[PATCH v3] tests: Add test for the futex syscall
Eugene Syromyatnikov
evgsyr at gmail.com
Tue Aug 30 21:32:58 UTC 2016
* tests/futex.c: New file.
* tests/futex.test: Likewise.
* tests/Makefile.am (check_PROGRAMS): Add futex.
(DECODER_TESTS): Add futex.test.
---
Changes since v2:
* Commands not available on the old kernels (2.6.18 onwards) are wrapped in
CHECK_FUTEX_ENOSYS which prevents failure in case errno is ENOSYS and is not
expected one.
* Checks for PI mutexes do no rely on PID 2 being kthreadd (which is not true
when process namespaces are employed, for example).
* Printing return code is done via retstr() which utilizes errno2name for errno
printing.
* All headers except asm/unistd.h moved under ifdef __NR_futex.
* <linux/futex.h> inclusion removed since it is proven broken in some
distros
* Added definitions for FUTEX_PRIVATE_FLAG, FUTEX_CLOCK_REALTIME, FUTEX_CMD_MASK
* Skip on EPERM since it is sometimes returned for otherwise perfectly
valid commands (WAKE_OP on AArch64)
* Minor formatting fixes.
tests/Makefile.am | 2 +
tests/futex.c | 692 +++++++++++++++++++++++++++++++++++++++++++++++++++++
tests/futex.test | 8 +
3 files changed, 702 insertions(+)
create mode 100644 tests/futex.c
create mode 100755 tests/futex.test
diff --git a/tests/Makefile.am b/tests/Makefile.am
index 0c28f06..93ed37f 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -125,6 +125,7 @@ check_PROGRAMS = \
fsync \
ftruncate \
ftruncate64 \
+ futex \
futimesat \
get_mempolicy \
getcwd \
@@ -457,6 +458,7 @@ DECODER_TESTS = \
ftruncate.test \
ftruncate64.test \
futimesat.test \
+ futex.test \
get_mempolicy.test \
getcwd.test \
getdents.test \
diff --git a/tests/futex.c b/tests/futex.c
new file mode 100644
index 0000000..dd6955e
--- /dev/null
+++ b/tests/futex.c
@@ -0,0 +1,692 @@
+#include "tests.h"
+
+#include <asm/unistd.h>
+
+#ifdef __NR_futex
+
+# include <errno.h>
+# include <stdarg.h>
+# include <stdbool.h>
+# include <stdio.h>
+# include <stdint.h>
+# include <unistd.h>
+
+# include <sys/time.h>
+
+# ifndef FUTEX_PRIVATE_FLAG
+# define FUTEX_PRIVATE_FLAG 128
+# endif
+# ifndef FUTEX_CLOCK_REALTIME
+# define FUTEX_CLOCK_REALTIME 256
+# endif
+# ifndef FUTEX_CMD_MASK
+# define FUTEX_CMD_MASK ~(FUTEX_PRIVATE_FLAG | FUTEX_CLOCK_REALTIME)
+# endif
+
+# include "xlat.h"
+# include "xlat/futexops.h"
+# include "xlat/futexwakeops.h"
+# include "xlat/futexwakecmps.h"
+
+static struct timespec *tmout;
+
+void futex_error(int *uaddr, int op, unsigned long val, unsigned long timeout,
+ int *uaddr2, unsigned long val3, int rc)
+{
+ perror_msg_and_fail("futex(%p, %#x, %#x, %#lx, %p, %#x) = %d",
+ uaddr, op, (unsigned)val, timeout, uaddr, (unsigned)val3, rc);
+}
+
+# define CHECK_FUTEX_GENERIC(uaddr, op, val, timeout, uaddr2, val3, check, \
+ enosys) \
+ do { \
+ rc = syscall(__NR_futex, (uaddr), (op), (val), (timeout), \
+ (uaddr2), (val3)); \
+ /* It is here due to EPERM on WAKE_OP on AArch64 */ \
+ if ((rc == -1) && (errno == EPERM)) \
+ break; \
+ if (enosys && (rc == -1) && (errno == ENOSYS)) \
+ break; \
+ if (!(check)) \
+ futex_error((uaddr), (op), (val), \
+ (unsigned long)(timeout), (int *)(uaddr2), \
+ (val3), rc); \
+ } while (0)
+
+# define CHECK_FUTEX_ENOSYS(uaddr, op, val, timeout, uaddr2, val3, check) \
+ CHECK_FUTEX_GENERIC(uaddr, op, val, timeout, uaddr2, val3, check, 1)
+
+# define CHECK_FUTEX(uaddr, op, val, timeout, uaddr2, val3, check) \
+ CHECK_FUTEX_GENERIC(uaddr, op, val, timeout, uaddr2, val3, check, 0)
+
+enum argmask {
+ ARG3 = 1 << 0,
+ ARG4 = 1 << 1,
+ ARG5 = 1 << 2,
+ ARG6 = 1 << 3,
+};
+
+void invalid_op(int *val, int op, uint32_t argmask, ...)
