linux-stable/samples/bpf/ibumad_kern.c
Ross Zwisler 27d7fdf06f bpf: use canonical ftrace path
The canonical location for the tracefs filesystem is at /sys/kernel/tracing.

But, from Documentation/trace/ftrace.rst:

  Before 4.1, all ftrace tracing control files were within the debugfs
  file system, which is typically located at /sys/kernel/debug/tracing.
  For backward compatibility, when mounting the debugfs file system,
  the tracefs file system will be automatically mounted at:

  /sys/kernel/debug/tracing

Many comments and samples in the bpf code still refer to this older
debugfs path, so let's update them to avoid confusion.  There are a few
spots where the bpf code explicitly checks both tracefs and debugfs
(tools/bpf/bpftool/tracelog.c and tools/lib/api/fs/fs.c) and I've left
those alone so that the tools can continue to work with both paths.

Signed-off-by: Ross Zwisler <zwisler@google.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Link: https://lore.kernel.org/r/20230313205628.1058720-2-zwisler@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2023-03-13 21:51:30 -07:00

138 lines
2.9 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/bpf_helpers.h>
struct {
__uint(type, BPF_MAP_TYPE_ARRAY);
__type(key, u32); /* class; u32 required */
__type(value, u64); /* count of mads read */
__uint(max_entries, 256); /* Room for all Classes */
} read_count SEC(".maps");
struct {
__uint(type, BPF_MAP_TYPE_ARRAY);
__type(key, u32); /* class; u32 required */
__type(value, u64); /* count of mads written */
__uint(max_entries, 256); /* Room for all Classes */
} write_count SEC(".maps");
#undef DEBUG
#ifndef DEBUG
#undef bpf_printk
#define bpf_printk(fmt, ...)
#endif
/* Taken from the current format defined in
* include/trace/events/ib_umad.h
* and
* /sys/kernel/tracing/events/ib_umad/ib_umad_read/format
* /sys/kernel/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_printk("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_printk("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_printk("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";