From: Denis Mukhin <dmuk...@ford.com>
Introduce some basic infrastructure for doing domain ID allocation unit tests,
and add a few tests that ensure correctness of the domain ID allocator.
Use <xen-tools/bitops.h> and xen/lib/find-next-bit.c in test hardness code.
Adjust find-next-bit.c to be compiled with __XEN_TOOLS__.
Signed-off-by: Denis Mukhin <dmuk...@ford.com>
Reviewed-by: Julien Grall <jgr...@amazon.com>
---
Changes since v14:
- addressed NITs from v14's review
- extended the test for exact IDs allocation (trivial change)
- added Julien's R-b
---
tools/include/xen-tools/bitops.h | 10 +++
tools/tests/Makefile | 1 +
tools/tests/domid/.gitignore | 2 +
tools/tests/domid/Makefile | 56 ++++++++++++++++
tools/tests/domid/harness.h | 54 +++++++++++++++
tools/tests/domid/include/xen/domain.h | 1 +
tools/tests/domid/test-domid.c | 93 ++++++++++++++++++++++++++
xen/lib/find-next-bit.c | 5 ++
8 files changed, 222 insertions(+)
create mode 100644 tools/tests/domid/.gitignore
create mode 100644 tools/tests/domid/Makefile
create mode 100644 tools/tests/domid/harness.h
create mode 120000 tools/tests/domid/include/xen/domain.h
create mode 100644 tools/tests/domid/test-domid.c
diff --git a/tools/include/xen-tools/bitops.h b/tools/include/xen-tools/bitops.h
index 681482f6759f..3b98fba6d74c 100644
--- a/tools/include/xen-tools/bitops.h
+++ b/tools/include/xen-tools/bitops.h
@@ -12,6 +12,16 @@
#define BITS_PER_LONG 32
#endif
+#define ffsl(x) __builtin_ffsl(x)
+
+#define BIT_WORD(nr) ((nr) / BITS_PER_LONG)
+
+#define BITS_TO_LONGS(bits) \
+ (((bits) + BITS_PER_LONG - 1) / BITS_PER_LONG)
+
+#define DECLARE_BITMAP(name, bits) \
+ unsigned long name[BITS_TO_LONGS(bits)]
+
#define BITMAP_ENTRY(_nr,_bmap) ((_bmap))[(_nr) / 8]
#define BITMAP_SHIFT(_nr) ((_nr) % 8)
diff --git a/tools/tests/Makefile b/tools/tests/Makefile
index 36928676a666..94fa80c16880 100644
--- a/tools/tests/Makefile
+++ b/tools/tests/Makefile
@@ -2,6 +2,7 @@ XEN_ROOT = $(CURDIR)/../..
include $(XEN_ROOT)/tools/Rules.mk
SUBDIRS-y :=
+SUBDIRS-y += domid
SUBDIRS-y += resource
SUBDIRS-$(CONFIG_X86) += cpu-policy
SUBDIRS-$(CONFIG_X86) += tsx
diff --git a/tools/tests/domid/.gitignore b/tools/tests/domid/.gitignore
new file mode 100644
index 000000000000..70e306b3c074
--- /dev/null
+++ b/tools/tests/domid/.gitignore
@@ -0,0 +1,2 @@
+*.o
+test-domid
diff --git a/tools/tests/domid/Makefile b/tools/tests/domid/Makefile
new file mode 100644
index 000000000000..d96ceca6d954
--- /dev/null
+++ b/tools/tests/domid/Makefile
@@ -0,0 +1,56 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Unit tests for domain ID allocator.
+#
+# Copyright 2025 Ford Motor Company
+
+XEN_ROOT=$(CURDIR)/../../..