+{
+ static const unsigned long args[] = {
+ (unsigned long)0xface1e55deadbee1ULL,
+ (unsigned long)0xface1e56deadbee2ULL,
+ (unsigned long)0xface1e57deadbee3ULL,
+ (unsigned long)0xface1e58deadbee4ULL,
+ };
+ /* Since timeout value is copied before full op check, we should provide
+ * some valid timeout address or NULL */
+ int cmd = op & FUTEX_CMD_MASK;
+ bool valid_timeout = (cmd == FUTEX_WAIT) || (cmd == FUTEX_LOCK_PI) ||
+ (cmd == FUTEX_WAIT_BITSET) || (cmd == FUTEX_WAIT_REQUEUE_PI);
+ bool timeout_is_val2 = (cmd == FUTEX_REQUEUE) ||
+ (cmd == FUTEX_CMP_REQUEUE) || (cmd == FUTEX_WAKE_OP) ||
+ (cmd == FUTEX_CMP_REQUEUE_PI);
+ const char *fmt;
+ int saved_errno;
+ int rc;
+ int i;
+ va_list ap;
+
+
+ CHECK_FUTEX(val, op, args[0], valid_timeout ? 0 : args[1], args[2],
+ args[3], (rc == -1) && (errno == ENOSYS));
+ saved_errno = errno;
+ printf("futex(%p, %#x /* FUTEX_??? */", val, op);
+
+ va_start(ap, argmask);
+
+ for (i = 0; i < 4; i++) {
+ if (argmask & (1 << i)) {
+ fmt = va_arg(ap, const char *);
+
+ printf(", ");
+
+ if (((1 << i) == ARG3) || ((1 << i) == ARG6) ||
+ (((1 << i) == ARG4) && timeout_is_val2))
+ printf(fmt, (unsigned)args[i]);
+ else
+ printf(fmt, args[i]);
+ }
+ }
+
+ va_end(ap);
+
+ errno = saved_errno;
+ printf(") = -1 ENOSYS (%m)\n");
+}
+
+const char *retstr(int rc)
+{
+ enum { RES_BUF_SIZE = 256 };
+ static char buf[RES_BUF_SIZE];
+
+ if (rc == 0)
+ return "0";
+
+ snprintf(buf, sizeof(buf), "-1 %s (%m)", errno2name());
+
+ return buf;
+}
+
+# define CHECK_INVALID_CLOCKRT(op, ...) \
+ do { \
+ invalid_op(uaddr, FUTEX_CLOCK_REALTIME | (op), __VA_ARGS__); \
+ invalid_op(uaddr, FUTEX_CLOCK_REALTIME | FUTEX_PRIVATE_FLAG | \
+ (op), __VA_ARGS__); \
+ } while (0)
+
+/* Value which differs from one stored in int *val */
+# define VAL ((unsigned long)0xbadda7a0facefeedLLU)
+# define VAL_PR ((unsigned)VAL)
+
+# define VAL2 ((unsigned long)0xbadda7a0ca7b100dLLU)
+# define VAL2_PR ((unsigned)VAL2)
+
+# define VAL3 ((unsigned long)0xbadda7a09caffee1LLU)
+# define VAL3_PR ((unsigned)VAL3)
+
+int
+main(int argc, char *argv[])
+{
+ int *uaddr = tail_alloc(sizeof(*uaddr));
+ int *uaddr2 = tail_alloc(sizeof(*uaddr2));
+ int rc;
+ unsigned i;
+ unsigned j;
+
+ uaddr[0] = 0x1deadead;
+ uaddr2[0] = 0xbadf00d;
+
+ tmout = tail_alloc(sizeof(*tmout));
+ tmout->tv_sec = 123;
+ tmout->tv_nsec = 0xbadc0de;
+
+ /* FUTEX_WAIT - check whether uaddr == val and sleep
+ * Possible flags: PRIVATE, CLOCK_RT (since 4.5)
+ * 1. uaddr - futex address
+ * 2. op - FUTEX_WAIT
+ * 3. val - expected value
+ * 4. timeout - address to timespec with timeout
+ * 5. uaddr2 - not used
+ * 6. val3 - not used
+ */
+
+ /* uaddr is NULL */
+ CHECK_FUTEX(NULL, FUTEX_WAIT, VAL, tmout, uaddr2, VAL3,
+ (rc == -1) && (errno == EFAULT));
+ printf("futex(NULL, FUTEX_WAIT, %u, {%jd, %jd}) = %s\n",
+ VAL_PR, (intmax_t)tmout->tv_sec, (intmax_t)tmout->tv_nsec,
+ retstr(rc));
+
+ /* uaddr is faulty */
+ CHECK_FUTEX(uaddr + 1, FUTEX_WAIT, VAL, tmout, uaddr2, VAL3,
+ (rc == -1) && (errno == EFAULT));
+ printf("futex(%p, FUTEX_WAIT, %u, {%jd, %jd}) = %s\n",
+ uaddr + 1, VAL_PR, (intmax_t)tmout->tv_sec,
+ (intmax_t)tmout->tv_nsec, retstr(rc));
+
+ /* timeout is faulty */
+ CHECK_FUTEX(uaddr, FUTEX_WAIT, VAL, tmout + 1, uaddr2, VAL3,
+ (rc == -1) && (errno == EFAULT));
+ printf("futex(%p, FUTEX_WAIT, %u, %p) = %s\n",
+ uaddr, 0xfacefeed, tmout + 1, retstr(rc));
