Message ID | 20220603154028.24904-2-toke@redhat.com (mailing list archive) |
---|---|
State | Superseded |
Delegated to: | BPF |
Headers | show |
Series | [bpf,1/2] bpf: Fix calling global functions from BPF_PROG_TYPE_EXT programs | expand |
On Fri, Jun 3, 2022 at 11:01 AM Toke Høiland-Jørgensen <toke@redhat.com> wrote: > > Add a selftest that calls a global function with a context object parameter > from an freplace function to check that the program context type is > correctly converted to the freplace target when fetching the context type > from the kernel BTF. > > Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> > --- > .../selftests/bpf/prog_tests/fexit_bpf2bpf.c | 13 ++++++++++ > .../bpf/progs/freplace_global_func.c | 24 +++++++++++++++++++ > 2 files changed, 37 insertions(+) > create mode 100644 tools/testing/selftests/bpf/progs/freplace_global_func.c > > diff --git a/tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c b/tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c > index d9aad15e0d24..6e86a1d92e97 100644 > --- a/tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c > +++ b/tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c > @@ -395,6 +395,17 @@ static void test_func_map_prog_compatibility(void) > "./test_attach_probe.o"); > } > > +static void test_func_replace_global_func(void) > +{ > + const char *prog_name[] = { > + "freplace/test_pkt_access", > + }; > + test_fexit_bpf2bpf_common("./freplace_global_func.o", > + "./test_pkt_access.o", > + ARRAY_SIZE(prog_name), > + prog_name, false, NULL); > +} > + > /* NOTE: affect other tests, must run in serial mode */ > void serial_test_fexit_bpf2bpf(void) > { > @@ -416,4 +427,6 @@ void serial_test_fexit_bpf2bpf(void) > test_func_replace_multi(); > if (test__start_subtest("fmod_ret_freplace")) > test_fmod_ret_freplace(); > + if (test__start_subtest("func_replace_global_func")) > + test_func_replace_global_func(); > } > diff --git a/tools/testing/selftests/bpf/progs/freplace_global_func.c b/tools/testing/selftests/bpf/progs/freplace_global_func.c > new file mode 100644 > index 000000000000..d9f8276229cc > --- /dev/null > +++ b/tools/testing/selftests/bpf/progs/freplace_global_func.c > @@ -0,0 +1,24 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* Copyright (c) 2019 Facebook */ nit: I think you meant 2022, not 2019? :) > +#include <linux/stddef.h> > +#include <linux/bpf.h> > +#include <bpf/bpf_helpers.h> > +#include <bpf/bpf_endian.h> > +#include <bpf/bpf_tracing.h> nit: I think the only headers you need here are the linux/bpf.h and bpf/bpf_helpers.h ones. > + > +__attribute__ ((noinline)) > +int test_ctx_global_func(struct __sk_buff *skb) > +{ > + volatile int retval = 1; > + return retval; > +} > + > +__u64 test_pkt_access_global_func = 0; > +SEC("freplace/test_pkt_access") > +int new_test_pkt_access(struct __sk_buff *skb) > +{ > + test_pkt_access_global_func = test_ctx_global_func(skb); > + return -1; > +} > + > +char _license[] SEC("license") = "GPL"; > -- > 2.36.1 >
On Fri, Jun 3, 2022 at 8:42 AM Toke Høiland-Jørgensen <toke@redhat.com> wrote: > > Add a selftest that calls a global function with a context object parameter > from an freplace function to check that the program context type is > correctly converted to the freplace target when fetching the context type > from the kernel BTF. > > Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> > --- > .../selftests/bpf/prog_tests/fexit_bpf2bpf.c | 13 ++++++++++ > .../bpf/progs/freplace_global_func.c | 24 +++++++++++++++++++ > 2 files changed, 37 insertions(+) > create mode 100644 tools/testing/selftests/bpf/progs/freplace_global_func.c > > diff --git a/tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c