Pull networking updates from David Millar:
"Here are some highlights from the 2065 networking commits that
happened this development cycle:
1) XDP support for IXGBE (John Fastabend) and thunderx (Sunil Kowuri)
2) Add a generic XDP driver, so that anyone can test XDP even if they
lack a networking device whose driver has explicit XDP support
(me).
3) Sparc64 now has an eBPF JIT too (me)
4) Add a BPF program testing framework via BPF_PROG_TEST_RUN (Alexei
Starovoitov)
5) Make netfitler network namespace teardown less expensive (Florian
Westphal)
6) Add symmetric hashing support to nft_hash (Laura Garcia Liebana)
7) Implement NAPI and GRO in netvsc driver (Stephen Hemminger)
8) Support TC flower offload statistics in mlxsw (Arkadi Sharshevsky)
9) Multiqueue support in stmmac driver (Joao Pinto)
10) Remove TCP timewait recycling, it never really could possibly work
well in the real world and timestamp randomization really zaps any
hint of usability this feature had (Soheil Hassas Yeganeh)
11) Support level3 vs level4 ECMP route hashing in ipv4 (Nikolay
Aleksandrov)
12) Add socket busy poll support to epoll (Sridhar Samudrala)
13) Netlink extended ACK support (Johannes Berg, Pablo Neira Ayuso,
and several others)
14) IPSEC hw offload infrastructure (Steffen Klassert)"
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (2065 commits)
tipc: refactor function tipc_sk_recv_stream()
tipc: refactor function tipc_sk_recvmsg()
net: thunderx: Optimize page recycling for XDP
net: thunderx: Support for XDP header adjustment
net: thunderx: Add support for XDP_TX
net: thunderx: Add support for XDP_DROP
net: thunderx: Add basic XDP support
net: thunderx: Cleanup receive buffer allocation
net: thunderx: Optimize CQE_TX handling
net: thunderx: Optimize RBDR descriptor handling
net: thunderx: Support for page recycling
ipx: call ipxitf_put() in ioctl error path
net: sched: add helpers to handle extended actions
qed*: Fix issues in the ptp filter config implementation.
qede: Fix concurrency issue in PTP Tx path processing.
stmmac: Add support for SIMATIC IOT2000 platform
net: hns: fix ethtool_get_strings overflow in hns driver
tcp: fix wraparound issue in tcp_lp
bpf, arm64: fix jit branch offset related to ldimm64
bpf, arm64: implement jiting of BPF_XADD
...
More stuff that came from git, out of the hodge-podge that is util.h
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-e3lana4gctz3ub4hn4y29hkw@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
expose bpf_program__set_type() to set program type
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
add support for BPF_PROG_TEST_RUN command to libbpf.a
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Wang Nan <wangnan0@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Test cases for array of maps and hash of maps.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Will be used in a upcoming patch warning about PERF_RECORD_AUX data
gaps, reading the "module/kvm_intel/parameters/vmm_exclusive" sysfs
entry.
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Cc: Vince Weaver <vince@deater.net>
Link: http://lkml.kernel.org/r/8760j941ig.fsf@ashishki-desk.ger.corp.intel.com
[ split from a larger patch ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fix typos and add the following to the scripts/spelling.txt:
overide||override
While we are here, fix the doubled "address" in the touched line
Documentation/devicetree/bindings/regulator/ti-abb-regulator.txt.
Also, fix the comment block style in the touched hunks in
drivers/media/dvb-frontends/drx39xyj/drx_driver.h.
Link: http://lkml.kernel.org/r/1481573103-11329-21-git-send-email-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix typos and add the following to the scripts/spelling.txt:
overrided||overridden
Link: http://lkml.kernel.org/r/1481573103-11329-22-git-send-email-yamada.masahiro@socionext.com
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This saves 32 bytes on my x86-64 build, mostly due to alignment
considerations and sharing more code between find_next_bit and
find_next_zero_bit, but it does save a couple of instructions.
There's really two parts to this commit:
- First, the first half of the test: (!nbits || start >= nbits) is
trivially a subset of the second half, since nbits and start are both
unsigned
- Second, while looking at the disassembly, I noticed that GCC was
predicting the branch taken. Since this is a failure case, it's
clearly the less likely of the two branches, so add an unlikely() to
override GCC's heuristics.
