summaryrefslogtreecommitdiff
AgeCommit message (Collapse)AuthorFilesLines
2019-12-21xsk: Eliminate the RX batch sizeMagnus Karlsson1-4/+2
In the xsk consumer ring code there is a variable called RX_BATCH_SIZE that dictates the minimum number of entries that we try to grab from the fill and Tx rings. In fact, the code always try to grab the maximum amount of entries from these rings. The only thing this variable does is to throw an error if there is less than 16 (as it is defined) entries on the ring. There is no reason to do this and it will just lead to weird behavior from user space's point of view. So eliminate this variable. With this change, we will be able to simplify the xskq_nb_free and xskq_nb_avail code in the next commit. Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/1576759171-28550-6-git-send-email-magnus.karlsson@intel.com
2019-12-21xsk: Standardize naming of producer ring access functionsMagnus Karlsson2-41/+37
Adopt the naming of the producer ring access functions to have a similar naming convention as the functions in libbpf, but adapted to the kernel. You first reserve a number of entries that you later submit to the global state of the ring. This is much clearer, IMO, than the one that was in the kernel part. Once renamed, we also discover that two functions are actually the same, so remove one of them. Some of the primitive ring submission operations are also the same so break these out into __xskq_prod_submit that the upper level ring access functions can use. Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/1576759171-28550-5-git-send-email-magnus.karlsson@intel.com
2019-12-21xsk: Consolidate to one single cached producer pointerMagnus Karlsson1-26/+21
Currently, the xsk ring code has two cached producer pointers: prod_head and prod_tail. This patch consolidates these two into a single one called cached_prod to make the code simpler and easier to maintain. This will be in line with the user space part of the the code found in libbpf, that only uses a single cached pointer. The Rx path only uses the two top level functions xskq_produce_batch_desc and xskq_produce_flush_desc and they both use prod_head and never prod_tail. So just move them over to cached_prod. The Tx XDP_DRV path uses xskq_produce_addr_lazy and xskq_produce_flush_addr_n and unnecessarily operates on both prod_tail and prod_head, so move them over to just use cached_prod by skipping the intermediate step of updating prod_tail. The Tx path in XDP_SKB mode uses xskq_reserve_addr and xskq_produce_addr. They currently use both cached pointers, but we can operate on the global producer pointer in xskq_produce_addr since it has to be updated anyway, thus eliminating the use of both cached pointers. We can also remove the xskq_nb_free in xskq_produce_addr since it is already called in xskq_reserve_addr. No need to do it twice. When there is only one cached producer pointer, we can also simplify xskq_nb_free by removing one argument. Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/1576759171-28550-4-git-send-email-magnus.karlsson@intel.com
2019-12-21xsk: Simplify detection of empty and full ringsMagnus Karlsson1-2/+5
In order to set the correct return flags for poll, the xsk code has to check if the Rx queue is empty and if the Tx queue is full. This code was unnecessarily large and complex as it used the functions that are used to update the local state from the global state (xskq_nb_free and xskq_nb_avail). Since we are not doing this nor updating any data dependent on this state, we can simplify the functions. Another benefit from this is that we can also simplify the xskq_nb_free and xskq_nb_avail functions in a later commit. Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/1576759171-28550-3-git-send-email-magnus.karlsson@intel.com
2019-12-21xsk: Eliminate the lazy update thresholdMagnus Karlsson1-2/+1
The lazy update threshold was introduced to keep the producer and consumer some distance apart in the completion ring. This was important in the beginning of the development of AF_XDP as the ring format as that point in time was very sensitive to the producer and consumer being on the same cache line. This is not the case anymore as the current ring format does not degrade in any noticeable way when this happens. Moreover, this threshold makes it impossible to run the system with rings that have less than 128 entries. So let us remove this threshold and just get one entry from the ring as in all other functions. This will enable us to remove this function in a later commit. Note that xskq_produce_addr_lazy followed by xskq_produce_flush_addr_n are still not the same function as xskq_produce_addr() as it operates on another cached pointer. Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/1576759171-28550-2-git-send-email-magnus.karlsson@intel.com
