arch: use gperf to generate a perfact hash to lookup syscall names

This patch significantly improves the performance of
seccomp_syscall_resolve_name since it replaces the expensive strcmp
for each syscall in the database, with a lookup table.

The complexity for syscall_resolve_num is not changed and it
uses the linear search, that is anyway less expensive than
seccomp_syscall_resolve_name as it uses an index for comparison
instead of doing a string comparison.

On my machine, calling 1000 seccomp_syscall_resolve_name_arch and
seccomp_syscall_resolve_num_arch over the entire syscalls DB passed
from ~0.45 sec to ~0.06s.

PM: After talking with Giuseppe I made a number of additional
changes, some substantial, the highlights include:
* various style tweaks
* .gitignore fixes
* fixed subject line, tweaked the description
* dropped the arch-syscall-validate changes as they were masking
  other problems
* extracted the syscalls.csv and file deletions to other patches
  to keep this one more focused
* fixed the x86, x32, arm, all the MIPS ABIs, s390, and s390x ABIs as
  the syscall offsets were not properly incorporated into this change
* cleaned up the ABI specific headers
* cleaned up generate_syscalls_perf.sh and renamed to
  arch-gperf-generate
* fixed problems with automake's file packaging

Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
Reviewed-by: Tom Hromatka <tom.hromatka@oracle.com>
[PM: see notes in the "PM" section above]
Signed-off-by: Paul Moore <paul@paul-moore.com>

