linux/linux-5.4.31/tools/testing/selftests/powerpc/tm/tm-signal-context-chk-gpr.c

113 lines
3.2 KiB
C

// 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 <signal.h>
#include <unistd.h>
#include <altivec.h>
#include "utils.h"
#include "tm.h"
#define MAX_ATTEMPT 500000
#define NV_GPR_REGS 18 /* Number of non-volatile GPR registers */
#define R14 14 /* First non-volatile register to check in r14-r31 subset */
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 non-volatile general purpose registers, i.e. r14-r31 */
static long gprs[] = {
/* First context will be set with these values, i.e. non-speculative */
/* R14, R15, ... */
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18,
/* Second context will be set with these values, i.e. speculative */
/* R14, R15, ... */
-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;
/* Check first context. Print all mismatches. */
for (i = 0; i < NV_GPR_REGS; i++) {
fail = (ucp->uc_mcontext.gp_regs[R14 + i] != gprs[i]);
if (fail) {
broken = 1;
printf("GPR%d (1st context) == %lu instead of %lu (expected)\n",
R14 + i, ucp->uc_mcontext.gp_regs[R14 + i], gprs[i]);
}
}
/* Check second context. Print all mismatches. */
for (i = 0; i < NV_GPR_REGS; i++) {
fail = (tm_ucp->uc_mcontext.gp_regs[R14 + i] != gprs[NV_GPR_REGS + i]);
if (fail) {
broken = 1;
printf("GPR%d (2nd context) == %lu instead of %lu (expected)\n",
R14 + i, tm_ucp->uc_mcontext.gp_regs[R14 + i], gprs[NV_GPR_REGS + i]);
}
}
}
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 && !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 'gprs', and invoke the
* signal handler installed for SIGUSR1.
*/
rc = tm_signal_self_context_load(pid, gprs, NULL, NULL, NULL);
FAIL_IF(rc != pid);
i++;
}
return broken;
}
int main(void)
{
return test_harness(tm_signal_context_chk_gpr, "tm_signal_context_chk_gpr");
}