+
+ /* uaddr is not as provided; uaddr2 is faulty but ignored */
+ CHECK_FUTEX(uaddr, FUTEX_WAIT, VAL, tmout, uaddr2 + 1, VAL3,
+ (rc == -1) && (errno == EAGAIN));
+ printf("futex(%p, FUTEX_WAIT, %u, {%jd, %jd}) = %s\n",
+ uaddr, VAL_PR, (intmax_t)tmout->tv_sec,
+ (intmax_t)tmout->tv_nsec, retstr(rc));
+
+ /* uaddr is not as provided; uaddr2 is faulty but ignored */
+ CHECK_FUTEX_ENOSYS(uaddr, FUTEX_PRIVATE_FLAG | FUTEX_WAIT, VAL, tmout,
+ uaddr2 + 1, VAL3, (rc == -1) && (errno == EAGAIN));
+ printf("futex(%p, FUTEX_WAIT_PRIVATE, %u, {%jd, %jd}) = %s\n",
+ uaddr, VAL_PR, (intmax_t)tmout->tv_sec,
+ (intmax_t)tmout->tv_nsec, retstr(rc));
+
+ /* Next 2 tests are with CLOCKRT bit set */
+
+ /* Valid after v4.4-rc2-27-g337f130 */
+ CHECK_FUTEX_ENOSYS(uaddr,
+ FUTEX_CLOCK_REALTIME | FUTEX_WAIT,
+ VAL, tmout, uaddr2, VAL3, (rc == -1) && (errno == EAGAIN));
+ printf("futex(%p, FUTEX_WAIT|FUTEX_CLOCK_REALTIME, %u, "
+ "{%jd, %jd}) = %s\n", uaddr, VAL_PR,
+ (intmax_t)tmout->tv_sec, (intmax_t)tmout->tv_nsec, retstr(rc));
+
+ CHECK_FUTEX_ENOSYS(uaddr,
+ FUTEX_CLOCK_REALTIME | FUTEX_PRIVATE_FLAG | FUTEX_WAIT ,
+ VAL, tmout, uaddr2, 0, (rc == -1) && (errno == EAGAIN));
+ printf("futex(%p, FUTEX_WAIT_PRIVATE|FUTEX_CLOCK_REALTIME, %u, "
+ "{%jd, %jd}) = %s\n", uaddr, VAL_PR,
+ (intmax_t)tmout->tv_sec, (intmax_t)tmout->tv_nsec, retstr(rc));
+
+ /* FUTEX_WAIT_BITSET - FUTEX_WAIT which provides additional bitmask
+ * which should be matched at least in one bit with
+ * wake mask in order to wake.
+ * Possible flags: PRIVATE, CLOCKRT
+ * 1. uaddr - futex address
+ * 2. op - FUTEX_TRYLOCK_PI
+ * 3. val - expected value stored in uaddr
+ * 4. timeout - timeout
+ * 5. uaddr2 - not used
+ * 6. val3 - bitmask
+ */
+
+ CHECK_FUTEX_ENOSYS(uaddr, FUTEX_WAIT_BITSET, VAL, tmout, uaddr2 + 1,
+ VAL3, (rc == -1) && (errno == EAGAIN));
+ printf("futex(%p, FUTEX_WAIT_BITSET, %u, {%jd, %jd}, %#x) = %s\n",
+ uaddr, VAL_PR, (intmax_t)tmout->tv_sec,
+ (intmax_t)tmout->tv_nsec, VAL3_PR, retstr(rc));
+
+ /* val3 of 0 is invalid */
+ CHECK_FUTEX_ENOSYS(uaddr, FUTEX_WAIT_BITSET, VAL, tmout, uaddr2 + 1, 0,
+ (rc == -1) && (errno == EINVAL));
+ printf("futex(%p, FUTEX_WAIT_BITSET, %u, {%jd, %jd}, %#x) = %s\n",
+ uaddr, VAL_PR, (intmax_t)tmout->tv_sec,
+ (intmax_t)tmout->tv_nsec, 0, retstr(rc));
+
+ CHECK_FUTEX_ENOSYS(uaddr, FUTEX_PRIVATE_FLAG | FUTEX_WAIT_BITSET, VAL,
+ tmout, uaddr2 + 1, VAL3, (rc == -1) && (errno == EAGAIN));
+ printf("futex(%p, FUTEX_WAIT_BITSET_PRIVATE, %u, {%jd, %jd}, %#x) = "
+ "%s\n", uaddr, VAL_PR, (intmax_t)tmout->tv_sec,
+ (intmax_t)tmout->tv_nsec, VAL3_PR, retstr(rc));
+
+ /* Next 3 tests are with CLOCKRT bit set */
+
+ CHECK_FUTEX_ENOSYS(uaddr, FUTEX_CLOCK_REALTIME | FUTEX_WAIT_BITSET, VAL,
+ tmout, uaddr2 + 1, VAL3, (rc == -1) && (errno == EAGAIN));
+ printf("futex(%p, FUTEX_WAIT_BITSET|FUTEX_CLOCK_REALTIME, %u, "
+ "{%jd, %jd}, %#x) = %s\n", uaddr, VAL_PR,
+ (intmax_t)tmout->tv_sec, (intmax_t)tmout->tv_nsec, VAL3_PR,
+ retstr(rc));
+
+ /* val3 of 0 is invalid */
+ CHECK_FUTEX_ENOSYS(uaddr, FUTEX_CLOCK_REALTIME | FUTEX_WAIT_BITSET, VAL,
+ tmout, uaddr2 + 1, 0, (rc == -1) && (errno == EINVAL));
+ printf("futex(%p, FUTEX_WAIT_BITSET|FUTEX_CLOCK_REALTIME, %u, "
+ "{%jd, %jd}, %#x) = %s\n", uaddr, VAL_PR,
+ (intmax_t)tmout->tv_sec, (intmax_t)tmout->tv_nsec, 0,
+ retstr(rc));
+
+ CHECK_FUTEX_ENOSYS(uaddr, FUTEX_CLOCK_REALTIME | FUTEX_PRIVATE_FLAG |