[mawilcox@microsoft.com: v2]
Link: http://lkml.kernel.org/r/1483709016-1834-1-git-send-email-mawilcox@linuxonhyperv.com
Link: http://lkml.kernel.org/r/1483709016-1834-1-git-send-email-mawilcox@linuxonhyperv.com
Signed-off-by: Matthew Wilcox <mawilcox@microsoft.com>
Acked-by: Yury Norov <ynorov@caviumnetworks.com>
Acked-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull networking updates from David Miller:
"Highlights:
1) Support TX_RING in AF_PACKET TPACKET_V3 mode, from Sowmini
Varadhan.
2) Simplify classifier state on sk_buff in order to shrink it a bit.
From Willem de Bruijn.
3) Introduce SIPHASH and it's usage for secure sequence numbers and
syncookies. From Jason A. Donenfeld.
4) Reduce CPU usage for ICMP replies we are going to limit or
suppress, from Jesper Dangaard Brouer.
5) Introduce Shared Memory Communications socket layer, from Ursula
Braun.
6) Add RACK loss detection and allow it to actually trigger fast
recovery instead of just assisting after other algorithms have
triggered it. From Yuchung Cheng.
7) Add xmit_more and BQL support to mvneta driver, from Simon Guinot.
8) skb_cow_data avoidance in esp4 and esp6, from Steffen Klassert.
9) Export MPLS packet stats via netlink, from Robert Shearman.
10) Significantly improve inet port bind conflict handling, especially
when an application is restarted and changes it's setting of
reuseport. From Josef Bacik.
11) Implement TX batching in vhost_net, from Jason Wang.
12) Extend the dummy device so that VF (virtual function) features,
such as configuration, can be more easily tested. From Phil
Sutter.
13) Avoid two atomic ops per page on x86 in bnx2x driver, from Eric
Dumazet.
14) Add new bpf MAP, implementing a longest prefix match trie. From
Daniel Mack.
15) Packet sample offloading support in mlxsw driver, from Yotam Gigi.
16) Add new aquantia driver, from David VomLehn.
17) Add bpf tracepoints, from Daniel Borkmann.
18) Add support for port mirroring to b53 and bcm_sf2 drivers, from
Florian Fainelli.
19) Remove custom busy polling in many drivers, it is done in the core
networking since 4.5 times. From Eric Dumazet.
20) Support XDP adjust_head in virtio_net, from John Fastabend.
21) Fix several major holes in neighbour entry confirmation, from
Julian Anastasov.
22) Add XDP support to bnxt_en driver, from Michael Chan.
23) VXLAN offloads for enic driver, from Govindarajulu Varadarajan.
24) Add IPVTAP driver (IP-VLAN based tap driver) from Sainath Grandhi.
25) Support GRO in IPSEC protocols, from Steffen Klassert"
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1764 commits)
Revert "ath10k: Search SMBIOS for OEM board file extension"
net: socket: fix recvmmsg not returning error from sock_error
bnxt_en: use eth_hw_addr_random()
bpf: fix unlocking of jited image when module ronx not set
arch: add ARCH_HAS_SET_MEMORY config
net: napi_watchdog() can use napi_schedule_irqoff()
tcp: Revert "tcp: tcp_probe: use spin_lock_bh()"
net/hsr: use eth_hw_addr_random()
net: mvpp2: enable building on 64-bit platforms
net: mvpp2: switch to build_skb() in the RX path
net: mvpp2: simplify MVPP2_PRS_RI_* definitions
net: mvpp2: fix indentation of MVPP2_EXT_GLOBAL_CTRL_DEFAULT
net: mvpp2: remove unused register definitions
net: mvpp2: simplify mvpp2_bm_bufs_add()
net: mvpp2: drop useless fields in mvpp2_bm_pool and related code
net: mvpp2: remove unused 'tx_skb' field of 'struct mvpp2_tx_queue'
net: mvpp2: release reference to txq_cpu[] entry after unmapping
net: mvpp2: handle too large value in mvpp2_rx_time_coal_set()
net: mvpp2: handle too large value handling in mvpp2_rx_pkts_coal_set()
net: mvpp2: remove useless arguments in mvpp2_rx_{pkts, time}_coal_set
...
