kernel/include/trace/events/xdp.h, branch linux-4.15.y

trace/xdp: fix compile warning: 'struct bpf_map' declared inside parameter list

2017-11-30T01:55:02Z

We meet this compile warning, which caused by missing bpf.h in xdp.h. In file included from ./include/trace/events/xdp.h:10:0, from ./include/linux/bpf_trace.h:6, from drivers/net/ethernet/intel/i40e/i40e_txrx.c:29: ./include/trace/events/xdp.h:93:17: warning: ‘struct bpf_map’ declared inside parameter list will not be visible outside of this definition or declaration const struct bpf_map *map, u32 map_index), ^ ./include/linux/tracepoint.h:187:34: note: in definition of macro ‘__DECLARE_TRACE’ static inline void trace_##name(proto) \ ^~~~~ ./include/linux/tracepoint.h:352:24: note: in expansion of macro ‘PARAMS’ __DECLARE_TRACE(name, PARAMS(proto), PARAMS(args), \ ^~~~~~ ./include/linux/tracepoint.h:477:2: note: in expansion of macro ‘DECLARE_TRACE’ DECLARE_TRACE(name, PARAMS(proto), PARAMS(args)) ^~~~~~~~~~~~~ ./include/linux/tracepoint.h:477:22: note: in expansion of macro ‘PARAMS’ DECLARE_TRACE(name, PARAMS(proto), PARAMS(args)) ^~~~~~ ./include/trace/events/xdp.h:89:1: note: in expansion of macro ‘DEFINE_EVENT’ DEFINE_EVENT(xdp_redirect_template, xdp_redirect, ^~~~~~~~~~~~ ./include/trace/events/xdp.h:90:2: note: in expansion of macro ‘TP_PROTO’ TP_PROTO(const struct net_device *dev, ^~~~~~~~ ./include/trace/events/xdp.h:93:17: warning: ‘struct bpf_map’ declared inside parameter list will not be visible outside of this definition or declaration const struct bpf_map *map, u32 map_index), ^ ./include/linux/tracepoint.h:203:38: note: in definition of macro ‘__DECLARE_TRACE’ register_trace_##name(void (*probe)(data_proto), void *data) \ ^~~~~~~~~~ ./include/linux/tracepoint.h:354:4: note: in expansion of macro ‘PARAMS’ PARAMS(void *__data, proto), \ ^~~~~~ Reported-by: Huang Daode Cc: Hanjun Guo Fixes: 8d3b778ff544 ("xdp: tracepoint xdp_redirect also need a map argument") Signed-off-by: Xie XiuQi Acked-by: Jesper Dangaard Brouer Acked-by: Steven Rostedt (VMware) Signed-off-by: Daniel Borkmann

Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

2017-11-04T00:26:51Z

Files removed in 'net-next' had their license header updated in 'net'. We take the remove from 'net-next'. Signed-off-by: David S. Miller

License cleanup: add SPDX GPL-2.0 license identifier to files with no license

2017-11-02T10:10:55Z

Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart Reviewed-by: Philippe Ombredanne Reviewed-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

bpf: cpumap add tracepoints

2017-10-18T11:12:18Z

This adds two tracepoint to the cpumap. One for the enqueue side trace_xdp_cpumap_enqueue() and one for the kthread dequeue side trace_xdp_cpumap_kthread(). To mitigate the tracepoint overhead, these are invoked during the enqueue/dequeue bulking phases, thus amortizing the cost. The obvious use-cases are for debugging and monitoring. The non-intuitive use-case is using these as a feedback loop to know the system load. One can imagine auto-scaling by reducing, adding or activating more worker CPUs on demand. V4: tracepoint remove time_limit info, instead add sched info V8: intro struct bpf_cpu_map_entry members cpu+map_id in this patch Signed-off-by: Jesper Dangaard Brouer Signed-off-by: David S. Miller

bpf: XDP_REDIRECT enable use of cpumap

2017-10-18T11:12:18Z

This patch connects cpumap to the xdp_do_redirect_map infrastructure. Still no SKB allocation are done yet. The XDP frames are transferred to the other CPU, but they are simply refcnt decremented on the remote CPU. This served as a good benchmark for measuring the overhead of remote refcnt decrement. If driver page recycle cache is not efficient then this, exposes a bottleneck in the page allocator. A shout-out to MST's ptr_ring, which is the secret behind is being so efficient to transfer memory pointers between CPUs, without constantly bouncing cache-lines between CPUs. V3: Handle !CONFIG_BPF_SYSCALL pointed out by kbuild test robot. V4: Make Generic-XDP aware of cpumap type, but don't allow redirect yet, as implementation require a separate upstream discussion. V5: - Fix a maybe-uninitialized pointed out by kbuild test robot. - Restrict bpf-prog side access to cpumap, open when use-cases appear - Implement cpu_map_enqueue() as a more simple void pointer enqueue V6: - Allow cpumap type for usage in helper bpf_redirect_map, general bpf-prog side restriction moved to earlier patch. Signed-off-by: Jesper Dangaard Brouer Signed-off-by: David S. Miller