b/tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c > index d9aad15e0d24..6e86a1d92e97 100644 > --- a/tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c > +++ b/tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c > @@ -395,6 +395,17 @@ static void test_func_map_prog_compatibility(void) > "./test_attach_probe.o"); > } > > +static void test_func_replace_global_func(void) > +{ > + const char *prog_name[] = { > + "freplace/test_pkt_access", > + }; empty line between variables and statements > + test_fexit_bpf2bpf_common("./freplace_global_func.o", > + "./test_pkt_access.o", > + ARRAY_SIZE(prog_name), > + prog_name, false, NULL); > +} > + > /* NOTE: affect other tests, must run in serial mode */ > void serial_test_fexit_bpf2bpf(void) > { > @@ -416,4 +427,6 @@ void serial_test_fexit_bpf2bpf(void) > test_func_replace_multi(); > if (test__start_subtest("fmod_ret_freplace")) > test_fmod_ret_freplace(); > + if (test__start_subtest("func_replace_global_func")) > + test_func_replace_global_func(); > } > diff --git a/tools/testing/selftests/bpf/progs/freplace_global_func.c b/tools/testing/selftests/bpf/progs/freplace_global_func.c > new file mode 100644 > index 000000000000..d9f8276229cc > --- /dev/null > +++ b/tools/testing/selftests/bpf/progs/freplace_global_func.c > @@ -0,0 +1,24 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* Copyright (c) 2019 Facebook */ > +#include <linux/stddef.h> > +#include <linux/bpf.h> > +#include <bpf/bpf_helpers.h> > +#include <bpf/bpf_endian.h> > +#include <bpf/bpf_tracing.h> > + > +__attribute__ ((noinline)) __noinline > +int test_ctx_global_func(struct __sk_buff *skb) > +{ > + volatile int retval = 1; > + return retval; just curious, why volatile instead of direct `return 1;`? Also, empty line between variable and return. > +} > + > +__u64 test_pkt_access_global_func = 0; nit: it's a variable, please put it at the top before functions, or at the very least add empty line between it and SEC() > +SEC("freplace/test_pkt_access") > +int new_test_pkt_access(struct __sk_buff *skb) > +{ > + test_pkt_access_global_func = test_ctx_global_func(skb); > + return -1; > +} > + > +char _license[] SEC("license") = "GPL"; > -- > 2.36.1 >
Andrii Nakryiko <andrii.nakryiko@gmail.com> writes: > On Fri, Jun 3, 2022 at 8:42 AM Toke Høiland-Jørgensen <toke@redhat.com> wrote: >> >> Add a selftest that calls a global function with a context object parameter >> from an freplace function to check that the program context type is >> correctly converted to the freplace target when fetching the context type >> from the kernel BTF. >> >> Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> >> --- >> .../selftests/bpf/prog_tests/fexit_bpf2bpf.c | 13 ++++++++++ >> .../bpf/progs/freplace_global_func.c | 24 +++++++++++++++++++ >> 2 files changed, 37 insertions(+) >> create mode 100644 tools/testing/selftests/bpf/progs/freplace_global_func.c >> >> diff --git a/tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c b/tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c >> index d9aad15e0d24..6e86a1d92e97 100644 >> --- a/tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c >> +++ b/tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c >> @@ -395,6 +395,17 @@ static void test_func_map_prog_compatibility(void) >> "./test_attach_probe.o"); >> } >> >> +static void test_func_replace_global_func(void) >> +{ >> + const char *prog_name[] = { >> + "freplace/test_pkt_access", >> + }; > > empty line between variables and statements > >> + test_fexit_bpf2bpf_common("./freplace_global_func.o", >> + "./test_pkt_access.o", >> + ARRAY_SIZE(prog_name), >> + prog_name, false, NULL); >> +} >> + >> /* NOTE: affect other tests, must run in serial mode */ >> void