_fops'
in syscall.c is used by a function in another file. To avoid
potential duplicated names, the llvm added suffix
'.llvm.<hash>' ([2]) to 'bpf_link_fops' variable.
Such renaming caused a problem in libbpf if 'bpf_link_fops'
is used in bpf prog as a ksym but 'bpf_link_fops' does not
match any symbol in /proc/kallsyms.
To fix this issue, libbpf needs to understand that suffix '.llvm.<hash>'
is caused by clang lto kernel and to process such symbols properly.
With latest bpf-next code base built with CONFIG_LTO_CLANG_THIN,
I cannot reproduce the above failure any more. But such an issue
could happen with other symbols or in the future for bpf_link_fops symbol.
For example, with my current kernel, I got the following from
/proc/kallsyms:
ffffffff84782154 d __func__.net_ratelimit.llvm.6135436931166841955
ffffffff85f0a500 d tk_core.llvm.726630847145216431
ffffffff85fdb960 d __fs_reclaim_map.llvm.10487989720912350772
ffffffff864c7300 d fake_dst_ops.llvm.54750082607048300
I could not easily create a selftest to test newly-added
libbpf functionality with a static C test since I do not know
which symbol is cross-file inlined. But based on my particular kernel,
the following test change can run successfully.
> diff --git a/tools/testing/selftests/bpf/prog_tests/ksyms.c b/tools/testing/selftests/bpf/prog_tests/ksyms.c
> index 6a86d1f07800..904a103f7b1d 100644
> --- a/tools/testing/selftests/bpf/prog_tests/ksyms.c
> +++ b/tools/testing/selftests/bpf/prog_tests/ksyms.c
> @@ -42,6 +42,7 @@ void test_ksyms(void)
> ASSERT_EQ(data->out__bpf_link_fops, link_fops_addr, "bpf_link_fops");
> ASSERT_EQ(data->out__bpf_link_fops1, 0, "bpf_link_fops1");
> ASSERT_EQ(data->out__btf_size, btf_size, "btf_size");
> + ASSERT_NEQ(data->out__fake_dst_ops, 0, "fake_dst_ops");
> ASSERT_EQ(data->out__per_cpu_start, per_cpu_start_addr, "__per_cpu_start");
>
> cleanup:
> diff --git a/tools/testing/selftests/bpf/progs/test_ksyms.c b/tools/testing/selftests/bpf/progs/test_ksyms.c
> index 6c9cbb5a3bdf..fe91eef54b66 100644
> --- a/tools/testing/selftests/bpf/progs/test_ksyms.c
> +++ b/tools/testing/selftests/bpf/progs/test_ksyms.c
> @@ -9,11 +9,13 @@ __u64 out__bpf_link_fops = -1;
> __u64 out__bpf_link_fops1 = -1;
> __u64 out__btf_size = -1;
> __u64 out__per_cpu_start = -1;
> +__u64 out__fake_dst_ops = -1;
>
> extern const void bpf_link_fops __ksym;
> extern const void __start_BTF __ksym;
> extern const void __stop_BTF __ksym;
> extern const void __per_cpu_start __ksym;
> +extern const void fake_dst_ops __ksym;
> /* non-existing symbol, weak, default to zero */
> extern const void bpf_link_fops1 __ksym __weak;
>
> @@ -23,6 +25,7 @@ int handler(const void *ctx)
> out__bpf_link_fops = (__u64)&bpf_link_fops;
> out__btf_size = (__u64)(&__stop_BTF - &__start_BTF);
> out__per_cpu_start = (__u64)&__per_cpu_start;
> + out__fake_dst_ops = (__u64)&fake_dst_ops;
>
> out__bpf_link_fops1 = (__u64)&bpf_link_fops1;
This patch fixed the issue in libbpf such that
the suffix '.llvm.<hash>' will be ignored during comparison of
bpf prog ksym vs. symbols in /proc/kallsyms, this resolved the issue.
Currently, only static variables in /proc/kallsyms are checked
with '.llvm.<hash>' suffix since in bpf programs function ksyms
with '.llvm.<hash>' suffix are most likely kfunc's and unlikely
to be cross-file inlined.
Note that currently kernel does not support gcc build with lto.
[1] https://lore.kernel.org/bpf/20240302165017.1627295-1-yonghong.song@linux.dev/
[2] https://github.com/llvm/llvm-project/blob/release/18.x/llvm/include/llvm/IR/ModuleSummaryIndex.h#L1714-L1719
Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20240326041458.1198161-1-yonghong.song@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Currently libbpf_kallsyms_parse() function is declared as a global
function but actually it is not a API and there is no external
users in bpftool/bpf-selftests. So let us mark the function as
static.
Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20240326041453.1197949-1-yonghong.song@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Replace CHECK with ASSERT macros for ksyms tests.
This test failed earlier with clang lto kernel, but the
issue is gone with latest code base. But replacing
CHECK with ASSERT still improves code as ASSERT is
preferred in selftests.
Signed-off-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20240326041448.1197812-1-yonghong.song@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Merge series from Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>:
Core for several drivers already sets the driver.owner, so driver does
not need to. Simplify the drivers.
