From patchwork Sat May 4 00:30:05 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrii Nakryiko X-Patchwork-Id: 13653685 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 619EE1DDF4; Sat, 4 May 2024 00:30:21 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714782621; cv=none; b=Py2DDxc/4crp+LjGr5l3GD6Zvqen1RAwtdS4VEbAGL0AyBa4kLLsy/maZz6vccdwu5venoXm3mV7+bW1O7m+ZI/q3KYh2TBay2dmlknZlFGengHp9fmF180Q1vyQeFhegTOfUezNanbEM2J8pCcdXzqxChMs92ln1ItGMIR8s3M= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714782621; c=relaxed/simple; bh=YxeS+sLpQRnaSgu/9E3ClWUqEPF8Db9NHuIyW1Jsti8=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=C2yud+DDaPi3a9pcaeIOSAfyVGJQryQZm50Dj/ROrUbKMGED8yCBiBrCL6f2TDvxxKFslxZnfkTFK3M/UqIv/rzHrjVCs3QNkDVOp37NIpZT3CTi4Mp1FyAhJ7Mdv6/HhytONNkiAQhlLKCYAqsbb/fktiLoidT9Jpzi4sEN14M= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=KEgnPpHB; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="KEgnPpHB" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 08AAFC32789; Sat, 4 May 2024 00:30:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1714782621; bh=YxeS+sLpQRnaSgu/9E3ClWUqEPF8Db9NHuIyW1Jsti8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=KEgnPpHBAUag30KLKXRbcwwv5eSBfqoQqRe1IJe1bSxSom7XCLuXPyPJlx+VCp2A7 FRJ9upZx8QAsxZqb0ywEIr12qdiefeoYMQgEcQE3sFCkVzlo4BwwLTfVTS17gQ8pXS MJSfEPbXXyRUsJXYDTuy39AISOPZoOmP6UH+97Msw1OdtCErksIrOyWu9A8bOBR8DN gP20QGIvODzLTCLXHQhPR11wcdaZ5z/5ThA6YuXsRqoaLQMyy2i5LQBWwstFu91JBd 1cd08eKVWgqk1Iwc1kfGCnC7+S49U5eFUZNjZekrVZn2eM9uxF5rk8IdO/qkuaaxga x3SBOYcifgczw== From: Andrii Nakryiko To: linux-fsdevel@vger.kernel.org, brauner@kernel.org, viro@zeniv.linux.org.uk, akpm@linux-foundation.org Cc: linux-kernel@vger.kernel.org, bpf@vger.kernel.org, gregkh@linuxfoundation.org, linux-mm@kvack.org, Andrii Nakryiko Subject: [PATCH 4/5] selftests/bpf: make use of PROCFS_PROCMAP_QUERY ioctl, if available Date: Fri, 3 May 2024 17:30:05 -0700 Message-ID: <20240504003006.3303334-5-andrii@kernel.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240504003006.3303334-1-andrii@kernel.org> References: <20240504003006.3303334-1-andrii@kernel.org> Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Instead of parsing text-based /proc//maps file, try to use PROCFS_PROCMAP_QUERY ioctl() to simplify and speed up data fetching. This logic is used to do uprobe file offset calculation, so any bugs in this logic would manifest as failing uprobe BPF selftests. This also serves as a simple demonstration of one of the intended uses. Signed-off-by: Andrii Nakryiko --- tools/testing/selftests/bpf/test_progs.c | 3 + tools/testing/selftests/bpf/test_progs.h | 2 + tools/testing/selftests/bpf/trace_helpers.c | 105 +++++++++++++++++--- 3 files changed, 95 insertions(+), 15 deletions(-) diff --git a/tools/testing/selftests/bpf/test_progs.c b/tools/testing/selftests/bpf/test_progs.c index 89ff704e9dad..6a19970f2531 100644 --- a/tools/testing/selftests/bpf/test_progs.c +++ b/tools/testing/selftests/bpf/test_progs.c @@ -19,6 +19,8 @@ #include #include "json_writer.h" +int env_verbosity = 0; + static bool verbose(void) { return env.verbosity > VERBOSE_NONE; @@ -848,6 +850,7 @@ static error_t parse_arg(int key, char *arg, struct argp_state *state) return -EINVAL; } } + env_verbosity = env->verbosity; if (verbose()) { if (setenv("SELFTESTS_VERBOSE", "1", 1) == -1) { diff --git a/tools/testing/selftests/bpf/test_progs.h b/tools/testing/selftests/bpf/test_progs.h index 0ba5a20b19ba..6eae7fdab0d7 100644 --- a/tools/testing/selftests/bpf/test_progs.h +++ b/tools/testing/selftests/bpf/test_progs.h @@ -95,6 +95,8 @@ struct test_state { FILE *stdout; }; +extern int env_verbosity; + struct test_env { struct test_selector test_selector; struct test_selector subtest_selector; diff --git