2019-12-20Merge branch 'replace-cg_bpf-prog'Alexei Starovoitov15-626/+652
Andrey Ignatov says: ==================== v3->v4: - use OPTS_VALID and OPTS_GET to handle bpf_prog_attach_opts. v2->v3: - rely on DECLARE_LIBBPF_OPTS from libbpf_common.h; - separate "required" and "optional" arguments in bpf_prog_attach_xattr; - convert test_cgroup_attach to prog_tests; - move the new selftest to prog_tests/cgroup_attach_multi. v1->v2: - move DECLARE_LIBBPF_OPTS from libbpf.h to bpf.h (patch 4); - switch new libbpf API to OPTS framework; - switch selftest to libbpf OPTS framework. This patch set adds support for replacing cgroup-bpf programs attached with BPF_F_ALLOW_MULTI flag so that any program in a list can be updated to a new version without service interruption and order of programs can be preserved. Please see patch 3 for details on the use-case and API changes. Other patches: Patch 1 is preliminary refactoring of __cgroup_bpf_attach to simplify it. Patch 2 is minor cleanup of hierarchy_allows_attach. Patch 4 extends libbpf API to support new set of attach attributes. Patch 5 converts test_cgroup_attach to prog_tests. Patch 6 adds selftest coverage for the new API. ==================== Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-12-20selftests/bpf: Test BPF_F_REPLACE in cgroup_attach_multiAndrey Ignatov1-3/+50
Test replacing a cgroup-bpf program attached with BPF_F_ALLOW_MULTI and possible failure modes: invalid combination of flags, invalid replace_bpf_fd, replacing a non-attachd to specified cgroup program. Example of program replacing: # gdb -q --args ./test_progs --name=cgroup_attach_multi ... Breakpoint 1, test_cgroup_attach_multi () at cgroup_attach_multi.c:227 (gdb) [1]+ Stopped gdb -q --args ./test_progs --name=cgroup_attach_multi # bpftool c s /mnt/cgroup2/cgroup-test-work-dir/cg1 ID AttachType AttachFlags Name 2133 egress multi 2134 egress multi # fg gdb -q --args ./test_progs --name=cgroup_attach_multi (gdb) c Continuing. Breakpoint 2, test_cgroup_attach_multi () at cgroup_attach_multi.c:233 (gdb) [1]+ Stopped gdb -q --args ./test_progs --name=cgroup_attach_multi # bpftool c s /mnt/cgroup2/cgroup-test-work-dir/cg1 ID AttachType AttachFlags Name 2139 egress multi 2134 egress multi Signed-off-by: Andrey Ignatov <rdna@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/7b9b83e8d5fb82e15b034341bd40b6fb2431eeba.1576741281.git.rdna@fb.com
2019-12-20selftests/bpf: Convert test_cgroup_attach to prog_testsAndrey Ignatov6-574/+498
Convert test_cgroup_attach to prog_tests. This change does a lot of things but in many cases it's pretty expensive to separate them, so they go in one commit. Nevertheless the logic is ketp as is and changes made are just moving things around, simplifying them (w/o changing the meaning of the tests) and making prog_tests compatible: * split the 3 tests in the file into 3 separate files in prog_tests/; * rename the test functions to test_<file_base_name>; * remove unused includes, constants, variables and functions from every test; * replace `if`-s with or `if (CHECK())` where additional context should be logged and with `if (CHECK_FAIL())` where line number is enough; * switch from `log_err()` to logging via `CHECK()`; * replace `assert`-s with `CHECK_FAIL()` to avoid crashing the whole test_progs if one assertion fails; * replace cgroup_helpers with test__join_cgroup() in cgroup_attach_override only, other tests need more fine-grained control for cgroup creation/deletion so cgroup_helpers are still used there; * simplify cgroup_attach_autodetach by switching to easiest possible program since this test doesn't really need such a complicated program as cgroup_attach_multi does; * remove test_cgroup_attach.c itself. Signed-off-by: Andrey Ignatov <rdna@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/0ff19cc64d2dc5cf404349f07131119480e10e32.1576741281.git.rdna@fb.com
2019-12-20libbpf: Introduce bpf_prog_attach_xattrAndrey Ignatov3-1/+28
