| Message ID | 1447675815-166222-13-git-send-email-wangnan0@huawei.com |
|---|---|
| State | New |
| Headers | show |
On 2015/11/17 9:29, Arnaldo Carvalho de Melo wrote: > Em Mon, Nov 16, 2015 at 12:10:14PM +0000, Wang Nan escreveu: >> This patch introduces a new BPF script to test BPF prologue. The new >> script probes at null_lseek, which is the function pointer when we try >> to lseek on '/dev/null'. >> >> null_lseek is chosen because it is a function pointer, so we don't need >> to consider inlining and LTO. >> >> By extracting file->f_mode, bpf-script-test-prologue.c should know whether >> the file is writable or readonly. According to llseek_loop() and >> bpf-script-test-prologue.c, one forth of total lseeks should be collected. > So I tentatively changed the section name key=val separator from '\n' to > ';', applied all the patches up to this one (will review the last one > tomorrow), and tested it, reproducing your results, for some reason that > SEC() wasn't working, have to check again, using it expanded, as in my > previous tests, works, I updated the comments to reflect the tests I > did, please take a look. > > I've pushed everything to my perf/ebpf branch, please let me know if > what is there is acceptable, then it will be up to Ingo to decide where > to put this, if in perf/urgent for this merge window, or in perf/core, > for the next one. > > Ah, to extract the output for these BPF sub-tests I had to use -v, i.e. > just: > > # perf test BPF > 37: Test BPF filter : Ok > # > > Ditto for the LLVM one. > > Doesn't tell us too much about all those nice sub-tests... > > How about: > > # perf test -v BPF > 37: Test BPF filter: > 37.1: test a : Ok > 37.2: test b : Ok > 37.3: Test BPF prologue generation : Ok > 37.4: Another... : Ok > 37: Test BPF filter : Ok > # > > Thanks! Thanks to your work. I'm checking them now. > - Arnaldo > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
On 2015/11/17 9:29, Arnaldo Carvalho de Melo wrote: > Em Mon, Nov 16, 2015 at 12:10:14PM +0000, Wang Nan escreveu: >> This patch introduces a new BPF script to test BPF prologue. The new >> script probes at null_lseek, which is the function pointer when we try >> to lseek on '/dev/null'. >> >> null_lseek is chosen because it is a function pointer, so we don't need >> to consider inlining and LTO. >> >> By extracting file->f_mode, bpf-script-test-prologue.c should know whether >> the file is writable or readonly. According to llseek_loop() and >> bpf-script-test-prologue.c, one forth of total lseeks should be collected. > So I tentatively changed the section name key=val separator from '\n' to > ';', applied all the patches up to this one (will review the last one > tomorrow), and tested it, reproducing your results, for some reason that > SEC() wasn't working, have to check again, using it expanded, as in my > previous tests, works, I updated the comments to reflect the tests I > did, please take a look. > > I've pushed everything to my perf/ebpf branch, please let me know if > what is there is acceptable, then it will be up to Ingo to decide where > to put this, if in perf/urgent for this merge window, or in perf/core, > for the next one. > > Ah, to extract the output for these BPF sub-tests I had to use -v, i.e. > just: > > # perf test BPF > 37: Test BPF filter : Ok > # > > Ditto for the LLVM one. > > Doesn't tell us too much about all those nice sub-tests... > > How about: > > # perf test -v BPF > 37: Test BPF filter: > 37.1: test a : Ok > 37.2: test b : Ok > 37.3: Test BPF prologue generation : Ok > 37.4: Another... : Ok > 37: Test BPF filter : Ok > # > > Thanks! I think what you want is to report state of subtests *without* -v? That would be nice but changing of perf testing infrastructure is required because there's no "sub-test" before, and we both agree that testcase should be silent without '-v', so we need a way to output them in builtin-test.c. Let me try it but I think it should not be a blocking problem. Thank you. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Hi Arnaldo, On 2015/11/17 9:29, Arnaldo Carvalho de Melo wrote: [SNIP] > I've pushed everything to my perf/ebpf branch, please let me know if > what is there is acceptable, then it will be up to Ingo to decide where > to put this, if in perf/urgent for this merge window, or in perf/core, > for the next one. I have checked and tested your changes in your perf/ebpf and they are okay to me. > > Ah, to extract the output for these BPF sub-tests I had to use -v, i.e. > just: > > # perf test BPF > 37: Test BPF filter : Ok > # > > Ditto for the LLVM one. > > Doesn't tell us too much about all those nice sub-tests... > > How about: > > # perf test -v BPF > 37: Test BPF filter: > 37.1: test a : Ok > 37.2: test b : Ok > 37.3: Test BPF prologue generation : Ok > 37.4: Another... : Ok > 37: Test BPF filter : Ok > # I have sent a cset based on perf/ebpf in [1]. With the last 3 patch you will see 'perf test' output information in this way. Please have a try: # ./perf test LLVM BPF 35: Test LLVM searching and compiling : 35.1: Basic BPF llvm compiling test : Ok 35.2: Test kbuild searching : Ok 35.3: Compile source for BPF prologue generation test : Ok 37: Test BPF filter : 37.1: Test basic BPF filtering : Ok 37.2: Test BPF prologue generation : Ok Thank you. [1] http://lkml.kernel.org/g/1447749170-175898-1-git-send-email-wangnan0@huawei.com -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
diff --git a/tools/perf/tests/Build b/tools/perf/tests/Build index f41ebf8..0ff8a97 100644 --- a/tools/perf/tests/Build +++ b/tools/perf/tests/Build @@ -31,7 +31,7 @@ perf-y += sample-parsing.o perf-y += parse-no-sample-id-all.o perf-y += kmod-path.o perf-y += thread-map.o -perf-y += llvm.o llvm-src-base.o llvm-src-kbuild.o +perf-y += llvm.o llvm-src-base.o llvm-src-kbuild.o llvm-src-prologue.o perf-y += bpf.o perf-y += topology.o @@ -49,6 +49,13 @@ $(OUTPUT)tests/llvm-src-kbuild.c: tests/bpf-script-test-kbuild.c $(Q)sed -e 's/"/\\"/g' -e 's/\(.*\)/"\1\\n"/g' $< >> $@ $(Q)echo ';' >> $@ +$(OUTPUT)tests/llvm-src-prologue.c: tests/bpf-script-test-prologue.c + $(call rule_mkdir) + $(Q)echo '#include <tests/llvm.h>' > $@ + $(Q)echo 'const char test_llvm__bpf_test_prologue_prog[] =' >> $@ + $(Q)sed -e 's/"/\\"/g' -e 's/\(.*\)/"\1\\n"/g' $< >> $@ + $(Q)echo ';' >> $@ + ifeq ($(ARCH),$(filter $(ARCH),x86 arm arm64)) perf-$(CONFIG_DWARF_UNWIND) += dwarf-unwind.o endif diff --git a/tools/perf/tests/bpf-script-test-prologue.c b/tools/perf/tests/bpf-script-test-prologue.c new file mode 100644 index 0000000..7230e62 --- /dev/null +++ b/tools/perf/tests/bpf-script-test-prologue.c @@ -0,0 +1,35 @@ +/* + * bpf-script-test-prologue.c + * Test BPF prologue + */ +#ifndef LINUX_VERSION_CODE +# error Need LINUX_VERSION_CODE +# error Example: for 4.2 kernel, put 'clang-opt="-DLINUX_VERSION_CODE=0x40200" into llvm section of ~/.perfconfig' +#endif +#define SEC(NAME) __attribute__((section(NAME), used)) + +#include <uapi/linux/fs.h> + +#define FMODE_READ 