Re: [PATCH V3 2/3] powerpc, ptrace: Enable support for transactional memory register sets

From: Sukadev Bhattiprolu
Date: Wed Aug 27 2014 - 17:35:31 EST


Anshuman Khandual [khandual@xxxxxxxxxxxxxxxxxx] wrote:
| This patch enables get and set of transactional memory related register
| sets through PTRACE_GETREGSET/PTRACE_SETREGSET interface by implementing
| four new powerpc specific register sets i.e REGSET_TM_SPR, REGSET_TM_CGPR,
| REGSET_TM_CFPR, REGSET_CVMX support corresponding to these following new
| ELF core note types added previously in this regard.
|
| (1) NT_PPC_TM_SPR
| (2) NT_PPC_TM_CGPR
| (3) NT_PPC_TM_CFPR
| (4) NT_PPC_TM_CVMX
|
| Signed-off-by: Anshuman Khandual <khandual@xxxxxxxxxxxxxxxxxx>
| ---
| arch/powerpc/include/asm/switch_to.h | 8 +
| arch/powerpc/kernel/process.c | 24 ++
| arch/powerpc/kernel/ptrace.c | 792 +++++++++++++++++++++++++++++++++--
| 3 files changed, 795 insertions(+), 29 deletions(-)
|
| diff --git a/arch/powerpc/include/asm/switch_to.h b/arch/powerpc/include/asm/switch_to.h
| index 0e83e7d..2737f46 100644
| --- a/arch/powerpc/include/asm/switch_to.h
| +++ b/arch/powerpc/include/asm/switch_to.h
| @@ -80,6 +80,14 @@ static inline void flush_spe_to_thread(struct task_struct *t)
| }
| #endif
|
| +#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
| +extern void flush_tmregs_to_thread(struct task_struct *);
| +#else
| +static inline void flush_tmregs_to_thread(struct task_struct *t)
| +{
| +}
| +#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
| +
| static inline void clear_task_ebb(struct task_struct *t)
| {
| #ifdef CONFIG_PPC_BOOK3S_64
| diff --git a/arch/powerpc/kernel/process.c b/arch/powerpc/kernel/process.c
| index 31d0215..e247898 100644
| --- a/arch/powerpc/kernel/process.c
| +++ b/arch/powerpc/kernel/process.c
| @@ -695,6 +695,30 @@ static inline void __switch_to_tm(struct task_struct *prev)
| }
| }
|
| +void flush_tmregs_to_thread(struct task_struct *tsk)
| +{
| + /*
| + * If task is not current, it should have been flushed
| + * already to it's thread_struct during __switch_to().
| + */
| + if (tsk != current)
| + return;
| +
| + preempt_disable();
| + if (tsk->thread.regs) {
| + /*
| + * If we are still current, the TM state need to
| + * be flushed to thread_struct as it will be still
| + * present in the current cpu.
| + */
| + if (MSR_TM_ACTIVE(tsk->thread.regs->msr)) {
| + __switch_to_tm(tsk);
| + tm_recheckpoint_new_task(tsk);
| + }
| + }
| + preempt_enable();
| +}
| +
| /*
| * This is called if we are on the way out to userspace and the
| * TIF_RESTORE_TM flag is set. It checks if we need to reload
| diff --git a/arch/powerpc/kernel/ptrace.c b/arch/powerpc/kernel/ptrace.c
| index 2e3d2bf..17642ef 100644
| --- a/arch/powerpc/kernel/ptrace.c
| +++ b/arch/powerpc/kernel/ptrace.c
| @@ -357,6 +357,17 @@ static int gpr_set(struct task_struct *target, const struct user_regset *regset,
| return ret;
| }
|
| +/*
| + * When any transaction is active, "thread_struct->transact_fp" holds
| + * the current running value of all FPR registers and "thread_struct->
| + * fp_state" holds the last checkpointed FPR registers state for the
| + * current transaction.
| + *
| + * struct data {
| + * u64 fpr[32];
| + * u64 fpscr;
| + * };
| + */