Introduce a new bpf_prog_attach_xattr function that, in addition to program fd, target fd and attach type, accepts an extendable struct bpf_prog_attach_opts. bpf_prog_attach_opts relies on DECLARE_LIBBPF_OPTS macro to maintain backward and forward compatibility and has the following "optional" attach attributes: * existing attach_flags, since it's not required when attaching in NONE mode. Even though it's quite often used in MULTI and OVERRIDE mode it seems to be a good idea to reduce number of arguments to bpf_prog_attach_xattr; * newly introduced attribute of BPF_PROG_ATTACH command: replace_prog_fd that is fd of previously attached cgroup-bpf program to replace if BPF_F_REPLACE flag is used. The new function is named to be consistent with other xattr-functions (bpf_prog_test_run_xattr, bpf_create_map_xattr, bpf_load_program_xattr). The struct bpf_prog_attach_opts is supposed to be used with DECLARE_LIBBPF_OPTS macro. Signed-off-by: Andrey Ignatov <rdna@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/bd6e0732303eb14e4b79cb128268d9e9ad6db208.1576741281.git.rdna@fb.com
2019-12-20bpf: Support replacing cgroup-bpf program in MULTI modeAndrey Ignatov6-9/+54
The common use-case in production is to have multiple cgroup-bpf programs per attach type that cover multiple use-cases. Such programs are attached with BPF_F_ALLOW_MULTI and can be maintained by different people. Order of programs usually matters, for example imagine two egress programs: the first one drops packets and the second one counts packets. If they're swapped the result of counting program will be different. It brings operational challenges with updating cgroup-bpf program(s) attached with BPF_F_ALLOW_MULTI since there is no way to replace a program: * One way to update is to detach all programs first and then attach the new version(s) again in the right order. This introduces an interruption in the work a program is doing and may not be acceptable (e.g. if it's egress firewall); * Another way is attach the new version of a program first and only then detach the old version. This introduces the time interval when two versions of same program are working, what may not be acceptable if a program is not idempotent. It also imposes additional burden on program developers to make sure that two versions of their program can co-exist. Solve the problem by introducing a "replace" mode in BPF_PROG_ATTACH command for cgroup-bpf programs being attached with BPF_F_ALLOW_MULTI flag. This mode is enabled by newly introduced BPF_F_REPLACE attach flag and bpf_attr.replace_bpf_fd attribute to pass fd of the old program to replace That way user can replace any program among those attached with BPF_F_ALLOW_MULTI flag without the problems described above. Details of the new API: * If BPF_F_REPLACE is set but replace_bpf_fd doesn't have valid descriptor of BPF program, BPF_PROG_ATTACH will return corresponding error (EINVAL or EBADF). * If replace_bpf_fd has valid descriptor of BPF program but such a program is not attached to specified cgroup, BPF_PROG_ATTACH will return ENOENT. BPF_F_REPLACE is introduced to make the user intent clear, since replace_bpf_fd alone can't be used for this (its default value, 0, is a valid fd). BPF_F_REPLACE also makes it possible to extend the API in the future (e.g. add BPF_F_BEFORE and BPF_F_AFTER if needed). Signed-off-by: Andrey Ignatov <rdna@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Martin KaFai Lau <kafai@fb.com> Acked-by: Andrii Narkyiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/30cd850044a0057bdfcaaf154b7d2f39850ba813.1576741281.git.rdna@fb.com
2019-12-20bpf: Remove unused new_flags in hierarchy_allows_attach()Andrey Ignatov1-3/+2
new_flags is unused, remove it. Signed-off-by: Andrey Ignatov <rdna@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/bpf/2c49b30ab750f93cfef04a1e40b097d70c3a39a1.1576741281.git.rdna@fb.com
2019-12-20bpf: Simplify __cgroup_bpf_attachAndrey Ignatov1-39/+23
__cgroup_bpf_attach has a lot of identical code to handle two scenarios: BPF_F_ALLOW_MULTI is set and unset. Simplify it by splitting the two main steps: * First, the decision is made whether a new bpf_prog_list entry should be allocated or existing entry should be reused for the new program. This decision is saved in replace_pl pointer; * Next, replace_pl pointer is used to handle both possible states of BPF_F_ALLOW_MULTI flag (set / unset) instead of doing similar work for them separately. This splitting, in turn, allows to make further simplifications: * The check for attaching same program twice in BPF_F_ALLOW_MULTI mode can be done before allocating cgroup storage, so that if user tries to attach same program twice no alloc/free happens as it was before; * pl_was_allocated becomes redundant so it's removed. Signed-off-by: Andrey Ignatov <rdna@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Martin KaFai Lau <kafai@fb.com> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/c6193db6fe630797110b0d3ff06c125d093b834c.1576741281.git.rdna@fb.com
2019-12-20Merge branch 'simplify-do_redirect'Alexei Starovoitov8-197/+75