New features:
- Make -a/--all-cpus be the default target in 'perf record' and 'perf stat',
just like it is with 'perf trace' (Jiri Olsa)
- Introduce -q/--quiet to the 'annotate', 'diff' and 'report', fix up
its behaviour in 'record'. This makes the output more compact by
elliminating headers, leaving just the histogram lines (Namhyung Kim)
Fixes:
- Handle offline/absent CPUs (Jan Stancek)
Infrastructure:
- Filter out -specs=/a/b/c from CC options when building the python
support, allowing that feature to be built with clang (Arnaldo Carvalho de Melo)
- Fix DEBUG=1 build with clang (Arnaldo Carvalho de Melo)
Trivial:
- Fix spelling of 'preempt' in a libtraceevent function name (Steven Rostedt)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-core-for-mingo-4.11-20170220' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent
Pull perf/core improvements and fixes from Arnaldo Carvalho de Melo:
New features:
- Make -a/--all-cpus be the default target in 'perf record' and 'perf stat',
just like it is with 'perf trace' (Jiri Olsa)
- Introduce -q/--quiet to the 'annotate', 'diff' and 'report', fix up
its behaviour in 'record'. This makes the output more compact by
elliminating headers, leaving just the histogram lines (Namhyung Kim)
Fixes:
- Handle offline/absent CPUs (Jan Stancek)
Infrastructure changes:
- Filter out -specs=/a/b/c from CC options when building the python
support, allowing that feature to be built with clang (Arnaldo Carvalho de Melo)
- Fix DEBUG=1 build with clang (Arnaldo Carvalho de Melo)
Trivial changes:
- Fix spelling of 'preempt' in a libtraceevent function name (Steven Rostedt)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull perf updates from Ingo Molnar:
"On the kernel side the main changes in this cycle were:
- Add Intel Kaby Lake CPU support (Srinivas Pandruvada)
- AMD uncore driver updates for fam17 (Janakarajan Natarajan)
- Intel/PT updates and core events optimizations and cleanups
(Alexander Shishkin)
- cgroups events fixes (David Carrillo-Cisneros)
- kprobes improvements (Masami Hiramatsu)
- ... plus misc fixes and updates.
On the tooling side the main changes were:
- Support clang build in tools/{perf,lib/{bpf,traceevent,api}} with
CC=clang, to, for instance, take advantage of better warnings
(Arnaldo Carvalho de Melo):
- Introduce the 'delta-abs' 'perf diff' compute method, that orders
the histogram entries by the absolute value of the percentage delta
for a function in two perf.data files, i.e. the functions that
changed the most (increase or decrease in samples) comes first
(Namhyung Kim)
- Add support for parsing Intel uncore vendor event files and add
uncore vendor events for the Intel server processors (Haswell,
Broadwell, IvyBridge), Xeon Phi (Knights Landing) and Broadwell DE
(Andi Kleen)
- Introduce 'perf ftrace' a perf front end to the kernel's ftrace
function and function_graph tracer, defaulting to the
"function_graph" tracer, more work will be done in reviving this
effort, forward porting it from its initial patch submission
(Namhyung Kim)
- Add 'e' and 'c' hotkeys to expand/collapse call chains for a single
hist entry in the 'perf report' and 'perf top' TUI (Jiri Olsa)
- Account thread wait time (off CPU time) separately: sleep, iowait
and preempt, based on the prev_state of the last event, show the
breakdown when using "perf sched timehist --state" (Namhyumg Kim)
- Add more triggers to switch the output file (perf.data.TIMESTAMP).
Now, in addition to switching to a different output file when
receiving a SIGUSR2, one can also specify file size and time based
triggers:
perf record -a --switch-output=signal
is equivalent to what we had before:
perf record -a --switch-output
While we can also ask for the file to be "sliced" by size, taking
into account that that will happen only when we get woken up by the
kernel, i.e. one has to take into account the --mmap-pages (the
size of the perf mmap ring buffer):
perf record -a --switch-output=2G
will break the perf.data output into multiple files limited to 2GB
of samples, right when generating the output.