+ FUTEX_WAIT_BITSET, VAL, tmout, uaddr2 + 1, VAL3,
+ (rc == -1) && (errno == EAGAIN));
+ printf("futex(%p, FUTEX_WAIT_BITSET_PRIVATE|FUTEX_CLOCK_REALTIME, %u, "
+ "{%jd, %jd}, %#x) = %s\n", uaddr, VAL_PR,
+ (intmax_t)tmout->tv_sec, (intmax_t)tmout->tv_nsec, VAL3_PR,
+ retstr(rc));
+
+ /* FUTEX_WAKE - wake val processes waiting for uaddr
+ * Possible flags: PRIVATE
+ * 1. uaddr - futex address
+ * 2. op - FUTEX_WAKE
+ * 3. val - how many processes to wake
+ * 4. timeout - not used
+ * 5. uaddr2 - not used
+ * 6. val3 - not used
+ */
+
+ /* Zero processes to wake is not a good idea, but it should return 0 */
+ CHECK_FUTEX(uaddr, FUTEX_WAKE, 0, NULL, NULL, 0, (rc == 0));
+ printf("futex(%p, FUTEX_WAKE, %u) = %s\n", uaddr, 0, retstr(rc));
+
+ /* Trying to wake some processes, but there's nothing to wake */
+ CHECK_FUTEX(uaddr, FUTEX_WAKE, 10, NULL, NULL, 0, (rc == 0));
+ printf("futex(%p, FUTEX_WAKE, %u) = %s\n", uaddr, 10, retstr(rc));
+
+ /* Trying to wake some processes, but there's nothing to wake */
+ CHECK_FUTEX_ENOSYS(uaddr, FUTEX_PRIVATE_FLAG | FUTEX_WAKE, 10, NULL,
+ NULL, 0, (rc == 0));
+ printf("futex(%p, FUTEX_WAKE_PRIVATE, %u) = %s\n", uaddr, 10,
+ retstr(rc));
+
+ CHECK_INVALID_CLOCKRT(FUTEX_WAKE, ARG3, "%u");
+
+ /* FUTEX_WAKE_BITSET - wake val processes waiting for uaddr which has at
+ * least one common bit with bitset provided in
+ * val3.
+ * Possible flags: PRIVATE
+ * 1. uaddr - futex address
+ * 2. op - FUTEX_WAKE
+ * 3. val - how many processes to wake
+ * 4. timeout - not used
+ * 5. uaddr2 - not used
+ * 6. val3 - bitmask
+ */
+
+ /* Trying to wake some processes, but there's nothing to wake */
+ CHECK_FUTEX_ENOSYS(uaddr, FUTEX_WAKE_BITSET, 10, NULL, NULL,
+ VAL3, (rc == 0));
+ printf("futex(%p, FUTEX_WAKE_BITSET, %u, %#x) = %s\n", uaddr, 10,
+ VAL3_PR, retstr(rc));
+
+ /* bitset 0 is invalid */
+ CHECK_FUTEX_ENOSYS(uaddr, FUTEX_WAKE_BITSET, 10, NULL, NULL, 0,
+ (rc == -1) && (errno == EINVAL));
+ printf("futex(%p, FUTEX_WAKE_BITSET, %u, %#x) = %s\n", uaddr, 10, 0,
+ retstr(rc));
+
+ /* Trying to wake some processes, but there's nothing to wake */
+ CHECK_FUTEX_ENOSYS(uaddr, FUTEX_PRIVATE_FLAG | FUTEX_WAKE_BITSET, 10,
+ NULL, NULL, VAL3, (rc == 0));
+ printf("futex(%p, FUTEX_WAKE_BITSET_PRIVATE, %u, %#x) = %s\n", uaddr,
+ 10, VAL3_PR, retstr(rc));
+
+ CHECK_INVALID_CLOCKRT(FUTEX_WAKE_BITSET, ARG3 | ARG6, "%u", "%#x");
+
+ /* FUTEX_FD - deprecated
+ * Possible flags: PRIVATE
+ * 1. uaddr - futex address
+ * 2. op - FUTEX_FD
+ * 3. val - signal number
+ * 4. timeout - not used
+ * 5. uaddr2 - not used
+ * 6. val3 - not used
+ */
+
+ /* FUTEX_FD is not implemented since 2.6.26 */
+ CHECK_FUTEX_ENOSYS(uaddr, FUTEX_FD, VAL, NULL, NULL, VAL3,
+ (rc == -1) && (errno == EINVAL));
+ printf("futex(%p, FUTEX_FD, %u) = %s\n", uaddr, VAL_PR, retstr(rc));
+
+ /* FUTEX_FD is not implemented since 2.6.26 */
+ CHECK_FUTEX_ENOSYS(uaddr, FUTEX_PRIVATE_FLAG | FUTEX_FD, VAL, NULL,
+ NULL, VAL3, (rc == -1) && (errno == EINVAL));
+ printf("futex(%p, FUTEX_FD|FUTEX_PRIVATE_FLAG, %u) = %s\n", uaddr,
+ VAL_PR, retstr(rc));
+
+ CHECK_INVALID_CLOCKRT(FUTEX_FD, ARG3, "%u");
+
+ /* FUTEX_REQUEUE - wake val processes and re-queue rest on uaddr2
+ * Possible flags: PRIVATE
+ * 1. uaddr - futex address
+ * 2. op - FUTEX_REQUEUE
+ * 3. val - how many processes to wake