+include $(XEN_ROOT)/tools/Rules.mk
+
+TESTS := test-domid
+
+vpath domid.c $(XEN_ROOT)/xen/common/
+vpath find-next-bit.c $(XEN_ROOT)/xen/lib/
+
+.PHONY: all
+all: $(TESTS)
+
+.PHONY: run
+run: $(TESTS)
+ $(foreach t,$(TESTS),./$(t);)
+
+.PHONY: clean
+clean:
+ $(RM) -- *.o $(TESTS) $(DEPS_RM)
+
+.PHONY: distclean
+distclean: clean
+ $(RM) -- *~
+
+.PHONY: install
+install: all
+ $(INSTALL_DIR) $(DESTDIR)$(LIBEXEC)/tests
+ $(INSTALL_PROG) test-domid $(DESTDIR)$(LIBEXEC)/tests
+
+.PHONY: uninstall
+uninstall:
+ $(RM) -- $(DESTDIR)$(LIBEXEC)/tests/test-domid
+
+CFLAGS += -D__XEN_TOOLS__
+# find-next-bit.c
+CFLAGS += '-DEXPORT_SYMBOL(x)=' \
+ -Dfind_first_bit \
+ -Dfind_first_zero_bit \
+ -Dfind_next_bit \
+ -Dfind_next_bit_le \
+ -Dfind_next_zero_bit_le
+CFLAGS += $(APPEND_CFLAGS)
+CFLAGS += $(CFLAGS_xeninclude)
+CFLAGS += -I./include/
+
+LDFLAGS += $(APPEND_LDFLAGS)
+
+test-domid: domid.o find-next-bit.o test-domid.o
+ $(CC) $^ -o $@ $(LDFLAGS)
+
+-include $(DEPS_INCLUDE)
diff --git a/tools/tests/domid/harness.h b/tools/tests/domid/harness.h
new file mode 100644
index 000000000000..17eb22a9a854
--- /dev/null
+++ b/tools/tests/domid/harness.h
@@ -0,0 +1,54 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Unit test harness for domain ID allocator.
+ *
+ * Copyright 2025 Ford Motor Company
+ */
+
+#ifndef _TEST_HARNESS_
+#define _TEST_HARNESS_
+
+#include <assert.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+
+#include <xen-tools/common-macros.h>
+#include <xen-tools/bitops.h>
+
+typedef bool spinlock_t;
+typedef uint16_t domid_t;
+
+extern domid_t domid_alloc(domid_t domid);
+extern void domid_free(domid_t domid);
+
+extern unsigned long find_next_zero_bit(const unsigned long *addr,
+ unsigned long size,
+ unsigned long offset);
+
+#define __test_and_set_bit(nr, addr) test_and_set_bit(nr, addr)
+#define __test_and_clear_bit(nr, addr) test_and_clear_bit(nr, addr)
+#define __set_bit(nr, addr) set_bit(nr, addr)
+
+#define BUG_ON(x) assert(!(x))
+#define ASSERT(x) assert(x)
+
+#define DEFINE_SPINLOCK(l) spinlock_t l
+#define spin_lock(l) (assert(!*(l)), *(l) = true)
+#define spin_unlock(l) (assert(*(l)), *(l) = false)
+
+#define printk printf
+
+#define DOMID_FIRST_RESERVED (100)
+#define DOMID_INVALID (101)
+
+#endif /* _TEST_HARNESS_ */
+
+/*
+ * Local variables:
+ * mode: C
+ * c-file-style: "BSD"
+ * c-basic-offset: 4
+ * indent-tabs-mode: nil
+ * End:
+ */
diff --git a/tools/tests/domid/include/xen/domain.h
b/tools/tests/domid/include/xen/domain.h
new file mode 120000
index 000000000000..2eda9aed088e
--- /dev/null
+++ b/tools/tests/domid/include/xen/domain.h
@@ -0,0 +1 @@
+../../harness.h
\ No newline at end of file
diff --git a/tools/tests/domid/test-domid.c b/tools/tests/domid/test-domid.c
new file mode 100644
index 000000000000..51a88a6a9550
--- /dev/null
+++ b/tools/tests/domid/test-domid.c
@@ -0,0 +1,93 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Unit tests for domain ID allocator.
