This test uses a signal to 'discard' a transaction. That is, it will take a signal of a thread in a suspended transaction and just remove the suspended MSR bit. Because this will send the userspace thread back to the tebgin + 4 address, we should also set CR0 to be nice.
Signed-off-by: Cyril Bur <cyril...@gmail.com> --- tools/testing/selftests/powerpc/tm/Makefile | 1 + .../powerpc/tm/tm-signal-drop-transaction.c | 74 ++++++++++++++++++++++ 2 files changed, 75 insertions(+) create mode 100644 tools/testing/selftests/powerpc/tm/tm-signal-drop-transaction.c diff --git a/tools/testing/selftests/powerpc/tm/Makefile b/tools/testing/selftests/powerpc/tm/Makefile index a23453943ad2..7a1e53297588 100644 --- a/tools/testing/selftests/powerpc/tm/Makefile +++ b/tools/testing/selftests/powerpc/tm/Makefile @@ -4,6 +4,7 @@ SIGNAL_CONTEXT_CHK_TESTS := tm-signal-context-chk-gpr tm-signal-context-chk-fpu TEST_GEN_PROGS := tm-resched-dscr tm-syscall tm-signal-msr-resv tm-signal-stack \ tm-vmxcopy tm-fork tm-tar tm-tmspr tm-vmx-unavail tm-unavailable tm-trap \ + tm-signal-drop-transaction \ $(SIGNAL_CONTEXT_CHK_TESTS) include ../../lib.mk diff --git a/tools/testing/selftests/powerpc/tm/tm-signal-drop-transaction.c b/tools/testing/selftests/powerpc/tm/tm-signal-drop-transaction.c new file mode 100644 index 000000000000..a8397f7e7faa --- /dev/null +++ b/tools/testing/selftests/powerpc/tm/tm-signal-drop-transaction.c @@ -0,0 +1,74 @@ +/* + * Copyright 2018, Cyril Bur, IBM Corp. + * Licensed under GPLv2. + * + * This test uses a signal handler to make a thread go from + * transactional state to nothing state. In practice userspace, why + * would userspace ever do this? In theory, they can. + */ + +#include <errno.h> +#include <inttypes.h> +#include <pthread.h> +#include <signal.h> +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> + +#include "utils.h" +#include "tm.h" + +static bool passed; + +static void signal_usr1(int signum, siginfo_t *info, void *uc) +{ + ucontext_t *ucp = uc; + struct pt_regs *regs = ucp->uc_mcontext.regs; + + passed = true; + + /* I really hope I got that right, we wan't to clear both the MSR_TS bits */ + regs->msr &= ~(3ULL << 33); + /* Set CR0 to 0b0010 */ + regs->ccr &= ~(0xDULL << 28); +} + +int test_drop(void) +{ + struct sigaction act; + + SKIP_IF(!have_htm()); + + act.sa_sigaction = signal_usr1; + sigemptyset(&act.sa_mask); + act.sa_flags = SA_SIGINFO; + if (sigaction(SIGUSR1, &act, NULL) < 0) { + perror("sigaction sigusr1"); + exit(1); + } + + + asm __volatile__( + "tbegin.;" + "beq 1f; " + "tsuspend.;" + "1: ;" + : : : "memory", "cr0"); + + if (!passed && !tcheck_transactional()) { + fprintf(stderr, "Not in suspended state: 0x%1x\n", tcheck()); + exit(1); + } + + kill(getpid(), SIGUSR1); + + /* If we reach here, we've passed. Otherwise we've probably crashed + * the kernel */ + + return 0; +} + +int main(int argc, char *argv[]) +{ + return test_harness(test_drop, "tm_signal_drop_transaction"); +} -- 2.16.2