For time based samples, alert() will be used, so to have 1 minute
limited perf.data output files:
perf record -a --switch-output=1m
(Jiri Olsa)
- Improve 'perf trace' (Arnaldo Carvalho de Melo)
- 'perf kallsyms' toy tool to look for extended symbol information on
the running kernel and demonstrate the machine/thread/symbol APIs
for use in other tools, such as 'perf probe' (Arnaldo Carvalho de
Melo)
- ... plus tons of other changes, see the shortlog and Git log for
details"
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (131 commits)
perf tools: Add missing parse_events_error() prototype
perf pmu: Fix check for unset alias->unit array
perf tools: Be consistent on the type of map->symbols[] interator
perf intel pt decoder: clang has no -Wno-override-init
perf evsel: Do not put a variable sized type not at the end of a struct
perf probe: Avoid accessing uninitialized 'map' variable
perf tools: Do not put a variable sized type not at the end of a struct
perf record: Do not put a variable sized type not at the end of a struct
perf tests: Synthesize struct instead of using field after variable sized type
perf bench numa: Make sure dprintf() is not defined
Revert "perf bench futex: Sanitize numeric parameters"
tools lib subcmd: Make it an error to pass a signed value to OPTION_UINTEGER
tools: Set the maximum optimization level according to the compiler being used
tools: Suppress request for warning options not existent in clang
samples/bpf: Reset global variables
samples/bpf: Ignore already processed ELF sections
samples/bpf: Add missing header
perf symbols: dso->name is an array, no need to check it against NULL
perf tests record: No need to test an array against NULL
perf symbols: No need to check if sym->name is NULL
...
Fix the typo of the function name pevent_data_prempt_count()
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Fixes: c52d9e4e67 ("tools lib traceevent: Add retrieval of preempt count and latency flags")
Link: http://lkml.kernel.org/r/20170216201352.469c99de@grimm.local.home
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Remove a useless ifdef __NR_bpf as requested by Wang Nan.
Inline one-line static functions as it was in the bpf_sys.h file.
Signed-off-by: Mickaël Salaün <mic@digikod.net>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David S. Miller <davem@davemloft.net>
Cc: Wang Nan <wangnan0@huawei.com>
Link: https://lkml.kernel.org/r/828ab1ff-4dcf-53ff-c97b-074adb895006@huawei.com
Acked-by: Wang Nan <wangnan0@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Options marked OPTION_UINTEGER or OPTION_U64 clearly indicates that an
unsigned value is expected, so just error out when a negative value is
passed, instead of returning something undesired to the tool.
E.g.:
# perf bench futex hash -t -4
# Running 'futex/hash' benchmark:
Error: switch `t' expects an unsigned numerical value
Usage: perf bench futex hash <options>
-t, --threads <n> Specify amount of threads
#
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-2mdn8s2raatyhz7tamrsz22r@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To avoid this when using clang:
warning: optimization level '-O6' is not supported; using '-O3' instead
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-kaghp8ddvzdsg03putemcq96@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Detected with clang:
CC /tmp/build/perf/plugin_function.o
plugin_function.c:145:6: warning: variable 'index' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized]
if (parent && ftrace_indent->set)
^~~~~~~~~~~~~~~~~~~~~~~~~~~~
plugin_function.c:148:29: note: uninitialized use occurs here
trace_seq_printf(s, "%*s", index*3, "");
^~~~~
plugin_function.c:145:2: note: remove the 'if' if its condition is always true
if (parent && ftrace_indent->set)
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
plugin_function.c:145:6: warning: variable 'index' is used uninitialized whenever '&&' condition is false [-Wsometimes-uninitialized]
if (parent && ftrace_indent->set)
^~~~~~
plugin_function.c:148:29: note: uninitialized use occurs here
trace_seq_printf(s, "%*s", index*3, "");
^~~~~
plugin_function.c:145:6: note: remove the '&&' if its condition is always true
if (parent && ftrace_indent->set)
^~~~~~~~~
plugin_function.c:133:11: note: initialize the variable 'index' to silence this warning
int index;
^
= 0
2 warnings generated.
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-b5wyjocel55gorl2jq2cbxrr@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
A undefined value was being used for the OLD_RING_BUFFER_TYPE_TIME_STAMP
case entry, as the 'length' variable was not being initialized, fix it.
Caught by the reporter when building tools/perf/ using clang, which emmitted
this warning:
kbuffer-parse.c:312:7: warning: variable 'length' is used uninitialized whenever switch case is taken [-Wsometimes-uninitialized]
case OLD_RINGBUF_TYPE_TIME_EXTEND:
^~~~~~~~~~~~~~~~~~~~~~~~~~~~
kbuffer-parse.c:339:29: note: uninitialized use occurs here
kbuf->next = kbuf->index + length;
^~~~~~
kbuffer-parse.c:297:21: note: initialize the variable 'length' to silence this warning
unsigned int length;
^
= 0
Reported-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20170213121418.47f279e8@gandalf.local.home
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
If BPF_F_ALLOW_OVERRIDE flag is used in BPF_PROG_ATTACH command
to the given cgroup the descendent cgroup will be able to override
effective bpf program that was inherited from this cgroup.