Maybe a reference to 'struct thread_fp_state' in the comments will help ?


| static int fpr_get(struct task_struct *target, const struct user_regset *regset,
| unsigned int pos, unsigned int count,
| void *kbuf, void __user *ubuf)
| @@ -365,21 +376,41 @@ static int fpr_get(struct task_struct *target, const struct user_regset *regset,
| u64 buf[33];
| int i;
| #endif
| - flush_fp_to_thread(target);
| + if (MSR_TM_ACTIVE(target->thread.regs->msr)) {
| + flush_fp_to_thread(target);
| + flush_altivec_to_thread(target);
| + flush_tmregs_to_thread(target);
| + } else {
| + flush_fp_to_thread(target);
| + }

flush_fp_to_thread(target) is uncondtional - so could be outside
the if and else blocks ?

|
| #ifdef CONFIG_VSX
| /* copy to local buffer then write that out */
| - for (i = 0; i < 32 ; i++)
| - buf[i] = target->thread.TS_FPR(i);
| - buf[32] = target->thread.fp_state.fpscr;
| + if (MSR_TM_ACTIVE(target->thread.regs->msr)) {
| + for (i = 0; i < 32 ; i++)
| + buf[i] = target->thread.TS_TRANS_FPR(i);
| + buf[32] = target->thread.transact_fp.fpscr;
| + } else {
| + for (i = 0; i < 32 ; i++)
| + buf[i] = target->thread.TS_FPR(i);
| + buf[32] = target->thread.fp_state.fpscr;
| + }
| return user_regset_copyout(&pos, &count, &kbuf, &ubuf, buf, 0, -1);
|
| #else
| - BUILD_BUG_ON(offsetof(struct thread_fp_state, fpscr) !=
| - offsetof(struct thread_fp_state, fpr[32][0]));
| + if (MSR_TM_ACTIVE(tsk->thread.regs->msr)) {
| + BUILD_BUG_ON(offsetof(struct transact_fp, fpscr) !=
| + offsetof(struct transact_fp, fpr[32][0]));

Is MSR_TM_ACTIVE() a run time check or compile time ?
ie is there a reason to move the compile time check into the if block ?

|
| - return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
| + return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
| + &target->thread.transact_fp, 0, -1);
| + } esle {
| + BUILD_BUG_ON(offsetof(struct thread_fp_state, fpscr) !=
| + offsetof(struct thread_fp_state, fpr[32][0]));
| +
| + return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
| &target->thread.fp_state, 0, -1);
| + }
| #endif
| }
|
| @@ -391,23 +422,44 @@ static int fpr_set(struct task_struct *target, const struct user_regset *regset,
| u64 buf[33];
| int i;
| #endif
| - flush_fp_to_thread(target);
| + if (MSR_TM_ACTIVE(target->thread.regs->msr)) {
| + flush_fp_to_thread(target);
| + flush_altivec_to_thread(target);
| + flush_tmregs_to_thread(target);
| + } else {
| + flush_fp_to_thread(target);
| + }
|

As mentioned above, flush_fp_to_thread() could be outside the if block.
| #ifdef CONFIG_VSX
| /* copy to local buffer then write that out */
| i = user_regset_copyin(&pos, &count, &kbuf, &ubuf, buf, 0, -1);
| if (i)
| return i;
| - for (i = 0; i < 32 ; i++)
| - target->thread.TS_FPR(i) = buf[i];
| - target->thread.fp_state.fpscr = buf[32];
| + for (i = 0; i < 32 ; i++) {
| + if (MSR_TM_ACTIVE(target->thread.regs->msr))
| + target->thread.TS_TRANS_FPR(i) = buf[i];
| + else
| + target->thread.TS_FPR(i) = buf[i];
| + }
| + if (MSR_TM_ACTIVE(target->thread.regs->msr))
| + target->thread.transact_fp.fpscr = buf[32];
| + else
| + target->thread.fp_state.fpscr = buf[32];

