| Message ID | 20210116182133.2286884-3-qais.yousef@arm.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | BPF |
| Headers | show |
| Series | Allow attaching to bare tracepoints | expand |
On 1/16/21 10:21 AM, Qais Yousef wrote: > Reuse module_attach infrastructure to add a new bare tracepoint to check > we can attach to it as a raw tracepoint. > > Signed-off-by: Qais Yousef <qais.yousef@arm.com> > --- > .../bpf/bpf_testmod/bpf_testmod-events.h | 6 +++++ > .../selftests/bpf/bpf_testmod/bpf_testmod.c | 21 ++++++++++++++- > .../selftests/bpf/bpf_testmod/bpf_testmod.h | 6 +++++ > .../selftests/bpf/prog_tests/module_attach.c | 27 +++++++++++++++++++ > .../selftests/bpf/progs/test_module_attach.c | 10 +++++++ > 5 files changed, 69 insertions(+), 1 deletion(-) > > diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod-events.h b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod-events.h > index b83ea448bc79..89c6d58e5dd6 100644 > --- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod-events.h > +++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod-events.h > @@ -28,6 +28,12 @@ TRACE_EVENT(bpf_testmod_test_read, > __entry->pid, __entry->comm, __entry->off, __entry->len) > ); > > +/* A bare tracepoint with no event associated with it */ > +DECLARE_TRACE(bpf_testmod_test_write_bare, > + TP_PROTO(struct task_struct *task, struct bpf_testmod_test_write_ctx *ctx), > + TP_ARGS(task, ctx) > +); > + > #endif /* _BPF_TESTMOD_EVENTS_H */ > > #undef TRACE_INCLUDE_PATH > diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c > index 2df19d73ca49..e900adad2276 100644 > --- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c > +++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c > @@ -28,9 +28,28 @@ bpf_testmod_test_read(struct file *file, struct kobject *kobj, > EXPORT_SYMBOL(bpf_testmod_test_read); > ALLOW_ERROR_INJECTION(bpf_testmod_test_read, ERRNO); > > +noinline ssize_t > +bpf_testmod_test_write(struct file *file, struct kobject *kobj, > + struct bin_attribute *bin_attr, > + char *buf, loff_t off, size_t len) > +{ > + struct bpf_testmod_test_write_ctx ctx = { > + .buf = buf, > + .off = off, > + .len = len, > + }; > + > + trace_bpf_testmod_test_write_bare(current, &ctx); > + > + return -EIO; /* always fail */ > +} > +EXPORT_SYMBOL(bpf_testmod_test_write); > +ALLOW_ERROR_INJECTION(bpf_testmod_test_write, ERRNO); > + > static struct bin_attribute bin_attr_bpf_testmod_file __ro_after_init = { Do we need to remove __ro_after_init? > - .attr = { .name = "bpf_testmod", .mode = 0444, }, > + .attr = { .name = "bpf_testmod", .mode = 0666, }, > .read = bpf_testmod_test_read, > + .write = bpf_testmod_test_write, > }; > > static int bpf_testmod_init(void) > diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.h b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.h > index b81adfedb4f6..b3892dc40111 100644 > --- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.h > +++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.h > @@ -11,4 +11,10 @@ struct bpf_testmod_test_read_ctx { > size_t len; > }; > > +struct bpf_testmod_test_write_ctx { > + char *buf; > + loff_t off; > + size_t len; > +}; > + > #endif /* _BPF_TESTMOD_H */ > diff --git a/tools/testing/selftests/bpf/prog_tests/module_attach.c b/tools/testing/selftests/bpf/prog_tests/module_attach.c > index 50796b651f72..e4605c0b5af1 100644 > --- a/tools/testing/selftests/bpf/prog_tests/module_attach.c > +++ b/tools/testing/selftests/bpf/prog_tests/module_attach.c > @@ -21,9 +21,34 @@ static int trigger_module_test_read(int read_sz) > return 0; > } > > +static int trigger_module_test_write(int write_sz) > +{ > + int fd, err; Init err = 0? > + char *buf = malloc(write_sz); > + > + if (!buf) > + return -ENOMEM; Looks like we already non-negative value, so return ENOMEM? > + > + memset(buf, 'a', write_sz); > + buf[write_sz-1] = '\0'; > + > + fd = open("/sys/kernel/bpf_testmod", O_WRONLY); > + err = -errno; > + if (CHECK(fd < 0, "testmod_file_open", "failed: %d\n", err)) > + goto out; Change the above to fd = open("/sys/kernel/bpf_testmod", O_WRONLY); if (CHECK(fd < 0, "testmod_file_open", "failed: %d\n", errno)) { err = -errno; goto out; } > + > + write(fd, buf, write_sz); > + close(fd); > +out: > + free(buf); > + No need for extra line here. > + return 0; return err. > +} > + > void test_module_attach(void) > { > const int READ_SZ = 456; > + const int WRITE_SZ = 457; > struct test_module_attach* skel; > struct test_module_attach__bss *bss; > int err; > @@ -48,8 +73,10 @@ void test_module_attach(void) > > /* trigger tracepoint */ > ASSERT_OK(trigger_module_test_read(READ_SZ), "trigger_read"); > + ASSERT_OK(trigger_module_test_write(WRITE_SZ), "trigger_write"); > > ASSERT_EQ(bss->raw_tp_read_sz, READ_SZ, "raw_tp"); > + ASSERT_EQ(bss->raw_tp_bare_write_sz, WRITE_SZ, "raw_tp_bare"); > ASSERT_EQ(bss->tp_btf_read_sz, READ_SZ, "tp_btf"); > ASSERT_EQ(bss->fentry_read_sz, READ_SZ, "fentry"); > ASSERT_EQ(bss->fentry_manual_read_sz, READ_SZ, "fentry_manual"); > diff --git a/tools/testing/selftests/bpf/progs/test_module_attach.c b/tools/testing/selftests/bpf/progs/test_module_attach.c > index efd1e287ac17..bd37ceec5587 100644 > --- a/tools/testing/selftests/bpf/progs/test_module_attach.c > +++ b/tools/testing/selftests/bpf/progs/test_module_attach.c > @@ -17,6 +17,16 @@ int BPF_PROG(handle_raw_tp, > return 0; > } > > +__u32 raw_tp_bare_write_sz = 0; > + > +SEC("raw_tp/bpf_testmod_test_write_bare") > +int BPF_PROG(handle_raw_tp_bare, > + struct task_struct *task, struct bpf_testmod_test_write_ctx *write_ctx) > +{ > + raw_tp_bare_write_sz = BPF_CORE_READ(write_ctx, len); > + return 0; > +} > + > __u32 tp_btf_read_sz = 0; > > SEC("tp_btf/bpf_testmod_test_read") >
On 01/16/21 18:11, Yonghong Song wrote: > > > On 1/16/21 10:21 AM, Qais Yousef wrote: > > Reuse module_attach infrastructure to add a new bare tracepoint to check > > we can attach to it as a raw tracepoint. > > > > Signed-off-by: Qais Yousef <qais.yousef@arm.com> > > --- > > .../bpf/bpf_testmod/bpf_testmod-events.h | 6 +++++ > > .../selftests/bpf/bpf_testmod/bpf_testmod.c | 21 ++++++++++++++- > > .../selftests/bpf/bpf_testmod/bpf_testmod.h | 6 +++++ > > .../selftests/bpf/prog_tests/module_attach.c | 27 +++++++++++++++++++ > > .../selftests/bpf/progs/test_module_attach.c | 10 +++++++ > > 5 files changed, 69 insertions(+), 1 deletion(-) > > > > diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod-events.h b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod-events.h > > index b83ea448bc79..89c6d58e5dd6 100644 > > --- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod-events.h > > +++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod-events.h > > @@ -28,6 +28,12 @@ TRACE_EVENT(bpf_testmod_test_read, > > __entry->pid, __entry->comm, __entry->off, __entry->len) > > ); > > +/* A bare tracepoint with no event associated with it */ > > +DECLARE_TRACE(bpf_testmod_test_write_bare, > > + TP_PROTO(struct task_struct *task, struct bpf_testmod_test_write_ctx *ctx), > > + TP_ARGS(task, ctx) > > +); > > + > > #endif /* _BPF_TESTMOD_EVENTS_H */ > > #undef TRACE_INCLUDE_PATH > > diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c > > index 2df19d73ca49..e900adad2276 100644 > > --- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c > > +++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c > > @@ -28,9 +28,28 @@ bpf_testmod_test_read(struct file *file, struct kobject *kobj, > > EXPORT_SYMBOL(bpf_testmod_test_read); > > ALLOW_ERROR_INJECTION(bpf_testmod_test_read, ERRNO); > > +noinline ssize_t > > +bpf_testmod_test_write(struct file *file, struct kobject *kobj, > > + struct bin_attribute *bin_attr, > > + char *buf, loff_t off, size_t len) > > +{ > > + struct bpf_testmod_test_write_ctx ctx = { > > + .buf = buf, > > + .off = off, > > + .len = len, > > + }; > > + > > + trace_bpf_testmod_test_write_bare(current, &ctx); > > + > > + return -EIO; /* always fail */ > > +} > > +EXPORT_SYMBOL(bpf_testmod_test_write); > > +ALLOW_ERROR_INJECTION(bpf_testmod_test_write, ERRNO); > > + > > static struct bin_attribute bin_attr_bpf_testmod_file __ro_after_init = { > > Do we need to remove __ro_after_init? I don't think so. The structure should still remain RO AFAIU. > > > - .attr = { .name = "bpf_testmod", .mode = 0444, }, > > + .attr = { .name = "bpf_testmod", .mode = 0666, }, > > .read = bpf_testmod_test_read, > > + .write = bpf_testmod_test_write, > > }; > > static int bpf_testmod_init(void) > > diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.h b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.h > > index b81adfedb4f6..b3892dc40111 100644 > > --- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.h > > +++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.h > > @@ -11,4 +11,10 @@ struct bpf_testmod_test_read_ctx { > > size_t len; > > }; > > +struct bpf_testmod_test_write_ctx { > > + char *buf; > > + loff_t off; > > + size_t len; > > +}; > > + > > #endif /* _BPF_TESTMOD_H */ > > diff --git a/tools/testing/selftests/bpf/prog_tests/module_attach.c b/tools/testing/selftests/bpf/prog_tests/module_attach.c > > index 50796b651f72..e4605c0b5af1 100644 > > --- a/tools/testing/selftests/bpf/prog_tests/module_attach.c > > +++ b/tools/testing/selftests/bpf/prog_tests/module_attach.c > > @@ -21,9 +21,34 @@ static int trigger_module_test_read(int read_sz) > > return 0; > > } > > +static int trigger_module_test_write(int write_sz) > > +{ > > + int fd, err; > > Init err = 0? I don't see what difference this makes. > > > + char *buf = malloc(write_sz); > > + > > + if (!buf) > > + return -ENOMEM; > > Looks like we already non-negative value, so return ENOMEM? We already set err=-errno. So shouldn't we return negative too? > > > + > > + memset(buf, 'a', write_sz); > > + buf[write_sz-1] = '\0'; > > + > > + fd = open("/sys/kernel/bpf_testmod", O_WRONLY); > > + err = -errno; > > + if (CHECK(fd < 0, "testmod_file_open", "failed: %d\n", err)) > > + goto out; > > Change the above to > fd = open("/sys/kernel/bpf_testmod", O_WRONLY); > if (CHECK(fd < 0, "testmod_file_open", "failed: %d\n", errno)) { > err = -errno; > goto out; > } I kept the code consistent with the definition of trigger_module_test_read(). I'll leave it up to the maintainer to pick up the style changes if they prefer it this way. Thanks for the ack and for the review. Cheers -- Qais Yousef
On 1/18/21 4:18 AM, Qais Yousef wrote: > On 01/16/21 18:11, Yonghong Song wrote: >> >> >> On 1/16/21 10:21 AM, Qais Yousef wrote: >>> Reuse module_attach infrastructure to add a new bare tracepoint to check >>> we can attach to it as a raw tracepoint. >>> >>> Signed-off-by: Qais Yousef <qais.yousef@arm.com> >>> --- >>> .../bpf/bpf_testmod/bpf_testmod-events.h | 6 +++++ >>> .../selftests/bpf/bpf_testmod/bpf_testmod.c | 21 ++++++++++++++- >>> .../selftests/bpf/bpf_testmod/bpf_testmod.h | 6 +++++ >>> .../selftests/bpf/prog_tests/module_attach.c | 27 +++++++++++++++++++ >>> .../selftests/bpf/progs/test_module_attach.c | 10 +++++++ >>> 5 files changed, 69 insertions(+), 1 deletion(-) >>> >>> diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod-events.h b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod-events.h >>> index b83ea448bc79..89c6d58e5dd6 100644 >>> --- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod-events.h >>> +++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod-events.h >>> @@ -28,6 +28,12 @@ TRACE_EVENT(bpf_testmod_test_read, >>> __entry->pid, __entry->comm, __entry->off, __entry->len) >>> ); >>> +/* A bare tracepoint with no event associated with it */ >>> +DECLARE_TRACE(bpf_testmod_test_write_bare, >>> + TP_PROTO(struct task_struct *task, struct bpf_testmod_test_write_ctx *ctx), >>> + TP_ARGS(task, ctx) >>> +); >>> + >>> #endif /* _BPF_TESTMOD_EVENTS_H */ >>> #undef TRACE_INCLUDE_PATH >>> diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c >>> index 2df19d73ca49..e900adad2276 100644 >>> --- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c >>> +++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c >>> @@ -28,9 +28,28 @@ bpf_testmod_test_read(struct file *file, struct kobject *kobj, >>> EXPORT_SYMBOL(bpf_testmod_test_read); >>> ALLOW_ERROR_INJECTION(bpf_testmod_test_read, ERRNO); >>> +noinline ssize_t >>> +bpf_testmod_test_write(struct file *file, struct kobject *kobj, >>> + struct bin_attribute *bin_attr, >>> + char *buf, loff_t off, size_t len) >>> +{ >>> + struct bpf_testmod_test_write_ctx ctx = { >>> + .buf = buf, >>> + .off = off, >>> + .len = len, >>> + }; >>> + >>> + trace_bpf_testmod_test_write_bare(current, &ctx); >>> + >>> + return -EIO; /* always fail */ >>> +} >>> +EXPORT_SYMBOL(bpf_testmod_test_write); >>> +ALLOW_ERROR_INJECTION(bpf_testmod_test_write, ERRNO); >>> + >>> static struct bin_attribute bin_attr_bpf_testmod_file __ro_after_init = { >> >> Do we need to remove __ro_after_init? > > I don't think so. The structure should still remain RO AFAIU. okay. > >> >>> - .attr = { .name = "bpf_testmod", .mode = 0444, }, >>> + .attr = { .name = "bpf_testmod", .mode = 0666, }, >>> .read = bpf_testmod_test_read, >>> + .write = bpf_testmod_test_write, >>> }; >>> static int bpf_testmod_init(void) >>> diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.h b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.h >>> index b81adfedb4f6..b3892dc40111 100644 >>> --- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.h >>> +++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.h >>> @@ -11,4 +11,10 @@ struct bpf_testmod_test_read_ctx { >>> size_t len; >>> }; >>> +struct bpf_testmod_test_write_ctx { >>> + char *buf; >>> + loff_t off; >>> + size_t len; >>> +}; >>> + >>> #endif /* _BPF_TESTMOD_H */ >>> diff --git a/tools/testing/selftests/bpf/prog_tests/module_attach.c b/tools/testing/selftests/bpf/prog_tests/module_attach.c >>> index 50796b651f72..e4605c0b5af1 100644 >>> --- a/tools/testing/selftests/bpf/prog_tests/module_attach.c >>> +++ b/tools/testing/selftests/bpf/prog_tests/module_attach.c >>> @@ -21,9 +21,34 @@ static int trigger_module_test_read(int read_sz) >>> return 0; >>> } >>> +static int trigger_module_test_write(int write_sz) >>> +{ >>> + int fd, err; >> >> Init err = 0? > > I don't see what difference this makes. > >> >>> + char *buf = malloc(write_sz); >>> + >>> + if (!buf) >>> + return -ENOMEM; >> >> Looks like we already non-negative value, so return ENOMEM? > > We already set err=-errno. So shouldn't we return negative too? Oh, yes, return -ENOMEM sounds right here. > >> >>> + >>> + memset(buf, 'a', write_sz); >>> + buf[write_sz-1] = '\0'; >>> + >>> + fd = open("/sys/kernel/bpf_testmod", O_WRONLY); >>> + err = -errno; >>> + if (CHECK(fd < 0, "testmod_file_open", "failed: %d\n", err)) >>> + goto out; >> >> Change the above to >> fd = open("/sys/kernel/bpf_testmod", O_WRONLY); >> if (CHECK(fd < 0, "testmod_file_open", "failed: %d\n", errno)) { Here it should be ... "failed: %d\n", -errno. >> err = -errno; >> goto