+ * 4. val2 - amount of processes to re-queue on uadr2
+ * 5. uaddr2 - another futex address, to re-queue waiting processes on
+ * 6. val3 - not used
+ */
+
+ /* Trying to re-queue some processes but there's nothing to re-queue */
+ CHECK_FUTEX(uaddr, FUTEX_REQUEUE, VAL, VAL2, uaddr2, VAL3,
+ (rc == 0));
+ printf("futex(%p, FUTEX_REQUEUE, %u, %u, %p) = %s\n",
+ uaddr, VAL_PR, VAL2_PR, uaddr2, retstr(rc));
+
+ /* Trying to re-queue some processes but there's nothing to re-queue */
+ CHECK_FUTEX_ENOSYS(uaddr, FUTEX_PRIVATE_FLAG | FUTEX_REQUEUE, VAL, VAL2,
+ uaddr2, VAL3, (rc == 0));
+ printf("futex(%p, FUTEX_REQUEUE_PRIVATE, %u, %u, %p) = %s\n",
+ uaddr, VAL_PR, VAL2_PR, uaddr2, retstr(rc));
+
+ CHECK_INVALID_CLOCKRT(FUTEX_REQUEUE, ARG3 | ARG4 | ARG5, "%u", "%u",
+ "%#lx");
+
+ /* FUTEX_CMP_REQUEUE - wake val processes and re-queue rest on uaddr2
+ * if uaddr has value val3
+ * Possible flags: PRIVATE
+ * 1. uaddr - futex address
+ * 2. op - FUTEX_CMP_REQUEUE
+ * 3. val - how many processes to wake
+ * 4. val2 - amount of processes to re-queue on uadr2
+ * 5. uaddr2 - another futex address, to re-queue waiting processes on
+ * 6. val3 - expected value stored in uaddr
+ */
+
+ /* Comparison re-queue with wrong val value */
+ CHECK_FUTEX(uaddr, FUTEX_CMP_REQUEUE, VAL, VAL2, uaddr2, VAL3,
+ (rc == -1) && (errno == EAGAIN));
+ printf("futex(%p, FUTEX_CMP_REQUEUE, %u, %u, %p, %u) = %s\n",
+ uaddr, VAL_PR, VAL2_PR, uaddr2, VAL3_PR, retstr(rc));
+
+ /* Successful comparison re-queue */
+ CHECK_FUTEX(uaddr, FUTEX_CMP_REQUEUE, VAL, VAL2, uaddr2, *uaddr,
+ (rc == 0));
+ printf("futex(%p, FUTEX_CMP_REQUEUE, %u, %u, %p, %u) = %s\n",
+ uaddr, VAL_PR, VAL2_PR, uaddr2, *uaddr, retstr(rc));
+
+ /* Successful comparison re-queue */
+ CHECK_FUTEX_ENOSYS(uaddr, FUTEX_PRIVATE_FLAG | FUTEX_CMP_REQUEUE, VAL,
+ VAL2, uaddr2, *uaddr, (rc == 0));
+ printf("futex(%p, FUTEX_CMP_REQUEUE_PRIVATE, %u, %u, %p, %u) = %s\n",
+ uaddr, VAL_PR, VAL2_PR, uaddr2, *uaddr, retstr(rc));
+
+ CHECK_INVALID_CLOCKRT(FUTEX_CMP_REQUEUE, ARG3 | ARG4 | ARG5 | ARG6,
+ "%u", "%u", "%#lx", "%u");
+
+ /* FUTEX_WAKE_OP - wake val processes waiting for uaddr, additionally
+ * wake val2 processes waiting for uaddr2 in case
+ * operation encoded in val3 (change of value at uaddr2
+ * and comparison of previous value against provided
+ * constant) succeedes with value at uaddr2. Operation
+ * result is written to value of uaddr2 (in any case).
+ * 1. uaddr - futex address
+ * 2. op - FUTEX_WAKE_OP
+ * 3. val - how many processes to wake
+ * 4. val2 - amount of processes to wake in case operation encoded in
+ * val3 returns true
+ * 5. uaddr2 - another futex address, for conditional wake of
+ * additional processes
+ * 6. val3 - encoded operation:
+ * 1. bit 31 - if 1 then value stored in field field 4
+ * should be interpreted as power of 2.
+ * 2. 28..30 - arithmetic operation which should be
+ * applied to previous value stored in
+ * uaddr2. Values available (from 2005 up to
+ * 2016): SET. ADD, OR, ANDN, XOR.
+ * 3. 24..29 - comparison operation which should be
+ * applied to the old value stored in uaddr2
+ * (before arithmetic operation is applied).
+ * Possible values: EQ, NE, LT, LE, GT, GE.
+ * 4. 12..23 - Second operand for arithmetic operation.
+ * If bit 31 is set, it is interpreted as
+ * power of 2.
+ * 5. 00..11 - Value against which old value stored in
+ * uaddr2 is compared.