By default it's not passed, therefore override is disallowed.
Examples:
1.
prog X attached to /A with default
prog Y fails to attach to /A/B and /A/B/C
Everything under /A runs prog X
2.
prog X attached to /A with allow_override.
prog Y fails to attach to /A/B with default (non-override)
prog M attached to /A/B with allow_override.
Everything under /A/B runs prog M only.
3.
prog X attached to /A with allow_override.
prog Y fails to attach to /A with default.
The user has to detach first to switch the mode.
In the future this behavior may be extended with a chain of
non-overridable programs.
Also fix the bug where detach from cgroup where nothing is attached
was not throwing error. Return ENOENT in such case.
Add several testcases and adjust libbpf.
Fixes: 3007098494 ("cgroup: add support for eBPF programs")
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Daniel Mack <daniel@zonque.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Include stddef.h to define size_t.
Signed-off-by: Mickaël Salaün <mic@digikod.net>
Acked-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David S. Miller <davem@davemloft.net>
Cc: Joe Stringer <joe@ovn.org>
Link: http://lkml.kernel.org/r/20170207205609.8035-2-mic@digikod.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
The dynamic-list-file used to export dynamic symbols introduced in
commit e3d09ec812 ("tools lib traceevent: Export dynamic symbols
used by traceevent plugins")
is generated without any sort of error checking.
I experienced problems due to an old version of nm (v 0.158) that outputs
in a format distinct from the assumed by the script.
Robustify the built of dynamic symbol list by enforcing that the second
column of $(NM) -u <files> is either "U" (Undefined), "W" or "w" (undefined
weak), which are the possible outputs from non-ancient $(NM) versions.
Print an error if format is unexpected.
v2: Accept "W" and "w" symbol options.
Signed-off-by: David Carrillo-Cisneros <davidcc@google.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: He Kuang <hekuang@huawei.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Michal Marek <mmarek@suse.com>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/r/20170208052840.112182-1-davidcc@google.com
[ Use STRING1 = STRING1 instead of == to make this work on Ubuntu systems ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
All events from 'perf list', except SDT events, can be directly recorded
with 'perf record'. But, the flow is little different for SDT events.
Probe points for SDT event needs to be created using 'perf probe' before
recording it using 'perf record'.
Perf shows misleading hint when a user tries to record SDT event without
first creating a probe point. Show proper hint there.
Before patch:
$ perf record -a -e sdt_glib:idle__add
event syntax error: 'sdt_glib:idle__add'
\___ unknown tracepoint
Error: File /sys/kernel/debug/tracing/events/sdt_glib/idle__add not found.
Hint: Perhaps this kernel misses some CONFIG_ setting to enable this feature?.
...
After patch:
$ perf record -a -e sdt_glib:idle__add
event syntax error: 'sdt_glib:idle__add'
\___ unknown tracepoint
Error: File /sys/kernel/debug/tracing/events/sdt_glib/idle__add not found.
Hint: SDT event cannot be directly recorded on.
Please first use 'perf probe sdt_glib:idle__add' before recording it.
...
$ perf probe sdt_glib:idle__add
Added new event:
sdt_glib:idle__add (on %idle__add in /usr/lib64/libglib-2.0.so.0.5000.2)
You can now use it in all perf tools, such as:
perf record -e sdt_glib:idle__add -aR sleep 1
$ perf record -a -e sdt_glib:idle__add
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.175 MB perf.data ]
Suggested-and-Acked-by: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexis Berlemont <alexis.berlemont@gmail.com>
Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170203102642.17258-1-ravi.bangoria@linux.vnet.ibm.com
[ s/Please use/Please first use/ and break the Hint line in two ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Allow mounting of the BPF filesystem at /sys/fs/bpf.
Signed-off-by: Joe Stringer <joe@ovn.org>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: netdev@vger.kernel.org
Link: http://lkml.kernel.org/r/20170126212001.14103-6-joe@ovn.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add a new API to pin a BPF object to the filesystem. The user can
specify the path within a BPF filesystem to pin the object.