This patch adds a test to ensure all static tcp-cc kfuncs is visible to
the struct_ops bpf programs. It is checked by successfully loading
the struct_ops programs calling these tcp-cc kfuncs.
This patch needs to enable the CONFIG_TCP_CONG_DCTCP and
the CONFIG_TCP_CONG_BBR.
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20240322191433.4133280-2-martin.lau@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The commit 7aae231ac9 ("bpf: tcp: Limit calling some tcp cc functions to CONFIG_DYNAMIC_FTRACE")
added CONFIG_DYNAMIC_FTRACE guard because pahole was only generating
btf for ftrace-able functions. The ftrace filter had already been
removed from pahole, so the CONFIG_DYNAMIC_FTRACE guard can be
removed.
The commit 569c484f99 ("bpf: Limit static tcp-cc functions in the .BTF_ids list to x86")
has added CONFIG_X86 guard because it failed the powerpc arch which
prepended a "." to the local static function, so "cubictcp_init" becomes
".cubictcp_init". "__bpf_kfunc" has been added to kfunc
since then and it uses the __unused compiler attribute.
There is an existing
"__bpf_kfunc static u32 bpf_kfunc_call_test_static_unused_arg(u32 arg, u32 unused)"
test in bpf_testmod.c to cover the static kfunc case.
cross compile on ppc64 with CONFIG_DYNAMIC_FTRACE disabled:
> readelf -s vmlinux | grep cubictcp_
56938: c00000000144fd00 184 FUNC LOCAL DEFAULT 2 cubictcp_cwnd_event [<localentry>: 8]
56939: c00000000144fdb8 200 FUNC LOCAL DEFAULT 2 cubictcp_recalc_[...] [<localentry>: 8]
56940: c00000000144fe80 296 FUNC LOCAL DEFAULT 2 cubictcp_init [<localentry>: 8]
56941: c00000000144ffa8 228 FUNC LOCAL DEFAULT 2 cubictcp_state [<localentry>: 8]
56942: c00000000145008c 1908 FUNC LOCAL DEFAULT 2 cubictcp_cong_avoid [<localentry>: 8]
56943: c000000001450800 1644 FUNC LOCAL DEFAULT 2 cubictcp_acked [<localentry>: 8]
> bpftool btf dump file vmlinux | grep cubictcp_
[51540] FUNC 'cubictcp_acked' type_id=38137 linkage=static
[51541] FUNC 'cubictcp_cong_avoid' type_id=38122 linkage=static
[51543] FUNC 'cubictcp_cwnd_event' type_id=51542 linkage=static
[51544] FUNC 'cubictcp_init' type_id=9186 linkage=static
[51545] FUNC 'cubictcp_recalc_ssthresh' type_id=35021 linkage=static
[51547] FUNC 'cubictcp_state' type_id=38141 linkage=static
The patch removed both config guards.
Cc: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Link: https://lore.kernel.org/r/20240322191433.4133280-1-martin.lau@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Following the recent upgrade of one of our BPF programs, we encountered
significant latency spikes affecting other applications running on the same
host. After thorough investigation, we identified that these spikes were
primarily caused by the prolonged duration required to free a
non-preallocated htab with approximately 2 million keys.
Notably, our kernel configuration lacks the presence of CONFIG_PREEMPT. In
scenarios where kernel execution extends excessively, other threads might
be starved of CPU time, resulting in latency issues across the system. To
mitigate this, we've adopted a proactive approach by incorporating
cond_resched() calls within the kernel code. This ensures that during
lengthy kernel operations, the scheduler is invoked periodically to provide
opportunities for other threads to execute.
Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20240327032022.78391-1-laoar.shao@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Andrii Nakryiko says:
====================
bench: fast in-kernel triggering benchmarks
Remove "legacy" triggering benchmarks which rely on syscalls (and thus syscall
overhead is a noticeable part of benchmark, unfortunately). Replace them with
faster versions that rely on triggering BPF programs in-kernel through another
simple "driver" BPF program. See patch #2 with comparison results.
raw_tp/tp/fmodret benchmarks required adding a simple kfunc in kernel to be
able to trigger a simple tracepoint from BPF program (plus it is also allowed
to be replaced by fmod_ret programs). This limits raw_tp/tp/fmodret benchmarks
to new kernels only, but it keeps bench tool itself very portable and most of
other benchmarks will still work on wide variety of kernels without the need
to worry about building and deploying custom kernel module. See patches #5
and #6 for details.
v1->v2:
- move new TP closer to BPF test run code;
- rename/move kfunc and register it for fmod_rets (Alexei);
- limit --trig-batch-iters param to [1, 1000] (Alexei).
====================
Link: https://lore.kernel.org/r/20240326162151.3981687-1-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Utilize bpf_modify_return_test_tp() kfunc to have a fast way to trigger
tp/raw_tp/fmodret programs from another BPF program, which gives us
comparable batched benchmarks to (batched) kprobe/fentry benchmarks.