+ */
+
+ static const struct {
+ uint32_t val;
+ const char *str;
+ int err;
+ const char *errstr;
+ } wake_ops[] = {
+ { 0x00000000, "{FUTEX_OP_SET, 0, FUTEX_OP_CMP_EQ, 0}" },
+ { 0x00fff000, "{FUTEX_OP_SET, 4095, FUTEX_OP_CMP_EQ, 0}" },
+ { 0x00000fff, "{FUTEX_OP_SET, 0, FUTEX_OP_CMP_EQ, 4095}" },
+ { 0x00ffffff, "{FUTEX_OP_SET, 4095, FUTEX_OP_CMP_EQ, 4095}" },
+ { 0x10000000, "{FUTEX_OP_ADD, 0, FUTEX_OP_CMP_EQ, 0}" },
+ { 0x20000000, "{FUTEX_OP_OR, 0, FUTEX_OP_CMP_EQ, 0}" },
+ { 0x30000000, "{FUTEX_OP_ANDN, 0, FUTEX_OP_CMP_EQ, 0}" },
+ { 0x40000000, "{FUTEX_OP_XOR, 0, FUTEX_OP_CMP_EQ, 0}" },
+ { 0x50000000, "{0x5 /* FUTEX_OP_??? */, 0, FUTEX_OP_CMP_EQ, 0}",
+ ENOSYS, "ENOSYS" },
+ { 0x70000000, "{0x7 /* FUTEX_OP_??? */, 0, FUTEX_OP_CMP_EQ, 0}",
+ ENOSYS, "ENOSYS" },
+ { 0x80000000, "{FUTEX_OP_OPARG_SHIFT|FUTEX_OP_SET, 0, "
+ "FUTEX_OP_CMP_EQ, 0}" },
+ { 0xa0caffee, "{FUTEX_OP_OPARG_SHIFT|FUTEX_OP_OR, 3247, "
+ "FUTEX_OP_CMP_EQ, 4078}" },
+ { 0x01000000, "{FUTEX_OP_SET, 0, FUTEX_OP_CMP_NE, 0}" },
+ { 0x01234567, "{FUTEX_OP_SET, 564, FUTEX_OP_CMP_NE, 1383}" },
+ { 0x02000000, "{FUTEX_OP_SET, 0, FUTEX_OP_CMP_LT, 0}" },
+ { 0x03000000, "{FUTEX_OP_SET, 0, FUTEX_OP_CMP_LE, 0}" },
+ { 0x04000000, "{FUTEX_OP_SET, 0, FUTEX_OP_CMP_GT, 0}" },
+ { 0x05000000, "{FUTEX_OP_SET, 0, FUTEX_OP_CMP_GE, 0}" },
+ { 0x06000000, "{FUTEX_OP_SET, 0, 0x6 /* FUTEX_OP_CMP_??? */, "
+ "0}", ENOSYS, "ENOSYS" },
+ { 0x07000000, "{FUTEX_OP_SET, 0, 0x7 /* FUTEX_OP_CMP_??? */, "
+ "0}", ENOSYS, "ENOSYS" },
+ { 0x08000000, "{FUTEX_OP_SET, 0, 0x8 /* FUTEX_OP_CMP_??? */, "
+ "0}", ENOSYS, "ENOSYS" },
+ { 0x0f000000, "{FUTEX_OP_SET, 0, 0xf /* FUTEX_OP_CMP_??? */, "
+ "0}", ENOSYS, "ENOSYS" },
+ { 0xbadfaced, "{FUTEX_OP_OPARG_SHIFT|FUTEX_OP_ANDN, "
+ "3578, 0xa /* FUTEX_OP_CMP_??? */, 3309}", ENOSYS,
+ "ENOSYS" },
+ { 0xffffffff, "{FUTEX_OP_OPARG_SHIFT|0x7 /* FUTEX_OP_??? */, "
+ "4095, 0xf /* FUTEX_OP_CMP_??? */, 4095}", ENOSYS,
+ "ENOSYS" },
+ };
+
+ for (i = 0; i < ARRAY_SIZE(wake_ops); i++) {
+ for (j = 0; j < 2; j++) {
+ CHECK_FUTEX_ENOSYS(uaddr,
+ j ? FUTEX_WAKE_OP_PRIVATE : FUTEX_WAKE_OP,
+ VAL, i, uaddr2, wake_ops[i].val, (rc == 0));
+ printf("futex(%p, FUTEX_WAKE_OP%s, %u, %u, %p, %s) = "
+ "%s\n", uaddr, j ? "_PRIVATE" : "", VAL_PR, i,
+ uaddr2, wake_ops[i].str, retstr(rc));
+ }
+ }
+
+ CHECK_INVALID_CLOCKRT(FUTEX_WAKE_OP, ARG3 | ARG4 | ARG5 | ARG6,
+ "%u", "%u", "%#lx",
+ /* Decoding of the 0xdeadbee4 value */
+ "{FUTEX_OP_OPARG_SHIFT|0x5 /* FUTEX_OP_??? */, 2779, "
+ "0xe /* FUTEX_OP_CMP_??? */, 3812}");
+
+ /* FUTEX_LOCK_PI - slow path for mutex lock with process inheritance
+ * support. Expect that futex has 0 in unlocked case and
+ * TID of owning process in locked case. Value can also
+ * contain FUTEX_WAITERS bit signalling the presence of
+ * waiters queue.