Programs will be pinned under a subdirectory named the same as the
program, with each instance appearing as a numbered file under that
directory, and maps will be pinned under the path using the name of
the map as the file basename.
For example, with the directory '/sys/fs/bpf/foo' and a BPF object which
contains two instances of a program named 'bar', and a map named 'baz':
/sys/fs/bpf/foo/bar/0
/sys/fs/bpf/foo/bar/1
/sys/fs/bpf/foo/baz
Signed-off-by: Joe Stringer <joe@ovn.org>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: netdev@vger.kernel.org
Link: http://lkml.kernel.org/r/20170126212001.14103-4-joe@ovn.org
[ Check snprintf >= for truncation, as snprintf(bf, size, ...) == size also means truncation ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add a new API to pin a BPF map to the filesystem. The user can specify
the path full path within a BPF filesystem to pin the map.
Signed-off-by: Joe Stringer <joe@ovn.org>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: netdev@vger.kernel.org
Link: http://lkml.kernel.org/r/20170126212001.14103-3-joe@ovn.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add new APIs to pin a BPF program (or specific instances) to the
filesystem. The user can specify the path full path within a BPF
filesystem to pin the program.
bpf_program__pin_instance(prog, path, n) will pin the nth instance of
'prog' to the specified path.
bpf_program__pin(prog, path) will create the directory 'path' (if it
does not exist) and pin each instance within that directory. For
instance, path/0, path/1, path/2.
Committer notes:
- Add missing headers for mkdir()
- Check strdup() for failure
- Check snprintf >= size, not >, as == also means truncated, see 'man
snprintf', return value.
- Conditionally define BPF_FS_MAGIC, as it isn't in magic.h in older
systems and we're not yet having a tools/include/uapi/linux/magic.h
copy.
- Do not include linux/magic.h, not present in older distros.
Signed-off-by: Joe Stringer <joe@ovn.org>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: netdev@vger.kernel.org
Link: http://lkml.kernel.org/r/20170126212001.14103-2-joe@ovn.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
This function will turn a libbpf pointer into a standard error code (or
0 if the pointer is valid).
This also allows removal of the dependency on linux/err.h in the public
header file, which causes problems in userspace programs built against
libbpf.
Signed-off-by: Joe Stringer <joe@ovn.org>
Acked-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: netdev@vger.kernel.org
Link: http://lkml.kernel.org/r/20170123011128.26534-5-joe@ovn.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
These bpf_prog_types were exposed in the uapi but there were no
corresponding functions to set these types for programs in libbpf.
Signed-off-by: Joe Stringer <joe@ovn.org>
Acked-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: netdev@vger.kernel.org
Link: http://lkml.kernel.org/r/20170123011128.26534-4-joe@ovn.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Turning this into a macro allows future prog types to be added with a
single line per type.
Signed-off-by: Joe Stringer <joe@ovn.org>
Acked-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: netdev@vger.kernel.org
Link: http://lkml.kernel.org/r/20170123011128.26534-3-joe@ovn.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Commit 4708bbda5c ("tools lib bpf: Fix maps resolution") attempted to
fix map resolution by identifying the number of symbols that point to
maps, and using this number to resolve each of the maps.
However, during relocation the original definition of the map size was
still in use. For up to two maps, the calculation was correct if there
was a small difference in size between the map definition in libbpf and
the one that the client library uses. However if the difference was
large, particularly if more than two maps were used in the BPF program,
the relocation would fail.
For example, when using a map definition with size 28, with three maps,
map relocation would count:
(sym_offset / sizeof(struct bpf_map_def) => map_idx)
(0 / 16 => 0), ie map_idx = 0
(28 / 16 => 1), ie map_idx = 1
(56 / 16 => 3), ie map_idx = 3
So, libbpf reports:
libbpf: bpf relocation: map_idx 3 large than 2
Fix map relocation by checking the exact offset of maps when doing
relocation.
Signed-off-by: Joe Stringer <joe@ovn.org>
[Allow different map size in an object]
Signed-off-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: netdev@vger.kernel.org
Fixes: 4708bbda5c ("tools lib bpf: Fix maps resolution")
Link: http://lkml.kernel.org/r/20170123011128.26534-2-joe@ovn.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Add support for the __print_hex_str() macro that was added for
tracing, so that user space tools such as perf can understand
it as well.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds missing member names to struct initializations.