out; >> } > > I kept the code consistent with the definition of trigger_module_test_read(). The original patch code: +static int trigger_module_test_write(int write_sz) +{ + int fd, err; + char *buf = malloc(write_sz); + + if (!buf) + return -ENOMEM; + + memset(buf, 'a', write_sz); + buf[write_sz-1] = '\0'; + + fd = open("/sys/kernel/bpf_testmod", O_WRONLY); + err = -errno; + if (CHECK(fd < 0, "testmod_file_open", "failed: %d\n", err)) + goto out; + + write(fd, buf, write_sz); + close(fd); +out: + free(buf); + + return 0; +} Even for "fd < 0" case, it "goto out" and "return 0". We should return error code here instead of 0. Second, "err = -errno" is set before checking fd < 0. If fd >= 0, err might inherit an postive errno from previous failure. In trigger_module_test_write(), it is okay since the err is only used when fd < 0: err = -errno; if (CHECK(fd < 0, "testmod_file_open", "failed: %d\n", err)) return err; My above rewrite intends to use "err" during final "return" statement, so I put assignment of "err = -errno" inside the CHECK branch. But there are different ways to implement this properly. > > I'll leave it up to the maintainer to pick up the style changes if they prefer > it this way. > > Thanks for the ack and for the review. No problem. > > Cheers > > -- > Qais Yousef >
Hi Yonghong On 01/18/21 09:48, Yonghong Song wrote: > The original patch code: > > +static int trigger_module_test_write(int write_sz) > +{ > + int fd, err; > + char *buf = malloc(write_sz); > + > + if (!buf) > + return -ENOMEM; > + > + memset(buf, 'a', write_sz); > + buf[write_sz-1] = '\0'; > + > + fd = open("/sys/kernel/bpf_testmod", O_WRONLY); > + err = -errno; > + if (CHECK(fd < 0, "testmod_file_open", "failed: %d\n", err)) > + goto out; > + > + write(fd, buf, write_sz); > + close(fd); > +out: > + free(buf); > + > + return 0; > +} > > Even for "fd < 0" case, it "goto out" and "return 0". We should return > error code here instead of 0. > > Second, "err = -errno" is set before checking fd < 0. If fd >= 0, err might > inherit an postive errno from previous failure. > In trigger_module_test_write(), it is okay since the err is only used > when fd < 0: > err = -errno; > if (CHECK(fd < 0, "testmod_file_open", "failed: %d\n", err)) > return err; > > My above rewrite intends to use "err" during final "return" statement, > so I put assignment of "err = -errno" inside the CHECK branch. > But there are different ways to implement this properly. Okay I see now. Sorry I missed your point initially. I will fix and send v3. Thanks -- Qais Yousef
diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod-events.h b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod-events.h index b83ea448bc79..89c6d58e5dd6 100644 --- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod-events.h +++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod-events.h @@ -28,6 +28,12 @@ TRACE_EVENT(bpf_testmod_test_read, __entry->pid, __entry->comm, __entry->off, __entry->len) ); +/* A bare tracepoint with no event associated with it */ +DECLARE_TRACE(bpf_testmod_test_write_bare, + TP_PROTO(struct task_struct *task, struct bpf_testmod_test_write_ctx *ctx), + TP_ARGS(task, ctx) +); + #endif /* _BPF_TESTMOD_EVENTS_H */ #undef TRACE_INCLUDE_PATH diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c index 2df19d73ca49..e900adad2276 100644 --- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c +++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.c @@ -28,9 +28,28 @@ bpf_testmod_test_read(struct file *file, struct kobject *kobj, EXPORT_SYMBOL(bpf_testmod_test_read); ALLOW_ERROR_INJECTION(bpf_testmod_test_read, ERRNO); +noinline ssize_t +bpf_testmod_test_write(struct file *file, struct kobject *kobj, + struct bin_attribute *bin_attr, + char *buf, loff_t off, size_t len) +{ + struct bpf_testmod_test_write_ctx ctx = { + .buf = buf, + .off = off, + .len = len, + }; + + trace_bpf_testmod_test_write_bare(current, &ctx); + + return -EIO; /* always fail */ +} +EXPORT_SYMBOL(bpf_testmod_test_write); +ALLOW_ERROR_INJECTION(bpf_testmod_test_write, ERRNO); + static struct bin_attribute bin_attr_bpf_testmod_file __ro_after_init = { - .attr = { .name = "bpf_testmod", .mode = 0444, }, + .attr = { .name = "bpf_testmod", .mode = 0666, }, .read = bpf_testmod_test_read, + .write = bpf_testmod_test_write, }; static int bpf_testmod_init(void) diff --git a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.h b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.h index b81adfedb4f6..b3892dc40111 100644 --- a/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.h +++ b/tools/testing/selftests/bpf/bpf_testmod/bpf_testmod.h @@ -11,4 +11,10 @@ struct bpf_testmod_test_read_ctx { size_t len; }; +struct bpf_testmod_test_write_ctx { + char *buf; + loff_t off; + size_t len; +}; + #endif /* _BPF_TESTMOD_H */ diff --git a/tools/testing/selftests/bpf/prog_tests/module_attach.c b/tools/testing/selftests/bpf/prog_tests/module_attach.c index 50796b651f72..e4605c0b5af1 100644 --- a/tools/testing/selftests/bpf/prog_tests/module_attach.c +++ b/tools/testing/selftests/bpf/prog_tests/module_attach.c @@ -21,9 +21,34 @@ static int trigger_module_test_read(int read_sz) return 0; } +static int trigger_module_test_write(int write_sz) +{ + int fd, err; + char *buf = malloc(write_sz); + + if (!buf) + return -ENOMEM; + + memset(buf, 'a', write_sz); + buf[write_sz-1] = '\0'; + + fd = open("/sys/kernel/bpf_testmod", O_WRONLY); + err = -errno; + if (CHECK(fd < 0, "testmod_file_open", "failed: %d\n", err)) + goto out; + + write(fd, buf, write_sz); + close(fd); +out: + free(buf); + + return 0; +} + void test_module_attach(void) { const int READ_SZ = 456; + const int WRITE_SZ = 457; struct test_module_attach* skel; struct test_module_attach__bss *bss; int err; @@ -48,8 +73,10 @@ void test_module_attach(void) /* trigger tracepoint */ ASSERT_OK(trigger_module_test_read(READ_SZ), "trigger_read"); + ASSERT_OK(trigger_module_test_write(WRITE_SZ), "trigger_write"); ASSERT_EQ(bss->raw_tp_read_sz, READ_SZ, "raw_tp"); + ASSERT_EQ(bss->raw_tp_bare_write_sz, WRITE_SZ, "raw_tp_bare"); ASSERT_EQ(bss->tp_btf_read_sz, READ_SZ, "tp_btf"); ASSERT_EQ(bss->fentry_read_sz, READ_SZ, "fentry"); ASSERT_EQ(bss->fentry_manual_read_sz, READ_SZ, "fentry_manual"); diff --git a/tools/testing/selftests/bpf/progs/test_module_attach.c b/tools/testing/selftests/bpf/progs/test_module_attach.c index efd1e287ac17..bd37ceec5587 100644 --- a/tools/testing/selftests/bpf/progs/test_module_attach.c +++ b/tools/testing/selftests/bpf/progs/test_module_attach.c @@ -17,6 +17,16 @@ int BPF_PROG(handle_raw_tp, return 0; } +__u32 raw_tp_bare_write_sz = 0; + +SEC("raw_tp/bpf_testmod_test_write_bare") +int BPF_PROG(handle_raw_tp_bare, + struct task_struct *task, struct bpf_testmod_test_write_ctx *write_ctx) +{ + raw_tp_bare_write_sz = BPF_CORE_READ(write_ctx, len); + return 0; +} + __u32 tp_btf_read_sz = 0; SEC("tp_btf/bpf_testmod_test_read")
Reuse module_attach infrastructure to add a new bare tracepoint to check we can attach to it as a raw tracepoint. Signed-off-by: Qais Yousef <qais.yousef@arm.com> --- .../bpf/bpf_testmod/bpf_testmod-events.h | 6 +++++ .../selftests/bpf/bpf_testmod/bpf_testmod.c | 21 ++++++++++++++- .../selftests/bpf/bpf_testmod/bpf_testmod.h | 6 +++++ .../selftests/bpf/prog_tests/module_attach.c | 27 +++++++++++++++++++ .../selftests/bpf/progs/test_module_attach.c | 10 +++++++ 5 files changed, 69 insertions(+), 1 deletion(-)