+ * Possible flags: PRIVATE
+ * 1. uaddr - futex address
+ * 2. op - FUTEX_LOCK_PI
+ * 3. val - not used
+ * 4. timeout - timeout
+ * 5. uaddr2 - not used
+ * 6. val3 - not used
+ */
+
+ *uaddr = getpid();
+
+ CHECK_FUTEX_ENOSYS(uaddr + 1, FUTEX_LOCK_PI, VAL, tmout, uaddr2 + 1,
+ VAL3, (rc == -1) && (errno == EFAULT));
+ printf("futex(%p, FUTEX_LOCK_PI, {%jd, %jd}) = %s\n",
+ uaddr + 1, (intmax_t)tmout->tv_sec, (intmax_t)tmout->tv_nsec,
+ retstr(rc));
+
+ CHECK_FUTEX_ENOSYS(uaddr + 1, FUTEX_PRIVATE_FLAG | FUTEX_LOCK_PI, VAL,
+ tmout, uaddr2 + 1, VAL3, (rc == -1) && (errno == EFAULT));
+ printf("futex(%p, FUTEX_LOCK_PI_PRIVATE, {%jd, %jd}) = %s\n",
+ uaddr + 1, (intmax_t)tmout->tv_sec, (intmax_t)tmout->tv_nsec,
+ retstr(rc));
+
+ /* NULL is passed by invalid_op() in cases valid timeout address is
+ * needed */
+ CHECK_INVALID_CLOCKRT(FUTEX_LOCK_PI, ARG4, "NULL");
+
+ /* FUTEX_UNLOCK_PI - slow path for mutex unlock with process inheritance
+ * support. Expected to be called by process in case
+ * it failed to execute fast path (it usually means
+ * that FUTEX_WAITERS flag had been set while the lock
+ * has been held).
+ * Possible flags: PRIVATE
+ * 1. uaddr - futex address
+ * 2. op - FUTEX_UNLOCK_PI
+ * 3. val - not used
+ * 4. timeout - not used
+ * 5. uaddr2 - not used
+ * 6. val3 - not used
+ */
+
+ CHECK_FUTEX_ENOSYS(uaddr + 1, FUTEX_UNLOCK_PI, VAL, tmout, uaddr2 + 1,
+ VAL3, (rc == -1) && (errno == EFAULT));
+ printf("futex(%p, FUTEX_UNLOCK_PI) = %s\n", uaddr + 1, retstr(rc));
+
+ CHECK_FUTEX_ENOSYS(uaddr + 1, FUTEX_PRIVATE_FLAG | FUTEX_UNLOCK_PI, VAL,
+ tmout, uaddr2 + 1, VAL3, (rc == -1) && (errno == EFAULT));
+ printf("futex(%p, FUTEX_UNLOCK_PI_PRIVATE) = %s\n", uaddr +1,
+ retstr(rc));
+
+ CHECK_INVALID_CLOCKRT(FUTEX_UNLOCK_PI, 0);
+
+ /* FUTEX_TRYLOCK_PI - slow path for mutex trylock with process
+ * inheritance support.
+ * Possible flags: PRIVATE
+ * 1. uaddr - futex address
+ * 2. op - FUTEX_TRYLOCK_PI
+ * 3. val - not used
+ * 4. timeout - not used
+ * 5. uaddr2 - not used
+ * 6. val3 - not used
+ */
+
+ CHECK_FUTEX_ENOSYS(uaddr + 1, FUTEX_TRYLOCK_PI, VAL, tmout, uaddr2 + 1,
+ VAL3, (rc == -1) && (errno == EFAULT));
+ printf("futex(%p, FUTEX_TRYLOCK_PI) = %s\n", uaddr + 1, retstr(rc));
+
+ CHECK_FUTEX_ENOSYS(uaddr + 1, FUTEX_PRIVATE_FLAG | FUTEX_TRYLOCK_PI,
+ VAL, tmout, uaddr2 + 1, VAL3, (rc == -1) && (errno == EFAULT));
+ printf("futex(%p, FUTEX_TRYLOCK_PI_PRIVATE) = %s\n", uaddr + 1,
+ retstr(rc));
+
+ CHECK_INVALID_CLOCKRT(FUTEX_TRYLOCK_PI, 0);
+
+ /* FUTEX_WAIT_REQUEUE_PI - kernel-side handling of special case when
+ * processes should be re-queued on PI-aware
+ * futexes. This is so special since PI futexes
+ * utilize rt_mutex and it should be at no time
+ * left free with a wait queue, so this should
+ * be performed atomically in-kernel.