Björn Töpel says: ==================== This series aims to simplify the XDP maps and xdp_do_redirect_map()/xdp_do_flush_map(), and to crank out some more performance from XDP_REDIRECT scenarios. The first part of the series simplifies all XDP_REDIRECT capable maps, so that __XXX_flush_map() does not require the map parameter, by moving the flush list from the map to global scope. This results in that the map_to_flush member can be removed from struct bpf_redirect_info, and its corresponding logic. Simpler code, and more performance due to that checks/code per-packet is moved to flush. Pre-series performance: $ sudo taskset -c 22 ./xdpsock -i enp134s0f0 -q 20 -n 1 -r -z sock0@enp134s0f0:20 rxdrop xdp-drv pps pkts 1.00 rx 20,797,350 230,942,399 tx 0 0 $ sudo ./xdp_redirect_cpu --dev enp134s0f0 --cpu 22 xdp_cpu_map0 Running XDP/eBPF prog_name:xdp_cpu_map5_lb_hash_ip_pairs XDP-cpumap CPU:to pps drop-pps extra-info XDP-RX 20 7723038 0 0 XDP-RX total 7723038 0 cpumap_kthread total 0 0 0 redirect_err total 0 0 xdp_exception total 0 0 Post-series performance: $ sudo taskset -c 22 ./xdpsock -i enp134s0f0 -q 20 -n 1 -r -z sock0@enp134s0f0:20 rxdrop xdp-drv pps pkts 1.00 rx 21,524,979 86,835,327 tx 0 0 $ sudo ./xdp_redirect_cpu --dev enp134s0f0 --cpu 22 xdp_cpu_map0 Running XDP/eBPF prog_name:xdp_cpu_map5_lb_hash_ip_pairs XDP-cpumap CPU:to pps drop-pps extra-info XDP-RX 20 7840124 0 0 XDP-RX total 7840124 0 cpumap_kthread total 0 0 0 redirect_err total 0 0 xdp_exception total 0 0 Results: +3.5% and +1.5% for the ubenchmarks. v1->v2 [1]: * Removed 'unused-variable' compiler warning (Jakub) [1] https://lore.kernel.org/bpf/20191218105400.2895-1-bjorn.topel@gmail.com/ ==================== Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-12-20xdp: Simplify __bpf_tx_xdp_map()Björn Töpel1-26/+7
The explicit error checking is not needed. Simply return the error instead. Signed-off-by: Björn Töpel <bjorn.topel@intel.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://lore.kernel.org/bpf/20191219061006.21980-9-bjorn.topel@gmail.com
2019-12-20xdp: Remove map_to_flush and map swap detectionBjörn Töpel2-25/+3
Now that all XDP maps that can be used with bpf_redirect_map() tracks entries to be flushed in a global fashion, there is not need to track that the map has changed and flush from xdp_do_generic_map() anymore. All entries will be flushed in xdp_do_flush_map(). This means that the map_to_flush can be removed, and the corresponding checks. Moving the flush logic to one place, xdp_do_flush_map(), give a bulking behavior and performance boost. Signed-off-by: Björn Töpel <bjorn.topel@intel.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://lore.kernel.org/bpf/20191219061006.21980-8-bjorn.topel@gmail.com
2019-12-20xdp: Make cpumap flush_list common for all map instancesBjörn Töpel3-21/+21
The cpumap flush list is used to track entries that need to flushed from via the xdp_do_flush_map() function. This list used to be per-map, but there is really no reason for that. Instead make the flush list global for all devmaps, which simplifies __cpu_map_flush() and cpu_map_alloc(). Signed-off-by: Björn Töpel <bjorn.topel@intel.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://lore.kernel.org/bpf/20191219061006.21980-7-bjorn.topel@gmail.com
2019-12-20xdp: Make devmap flush_list common for all map instancesBjörn Töpel3-25/+16
The devmap flush list is used to track entries that need to flushed from via the xdp_do_flush_map() function. This list used to be per-map, but there is really no reason for that. Instead make the flush list global for all devmaps, which simplifies __dev_map_flush() and dev_map_init_map(). Signed-off-by: Björn Töpel <bjorn.topel@intel.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://lore.kernel.org/bpf/20191219061006.21980-6-bjorn.topel@gmail.com
2019-12-20xsk: Make xskmap flush_list common for all map instancesBjörn Töpel4-35/+20
The xskmap flush list is used to track entries that need to flushed from via the xdp_do_flush_map() function. This list used to be per-map, but there is really no reason for that. Instead make the flush list global for all xskmaps, which simplifies __xsk_map_flush() and xsk_map_alloc(). Signed-off-by: Björn Töpel <bjorn.topel@intel.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://lore.kernel.org/bpf/20191219061006.21980-5-bjorn.topel@gmail.com
