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-rw-r--r--samples/bpf/tracex3_kern.c90
1 files changed, 0 insertions, 90 deletions
diff --git a/samples/bpf/tracex3_kern.c b/samples/bpf/tracex3_kern.c
deleted file mode 100644
index bde6591cb20c..000000000000
--- a/samples/bpf/tracex3_kern.c
+++ /dev/null
@@ -1,90 +0,0 @@
-/* Copyright (c) 2013-2015 PLUMgrid, http://plumgrid.com
- *
- * 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.
- */
-#include <linux/skbuff.h>
-#include <linux/netdevice.h>
-#include <linux/version.h>
-#include <uapi/linux/bpf.h>
-#include <bpf/bpf_helpers.h>
-#include <bpf/bpf_tracing.h>
-
-struct {
- __uint(type, BPF_MAP_TYPE_HASH);
- __type(key, long);
- __type(value, u64);
- __uint(max_entries, 4096);
-} my_map SEC(".maps");
-
-/* kprobe is NOT a stable ABI. If kernel internals change this bpf+kprobe
- * example will no longer be meaningful
- */
-SEC("kprobe/blk_mq_start_request")
-int bpf_prog1(struct pt_regs *ctx)
-{
- long rq = PT_REGS_PARM1(ctx);
- u64 val = bpf_ktime_get_ns();
-
- bpf_map_update_elem(&my_map, &rq, &val, BPF_ANY);
- return 0;
-}
-
-static unsigned int log2l(unsigned long long n)
-{
-#define S(k) if (n >= (1ull << k)) { i += k; n >>= k; }
- int i = -(n == 0);
- S(32); S(16); S(8); S(4); S(2); S(1);
- return i;
-#undef S
-}
-
-#define SLOTS 100
-
-struct {
- __uint(type, BPF_MAP_TYPE_PERCPU_ARRAY);
- __uint(key_size, sizeof(u32));
- __uint(value_size, sizeof(u64));
- __uint(max_entries, SLOTS);
-} lat_map SEC(".maps");
-
-SEC("kprobe/__blk_account_io_done")
-int bpf_prog2(struct pt_regs *ctx)
-{
- long rq = PT_REGS_PARM1(ctx);
- u64 *value, l, base;
- u32 index;
-
- value = bpf_map_lookup_elem(&my_map, &rq);
- if (!value)
- return 0;
-
- u64 cur_time = bpf_ktime_get_ns();
- u64 delta = cur_time - *value;
-
- bpf_map_delete_elem(&my_map, &rq);
-
- /* the lines below are computing index = log10(delta)*10
- * using integer arithmetic
- * index = 29 ~ 1 usec
- * index = 59 ~ 1 msec
- * index = 89 ~ 1 sec
- * index = 99 ~ 10sec or more
- * log10(x)*10 = log2(x)*10/log2(10) = log2(x)*3
- */
- l = log2l(delta);
- base = 1ll << l;
- index = (l * 64 + (delta - base) * 64 / base) * 3 / 64;
-
- if (index >= SLOTS)
- index = SLOTS - 1;
-
- value = bpf_map_lookup_elem(&lat_map, &index);
- if (value)
- *value += 1;
-
- return 0;
-}
-char _license[] SEC("license") = "GPL";
-u32 _version SEC("version") = LINUX_VERSION_CODE;