We don't switch kprobe/fentry batched benchmarks to this kfunc to make
bench tool usable on older kernels as well.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240326162151.3981687-7-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Add a simple bpf_modify_return_test_tp() kfunc, available to all program
types, that is useful for various testing and benchmarking scenarios, as
it allows to trigger most tracing BPF program types from BPF side,
allowing to do complex testing and benchmarking scenarios.
It is also attachable to for fmod_ret programs, making it a good and
simple way to trigger fmod_ret program under test/benchmark.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240326162151.3981687-6-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Instead of front-loading all possible benchmarking BPF programs for
trigger benchmarks, explicitly specify which BPF programs are used by
specific benchmark and load only it.
This allows to be more flexible in supporting older kernels, where some
program types might not be possible to load (e.g., those that rely on
newly added kfunc).
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240326162151.3981687-5-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Remove "legacy" benchmarks triggered by syscalls in favor of newly added
in-kernel/batched benchmarks. Drop -batched suffix now as well.
Next patch will restore "feature parity" by adding back
tp/raw_tp/fmodret benchmarks based on in-kernel kfunc approach.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240326162151.3981687-4-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Existing kprobe/fentry triggering benchmarks have 1-to-1 mapping between
one syscall execution and BPF program run. While we use a fast
get_pgid() syscall, syscall overhead can still be non-trivial.
This patch adds kprobe/fentry set of benchmarks significantly amortizing
the cost of syscall vs actual BPF triggering overhead. We do this by
employing BPF_PROG_TEST_RUN command to trigger "driver" raw_tp program
which does a tight parameterized loop calling cheap BPF helper
(bpf_get_numa_node_id()), to which kprobe/fentry programs are
attached for benchmarking.
This way 1 bpf() syscall causes N executions of BPF program being
benchmarked. N defaults to 100, but can be adjusted with
--trig-batch-iters CLI argument.
For comparison we also implement a new baseline program that instead of
triggering another BPF program just does N atomic per-CPU counter
increments, establishing the limit for all other types of program within
this batched benchmarking setup.
Taking the final set of benchmarks added in this patch set (including
tp/raw_tp/fmodret, added in later patch), and keeping for now "legacy"
syscall-driven benchmarks, we can capture all triggering benchmarks in
one place for comparison, before we remove the legacy ones (and rename
xxx-batched into just xxx).
$ benchs/run_bench_trigger.sh
usermode-count : 79.500 ± 0.024M/s
kernel-count : 49.949 ± 0.081M/s
syscall-count : 9.009 ± 0.007M/s
fentry-batch : 31.002 ± 0.015M/s
fexit-batch : 20.372 ± 0.028M/s
fmodret-batch : 21.651 ± 0.659M/s
rawtp-batch : 36.775 ± 0.264M/s
tp-batch : 19.411 ± 0.248M/s
kprobe-batch : 12.949 ± 0.220M/s
kprobe-multi-batch : 15.400 ± 0.007M/s
kretprobe-batch : 5.559 ± 0.011M/s
kretprobe-multi-batch: 5.861 ± 0.003M/s
fentry-legacy : 8.329 ± 0.004M/s
fexit-legacy : 6.239 ± 0.003M/s
fmodret-legacy : 6.595 ± 0.001M/s
rawtp-legacy : 8.305 ± 0.004M/s
tp-legacy : 6.382 ± 0.001M/s
kprobe-legacy : 5.528 ± 0.003M/s
kprobe-multi-legacy : 5.864 ± 0.022M/s
kretprobe-legacy : 3.081 ± 0.001M/s
kretprobe-multi-legacy: 3.193 ± 0.001M/s
Note how xxx-batch variants are measured with significantly higher
throughput, even though it's exactly the same in-kernel overhead. As
such, results can be compared only between benchmarks of the same kind
(syscall vs batched):
fentry-legacy : 8.329 ± 0.004M/s
fentry-batch : 31.002 ± 0.015M/s
kprobe-multi-legacy : 5.864 ± 0.022M/s
kprobe-multi-batch : 15.400 ± 0.007M/s
Note also that syscall-count is setting a theoretical limit for
syscall-triggered benchmarks, while kernel-count is setting similar
limits for batch variants. usermode-count is a happy and unachievable
case of user space counting without doing any syscalls, and is mostly
the measure of CPU speed for such a trivial benchmark.
As was mentioned, tp/raw_tp/fmodret require kernel-side kfunc to produce
similar benchmark, which we address in a separate patch.
Note that run_bench_trigger.sh allows to override a list of benchmarks
to run, which is very useful for performance work.
Cc: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240326162151.3981687-3-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Rename uprobe-base to more precise usermode-count (it will match other
baseline-like benchmarks, kernel-count and syscall-count). Also use
BENCH_TRIG_USERMODE() macro to define all usermode-based triggering
benchmarks, which include usermode-count and uprobe/uretprobe benchmarks.
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/r/20240326162151.3981687-2-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Use the well defined helper sizeof_field() to calculate the size of a
struct member, instead of doing custom calculations.
Signed-off-by: Haiyue Wang <haiyue.wang@intel.com>
Link: https://lore.kernel.org/r/20240327065334.8140-1-haiyue.wang@intel.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Merge series from Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>:
Fix a set of problematic locking sequences and update error messages,
tested on SOF/SoundWire platforms.
