From f10d4424b20c101f3b4dd599819083e1e4b5a3fa Mon Sep 17 00:00:00 2001 From: Cyril Bur Date: Fri, 23 Sep 2016 16:18:20 +1000 Subject: [PATCH] selftests/powerpc: Add checks for transactional GPRs in signal contexts If a thread receives a signal while transactional the kernel creates a second context to show the transactional state of the process. This test loads some known values and waits for a signal and confirms that the expected values are in the signal context. Signed-off-by: Cyril Bur Signed-off-by: Michael Ellerman --- tools/testing/selftests/powerpc/tm/Makefile | 7 +- .../powerpc/tm/tm-signal-context-chk-gpr.c | 90 ++++++++++++++++ tools/testing/selftests/powerpc/tm/tm-signal.S | 114 +++++++++++++++++++++ 3 files changed, 210 insertions(+), 1 deletion(-) create mode 100644 tools/testing/selftests/powerpc/tm/tm-signal-context-chk-gpr.c create mode 100644 tools/testing/selftests/powerpc/tm/tm-signal.S diff --git a/tools/testing/selftests/powerpc/tm/Makefile b/tools/testing/selftests/powerpc/tm/Makefile index 9d301d7..e1204f6 100644 --- a/tools/testing/selftests/powerpc/tm/Makefile +++ b/tools/testing/selftests/powerpc/tm/Makefile @@ -1,5 +1,7 @@ +SIGNAL_CONTEXT_CHK_TESTS := tm-signal-context-chk-gpr + TEST_PROGS := tm-resched-dscr tm-syscall tm-signal-msr-resv tm-signal-stack \ - tm-vmxcopy tm-fork tm-tar tm-tmspr tm-exec tm-execed + tm-vmxcopy tm-fork tm-tar tm-tmspr $(SIGNAL_CONTEXT_CHK_TESTS) all: $(TEST_PROGS) @@ -11,6 +13,9 @@ tm-syscall: tm-syscall-asm.S tm-syscall: CFLAGS += -I../../../../../usr/include tm-tmspr: CFLAGS += -pthread +$(SIGNAL_CONTEXT_CHK_TESTS): tm-signal.S +$(SIGNAL_CONTEXT_CHK_TESTS): CFLAGS += -mhtm -m64 -mvsx + include ../../lib.mk clean: diff --git a/tools/testing/selftests/powerpc/tm/tm-signal-context-chk-gpr.c b/tools/testing/selftests/powerpc/tm/tm-signal-context-chk-gpr.c new file mode 100644 index 0000000..df91330 --- /dev/null +++ b/tools/testing/selftests/powerpc/tm/tm-signal-context-chk-gpr.c @@ -0,0 +1,90 @@ +/* + * Copyright 2016, Cyril Bur, IBM Corp. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + * + * + * Test the kernel's signal frame code. + * + * The kernel sets up two sets of ucontexts if the signal was to be + * delivered while the thread was in a transaction. + * Expected behaviour is that the checkpointed state is in the user + * context passed to the signal handler. The speculated state can be + * accessed with the uc_link pointer. + * + * The rationale for this is that if TM unaware code (which linked + * against TM libs) installs a signal handler it will not know of the + * speculative nature of the 'live' registers and may infer the wrong + * thing. + */ + +#include +#include +#include +#include + +#include + +#include "utils.h" +#include "tm.h" + +#define MAX_ATTEMPT 500000 + +#define NV_GPR_REGS 18 + +long tm_signal_self_context_load(pid_t pid, long *gprs, double *fps, vector int *vms, vector int *vss); + +static sig_atomic_t fail; + +static long gps[] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, + -1,-2,-3,-4,-5,-6,-7,-8,-9,-10,-11,-12,-13,-14,-15,-16,-17,-18}; + +static void signal_usr1(int signum, siginfo_t *info, void *uc) +{ + int i; + ucontext_t *ucp = uc; + ucontext_t *tm_ucp = ucp->uc_link; + + for (i = 0; i < NV_GPR_REGS && !fail; i++) { + fail = (ucp->uc_mcontext.gp_regs[i + 14] != gps[i]); + fail |= (tm_ucp->uc_mcontext.gp_regs[i + 14] != gps[i + NV_GPR_REGS]); + if (fail) + printf("Failed on %d GPR %lu or %lu\n", i, + ucp->uc_mcontext.gp_regs[i + 14], tm_ucp->uc_mcontext.gp_regs[i + 14]); + } +} + +static int tm_signal_context_chk_gpr() +{ + struct sigaction act; + int i; + long rc; + pid_t pid = getpid(); + + 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); + } + + i = 0; + while (i < MAX_ATTEMPT && !fail) { + rc = tm_signal_self_context_load(pid, gps, NULL, NULL, NULL); + FAIL_IF(rc != pid); + i++; + } + + return fail; +} + +int main(void) +{ + return test_harness(tm_signal_context_chk_gpr, "tm_signal_context_chk_gpr"); +} diff --git a/tools/testing/selftests/powerpc/tm/tm-signal.S b/tools/testing/selftests/powerpc/tm/tm-signal.S new file mode 100644 index 0000000..4e13e8b --- /dev/null +++ b/tools/testing/selftests/powerpc/tm/tm-signal.S @@ -0,0 +1,114 @@ +/* + * Copyright 2015, Cyril Bur, IBM Corp. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#include "../basic_asm.h" +#include "../gpr_asm.h" +#include "../fpu_asm.h" +#include "../vmx_asm.h" +#include "../vsx_asm.h" + +/* + * Large caveat here being that the caller cannot expect the + * signal to always be sent! The hardware can (AND WILL!) abort + * the transaction between the tbegin and the tsuspend (however + * unlikely it seems or infrequently it actually happens). + * You have been warned. + */ +/* long tm_signal_self(pid_t pid, long *gprs, double *fps, vector *vms, vector *vss); */ +FUNC_START(tm_signal_self_context_load) + PUSH_BASIC_STACK(512) + /* + * Don't strictly need to save and restore as it depends on if + * we're going to use them, however this reduces messy logic + */ + PUSH_VMX(STACK_FRAME_LOCAL(5,0),r8) + PUSH_FPU(512) + PUSH_NVREGS_BELOW_FPU(512) + std r3, STACK_FRAME_PARAM(0)(sp) /* pid */ + std r4, STACK_FRAME_PARAM(1)(sp) /* gps */ + std r5, STACK_FRAME_PARAM(2)(sp) /* fps */ + std r6, STACK_FRAME_PARAM(3)(sp) /* vms */ + std r7, STACK_FRAME_PARAM(4)(sp) /* vss */ + + ld r3, STACK_FRAME_PARAM(1)(sp) + cmpdi r3, 0 + beq skip_gpr_lc + bl load_gpr +skip_gpr_lc: + ld r3, STACK_FRAME_PARAM(2)(sp) + cmpdi r3, 0 + beq skip_fpu_lc + bl load_fpu +skip_fpu_lc: + ld r3, STACK_FRAME_PARAM(3)(sp) + cmpdi r3, 0 + beq skip_vmx_lc + bl load_vmx +skip_vmx_lc: + ld r3, STACK_FRAME_PARAM(4)(sp) + cmpdi r3, 0 + beq skip_vsx_lc + bl load_vsx +skip_vsx_lc: + /* + * Set r3 (return value) before tbegin. Use the pid as a known + * 'all good' return value, zero is used to indicate a non-doomed + * transaction. + */ + ld r3, STACK_FRAME_PARAM(0)(sp) + tbegin. + beq 1f + tsuspend. /* Can't enter a syscall transactionally */ + ld r3, STACK_FRAME_PARAM(1)(sp) + cmpdi r3, 0 + beq skip_gpr_lt + /* Get the second half of the array */ + addi r3, r3, 8 * 18 + bl load_gpr +skip_gpr_lt: + ld r3, STACK_FRAME_PARAM(2)(sp) + cmpdi r3, 0 + beq skip_fpu_lt + /* Get the second half of the array */ + addi r3, r3, 8 * 18 + bl load_fpu +skip_fpu_lt: + ld r3, STACK_FRAME_PARAM(3)(sp) + cmpdi r3, 0 + beq skip_vmx_lt + /* Get the second half of the array */ + addi r3, r3, 16 * 12 + bl load_vmx +skip_vmx_lt: + ld r3, STACK_FRAME_PARAM(4)(sp) + cmpdi r3, 0 + beq skip_vsx_lt + /* Get the second half of the array */ + addi r3, r3, 16 * 12 + bl load_vsx +skip_vsx_lt: + li r0, 37 /* sys_kill */ + ld r3, STACK_FRAME_PARAM(0)(sp) /* pid */ + li r4, 10 /* SIGUSR1 */ + sc /* Taking the signal will doom the transaction */ + tabort. 0 + tresume. /* Be super sure we abort */ + /* + * This will cause us to resume doomed transaction and cause + * hardware to cleanup, we'll end up at 1: anything between + * tresume. and 1: shouldn't ever run. + */ + li r3, 0 + 1: + POP_VMX(STACK_FRAME_LOCAL(5,0),r4) + POP_FPU(512) + POP_NVREGS_BELOW_FPU(512) + POP_BASIC_STACK(512) + blr +FUNC_END(tm_signal_self_context_load) -- 2.7.4