powerpc/ptrace: Enable support for Performance Monitor registers

This patch enables support for Performance monitor registers related
ELF core note NT_PPC_PMU based ptrace requests through
PTRACE_GETREGSET, PTRACE_SETREGSET calls. This is achieved
through adding one new register sets REGSET_PMU in powerpc
corresponding to the ELF core note sections added in this
regard. It also implements the get, set and active functions
for this new register sets added.

Signed-off-by: Anshuman Khandual <khandual@linux.vnet.ibm.com>
Signed-off-by: Simon Guo <wei.guo.simon@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
This commit is contained in:
Anshuman Khandual 2016-07-28 10:57:44 +08:00 committed by Michael Ellerman
parent cf89d4e1b1
commit a67ae75802
2 changed files with 77 additions and 1 deletions

View file

@ -95,6 +95,7 @@
#define ELF_NVSX 32 /* includes all VSX registers */
#define ELF_NTMSPRREG 3 /* include tfhar, tfiar, texasr */
#define ELF_NEBB 3 /* includes ebbrr, ebbhr, bescr */
#define ELF_NPMU 5 /* includes siar, sdar, sier, mmcr2, mmcr0 */
typedef unsigned long elf_greg_t64;
typedef elf_greg_t64 elf_gregset_t64[ELF_NGREG];

View file

@ -1824,6 +1824,75 @@ static int ebb_set(struct task_struct *target,
return ret;
}
static int pmu_active(struct task_struct *target,
const struct user_regset *regset)
{
if (!cpu_has_feature(CPU_FTR_ARCH_207S))
return -ENODEV;
return regset->n;
}
static int pmu_get(struct task_struct *target,
const struct user_regset *regset,
unsigned int pos, unsigned int count,
void *kbuf, void __user *ubuf)
{
/* Build tests */
BUILD_BUG_ON(TSO(siar) + sizeof(unsigned long) != TSO(sdar));
BUILD_BUG_ON(TSO(sdar) + sizeof(unsigned long) != TSO(sier));
BUILD_BUG_ON(TSO(sier) + sizeof(unsigned long) != TSO(mmcr2));
BUILD_BUG_ON(TSO(mmcr2) + sizeof(unsigned long) != TSO(mmcr0));
if (!cpu_has_feature(CPU_FTR_ARCH_207S))
return -ENODEV;
return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
&target->thread.siar, 0,
5 * sizeof(unsigned long));
}
static int pmu_set(struct task_struct *target,
const struct user_regset *regset,
unsigned int pos, unsigned int count,
const void *kbuf, const void __user *ubuf)
{
int ret = 0;
/* Build tests */
BUILD_BUG_ON(TSO(siar) + sizeof(unsigned long) != TSO(sdar));
BUILD_BUG_ON(TSO(sdar) + sizeof(unsigned long) != TSO(sier));
BUILD_BUG_ON(TSO(sier) + sizeof(unsigned long) != TSO(mmcr2));
BUILD_BUG_ON(TSO(mmcr2) + sizeof(unsigned long) != TSO(mmcr0));
if (!cpu_has_feature(CPU_FTR_ARCH_207S))
return -ENODEV;
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
&target->thread.siar, 0,
sizeof(unsigned long));
if (!ret)
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
&target->thread.sdar, sizeof(unsigned long),
2 * sizeof(unsigned long));
if (!ret)
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
&target->thread.sier, 2 * sizeof(unsigned long),
3 * sizeof(unsigned long));
if (!ret)
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
&target->thread.mmcr2, 3 * sizeof(unsigned long),
4 * sizeof(unsigned long));
if (!ret)
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
&target->thread.mmcr0, 4 * sizeof(unsigned long),
5 * sizeof(unsigned long));
return ret;
}
#endif
/*
* These are our native regset flavors.
@ -1857,6 +1926,7 @@ enum powerpc_regset {
#ifdef CONFIG_PPC_BOOK3S_64
REGSET_TAR, /* TAR register */
REGSET_EBB, /* EBB registers */
REGSET_PMR, /* Performance Monitor Registers */
#endif
};
@ -1957,6 +2027,11 @@ static const struct user_regset native_regsets[] = {
.size = sizeof(u64), .align = sizeof(u64),
.active = ebb_active, .get = ebb_get, .set = ebb_set
},
[REGSET_PMR] = {
.core_note_type = NT_PPC_PMU, .n = ELF_NPMU,
.size = sizeof(u64), .align = sizeof(u64),
.active = pmu_active, .get = pmu_get, .set = pmu_set
},
#endif
};