2019-12-20xdp: Fix graze->grace type-o in cpumap commentsBjörn Töpel1-3/+3
Simple spelling fix. Signed-off-by: Björn Töpel <bjorn.topel@intel.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://lore.kernel.org/bpf/20191219061006.21980-4-bjorn.topel@gmail.com
2019-12-20xdp: Simplify cpumap cleanupBjörn Töpel1-29/+5
After the RCU flavor consolidation [1], call_rcu() and synchronize_rcu() waits for preempt-disable regions (NAPI) in addition to the read-side critical sections. As a result of this, the cleanup code in cpumap can be simplified * There is no longer a need to flush in __cpu_map_entry_free, since we know that this has been done when the call_rcu() callback is triggered. * When freeing the map, there is no need to explicitly wait for a flush. It's guaranteed to be done after the synchronize_rcu() call in cpu_map_free(). [1] https://lwn.net/Articles/777036/ Signed-off-by: Björn Töpel <bjorn.topel@intel.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://lore.kernel.org/bpf/20191219061006.21980-3-bjorn.topel@gmail.com
2019-12-20xdp: Simplify devmap cleanupBjörn Töpel1-38/+5
After the RCU flavor consolidation [1], call_rcu() and synchronize_rcu() waits for preempt-disable regions (NAPI) in addition to the read-side critical sections. As a result of this, the cleanup code in devmap can be simplified * There is no longer a need to flush in __dev_map_entry_free, since we know that this has been done when the call_rcu() callback is triggered. * When freeing the map, there is no need to explicitly wait for a flush. It's guaranteed to be done after the synchronize_rcu() call in dev_map_free(). The rcu_barrier() is still needed, so that the map is not freed prior the elements. [1] https://lwn.net/Articles/777036/ Signed-off-by: Björn Töpel <bjorn.topel@intel.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Toke Høiland-Jørgensen <toke@redhat.com> Link: https://lore.kernel.org/bpf/20191219061006.21980-2-bjorn.topel@gmail.com
2019-12-20bpf: Remove unnecessary assertion on fp_oldAditya Pakki1-2/+0
The two callers of bpf_prog_realloc - bpf_patch_insn_single and bpf_migrate_filter dereference the struct fp_old, before passing it to the function. Thus assertion to check fp_old is unnecessary and can be removed. Signed-off-by: Aditya Pakki <pakki001@umn.edu> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20191219175735.19231-1-pakki001@umn.edu
2019-12-19libbpf: Fix another __u64 printf warningAndrii Nakryiko1-2/+2
Fix yet another printf warning for %llu specifier on ppc64le. This time size_t casting won't work, so cast to verbose `unsigned long long`. Fixes: 166750bc1dd2 ("libbpf: Support libbpf-provided extern variables") Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20191219052103.3515-1-andriin@fb.com
2019-12-19libbpf: Fix printing of ulimit valueToke Høiland-Jørgensen1-1/+1
Naresh pointed out that libbpf builds fail on 32-bit architectures because rlimit.rlim_cur is defined as 'unsigned long long' on those architectures. Fix this by using %zu in printf and casting to size_t. Fixes: dc3a2d254782 ("libbpf: Print hint about ulimit when getting permission denied error") Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org> Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20191219090236.905059-1-toke@redhat.com
2019-12-19selftests/bpf: Fix test_attach_probeAlexei Starovoitov1-3/+4
Fix two issues in test_attach_probe: 1. it was not able to parse /proc/self/maps beyond the first line, since %s means parse string until white space. 2. offset has to be accounted for otherwise uprobed address is incorrect. Fixes: 1e8611bbdfc9 ("selftests/bpf: add kprobe/uprobe selftests") Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Yonghong Song <yhs@fb.com> Acked-by: Andrii Nakryiko <andriin@fb.com> Link: https://lore.kernel.org/bpf/20191219020442.1922617-1-ast@kernel.org
2019-12-19libbpf: Add missing newline in opts validation macroToke Høiland-Jørgensen1-1/+1
The error log output in the opts validation macro was missing a newline. Fixes: 2ce8450ef5a3 ("libbpf: add bpf_object__open_{file, mem} w/ extensible opts") Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20191219120714.928380-1-toke@redhat.com
2019-12-19Merge branch 'bpf-riscv-jit-improvements'Daniel Borkmann5-238/+312