a/tools/testing/selftests/bpf/trace_helpers.c b/tools/testing/selftests/bpf/trace_helpers.c index 70e29f316fe7..8ac71e73d173 100644 --- a/tools/testing/selftests/bpf/trace_helpers.c +++ b/tools/testing/selftests/bpf/trace_helpers.c @@ -10,6 +10,8 @@ #include #include #include +#include +#include #include #include "trace_helpers.h" #include @@ -233,29 +235,92 @@ int kallsyms_find(const char *sym, unsigned long long *addr) return err; } +#ifdef PROCFS_PROCMAP_QUERY +int env_verbosity __weak = 0; + +int procmap_query(int fd, const void *addr, size_t *start, size_t *offset, int *flags) +{ + char path_buf[PATH_MAX], build_id_buf[20]; + struct procfs_procmap_query q; + int err; + + memset(&q, 0, sizeof(q)); + q.size = sizeof(q); + q.query_addr = (__u64)addr; + q.vma_name_addr = (__u64)path_buf; + q.vma_name_size = sizeof(path_buf); + q.build_id_addr = (__u64)build_id_buf; + q.build_id_size = sizeof(build_id_buf); + + err = ioctl(fd, PROCFS_PROCMAP_QUERY, &q); + if (err < 0) { + err = -errno; + if (err == -ENOTTY) + return -EOPNOTSUPP; /* ioctl() not implemented yet */ + if (err == -ENOENT) + return -ESRCH; /* vma not found */ + return err; + } + + if (env_verbosity >= 1) { + printf("VMA FOUND (addr %08lx): %08lx-%08lx %c%c%c%c %08lx %02x:%02x %ld %s (build ID: %s, %d bytes)\n", + (long)addr, (long)q.vma_start, (long)q.vma_end, + (q.vma_flags & PROCFS_PROCMAP_VMA_READABLE) ? 'r' : '-', + (q.vma_flags & PROCFS_PROCMAP_VMA_WRITABLE) ? 'w' : '-', + (q.vma_flags & PROCFS_PROCMAP_VMA_EXECUTABLE) ? 'x' : '-', + (q.vma_flags & PROCFS_PROCMAP_VMA_SHARED) ? 's' : 'p', + (long)q.vma_offset, q.dev_major, q.dev_minor, (long)q.inode, + q.vma_name_size ? path_buf : "", + q.build_id_size ? "YES" : "NO", + q.build_id_size); + } + + *start = q.vma_start; + *offset = q.vma_offset; + *flags = q.vma_flags; + return 0; +} +#else +int procmap_query(int fd, const void *addr, size_t *start, size_t *offset, int *flags) +{ + return -EOPNOTSUPP; +} +#endif + ssize_t get_uprobe_offset(const void *addr) { - size_t start, end, base; - char buf[256]; - bool found = false; + size_t start, base, end; FILE *f; + char buf[256]; + int err, flags; f = fopen("/proc/self/maps", "r"); if (!f) return -errno; - while (fscanf(f, "%zx-%zx %s %zx %*[^\n]\n", &start, &end, buf, &base) == 4) { - if (buf[2] == 'x' && (uintptr_t)addr >= start && (uintptr_t)addr < end) { - found = true; - break; + err = procmap_query(fileno(f), addr, &start, &base, &flags); + if (err == 0) { + if (!(flags & PROCFS_PROCMAP_VMA_EXECUTABLE)) + return -ESRCH; + } else if (err != -EOPNOTSUPP) { + fclose(f); + return err; + } else if (err) { + bool found = false; + + while (fscanf(f, "%zx-%zx %s %zx %*[^\n]\n", &start, &end, buf, &base) == 4) { + if (buf[2] == 'x' && (uintptr_t)addr >= start && (uintptr_t)addr < end) { + found = true; + break; + } + } + if (!found) { + fclose(f); + return -ESRCH; } } - fclose(f); - if (!found) - return -ESRCH; - #if defined(__powerpc64__) && defined(_CALL_ELF) && _CALL_ELF == 2 #define OP_RT_RA_MASK 0xffff0000UL @@ -296,15 +361,25 @@ ssize_t get_rel_offset(uintptr_t addr) size_t start, end, offset; char buf[256]; FILE *f; + int err, flags; f = fopen("/proc/self/maps", "r"); if (!f) return -errno; - while (fscanf(f, "%zx-%zx %s %zx %*[^\n]\n", &start, &end, buf, &offset) == 4) { - if (addr >= start && addr < end) { - fclose(f); - return (size_t)addr - start + offset; + err = procmap_query(fileno(f), (const void *)addr, &start, &offset, &flags); + if (err == 0) { + fclose(f); + return (size_t)addr - start + offset; + } else if (err != -EOPNOTSUPP) { + fclose(f); + return err; + } else if (err) { + while (fscanf(f, "%zx-%zx %s %zx %*[^\n]\n", &start, &end, buf, &offset) == 4) { + if (addr >= start && addr < end) { + fclose(f); + return (size_t)addr - start + offset; + } } }