0x1 +#define FMODE_WRITE 0x2 + +static void (*bpf_trace_printk)(const char *fmt, int fmt_size, ...) = + (void *) 6; + +SEC("func=null_lseek file->f_mode offset orig") +int bpf_func__null_lseek(void *ctx, int err, unsigned long f_mode, + unsigned long offset, unsigned long orig) +{ + if (err) + return 0; + if (f_mode & FMODE_WRITE) + return 0; + if (offset & 1) + return 0; + if (orig == SEEK_CUR) + return 0; + return 1; +} + +char _license[] SEC("license") = "GPL"; +int _version SEC("version") = LINUX_VERSION_CODE; diff --git a/tools/perf/tests/bpf.c b/tools/perf/tests/bpf.c index ec16f78..c7131fa 100644 --- a/tools/perf/tests/bpf.c +++ b/tools/perf/tests/bpf.c @@ -19,6 +19,29 @@ static int epoll_pwait_loop(void) return 0; } +#ifdef HAVE_BPF_PROLOGUE + +static int llseek_loop(void) +{ + int fds[2], i; + + fds[0] = open("/dev/null", O_RDONLY); + fds[1] = open("/dev/null", O_RDWR); + + if (fds[0] < 0 || fds[1] < 0) + return -1; + + for (i = 0; i < NR_ITERS; i++) { + lseek(fds[i % 2], i, (i / 2) % 2 ? SEEK_CUR : SEEK_SET); + lseek(fds[(i + 1) % 2], i, (i / 2) % 2 ? SEEK_CUR : SEEK_SET); + } + close(fds[0]); + close(fds[1]); + return 0; +} + +#endif + static struct { enum test_llvm__testcase prog_id; const char *desc; @@ -37,6 +60,17 @@ static struct { &epoll_pwait_loop, (NR_ITERS + 1) / 2, }, +#ifdef HAVE_BPF_PROLOGUE + { + LLVM_TESTCASE_BPF_PROLOGUE, + "Test BPF prologue generation", + "[bpf_prologue_test]", + "fix kbuild first", + "check your vmlinux setting?", + &llseek_loop, + (NR_ITERS + 1) / 4, + }, +#endif }; static int do_test(struct bpf_object *obj, int (*func)(void), diff --git a/tools/perf/tests/llvm.c b/tools/perf/tests/llvm.c index bc4cf50..7f4f7f7 100644 --- a/tools/perf/tests/llvm.c +++ b/tools/perf/tests/llvm.c @@ -44,6 +44,10 @@ static struct { .source = test_llvm__bpf_test_kbuild_prog, .desc = "Test kbuild searching", }, + [LLVM_TESTCASE_BPF_PROLOGUE] = { + .source = test_llvm__bpf_test_prologue_prog, + .desc = "Test BPF prologue generation", + }, }; diff --git a/tools/perf/tests/llvm.h b/tools/perf/tests/llvm.h index d91d8f4..5150b4d 100644 --- a/tools/perf/tests/llvm.h +++ b/tools/perf/tests/llvm.h @@ -6,10 +6,12 @@ extern const char test_llvm__bpf_base_prog[]; extern const char test_llvm__bpf_test_kbuild_prog[]; +extern const char test_llvm__bpf_test_prologue_prog[]; enum test_llvm__testcase { LLVM_TESTCASE_BASE, LLVM_TESTCASE_KBUILD, + LLVM_TESTCASE_BPF_PROLOGUE, __LLVM_TESTCASE_MAX, };
This patch introduces a new BPF script to test BPF prologue. The new script probes at null_lseek, which is the function pointer when we try to lseek on '/dev/null'. null_lseek is chosen because it is a function pointer, so we don't need to consider inlining and LTO. By extracting file->f_mode, bpf-script-test-prologue.c should know whether the file is writable or readonly. According to llseek_loop() and bpf-script-test-prologue.c, one forth of total lseeks should be collected. Signed-off-by: Wang Nan <wangnan0@huawei.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> Cc: Zefan Li <lizefan@huawei.com> Cc: pi3orama@163.com --- tools/perf/tests/Build | 9 +++++++- tools/perf/tests/bpf-script-test-prologue.c | 35 +++++++++++++++++++++++++++++ tools/perf/tests/bpf.c | 34 ++++++++++++++++++++++++++++ tools/perf/tests/llvm.c | 4 ++++ tools/perf/tests/llvm.h | 2 ++ 5 files changed, 83 insertions(+), 1 deletion(-) create mode 100644 tools/perf/tests/bpf-script-test-prologue.c -- 1.8.3.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/