+ * Possible flags: PRIVATE, CLOCKRT
+ * 1. uaddr - futex address
+ * 2. op - FUTEX_WAIT_REQUEUE_PI
+ * 3. val - expected value stored in uaddr
+ * 4. timeout - timeout
+ * 5. uaddr2 - (PI-aware) futex address to requeue process on
+ * 6. val3 - not used (in kernel, it always initialized to
+ * FUTEX_BITSET_MATCH_ANY and passed to
+ * futex_wait_requeue_pi())
+ */
+
+ CHECK_FUTEX_ENOSYS(uaddr, FUTEX_WAIT_REQUEUE_PI, VAL, tmout, uaddr2,
+ VAL3, (rc == -1) && (errno == EAGAIN));
+ printf("futex(%p, FUTEX_WAIT_REQUEUE_PI, %u, {%jd, %jd}, %p) = %s\n",
+ uaddr, VAL_PR, (intmax_t)tmout->tv_sec,
+ (intmax_t)tmout->tv_nsec, uaddr2, retstr(rc));
+
+ CHECK_FUTEX_ENOSYS(uaddr, FUTEX_PRIVATE_FLAG | FUTEX_WAIT_REQUEUE_PI,
+ VAL, tmout, uaddr2, VAL3, (rc == -1) && (errno == EAGAIN));
+ printf("futex(%p, FUTEX_WAIT_REQUEUE_PI_PRIVATE, %u, {%jd, %jd}, %p) "
+ "= %s\n", uaddr, VAL_PR, (intmax_t)tmout->tv_sec,
+ (intmax_t)tmout->tv_nsec, uaddr2, retstr(rc));
+
+ CHECK_FUTEX_ENOSYS(uaddr, FUTEX_CLOCK_REALTIME | FUTEX_WAIT_REQUEUE_PI,
+ VAL, tmout, uaddr2, VAL3, (rc == -1) && (errno == EAGAIN));
+ printf("futex(%p, FUTEX_WAIT_REQUEUE_PI|FUTEX_CLOCK_REALTIME, %u, "
+ "{%jd, %jd}, %p) = %s\n", uaddr, VAL_PR,
+ (intmax_t)tmout->tv_sec, (intmax_t)tmout->tv_nsec, uaddr2,
+ retstr(rc));
+
+ CHECK_FUTEX_ENOSYS(uaddr, FUTEX_CLOCK_REALTIME | FUTEX_PRIVATE_FLAG |
+ FUTEX_WAIT_REQUEUE_PI, VAL, tmout, uaddr2, VAL3,
+ (rc == -1) && (errno == EAGAIN));
+ printf("futex(%p, FUTEX_WAIT_REQUEUE_PI_PRIVATE|FUTEX_CLOCK_REALTIME, "
+ "%u, {%jd, %jd}, %p) = %s\n", uaddr, VAL_PR,
+ (intmax_t)tmout->tv_sec, (intmax_t)tmout->tv_nsec, uaddr2,
+ retstr(rc));
+
+ /* FUTEX_CMP_REQUEUE_PI - version of FUTEX_CMP_REQUEUE which re-queues
+ * on PI-aware futex.
+ * Possible flags: PRIVATE
+ * 1. uaddr - futex address
+ * 2. op - FUTEX_CMP_REQUEUE
+ * 3. val - how many processes to wake
+ * 4. val2 - amount of processes to re-queue on uadr2
+ * 5. uaddr2 - (PI-aware) futex address, to re-queue waiting processes
+ * on
+ * 6. val3 - expected value stored in uaddr
+ */
+
+ /* All these should fail with EINVAL since we try to re-queue to non-PI
+ * futex.
+ */
+
+ CHECK_FUTEX_ENOSYS(uaddr, FUTEX_CMP_REQUEUE_PI, VAL, VAL2, uaddr2, VAL3,
+ (rc == -1) && (errno == EINVAL));
+ printf("futex(%p, FUTEX_CMP_REQUEUE_PI, %u, %u, %p, %u) = %s\n",
+ uaddr, VAL_PR, VAL2_PR, uaddr2, VAL3_PR, retstr(rc));
+
+ CHECK_FUTEX_ENOSYS(uaddr, FUTEX_CMP_REQUEUE_PI, VAL, VAL2, uaddr2,
+ *uaddr, (rc == -1) && (errno == EINVAL));
+ printf("futex(%p, FUTEX_CMP_REQUEUE_PI, %u, %u, %p, %u) = %s\n",
+ uaddr, VAL_PR, VAL2_PR, uaddr2, *uaddr, retstr(rc));
+
+ CHECK_FUTEX_ENOSYS(uaddr, FUTEX_PRIVATE_FLAG | FUTEX_CMP_REQUEUE_PI,
+ VAL, VAL2, uaddr2, *uaddr, (rc == -1) && (errno == EINVAL));
+ printf("futex(%p, FUTEX_CMP_REQUEUE_PI_PRIVATE, %u, %u, %p, %u) = %s\n",
+ uaddr, VAL_PR, VAL2_PR, uaddr2, *uaddr, retstr(rc));
+
+ CHECK_INVALID_CLOCKRT(FUTEX_CMP_REQUEUE_PI, ARG3 | ARG4 | ARG5 | ARG6,
+ "%u", "%u", "%#lx", "%u");
+
+ /*
+ * Unknown commands
+ */
+
+ CHECK_FUTEX(uaddr, 0xd, VAL, tmout + 1, uaddr2 + 1, VAL3,
+ (rc == -1) && (errno == ENOSYS));
+ printf("futex(%p, 0xd /* FUTEX_??? */, %u, %p, %p, %#x) = %s\n",
+ uaddr, VAL_PR, tmout + 1, uaddr2 + 1, VAL3_PR, retstr(rc));
+
+ CHECK_FUTEX(uaddr, 0xbefeeded, VAL, tmout + 1, uaddr2, VAL3,
+ (rc == -1) && (errno == ENOSYS));
+ printf("futex(%p, 0xbefeeded /* FUTEX_??? */, %u, %p, %p, %#x) = %s\n",
+ uaddr, VAL_PR, tmout + 1, uaddr2, VAL3_PR, retstr(rc));
+
+ puts("+++ exited with 0 +++");
+
+ return 0;
+}
+
+#else
+
+SKIP_MAIN_UNDEFINED("__NR_futex")
+
+#endif
diff --git a/tests/futex.test b/tests/futex.test
new file mode 100755
index 0000000..8248cf3
--- /dev/null
+++ b/tests/futex.test
@@ -0,0 +1,8 @@
+#!/bin/sh
+
+# Check futex syscall decoding.
+
+. "${srcdir=.}/init.sh"
+
+run_strace_match_diff -efutex -a1
+run_strace_match_diff -efutex -v -a1
--
1.7.10.4
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