I think this code is easier to read than the similar code above
in fpr_get() where you have the 'for' loop in both if and else blocks.

| return 0;
| #else
| - BUILD_BUG_ON(offsetof(struct thread_fp_state, fpscr) !=
| - offsetof(struct thread_fp_state, fpr[32][0]));
| + if (MSR_TM_ACTIVE(target->thread.regs->msr)) {
| + BUILD_BUG_ON(offsetof(struct transact_fp, fpscr) !=
| + offsetof(struct transact_fp, fpr[32][0]));
|
| - return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
| - &target->thread.fp_state, 0, -1);
| + return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
| + &target->thread.transact_fp, 0, -1);
| + } else {
| + BUILD_BUG_ON(offsetof(struct thread_fp_state, fpscr) !=
| + offsetof(struct thread_fp_state, fpr[32][0]));
| +
| + return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
| + &target->thread.fp_state, 0, -1);
| + }
| #endif
| }
|
| @@ -432,20 +484,44 @@ static int vr_active(struct task_struct *target,
| return target->thread.used_vr ? regset->n : 0;
| }
|
| +/*
| + * When any transaction is active, "thread_struct->transact_vr" holds
| + * the current running value of all VMX registers and "thread_struct->
| + * vr_state" holds the last checkpointed value of VMX registers for the
| + * current transaction.
| + *
| + * struct data {
| + * vector128 vr[32];
| + * vector128 vscr;
| + * vector128 vrsave;
| + * };
| + */
| static int vr_get(struct task_struct *target, const struct user_regset *regset,
| unsigned int pos, unsigned int count,
| void *kbuf, void __user *ubuf)
| {
| int ret;
| + struct thread_vr_state *addr;
|
| - flush_altivec_to_thread(target);
| + if (MSR_TM_ACTIVE(target->thread.regs->msr)) {
| + flush_fp_to_thread(target);
| + flush_altivec_to_thread(target);

