kernel-ark/samples/bpf/ibumad_kern.c
Ira Weiny 0ac01febd4 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 <ira.weiny@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
2019-03-27 15:53:26 -03:00

145 lines
3.2 KiB
C

// 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 <uapi/linux/bpf.h>
#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";