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Diffstat (limited to '')
| -rw-r--r-- | tools/testing/selftests/powerpc/tm/tm-signal-context-chk-vsx.c | 184 |
1 files changed, 184 insertions, 0 deletions
diff --git a/tools/testing/selftests/powerpc/tm/tm-signal-context-chk-vsx.c b/tools/testing/selftests/powerpc/tm/tm-signal-context-chk-vsx.c new file mode 100644 index 000000000..8e25e2072 --- /dev/null +++ b/tools/testing/selftests/powerpc/tm/tm-signal-context-chk-vsx.c @@ -0,0 +1,184 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright 2016, Cyril Bur, IBM Corp. + * + * 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 (referred too as + * first and second contexts). + * Expected behaviour is that the checkpointed state is in the user + * context passed to the signal handler (first context). The speculated + * state can be accessed with the uc_link pointer (second context). + * + * 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 <stdlib.h> +#include <stdio.h> +#include <string.h> +#include <signal.h> +#include <unistd.h> + +#include <altivec.h> + +#include "utils.h" +#include "tm.h" + +#define MAX_ATTEMPT 500000 + +#define NV_VSX_REGS 12 /* Number of VSX registers to check. */ +#define VSX20 20 /* First VSX register to check in vsr20-vsr31 subset */ +#define FPR20 20 /* FPR20 overlaps VSX20 most significant doubleword */ + +long tm_signal_self_context_load(pid_t pid, long *gprs, double *fps, vector int *vms, vector int *vss); + +static sig_atomic_t fail, broken; + +/* Test only 12 vsx registers from vsr20 to vsr31 */ +vector int vsxs[] = { + /* First context will be set with these values, i.e. non-speculative */ + /* VSX20 , VSX21 , ... */ + { 1, 2, 3, 4},{ 5, 6, 7, 8},{ 9,10,11,12}, + {13,14,15,16},{17,18,19,20},{21,22,23,24}, + {25,26,27,28},{29,30,31,32},{33,34,35,36}, + {37,38,39,40},{41,42,43,44},{45,46,47,48}, + /* Second context will be set with these values, i.e. speculative */ + /* VSX20 , VSX21 , ... */ + {-1, -2, -3, -4 },{-5, -6, -7, -8 },{-9, -10,-11,-12}, + {-13,-14,-15,-16},{-17,-18,-19,-20},{-21,-22,-23,-24}, + {-25,-26,-27,-28},{-29,-30,-31,-32},{-33,-34,-35,-36}, + {-37,-38,-39,-40},{-41,-42,-43,-44},{-45,-46,-47,-48} +}; + +static void signal_usr1(int signum, siginfo_t *info, void *uc) +{ + int i, j; + uint8_t vsx[sizeof(vector int)]; + uint8_t vsx_tm[sizeof(vector int)]; + ucontext_t *ucp = uc; + ucontext_t *tm_ucp = ucp->uc_link; + + /* + * FP registers and VMX registers overlap the VSX registers. + * + * FP registers (f0-31) overlap the most significant 64 bits of VSX + * registers vsr0-31, whilst VMX registers vr0-31, being 128-bit like + * the VSX registers, overlap fully the other half of VSX registers, + * i.e. vr0-31 overlaps fully vsr32-63. + * + * Due to compatibility and historical reasons (VMX/Altivec support + * appeared first on the architecture), VMX registers vr0-31 (so VSX + * half vsr32-63 too) are stored right after the v_regs pointer, in an + * area allocated for 'vmx_reverse' array (please see + * arch/powerpc/include/uapi/asm/sigcontext.h for details about the + * mcontext_t structure on Power). + * + * The other VSX half (vsr0-31) is hence stored below vr0-31/vsr32-63 + * registers, but only the least significant 64 bits of vsr0-31. The + * most significant 64 bits of vsr0-31 (f0-31), as it overlaps the FP + * registers, is kept in fp_regs. + * + * v_regs is a 16 byte aligned pointer at the start of vmx_reserve + * (vmx_reserve may or may not be 16 aligned) where the v_regs structure + * exists, so v_regs points to where vr0-31 / vsr32-63 registers are + * fully stored. Since v_regs type is elf_vrregset_t, v_regs + 1 + * skips all the slots used to store vr0-31 / vsr32-64 and points to + * part of one VSX half, i.e. v_regs + 1 points to the least significant + * 64 bits of vsr0-31. The other part of this half (the most significant + * part of vsr0-31) is stored in fp_regs. + * + */ + /* Get pointer to least significant doubleword of vsr0-31 */ + long *vsx_ptr = (long *)(ucp->uc_mcontext.v_regs + 1); + long *tm_vsx_ptr = (long *)(tm_ucp->uc_mcontext.v_regs + 1); + + /* Check first context. Print all mismatches. */ + for (i = 0; i < NV_VSX_REGS; i++) { + /* + * Copy VSX most significant doubleword from fp_regs and + * copy VSX least significant one from 64-bit slots below + * saved VMX registers. + */ + memcpy(vsx, &ucp->uc_mcontext.fp_regs[FPR20 + i], 8); + memcpy(vsx + 8, &vsx_ptr[VSX20 + i], 8); + + fail = memcmp(vsx, &vsxs[i], sizeof(vector int)); + + if (fail) { + broken = 1; + printf("VSX%d (1st context) == 0x", VSX20 + i); + for (j = 0; j < 16; j++) + printf("%02x", vsx[j]); + printf(" instead of 0x"); + for (j = 0; j < 4; j++) + printf("%08x", vsxs[i][j]); + printf(" (expected)\n"); + } + } + + /* Check second context. Print all mismatches. */ + for (i = 0; i < NV_VSX_REGS; i++) { + /* + * Copy VSX most significant doubleword from fp_regs and + * copy VSX least significant one from 64-bit slots below + * saved VMX registers. + */ + memcpy(vsx_tm, &tm_ucp->uc_mcontext.fp_regs[FPR20 + i], 8); + memcpy(vsx_tm + 8, &tm_vsx_ptr[VSX20 + i], 8); + + fail = memcmp(vsx_tm, &vsxs[NV_VSX_REGS + i], sizeof(vector int)); + + if (fail) { + broken = 1; + printf("VSX%d (2nd context) == 0x", VSX20 + i); + for (j = 0; j < 16; j++) + printf("%02x", vsx_tm[j]); + printf(" instead of 0x"); + for (j = 0; j < 4; j++) + printf("%08x", vsxs[NV_VSX_REGS + i][j]); + printf("(expected)\n"); + } + } +} + +static int tm_signal_context_chk() +{ + 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 && !broken) { + /* + * tm_signal_self_context_load will set both first and second + * contexts accordingly to the values passed through non-NULL + * array pointers to it, in that case 'vsxs', and invoke the + * signal handler installed for SIGUSR1. + */ + rc = tm_signal_self_context_load(pid, NULL, NULL, NULL, vsxs); + FAIL_IF(rc != pid); + i++; + } + + return (broken); +} + +int main(void) +{ + return test_harness(tm_signal_context_chk, "tm_signal_context_chk_vsx"); +} |