Although in C99 for struct S {int x, int y} two init codes struct S s =
{.x = (a), (b)} and struct S s = {.x = (a), .y = (b)} are the same, it
is better to explicitly write .y (.argh in this patch) for readability
and robustness against language/compiler evolutions.
Signed-off-by: Soramichi Akiyama <akiyama@m.soramichi.jp>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20170113215623.32fb1ac2d862af0048c30fe6@m.soramichi.jp
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
As it was getting the BUILD_BUG_ON_ZERO() definition by luck.
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/n/tip-dh71o31ar72ajck8o2x4aoae@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Fixes:
- Fix prev/next_prio formatting for deadline tasks in libtraceevent (Daniel Bristot de Oliveira)
- Robustify reading of build-ids from /sys/kernel/note (Arnaldo Carvalho de Melo)
- Fix building some sample/bpf in Alpine Linux 3.4 (Arnaldo Carvalho de Melo)
- Fix 'make install-bin' to install libtraceevent plugins (Arnaldo Carvalho de Melo)
- Fix 'perf record --switch-output' documentation and comment (Jiri Olsa)
- 'perf probe' fixes for cross arch probing (Masami Hiramatsu)
Improvement:
- Show total scheduling time in 'perf sched timehist' (Namhyumg Kim)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
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Merge tag 'perf-urgent-for-mingo-4.10-20170104' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/urgent
Pull perf/urgent fixes and one improvement from Arnaldo Carvalho de Melo:
Fixes:
- Fix prev/next_prio formatting for deadline tasks in libtraceevent (Daniel Bristot de Oliveira)
- Robustify reading of build-ids from /sys/kernel/note (Arnaldo Carvalho de Melo)
- Fix building some sample/bpf in Alpine Linux 3.4 (Arnaldo Carvalho de Melo)
- Fix 'make install-bin' to install libtraceevent plugins (Arnaldo Carvalho de Melo)
- Fix 'perf record --switch-output' documentation and comment (Jiri Olsa)
- Fix 'perf probe' for cross arch probing (Masami Hiramatsu)
Improvement:
- Show total scheduling time in 'perf sched timehist' (Namhyumg Kim)
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Currently, the sched:sched_switch tracepoint reports deadline tasks with
priority -1. But when reading the trace via perf script I've got the
following output:
# ./d & # (d is a deadline task, see [1])
# perf record -e sched:sched_switch -a sleep 1
# perf script
...
swapper 0 [000] 2146.962441: sched:sched_switch: swapper/0:0 [120] R ==> d:2593 [4294967295]
d 2593 [000] 2146.972472: sched:sched_switch: d:2593 [4294967295] R ==> g:2590 [4294967295]
The task d reports the wrong priority [4294967295]. This happens because
the "int prio" is stored in an unsigned long long val. Although it is
set as a %lld, as int is shorter than unsigned long long,
trace_seq_printf prints it as a positive number.
The fix is just to cast the val as an int, and print it as a %d,
as in the sched:sched_switch tracepoint's "format".
The output with the fix is:
# ./d &
# perf record -e sched:sched_switch -a sleep 1
# perf script
...
swapper 0 [000] 4306.374037: sched:sched_switch: swapper/0:0 [120] R ==> d:10941 [-1]
d 10941 [000] 4306.383823: sched:sched_switch: d:10941 [-1] R ==> swapper/0:0 [120]
[1] d.c
---
#include <stdio.h>
#include <unistd.h>
#include <sys/syscall.h>
#include <linux/types.h>
#include <linux/sched.h>
struct sched_attr {
__u32 size, sched_policy;
__u64 sched_flags;
__s32 sched_nice;
__u32 sched_priority;
__u64 sched_runtime, sched_deadline, sched_period;
};
int sched_setattr(pid_t pid, const struct sched_attr *attr, unsigned int flags)
{
return syscall(__NR_sched_setattr, pid, attr, flags);
}
int main(void)
{
struct sched_attr attr = {
.size = sizeof(attr),
.sched_policy = SCHED_DEADLINE, /* This creates a 10ms/30ms reservation */
.sched_runtime = 10 * 1000 * 1000,
.sched_period = attr.sched_deadline = 30 * 1000 * 1000,
};
if (sched_setattr(0, &attr, 0) < 0) {
perror("sched_setattr");
return -1;
}
for(;;);
}
---
Committer notes:
Got the program from the provided URL, http://bristot.me/lkml/d.c,
trimmed it and included in the cset log above, so that we have
everything needed to test it in one place.