Björn Töpel says: ==================== This series contain one non-critical fix, support for far jumps, and some optimizations for the BPF JIT. Previously, the JIT only supported 12b branch targets for conditional branches, and 21b for unconditional branches. Starting with this series, 32b branching is supported. As part of supporting far jumps, branch relaxation was introduced. The idea is to start with a pessimistic jump (e.g. auipc/jalr) and for each pass the JIT will have an opportunity to pick a better instruction (e.g. jal) and shrink the image. Instead of two passes, the JIT requires more passes. It typically converges after 3 passes. The optimizations mentioned in the subject are for calls and tail calls. In the tail call generation we can save one instruction by using the offset in jalr. Calls are optimized by doing (auipc)/jal(r) relative jumps instead of loading the entire absolute address and doing jalr. This required that the JIT image allocator was made RISC-V specific, so we can ensure that the JIT image and the kernel text are in range (32b). The last two patches of the series is not critical to the series, but are two UAPI build issues for BPF events. A closer look from the RV-folks would be much appreciated. The test_bpf.ko module, selftests/bpf/test_verifier and selftests/seccomp/seccomp_bpf pass all tests. RISC-V is still missing proper kprobe and tracepoint support, so a lot of BPF selftests cannot be run. v1->v2: [1] * Removed unused function parameter from emit_branch() * Added patch to support far branch in tail call emit [1] https://lore.kernel.org/bpf/20191209173136.29615-1-bjorn.topel@gmail.com/ ==================== Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
2019-12-19riscv, perf: Add arch specific perf_arch_bpf_user_pt_regsBjörn Töpel1-0/+4
RISC-V was missing a proper perf_arch_bpf_user_pt_regs macro for CONFIG_PERF_EVENT builds. Signed-off-by: Björn Töpel <bjorn.topel@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20191216091343.23260-10-bjorn.topel@gmail.com
2019-12-19riscv, bpf: Add missing uapi header for BPF_PROG_TYPE_PERF_EVENT programsBjörn Töpel2-0/+11
Add missing uapi header the BPF_PROG_TYPE_PERF_EVENT programs by exporting struct user_regs_struct instead of struct pt_regs which is in-kernel only. Signed-off-by: Björn Töpel <bjorn.topel@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20191216091343.23260-9-bjorn.topel@gmail.com
2019-12-19riscv, bpf: Optimize callsBjörn Töpel1-37/+64
Instead of using emit_imm() and emit_jalr() which can expand to six instructions, start using jal or auipc+jalr. Signed-off-by: Björn Töpel <bjorn.topel@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20191216091343.23260-8-bjorn.topel@gmail.com
2019-12-19riscv, bpf: Provide RISC-V specific JIT image alloc/freeBjörn Töpel2-0/+17
This commit makes sure that the JIT images is kept close to the kernel text, so BPF calls can use relative calling with auipc/jalr or jal instead of loading the full 64-bit address and jalr. The BPF JIT image region is 128 MB before the kernel text. Signed-off-by: Björn Töpel <bjorn.topel@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20191216091343.23260-7-bjorn.topel@gmail.com
2019-12-19riscv, bpf: Optimize BPF tail callsBjörn Töpel1-6/+7
Remove one addi, and instead use the offset part of jalr. Signed-off-by: Björn Töpel <bjorn.topel@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20191216091343.23260-6-bjorn.topel@gmail.com
2019-12-19riscv, bpf: Add support for far jumps and exitsBjörn Töpel1-20/+17
This commit add support for far (offset > 21b) jumps and exits. Signed-off-by: Björn Töpel <bjorn.topel@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Luke Nelson <lukenels@cs.washington.edu> Link: https://lore.kernel.org/bpf/20191216091343.23260-5-bjorn.topel@gmail.com
2019-12-19riscv, bpf: Add support for far branching when emitting tail callBjörn Töpel1-19/+3
Start use the emit_branch() function in the tail call emitter in order to support far branching. Signed-off-by: Björn Töpel <bjorn.topel@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20191216091343.23260-4-bjorn.topel@gmail.com
2019-12-19riscv, bpf: Add support for far branchingBjörn Töpel1-164/+188
This commit adds branch relaxation to the BPF JIT, and with that support for far (offset greater than 12b) branching. The branch relaxation requires more than two passes to converge. For most programs it is three passes, but for larger programs it can be more. Signed-off-by: Björn Töpel <bjorn.topel@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Reviewed-by: Luke Nelson <lukenels@cs.washington.edu> Link: https://lore.kernel.org/bpf/20191216091343.23260-3-bjorn.topel@gmail.com