Is order of flush_fp_to_thread() and flush_altivec_to_thread()
significant or can we call flush_altivec_to_thread() unconditionally
outside the if block ?
| + flush_tmregs_to_thread(target);
| + } else {
| + flush_altivec_to_thread(target);
| + }
|
| BUILD_BUG_ON(offsetof(struct thread_vr_state, vscr) !=
| offsetof(struct thread_vr_state, vr[32]));
|
| + if (MSR_TM_ACTIVE(target->thread.regs->msr))
| + addr = &target->thread.transact_vr;
| + else
| + addr = &target->thread.vr_state;
| +
| ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
| - &target->thread.vr_state, 0,
| - 33 * sizeof(vector128));
| + addr, 0, 33 * sizeof(vector128));
| +
| if (!ret) {
| /*
| * Copy out only the low-order word of vrsave.
| @@ -455,11 +531,14 @@ static int vr_get(struct task_struct *target, const struct user_regset *regset,
| u32 word;
| } vrsave;
| memset(&vrsave, 0, sizeof(vrsave));
| - vrsave.word = target->thread.vrsave;
| + if (MSR_TM_ACTIVE(target->thread.regs->msr))
| + vrsave.word = target->thread.transact_vrsave;
| + else
| + vrsave.word = target->thread.vrsave;
| +
| ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, &vrsave,
| 33 * sizeof(vector128), -1);
| }
| -
| return ret;
| }
|
| @@ -467,16 +546,27 @@ static int vr_set(struct task_struct *target, const struct user_regset *regset,
| unsigned int pos, unsigned int count,
| const void *kbuf, const void __user *ubuf)
| {
| + struct thread_vr_state *addr;
| int ret;
|
| - flush_altivec_to_thread(target);
| + if (MSR_TM_ACTIVE(target->thread.regs->msr)) {
| + flush_fp_to_thread(target);
| + flush_altivec_to_thread(target);
| + flush_tmregs_to_thread(target);
| + } else {
| + flush_altivec_to_thread(target);
| + }
|
| BUILD_BUG_ON(offsetof(struct thread_vr_state, vscr) !=
| offsetof(struct thread_vr_state, vr[32]));
|
| + if (MSR_TM_ACTIVE(target->thread.regs->msr))
| + addr = &target->thread.transact_vr;
| + else
| + addr = &target->thread.vr_state;
| ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
| - &target->thread.vr_state, 0,
| - 33 * sizeof(vector128));
| + addr, 0, 33 * sizeof(vector128));
| +
| if (!ret && count > 0) {
| /*
| * We use only the first word of vrsave.
| @@ -486,13 +576,21 @@ static int vr_set(struct task_struct *target, const struct user_regset *regset,
| u32 word;
| } vrsave;
| memset(&vrsave, 0, sizeof(vrsave));
| - vrsave.word = target->thread.vrsave;
| +
| + if (MSR_TM_ACTIVE(target->thread.regs->msr))
| + vrsave.word = target->thread.transact_vrsave;
| + else
| + vrsave.word = target->thread.vrsave;
| +
| ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &vrsave,
| 33 * sizeof(vector128), -1);
| - if (!ret)
| - target->thread.vrsave = vrsave.word;
| + if (!ret) {
| + if (MSR_TM_ACTIVE(target->thread.regs->msr))
| + target->thread.transact_vrsave = vrsave.word;
| + else
| + target->thread.vrsave = vrsave.word;
| + }
| }
| -
| return ret;
| }
| #endif /* CONFIG_ALTIVEC */
| @@ -613,6 +711,442 @@ static int evr_set(struct task_struct *target, const struct user_regset *regset,
| }
| #endif /* CONFIG_SPE */
|
| +#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
| +
| +static int tm_spr_active(struct task_struct *target,
| + const struct user_regset *regset)
| +{
| + if (!cpu_has_feature(CPU_FTR_TM))
| + return -ENODEV;
| +
| + if(!MSR_TM_ACTIVE(target->thread.regs->msr))
| + return 0;
| +
| + return regset->n;
| +}
| +/*
| + * Transactional memory SPR
| + *
| + * struct {
| + * u64 tm_tfhar;
| + * u64 tm_texasr;
| + * u64 tm_tfiar;
| + * unsigned long tm_orig_msr;
| + * unsigned long tm_tar;
| + * unsigned long tm_ppr;
| + * unsigned long tm_dscr;
| + * };
| + */
| +static int tm_spr_get(struct task_struct *target, const struct user_regset *regset,
| + unsigned int pos, unsigned int count,
| + void *kbuf, void __user *ubuf)
| +{
| + int ret;
| +
| + if (!cpu_has_feature(CPU_FTR_TM))
| + return -ENODEV;
| +
| + if(!MSR_TM_ACTIVE(target->thread.regs->msr))
| + return -ENODATA;
| +
| + flush_fp_to_thread(target);
| + flush_altivec_to_thread(target);
| + flush_tmregs_to_thread(target);
| +

Can we copy all the values ot a local buf and then do a single
copyout to user space ?