5 files changed, 173 insertions, 3 deletions

diff --git a/tests/.gitignore b/tests/.gitignore
index bd00e14..c536766 100644
--- a/tests/.gitignore
+++ b/tests/.gitignore
@@ -61,3 +61,4 @@ util.pyc
 53-sim-binary_tree
 54-live-binary_tree
 55-basic-pfc_binary_tree
+56-basic-iterate_syscalls
diff --git a/tests/56-basic-iterate_syscalls.c b/tests/56-basic-iterate_syscalls.c
new file mode 100644
index 0000000..5e7ab67
--- /dev/null
+++ b/tests/56-basic-iterate_syscalls.c
@@ -0,0 +1,90 @@
+/**
+ * Seccomp Library test program
+ *
+ * Copyright (c) 2020 Red Hat <gscrivan@redhat.com>
+ * Author: Giuseppe Scrivano <gscrivan@redhat.com>
+ */
+
+/*
+ * This library is free software; you can redistribute it and/or modify it
+ * under the terms of version 2.1 of the GNU Lesser General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This library is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this library; if not, see <http://www.gnu.org/licenses>.
+ */
+
+#include <errno.h>
+#include <string.h>
+#include <stdlib.h>
+#include <stdio.h>
+
+#include <seccomp.h>
+
+unsigned int arch_list[] = {
+	SCMP_ARCH_NATIVE,
+	SCMP_ARCH_X86,
+	SCMP_ARCH_X86_64,
+	SCMP_ARCH_X32,
+	SCMP_ARCH_ARM,
+	SCMP_ARCH_AARCH64,
+	SCMP_ARCH_MIPS,
+	SCMP_ARCH_MIPS64,
+	SCMP_ARCH_MIPS64N32,
+	SCMP_ARCH_MIPSEL,
+	SCMP_ARCH_MIPSEL64,
+	SCMP_ARCH_MIPSEL64N32,
+	SCMP_ARCH_PPC,
+	SCMP_ARCH_PPC64,
+	SCMP_ARCH_PPC64LE,
+	SCMP_ARCH_S390,
+	SCMP_ARCH_S390X,
+	SCMP_ARCH_PARISC,
+	SCMP_ARCH_PARISC64,
+	SCMP_ARCH_RISCV64,
+	-1
+};
+
+static int test_arch(int arch, int init)
+{
+	int n, iter = 0;
+
+	for (iter = init; iter < init + 1000; iter++) {
+		char *name;
+
+		name = seccomp_syscall_resolve_num_arch(arch, iter);
+		if (name == NULL)
+			continue;
+
+		n = seccomp_syscall_resolve_name_arch(arch, name);
+		if (n != iter)
+			return 1;
+	}
+	return 0;
+}
+
+int main(int argc, char *argv[])
+{
+	int iter = 0;
+
+	for (iter = 0; arch_list[iter] != -1; iter++) {
+		int init = 0;
+		if (arch_list[iter] == SCMP_ARCH_X32)
+			init = 0x40000000;
+		else if (arch_list[iter] == SCMP_ARCH_MIPS)
+			init = 4000;
+		else if (arch_list[iter] == SCMP_ARCH_MIPS64)
+			init = 5000;
+		else if (arch_list[iter] == SCMP_ARCH_MIPS64N32)
+			init = 6000;
+		if (test_arch(arch_list[iter], init) < 0)
+			return 1;
+	}
+
+	return 0;
+}
diff --git a/tests/56-basic-iterate_syscalls.py b/tests/56-basic-iterate_syscalls.py
new file mode 100755
index 0000000..77a5b89
--- /dev/null
+++ b/tests/56-basic-iterate_syscalls.py
@@ -0,0 +1,65 @@
+#!/usr/bin/env python
+
+#
+# Seccomp Library test program
+#
+# Copyright (c) 2020 Red Hat <gscrivan@redhat.com>
+# Author: Giuseppe Scrivano <gscrivan@redhat.com>
+#
+
+#
+# This library is free software; you can redistribute it and/or modify it
+# under the terms of version 2.1 of the GNU Lesser General Public License as
+# published by the Free Software Foundation.
+#
+# This library is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
+# for more details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with this library; if not, see <http://www.gnu.org/licenses>.
+#
+
+import argparse
+import sys
+
+import util
+
+from seccomp import *
+
+arch_list = ["x86",
+             "x86_64",
+             "x32",
+             "arm",
+             "aarch64",
+             "mipsel",
+             "mipsel64",
+             "mipsel64n32",
+             "ppc64le",
+             "riscv64"]
+
+def test_arch(arch, init):
+    for i in range(init, init + 1000):
+        sys_name = resolve_syscall(arch, i)
+        if sys_name is None:
+            continue
+        n = resolve_syscall(i, sys_name)
+        if i != n:
+            raise RuntimeError("Test failure")
+
+def test():
+    for i in arch_list:
+        init = 0
+        if i == "x32":
+            init = 0x40000000
+        elif i == "mipsel":
+            init = 4000
+        elif i == "mipsel64":
+            init = 5000
+        elif i == "mipsel64n32":
+            init = 6000
+        test_arch(Arch(i), init)
+
+# kate: syntax python;
+# kate: indent-mode python; space-indent on; indent-width 4; mixedindent off;
diff --git a/tests/56-basic-iterate_syscalls.tests b/tests/56-basic-iterate_syscalls.tests
new file mode 100644
index 0000000..a84415a
--- /dev/null
+++ b/tests/56-basic-iterate_syscalls.tests
@@ -0,0 +1,11 @@
+#
+# libseccomp regression test automation data
+#
+# Copyright (c) 2020 Red Hat <gscrivan@redhat.com>
+# Author: Giuseppe Scrivano <gscrivan@redhat.com>
+#
+
+test type: basic
+
+# Test command
+56-basic-iterate_syscalls
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 4bd19c8..a135278 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -94,7 +94,8 @@ check_PROGRAMS = \
 	52-basic-load \
 	53-sim-binary_tree \
 	54-live-binary_tree \
-	55-basic-pfc_binary_tree
+	55-basic-pfc_binary_tree \
+	56-basic-iterate_syscalls
 
 EXTRA_DIST_TESTPYTHON = \
 	util.py \
@@ -150,7 +151,8 @@ EXTRA_DIST_TESTPYTHON = \
 	51-live-user_notification.py \
 	52-basic-load.py \
 	53-sim-binary_tree.py \
-	54-live-binary_tree.py
+	54-live-binary_tree.py \
+	56-basic-iterate_syscalls.py
 
 EXTRA_DIST_TESTCFGS = \
 	01-sim-allow.tests \
@@ -207,7 +209,8 @@ EXTRA_DIST_TESTCFGS = \
 	52-basic-load.tests \
 	53-sim-binary_tree.tests \
 	54-live-binary_tree.tests \
-	55-basic-pfc_binary_tree.tests
+	55-basic-pfc_binary_tree.tests \
+	56-basic-iterate_syscalls.tests
 
 EXTRA_DIST_TESTSCRIPTS = \
 	38-basic-pfc_coverage.sh 38-basic-pfc_coverage.pfc \