2019-12-19riscv, bpf: Fix broken BPF tail callsBjörn Töpel1-2/+11
The BPF JIT incorrectly clobbered the a0 register, and did not flag usage of s5 register when BPF stack was being used. Fixes: 2353ecc6f91f ("bpf, riscv: add BPF JIT for RV64G") Signed-off-by: Björn Töpel <bjorn.topel@gmail.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Link: https://lore.kernel.org/bpf/20191216091343.23260-2-bjorn.topel@gmail.com
2019-12-19Merge branch 'libbpf-extern-followups'Alexei Starovoitov8-161/+194
Andrii Nakryiko says: ==================== Based on latest feedback and discussions, this patch set implements the following changes: - Kconfig-provided externs have to be in .kconfig section, for which bpf_helpers.h provides convenient __kconfig macro (Daniel); - instead of allowing to override Kconfig file path, switch this to ability to extend and override system Kconfig with user-provided custom values (Alexei); - BTF is required when externs are used. ==================== Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-12-19libbpf: BTF is required when externs are presentAndrii Nakryiko1-1/+2
BTF is required to get type information about extern variables. Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20191219002837.3074619-4-andriin@fb.com
2019-12-19libbpf: Allow to augment system Kconfig through extra optional configAndrii Nakryiko3-112/+132
Instead of all or nothing approach of overriding Kconfig file location, allow to extend it with extra values and override chosen subset of values though optional user-provided extra config, passed as a string through open options' .kconfig option. If same config key is present in both user-supplied config and Kconfig, user-supplied one wins. This allows applications to more easily test various conditions despite host kernel's real configuration. If all of BPF object's __kconfig externs are satisfied from user-supplied config, system Kconfig won't be read at all. Simplify selftests by not needing to create temporary Kconfig files. Suggested-by: Alexei Starovoitov <ast@fb.com> Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20191219002837.3074619-3-andriin@fb.com
2019-12-19libbpf: Put Kconfig externs into .kconfig sectionAndrii Nakryiko6-48/+60
Move Kconfig-provided externs into custom .kconfig section. Add __kconfig into bpf_helpers.h for user convenience. Update selftests accordingly. Suggested-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20191219002837.3074619-2-andriin@fb.com
2019-12-19libbpf: Add bpf_link__disconnect() API to preserve underlying BPF resourceAndrii Nakryiko3-10/+32
There are cases in which BPF resource (program, map, etc) has to outlive userspace program that "installed" it in the system in the first place. When BPF program is attached, libbpf returns bpf_link object, which is supposed to be destroyed after no longer necessary through bpf_link__destroy() API. Currently, bpf_link destruction causes both automatic detachment and frees up any resources allocated to for bpf_link in-memory representation. This is inconvenient for the case described above because of coupling of detachment and resource freeing. This patch introduces bpf_link__disconnect() API call, which marks bpf_link as disconnected from its underlying BPF resouces. This means that when bpf_link is destroyed later, all its memory resources will be freed, but BPF resource itself won't be detached. This design allows to follow strict and resource-leak-free design by default, while giving easy and straightforward way for user code to opt for keeping BPF resource attached beyond lifetime of a bpf_link. For some BPF programs (i.e., FS-based tracepoints, kprobes, raw tracepoint, etc), user has to make sure to pin BPF program to prevent kernel to automatically detach it on process exit. This should typically be achived by pinning BPF program (or map in some cases) in BPF FS. Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Martin KaFai Lau <kafai@fb.com> Link: https://lore.kernel.org/bpf/20191218225039.2668205-1-andriin@fb.com
2019-12-19bpf: Allow to change skb mark in test_runNikita V. Shirokov3-1/+15
allow to pass skb's mark field into bpf_prog_test_run ctx for BPF_PROG_TYPE_SCHED_CLS prog type. that would allow to test bpf programs which are doing decision based on this field Signed-off-by: Nikita V. Shirokov <tehnerd@tehnerd.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-12-19bpftool: Work-around rst2man conversion bugAndrii Nakryiko1-7/+8