xdp: implement xdp_redirect_map for generic XDP

2017-09-11T21:33:00Z

Using bpf_redirect_map is allowed for generic XDP programs, but the appropriate map lookup was never performed in xdp_do_generic_redirect(). Instead the map-index is directly used as the ifindex. For the xdp_redirect_map sample in SKB-mode '-S', this resulted in trying sending on ifindex 0 which isn't valid, resulting in getting SKB packets dropped. Thus, the reported performance numbers are wrong in commit 24251c264798 ("samples/bpf: add option for native and skb mode for redirect apps") for the 'xdp_redirect_map -S' case. Before commit 109980b894e9 ("bpf: don't select potentially stale ri->map from buggy xdp progs") it could crash the kernel. Like this commit also check that the map_owner owner is correct before dereferencing the map pointer. But make sure that this API misusage can be caught by a tracepoint. Thus, allowing userspace via tracepoints to detect misbehaving bpf_progs. Fixes: 6103aa96ec07 ("net: implement XDP_REDIRECT for xdp generic") Fixes: 24251c264798 ("samples/bpf: add option for native and skb mode for redirect apps") Signed-off-by: Jesper Dangaard Brouer Signed-off-by: David S. Miller

xdp: separate xdp_redirect tracepoint in map case

2017-08-29T17:51:29Z

Creating as specific xdp_redirect_map variant of the xdp tracepoints allow users to write simpler/faster BPF progs that get attached to these tracepoints. Goal is to still keep the tracepoints in xdp_redirect and xdp_redirect_map similar enough, that a tool can read the top part of the TP_STRUCT and produce similar monitor statistics. Signed-off-by: Jesper Dangaard Brouer Signed-off-by: David S. Miller

xdp: separate xdp_redirect tracepoint in error case

2017-08-29T17:51:29Z

There is a need to separate the xdp_redirect tracepoint into two tracepoints, for separating the error case from the normal forward case. Due to the extreme speeds XDP is operating at, loading a tracepoint have a measurable impact. Single core XDP REDIRECT (ethtool tuned rx-usecs 25) can do 13.7 Mpps forwarding, but loading a simple bpf_prog at the tracepoint (with a return 0) reduce perf to 10.2 Mpps (CPU E5-1650 v4 @ 3.60GHz, driver: ixgbe) The overhead of loading a bpf-based tracepoint can be calculated to cost 25 nanosec ((1/13782002-1/10267937)*10^9 = -24.83 ns). Using perf record on the tracepoint event, with a non-matching --filter expression, the overhead is much larger. Performance drops to 8.3 Mpps, cost 48 nanosec ((1/13782002-1/8312497)*10^9 = -47.74)) Having a separate tracepoint for err cases, which should be less frequent, allow running a continuous monitor for errors while not affecting the redirect forward performance (this have also been verified by measurements). Signed-off-by: Jesper Dangaard Brouer Acked-by: Alexei Starovoitov Signed-off-by: David S. Miller

xdp: make xdp tracepoints report bpf prog id instead of prog_tag

2017-08-29T17:51:29Z

Given previous patch expose the map_id, it seems natural to also report the bpf prog id. Signed-off-by: Jesper Dangaard Brouer Signed-off-by: David S. Miller

xdp: tracepoint xdp_redirect also need a map argument

2017-08-29T17:51:28Z

To make sense of the map index, the tracepoint user also need to know that map we are talking about. Supply the map pointer but only expose the map->id. The 'to_index' is renamed 'to_ifindex'. In the xdp_redirect_map case, this is the result of the devmap lookup. The map lookup key is exposed as map_index, which is needed to troubleshoot in case the lookup failed. The 'to_ifindex' is placed after 'err' to keep TP_STRUCT as common as possible. This also keeps the TP_STRUCT similar enough, that userspace can write a monitor program, that doesn't need to care about whether bpf_redirect or bpf_redirect_map were used. Signed-off-by: Jesper Dangaard Brouer Signed-off-by: David S. Miller