kernel/bpf-developer-tutorial
1
0
Fork 0
mirror of https://github.com/eunomia-bpf/bpf-developer-tutorial.git synced 2026-02-05 19:24:04 +08:00
Code Issues Packages Projects Releases Wiki Activity

add

Browse Source
This commit is contained in:
yunwei37
2024-12-02 08:20:12 +00:00
parent 1696b2b559
commit e6c0489187
3 changed files with 28 additions and 5 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2
src/43-kfuncs/module/Makefile
View File

@@ -2,7 +2,7 @@ obj-m += hello.o # hello.o is the target
# Enable BTF generation
KBUILD_CFLAGS += -g -O2
ccflags-y += -DCONFIG_BPF_SYSCALL
all:
# Compile the module with BTF information
make -C /lib/modules/$(shell uname -r)/build M=$(PWD) modules

27
src/43-kfuncs/module/hello.c
View File

@@ -4,15 +4,32 @@
#include <linux/bpf.h>
#include <linux/btf.h>
#include <linux/btf_ids.h>
// #include <linux/bpf_trace.h> // Add this include
__bpf_kfunc int bpf_strstr(const char *str, u32 str__sz, const char *substr, u32 substr__sz);
__bpf_kfunc int bpf_xdp_runner(struct xdp_md *ctx);
/* Define a kfunc function */
__bpf_kfunc_start_defs();
// Remove or comment out this line:
// extern u64 bpf_trace_printk(u64 fmt, u64 fmt_size, u64 arg1, u64 arg2, u64 arg3);
// EXPORT_SYMBOL_GPL(bpf_trace_printk);
__bpf_kfunc int bpf_strstr(const char *str, u32 str__sz, const char *substr, u32 substr__sz)
{
// Edge case: if substr is empty, return 0 (assuming empty string is found at the start)
// const char *fmt = "strstr: str=%s, str__sz=%u, substr=%s\n";
// // bpf_trace_printk((u64)(void*)fmt, (u64)sizeof(fmt), (u64)(void*)str, (u64)str__sz, (u64)(void*)substr);
// // Edge case: if substr is empty, return 0 (assuming empty string is found at the start)
// const struct bpf_func_proto *proto = bpf_base_func_proto(BPF_FUNC_trace_printk, NULL);
// if (!proto) {
// pr_err("bpf_trace_printk: Failed to get prototype\n");
// return -1;
// }
// if (proto->func) {
// proto->func((u64)(void*)fmt, (u64)sizeof(fmt), (u64)(void*)str, str__sz, (u64)(void*)substr);
// } else {
// pr_err("bpf_trace_printk: Failed to get function pointer\n");
// }
if (substr__sz == 0)
{
return 0;
@@ -42,10 +59,16 @@ __bpf_kfunc int bpf_strstr(const char *str, u32 str__sz, const char *substr, u32
return -1;
}
__bpf_kfunc int bpf_xdp_runner(struct xdp_md *ctx) {
return XDP_PASS;
}
__bpf_kfunc_end_defs();
BTF_KFUNCS_START(bpf_kfunc_example_ids_set)
BTF_ID_FLAGS(func, bpf_strstr)
BTF_ID_FLAGS(func, bpf_xdp_runner)
BTF_KFUNCS_END(bpf_kfunc_example_ids_set)
// Register the kfunc ID set

4
src/46-xdp-test/xdp-pktgen.bpf.c
View File

@@ -6,7 +6,7 @@
char _license[] SEC("license") = "GPL";
SEC("xdp")
int xdp_redirect_notouch(struct xdp_md *ctx)
int xdp_pass(struct xdp_md *ctx)
{
return XDP_TX;
return XDP_PASS;
}