Work-around what appears to be a bug in rst2man convertion tool, used to create man pages out of reStructureText-formatted documents. If text line starts with dot, rst2man will put it in resulting man file verbatim. This seems to cause man tool to interpret it as a directive/command (e.g., `.bs`), and subsequently not render entire line because it's unrecognized one. Enclose '.xxx' words in extra formatting to work around. Fixes: cb21ac588546 ("bpftool: Add gen subcommand manpage") Reported-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yonghong Song <yhs@fb.com Link: https://lore.kernel.org/bpf/20191218221707.2552199-1-andriin@fb.com
2019-12-19bpftool: Simplify format string to not use positional argsAndrii Nakryiko1-2/+2
Change format string referring to just single argument out of two available. Some versions of libc can reject such format string. Reported-by: Nikita Shirokov <tehnerd@tehnerd.com> Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20191218214314.2403729-1-andriin@fb.com
2019-12-18Merge branch 'skel-fixes'Alexei Starovoitov12-155/+460
Andrii Nakryiko says: ==================== Simplify skeleton usage by embedding source BPF object file inside skeleton itself. This allows to keep skeleton and object file in sync at all times with no chance of confusion. Also, add bpftool-gen.rst manpage, explaining concepts and ideas behind skeleton. In examples section it also includes a complete small BPF application utilizing skeleton, as a demonstration of API. Patch #2 also removes BPF_EMBED_OBJ, as there is currently no use of it. v2->v3: - (void) in no-args function (Alexei); - bpftool-gen.rst code block formatting fix (Alexei); - simplified xxx__create_skeleton to fill in obj and return error code; v1->v2: - remove whitespace from empty lines in code blocks (Yonghong). ==================== Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2019-12-18bpftool: Add gen subcommand manpageAndrii Nakryiko2-1/+306
Add bpftool-gen.rst describing skeleton on the high level. Also include a small, but complete, example BPF app (BPF side, userspace side, generated skeleton) in example section to demonstrate skeleton API and its usage. Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20191218052552.2915188-4-andriin@fb.com
2019-12-18libbpf: Remove BPF_EMBED_OBJ macro from libbpf.hAndrii Nakryiko1-35/+0
Drop BPF_EMBED_OBJ and struct bpf_embed_data now that skeleton automatically embeds contents of its source object file. While BPF_EMBED_OBJ is useful independently of skeleton, we are currently don't have any use cases utilizing it, so let's remove them until/if we need it. Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20191218052552.2915188-3-andriin@fb.com
2019-12-18bpftool, selftests/bpf: Embed object file inside skeletonAndrii Nakryiko9-119/+154
Embed contents of BPF object file used for BPF skeleton generation inside skeleton itself. This allows to keep BPF object file and its skeleton in sync at all times, and simpifies skeleton instantiation. Also switch existing selftests to not require BPF_EMBED_OBJ anymore. Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20191218052552.2915188-2-andriin@fb.com
2019-12-18libbpf: Reduce log level for custom section namesAndrii Nakryiko1-3/+3
Libbpf is trying to recognize BPF program type based on its section name during bpf_object__open() phase. This is not strictly enforced and user code has ability to specify/override correct BPF program type after open. But if BPF program is using custom section name, libbpf will still emit warnings, which can be quite annoying to users. This patch reduces log level of information messages emitted by libbpf if section name is not canonical. User can still get a list of all supported section names as debug-level message. Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org> Link: https://lore.kernel.org/bpf/20191217234228.1739308-1-andriin@fb.com
2019-12-18libbpf: Fix libbpf_common.h when installing libbpf through 'make install'Toke Høiland-Jørgensen2-0/+3
This fixes two issues with the newly introduced libbpf_common.h file: - The header failed to include <string.h> for the definition of memset() - The new file was not included in the install_headers rule in the Makefile Both of these issues cause breakage when installing libbpf with 'make install' and trying to use it in applications. Fixes: 544402d4b493 ("libbpf: Extract common user-facing helpers") Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20191217112810.768078-1-toke@redhat.com