Signed-off-by: Daniel Bristot de Oliveira <bristot@redhat.com>
Acked-by: Steven Rostedt <rostedt@goodmis.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Daniel Bristot de Oliveira <bristot@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/866ef75bcebf670ae91c6a96daa63597ba981f0d.1483443552.git.bristot@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To allow string options with a default argument and variable set when
the option is used.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Tested-by: Wang Nan <wangnan0@huawei.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1483431600-19887-2-git-send-email-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull perf fixes from Ingo Molnar:
"On the kernel side there's two x86 PMU driver fixes and a uprobes fix,
plus on the tooling side there's a number of fixes and some late
updates"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits)
perf sched timehist: Fix invalid period calculation
perf sched timehist: Remove hardcoded 'comm_width' check at print_summary
perf sched timehist: Enlarge default 'comm_width'
perf sched timehist: Honour 'comm_width' when aligning the headers
perf/x86: Fix overlap counter scheduling bug
perf/x86/pebs: Fix handling of PEBS buffer overflows
samples/bpf: Move open_raw_sock to separate header
samples/bpf: Remove perf_event_open() declaration
samples/bpf: Be consistent with bpf_load_program bpf_insn parameter
tools lib bpf: Add bpf_prog_{attach,detach}
samples/bpf: Switch over to libbpf
perf diff: Do not overwrite valid build id
perf annotate: Don't throw error for zero length symbols
perf bench futex: Fix lock-pi help string
perf trace: Check if MAP_32BIT is defined (again)
samples/bpf: Make perf_event_read() static
uprobes: Fix uprobes on MIPS, allow for a cache flush after ixol breakpoint creation
samples/bpf: Make samples more libbpf-centric
tools lib bpf: Add flags to bpf_create_map()
tools lib bpf: use __u32 from linux/types.h
...
Commit d8c5b17f2b ("samples: bpf: add userspace example for attaching
eBPF programs to cgroups") added these functions to samples/libbpf, but
during this merge all of the samples libbpf functionality is shifting to
tools/lib/bpf. Shift these functions there.
Committer notes:
Use bzero + attr.FIELD = value instead of 'attr = { .FIELD = value, just
like the other wrapper calls to sys_bpf with bpf_attr to make this build
in older toolchais, such as the ones in CentOS 5 and 6.
Signed-off-by: Joe Stringer <joe@ovn.org>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-au2zvtsh55vqeo3v3uw7jr4c@git.kernel.org
Link: 353e6f298c.patch
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Pull kbuild updates from Michal Marek:
- prototypes for x86 asm-exported symbols (Adam Borowski) and a warning
about missing CRCs (Nick Piggin)
- asm-exports fix for LTO (Nicolas Pitre)
- thin archives improvements (Nick Piggin)
- linker script fix for CONFIG_LD_DEAD_CODE_DATA_ELIMINATION (Nick
Piggin)
- genksyms support for __builtin_va_list keyword
- misc minor fixes
* 'kbuild' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
x86/kbuild: enable modversions for symbols exported from asm
kbuild: fix scripts/adjust_autoksyms.sh* for the no modules case
scripts/kallsyms: remove last remnants of --page-offset option
make use of make variable CURDIR instead of calling pwd
kbuild: cmd_export_list: tighten the sed script
kbuild: minor improvement for thin archives build
kbuild: modpost warn if export version crc is missing
kbuild: keep data tables through dead code elimination
kbuild: improve linker compatibility with lib-ksyms.o build
genksyms: Regenerate parser
kbuild/genksyms: handle va_list type
kbuild: thin archives for multi-y targets
kbuild: kallsyms allow 3-pass generation if symbols size has changed
Commit 6c90598174 ("bpf: pre-allocate hash map elements") introduces
map_flags to bpf_attr for BPF_MAP_CREATE command. Expose this new
parameter in libbpf.
By exposing it, users can access flags such as whether or not to
preallocate the map.
Signed-off-by: Joe Stringer <joe@ovn.org>
Acked-by: Wang Nan <wangnan0@huawei.com>
Cc: Alexei Starovoitov <ast@fb.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Link: http://lkml.kernel.org/r/20161209024620.31660-4-joe@ovn.org
[ Added clarifying comment made by Wang Nan ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
