From 0ac01febd4753809d7d4d785f71cac2abde6b1c3 Mon Sep 17 00:00:00 2001 From: Ira Weiny Date: Tue, 19 Mar 2019 14:11:49 -0700 Subject: BPF: Add sample code for new ib_umad tracepoint Provide a count of class types for a summary of MAD packets. The example shows one way to filter the trace data based on management class. Signed-off-by: Ira Weiny Signed-off-by: Jason Gunthorpe --- samples/bpf/ibumad_kern.c | 144 ++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 144 insertions(+) create mode 100644 samples/bpf/ibumad_kern.c (limited to 'samples/bpf/ibumad_kern.c') diff --git a/samples/bpf/ibumad_kern.c b/samples/bpf/ibumad_kern.c new file mode 100644 index 000000000000..38b2b3f22049 --- /dev/null +++ b/samples/bpf/ibumad_kern.c @@ -0,0 +1,144 @@ +// SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB + +/** + * ibumad BPF sample kernel side + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of version 2 of the GNU General Public + * License as published by the Free Software Foundation. + * + * Copyright(c) 2018 Ira Weiny, Intel Corporation + */ + +#define KBUILD_MODNAME "ibumad_count_pkts_by_class" +#include + +#include "bpf_helpers.h" + + +struct bpf_map_def SEC("maps") read_count = { + .type = BPF_MAP_TYPE_ARRAY, + .key_size = sizeof(u32), /* class; u32 required */ + .value_size = sizeof(u64), /* count of mads read */ + .max_entries = 256, /* Room for all Classes */ +}; + +struct bpf_map_def SEC("maps") write_count = { + .type = BPF_MAP_TYPE_ARRAY, + .key_size = sizeof(u32), /* class; u32 required */ + .value_size = sizeof(u64), /* count of mads written */ + .max_entries = 256, /* Room for all Classes */ +}; + +#undef DEBUG +#ifdef DEBUG +#define bpf_debug(fmt, ...) \ +({ \ + char ____fmt[] = fmt; \ + bpf_trace_printk(____fmt, sizeof(____fmt), \ + ##__VA_ARGS__); \ +}) +#else +#define bpf_debug(fmt, ...) +#endif + +/* Taken from the current format defined in + * include/trace/events/ib_umad.h + * and + * /sys/kernel/debug/tracing/events/ib_umad/ib_umad_read/format + * /sys/kernel/debug/tracing/events/ib_umad/ib_umad_write/format + */ +struct ib_umad_rw_args { + u64 pad; + u8 port_num; + u8 sl; + u8 path_bits; + u8 grh_present; + u32 id; + u32 status; + u32 timeout_ms; + u32 retires; + u32 length; + u32 qpn; + u32 qkey; + u8 gid_index; + u8 hop_limit; + u16 lid; + u16 attr_id; + u16 pkey_index; + u8 base_version; + u8 mgmt_class; + u8 class_version; + u8 method; + u32 flow_label; + u16 mad_status; + u16 class_specific; + u32 attr_mod; + u64 tid; + u8 gid[16]; + u32 dev_index; + u8 traffic_class; +}; + +SEC("tracepoint/ib_umad/ib_umad_read_recv") +int on_ib_umad_read_recv(struct ib_umad_rw_args *ctx) +{ + u64 zero = 0, *val; + u8 class = ctx->mgmt_class; + + bpf_debug("ib_umad read recv : class 0x%x\n", class); + + val = bpf_map_lookup_elem(&read_count, &class); + if (!val) { + bpf_map_update_elem(&read_count, &class, &zero, BPF_NOEXIST); + val = bpf_map_lookup_elem(&read_count, &class); + if (!val) + return 0; + } + + (*val) += 1; + + return 0; +} +SEC("tracepoint/ib_umad/ib_umad_read_send") +int on_ib_umad_read_send(struct ib_umad_rw_args *ctx) +{ + u64 zero = 0, *val; + u8 class = ctx->mgmt_class; + + bpf_debug("ib_umad read send : class 0x%x\n", class); + + val = bpf_map_lookup_elem(&read_count, &class); + if (!val) { + bpf_map_update_elem(&read_count, &class, &zero, BPF_NOEXIST); + val = bpf_map_lookup_elem(&read_count, &class); + if (!val) + return 0; + } + + (*val) += 1; + + return 0; +} +SEC("tracepoint/ib_umad/ib_umad_write") +int on_ib_umad_write(struct ib_umad_rw_args *ctx) +{ + u64 zero = 0, *val; + u8 class = ctx->mgmt_class; + + bpf_debug("ib_umad write : class 0x%x\n", class); + + val = bpf_map_lookup_elem(&write_count, &class); + if (!val) { + bpf_map_update_elem(&write_count, &class, &zero, BPF_NOEXIST); + val = bpf_map_lookup_elem(&write_count, &class); + if (!val) + return 0; + } + + (*val) += 1; + + return 0; +} + +char _license[] SEC("license") = "GPL"; -- cgit v1.2.3-55-g7522