+ *
+ * Copyright 2025 Ford Motor Company
+ */
+
+#include "harness.h"
+
+#define verify(exp, fmt, args...) do { \
+ if ( !(exp) ) \
+ printf(fmt, ## args); \
+ assert(exp); \
+} while (0);
+
+/*
+ * Fail on the first error, since tests are dependent on each other.
+ */
+int main(int argc, char **argv)
+{
+ domid_t expected, allocated;
+
+ /* Test ID cannot be allocated twice. */
+ for ( expected = 0; expected < DOMID_FIRST_RESERVED; expected++ )
+ {
+ allocated = domid_alloc(expected);
+ verify(allocated == expected,
+ "TEST 1: expected %u allocated %u\n", expected, allocated);
+ }
+ for ( expected = 0; expected < DOMID_FIRST_RESERVED; expected++ )
+ {
+ allocated = domid_alloc(expected);
+ verify(allocated == DOMID_INVALID,
+ "TEST 2: expected %u allocated %u\n", DOMID_INVALID, allocated);
+ }
+
+ /* Ensure all IDs, including ID#0 are not allocated. */
+ for ( expected = 0; expected < DOMID_FIRST_RESERVED; expected++ )
+ domid_free(expected);
+
+ /*
+ * Test that that two consecutive calls of domid_alloc(DOMID_INVALID)
+ * will never return the same ID.
+ * NB: ID#0 is reserved and shall not be allocated by
+ * domid_alloc(DOMID_INVALID).
+ */
+ for ( expected = 1; expected < DOMID_FIRST_RESERVED; expected++ )
+ {
+ allocated = domid_alloc(DOMID_INVALID);
+ verify(allocated == expected,
+ "TEST 3: expected %u allocated %u\n", expected, allocated);
+ }
+ for ( expected = 1; expected < DOMID_FIRST_RESERVED; expected++ )
+ {
+ allocated = domid_alloc(DOMID_INVALID);
+ verify(allocated == DOMID_INVALID,
+ "TEST 4: expected %u allocated %u\n", DOMID_INVALID, allocated);
+ }
+
+ /* Re-allocate first ID from [1..DOMID_FIRST_RESERVED/2]. */
+ for ( expected = 1; expected < DOMID_FIRST_RESERVED / 2; expected++ )
+ domid_free(expected);
+ for ( expected = 1; expected < DOMID_FIRST_RESERVED / 2; expected++ )
+ {
+ allocated = domid_alloc(DOMID_INVALID);
+ verify(allocated == expected,
+ "TEST 5: expected %u allocated %u\n", expected, allocated);
+ }
+
+ /* Re-allocate last ID from [1..DOMID_FIRST_RESERVED - 1]. */
+ expected = DOMID_FIRST_RESERVED - 1;
+ domid_free(DOMID_FIRST_RESERVED - 1);
+ allocated = domid_alloc(DOMID_INVALID);
+ verify(allocated == expected,
+ "TEST 6: expected %u allocated %u\n", expected, allocated);
+
+ /* Allocate an invalid ID. */
+ expected = DOMID_INVALID;
+ allocated = domid_alloc(DOMID_FIRST_RESERVED);
+ verify(allocated == expected,
+ "TEST 7: expected %u allocated %u\n", expected, allocated);
+
+ return 0;
+}
+
+/*
+ * Local variables:
+ * mode: C
+ * c-file-style: "BSD"
+ * c-basic-offset: 4
+ * indent-tabs-mode: nil
+ * End:
+ */
diff --git a/xen/lib/find-next-bit.c b/xen/lib/find-next-bit.c
index 9b8d7814f20c..539c7f2022b0 100644
--- a/xen/lib/find-next-bit.c
+++ b/xen/lib/find-next-bit.c
@@ -8,8 +8,13 @@
* as published by the Free Software Foundation; either version
* 2 of the License, or (at your option) any later version.
*/
+
+#ifdef __XEN_TOOLS__
+#include <xen-tools/bitops.h>
+#else
#include <xen/bitops.h>
#include <xen/byteorder.h>
+#endif
#define __ffs(x) (ffsl(x) - 1)
#define ffz(x) __ffs(~(x))
--
2.34.1
