linux/tools/testing/selftests/powerpc/ptrace/ptrace-tm-vsx.c
Michael Ellerman a02cbc7ffe selftests/powerpc: Fixup clobbers for TM tests
Some of our TM (Transactional Memory) tests, list "r1" (the stack
pointer) as a clobbered register.

GCC >= 9 doesn't accept this, and the build breaks:

  ptrace-tm-spd-tar.c: In function 'tm_spd_tar':
  ptrace-tm-spd-tar.c:31:2: error: listing the stack pointer register 'r1' in a clobber list is deprecated [-Werror=deprecated]
     31 |  asm __volatile__(
        |  ^~~
  ptrace-tm-spd-tar.c:31:2: note: the value of the stack pointer after an 'asm' statement must be the same as it was before the statement

We do have some fairly large inline asm blocks in these tests, and
some of them do change the value of r1. However they should all return
to C with the value in r1 restored, so I think it's legitimate to say
r1 is not clobbered.

As Segher points out, the r1 clobbers may have been added because of
the use of `or 1,1,1`, however that doesn't actually clobber r1.

Segher also points out that some of these tests do clobber LR, because
they call functions, and that is not listed in the clobbers, so add
that where appropriate.

Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20191029095324.14669-1-mpe@ellerman.id.au
2019-10-29 20:53:49 +11:00

164 lines
3.1 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Ptrace test for VMX/VSX registers in the TM context
*
* Copyright (C) 2015 Anshuman Khandual, IBM Corporation.
*/
#include "ptrace.h"
#include "tm.h"
#include "ptrace-vsx.h"
int shm_id;
unsigned long *cptr, *pptr;
unsigned long fp_load[VEC_MAX];
unsigned long fp_store[VEC_MAX];
unsigned long fp_load_ckpt[VEC_MAX];
unsigned long fp_load_ckpt_new[VEC_MAX];
__attribute__((used)) void load_vsx(void)
{
loadvsx(fp_load, 0);
}
__attribute__((used)) void load_vsx_ckpt(void)
{
loadvsx(fp_load_ckpt, 0);
}
void tm_vsx(void)
{
unsigned long result, texasr;
int ret;
cptr = (unsigned long *)shmat(shm_id, NULL, 0);
trans:
cptr[1] = 0;
asm __volatile__(
"bl load_vsx_ckpt;"
"1: ;"
"tbegin.;"
"beq 2f;"
"bl load_vsx;"
"tsuspend.;"
"li 7, 1;"
"stw 7, 0(%[cptr1]);"
"tresume.;"
"b .;"
"tend.;"
"li 0, 0;"
"ori %[res], 0, 0;"
"b 3f;"
"2: ;"
"li 0, 1;"
"ori %[res], 0, 0;"
"mfspr %[texasr], %[sprn_texasr];"
"3: ;"
: [res] "=r" (result), [texasr] "=r" (texasr)
: [sprn_texasr] "i" (SPRN_TEXASR), [cptr1] "b" (&cptr[1])
: "memory", "r0", "r3", "r4",
"r7", "r8", "r9", "r10", "r11", "lr"
);
if (result) {
if (!cptr[0])
goto trans;
shmdt((void *)cptr);
storevsx(fp_store, 0);
ret = compare_vsx_vmx(fp_store, fp_load_ckpt_new);
if (ret)
exit(1);
exit(0);
}
shmdt((void *)cptr);
exit(1);
}
int trace_tm_vsx(pid_t child)
{
unsigned long vsx[VSX_MAX];
unsigned long vmx[VMX_MAX + 2][2];
FAIL_IF(start_trace(child));
FAIL_IF(show_vsx(child, vsx));
FAIL_IF(validate_vsx(vsx, fp_load));
FAIL_IF(show_vmx(child, vmx));
FAIL_IF(validate_vmx(vmx, fp_load));
FAIL_IF(show_vsx_ckpt(child, vsx));
FAIL_IF(validate_vsx(vsx, fp_load_ckpt));
FAIL_IF(show_vmx_ckpt(child, vmx));
FAIL_IF(validate_vmx(vmx, fp_load_ckpt));
memset(vsx, 0, sizeof(vsx));
memset(vmx, 0, sizeof(vmx));
load_vsx_vmx(fp_load_ckpt_new, vsx, vmx);
FAIL_IF(write_vsx_ckpt(child, vsx));
FAIL_IF(write_vmx_ckpt(child, vmx));
pptr[0] = 1;
FAIL_IF(stop_trace(child));
return TEST_PASS;
}
int ptrace_tm_vsx(void)
{
pid_t pid;
int ret, status, i;
SKIP_IF(!have_htm());
shm_id = shmget(IPC_PRIVATE, sizeof(int) * 2, 0777|IPC_CREAT);
for (i = 0; i < 128; i++) {
fp_load[i] = 1 + rand();
fp_load_ckpt[i] = 1 + 2 * rand();
fp_load_ckpt_new[i] = 1 + 3 * rand();
}
pid = fork();
if (pid < 0) {
perror("fork() failed");
return TEST_FAIL;
}
if (pid == 0)
tm_vsx();
if (pid) {
pptr = (unsigned long *)shmat(shm_id, NULL, 0);
while (!pptr[1])
asm volatile("" : : : "memory");
ret = trace_tm_vsx(pid);
if (ret) {
kill(pid, SIGKILL);
shmdt((void *)pptr);
shmctl(shm_id, IPC_RMID, NULL);
return TEST_FAIL;
}
shmdt((void *)pptr);
ret = wait(&status);
shmctl(shm_id, IPC_RMID, NULL);
if (ret != pid) {
printf("Child's exit status not captured\n");
return TEST_FAIL;
}
return (WIFEXITED(status) && WEXITSTATUS(status)) ? TEST_FAIL :
TEST_PASS;
}
return TEST_PASS;
}
int main(int argc, char *argv[])
{
return test_harness(ptrace_tm_vsx, "ptrace_tm_vsx");
}