summaryrefslogtreecommitdiffstats
path: root/tools/lib/bpf/libbpf_util.h
Commit message (Collapse)AuthorAgeFilesLines
* libbpf: move logging helpers into libbpf_internal.hAndrii Nakryiko2019-05-161-13/+0Star
| | | | | | | | | | | | | libbpf_util.h header was recently exposed as public as a dependency of xsk.h. In addition to memory barriers, it contained logging helpers, which are not supposed to be exposed. This patch moves those into libbpf_internal.h, which is kept as an internal header. Cc: Stanislav Fomichev <sdf@google.com> Cc: Daniel Borkmann <daniel@iogearbox.net> Fixes: 7080da890984 ("libbpf: add libbpf_util.h to header install.") Signed-off-by: Andrii Nakryiko <andriin@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
* libbpf: remove compile time warning from libbpf_util.hMagnus Karlsson2019-04-191-1/+1
| | | | | | | | | | | Having a helpful compile time warning in libbpf_util.h is not a good idea since all warnings are treated as errors. Change this into a comment in the code instead. Fixes: b7e3a28019c9 ("libbpf: remove dependency on barrier.h in xsk.h") Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com> Acked-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
* libbpf: optimize barrier for XDP socket ringsMagnus Karlsson2019-04-171-0/+5
| | | | | | | | | | | | | | | | | | | The full memory barrier in the XDP socket rings on the consumer side between the load of the data and the store of the consumer ring is there to protect the store from being executed before the load of the data. If this was allowed to happen, the producer might overwrite the data field with a new entry before the consumer got the chance to read it. On x86, stores are guaranteed not to be reordered with older loads, so it does not need a full memory barrier here. A compile time barrier would be enough. This patch introdcues a new primitive in libbpf_util.h that implements a new barrier type (libbpf_smp_rwmb) hindering stores to be reordered with older loads. It is then used in the XDP socket ring access code in libbpf to improve performance. Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
* libbpf: remove dependency on barrier.h in xsk.hMagnus Karlsson2019-04-171-0/+25
| | | | | | | | | | | | | | The use of smp_rmb() and smp_wmb() creates a Linux header dependency on barrier.h that is unnecessary in most parts. This patch implements the two small defines that are needed from barrier.h. As a bonus, the new implementations are faster than the default ones as they default to sfence and lfence for x86, while we only need a compiler barrier in our case. Just as it is when the same ring access code is compiled in the kernel. Fixes: 1cad07884239 ("libbpf: add support for using AF_XDP sockets") Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
* tools/bpf: print out btf log at LIBBPF_WARN levelYonghong Song2019-02-041-2/+0Star
| | | | | | | | | | | | | | | | | | | | Currently, the btf log is allocated and printed out in case of error at LIBBPF_DEBUG level. Such logs from kernel are very important for debugging. For example, bpf syscall BPF_PROG_LOAD command can get verifier logs back to user space. In function load_program() of libbpf.c, the log buffer is allocated unconditionally and printed out at pr_warning() level. Let us do the similar thing here for btf. Allocate buffer unconditionally and print out error logs at pr_warning() level. This can reduce one global function and optimize for common situations where pr_warning() is activated either by default or by user supplied debug output function. Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>
* tools/bpf: move libbpf pr_* debug print functions to headersYonghong Song2019-02-041-0/+32
A global function libbpf_print, which is invisible outside the shared library, is defined to print based on levels. The pr_warning, pr_info and pr_debug macros are moved into the newly created header common.h. So any .c file including common.h can use these macros directly. Currently btf__new and btf_ext__new API has an argument getting __pr_debug function pointer into btf.c so the debugging information can be printed there. This patch removed this parameter from btf__new and btf_ext__new and directly using pr_debug in btf.c. Another global function libbpf_print_level_available, also invisible outside the shared library, can test whether a particular level debug printing is available or not. It is used in btf.c to test whether DEBUG level debug printing is availabl or not, based on which the log buffer will be allocated when loading btf to the kernel. Signed-off-by: Yonghong Song <yhs@fb.com> Signed-off-by: Alexei Starovoitov <ast@kernel.org>