serial_test_fexit_bpf2bpf(void) >> { >> @@ -416,4 +427,6 @@ void serial_test_fexit_bpf2bpf(void) >> test_func_replace_multi(); >> if (test__start_subtest("fmod_ret_freplace")) >> test_fmod_ret_freplace(); >> + if (test__start_subtest("func_replace_global_func")) >> + test_func_replace_global_func(); >> } >> diff --git a/tools/testing/selftests/bpf/progs/freplace_global_func.c b/tools/testing/selftests/bpf/progs/freplace_global_func.c >> new file mode 100644 >> index 000000000000..d9f8276229cc >> --- /dev/null >> +++ b/tools/testing/selftests/bpf/progs/freplace_global_func.c >> @@ -0,0 +1,24 @@ >> +// SPDX-License-Identifier: GPL-2.0 >> +/* Copyright (c) 2019 Facebook */ >> +#include <linux/stddef.h> >> +#include <linux/bpf.h> >> +#include <bpf/bpf_helpers.h> >> +#include <bpf/bpf_endian.h> >> +#include <bpf/bpf_tracing.h> >> + >> +__attribute__ ((noinline)) > > __noinline > >> +int test_ctx_global_func(struct __sk_buff *skb) >> +{ >> + volatile int retval = 1; >> + return retval; > > just curious, why volatile instead of direct `return 1;`? Also, empty > line between variable and return. To prevent the compiler from optimising away the whole thing. I was actually under the impression that it shouldn't do that for global functions, but, well, it does and the 'volatile' keeps it from doing so... Will fix the other nits and resubmit. -Toke
diff --git a/tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c b/tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c index d9aad15e0d24..6e86a1d92e97 100644 --- a/tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c +++ b/tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c @@ -395,6 +395,17 @@ static void test_func_map_prog_compatibility(void) "./test_attach_probe.o"); } +static void test_func_replace_global_func(void) +{ + const char *prog_name[] = { + "freplace/test_pkt_access", + }; + test_fexit_bpf2bpf_common("./freplace_global_func.o", + "./test_pkt_access.o", + ARRAY_SIZE(prog_name), + prog_name, false, NULL); +} + /* NOTE: affect other tests, must run in serial mode */ void serial_test_fexit_bpf2bpf(void) { @@ -416,4 +427,6 @@ void serial_test_fexit_bpf2bpf(void) test_func_replace_multi(); if (test__start_subtest("fmod_ret_freplace")) test_fmod_ret_freplace(); + if (test__start_subtest("func_replace_global_func")) + test_func_replace_global_func(); } diff --git a/tools/testing/selftests/bpf/progs/freplace_global_func.c b/tools/testing/selftests/bpf/progs/freplace_global_func.c new file mode 100644 index 000000000000..d9f8276229cc --- /dev/null +++ b/tools/testing/selftests/bpf/progs/freplace_global_func.c @@ -0,0 +1,24 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2019 Facebook */ +#include <linux/stddef.h> +#include <linux/bpf.h> +#include <bpf/bpf_helpers.h> +#include <bpf/bpf_endian.h> +#include <bpf/bpf_tracing.h> + +__attribute__ ((noinline)) +int test_ctx_global_func(struct __sk_buff *skb) +{ + volatile int retval = 1; + return retval; +} + +__u64 test_pkt_access_global_func = 0; +SEC("freplace/test_pkt_access") +int new_test_pkt_access(struct __sk_buff *skb) +{ + test_pkt_access_global_func = test_ctx_global_func(skb); + return -1; +} + +char _license[] SEC("license") = "GPL";
Add a selftest that calls a global function with a context object parameter from an freplace function to check that the program context type is correctly converted to the freplace target when fetching the context type from the kernel BTF. Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com> --- .../selftests/bpf/prog_tests/fexit_bpf2bpf.c | 13 ++++++++++ .../bpf/progs/freplace_global_func.c | 24 +++++++++++++++++++ 2 files changed, 37 insertions(+) create mode 100644 tools/testing/selftests/bpf/progs/freplace_global_func.c