| + /* TFHAR register */
| + ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
| + &target->thread.tm_tfhar, 0, sizeof(u64));
| +
| + BUILD_BUG_ON(offsetof(struct thread_struct, tm_tfhar) +
| + sizeof(u64) != offsetof(struct thread_struct, tm_texasr));
| +
| + /* TEXASR register */
| + if (!ret)
| + ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
| + &target->thread.tm_texasr, sizeof(u64), 2 * sizeof(u64));
| +
| + BUILD_BUG_ON(offsetof(struct thread_struct, tm_texasr) +
| + sizeof(u64) != offsetof(struct thread_struct, tm_tfiar));
| +
| + /* TFIAR register */
| + if (!ret)
| + ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
| + &target->thread.tm_tfiar, 2 * sizeof(u64), 3 * sizeof(u64));
| +
| + BUILD_BUG_ON(offsetof(struct thread_struct, tm_tfiar) +
| + sizeof(u64) != offsetof(struct thread_struct, tm_orig_msr));
| +
| + /* TM checkpointed original MSR */
| + if (!ret)
| + ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
| + &target->thread.tm_orig_msr, 3 * sizeof(u64),
| + 3 * sizeof(u64) + sizeof(unsigned long));
| +
| + BUILD_BUG_ON(offsetof(struct thread_struct, tm_orig_msr) +
| + sizeof(unsigned long) + sizeof(struct pt_regs)
| + != offsetof(struct thread_struct, tm_tar));
| +
| + /* TM checkpointed TAR register */
| + if (!ret)
| + ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
| + &target->thread.tm_tar, 3 * sizeof(u64) +
| + sizeof(unsigned long) , 3 * sizeof(u64) +
| + 2 * sizeof(unsigned long));
| +
| + BUILD_BUG_ON(offsetof(struct thread_struct, tm_tar)
| + + sizeof(unsigned long) !=
| + offsetof(struct thread_struct, tm_ppr));
| +
| + /* TM checkpointed PPR register */
| + if (!ret)
| + ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
| + &target->thread.tm_ppr, 3 * sizeof(u64) +
| + 2 * sizeof(unsigned long), 3 * sizeof(u64) +
| + 3 * sizeof(unsigned long));
| +
| + BUILD_BUG_ON(offsetof(struct thread_struct, tm_ppr) +
| + sizeof(unsigned long) !=
| + offsetof(struct thread_struct, tm_dscr));
| +
| + /* TM checkpointed DSCR register */
| + if (!ret)
| + ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
| + &target->thread.tm_dscr, 3 * sizeof(u64)
| + + 3 * sizeof(unsigned long), 3 * sizeof(u64)
| + + 4 * sizeof(unsigned long));
| + return ret;
| +}
| +
| +static int tm_spr_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;
| +
| + if (!cpu_has_feature(CPU_FTR_TM))
| + return -ENODEV;
| +
| + if(!MSR_TM_ACTIVE(target->thread.regs->msr))
| + return -ENODATA;
| +
| + flush_fp_to_thread(target);
| + flush_altivec_to_thread(target);
| + flush_tmregs_to_thread(target);
| +
| + /* TFHAR register */
| + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
| + &target->thread.tm_tfhar, 0, sizeof(u64));
| +
| + BUILD_BUG_ON(offsetof(struct thread_struct, tm_tfhar)
| + + sizeof(u64) != offsetof(struct thread_struct, tm_texasr));

A single copyin into a local buffer followed by a local assignment would
be easier to read ?

It could be easier to read if all BUILD_BUG_ON() calls are in one place
maybe near the beginning of the function or in the header file.

| +
| + /* TEXASR register */
| + if (!ret)
| + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
| + &target->thread.tm_texasr, sizeof(u64), 2 * sizeof(u64));
| +
| + BUILD_BUG_ON(offsetof(struct thread_struct, tm_texasr)
| + + sizeof(u64) != offsetof(struct thread_struct, tm_tfiar));
| +
| + /* TFIAR register */
| + if (!ret)
| + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
| + &target->thread.tm_tfiar, 2 * sizeof(u64), 3 * sizeof(u64));
| +
| + BUILD_BUG_ON(offsetof(struct thread_struct, tm_tfiar)
| + + sizeof(u64) != offsetof(struct thread_struct, tm_orig_msr));
| +
| + /* TM checkpointed orig MSR */
| + if (!ret)
| + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
| + &target->thread.tm_orig_msr, 3 * sizeof(u64),
| + 3 * sizeof(u64) + sizeof(unsigned long));
| +
| + BUILD_BUG_ON(offsetof(struct thread_struct, tm_orig_msr)
| + + sizeof(unsigned long) + sizeof(struct pt_regs) !=
| + offsetof(struct thread_struct, tm_tar));
| +
| + /* TM checkpointed TAR register */
| + if (!ret)
| + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
| + &target->thread.tm_tar, 3 * sizeof(u64) +
| + sizeof(unsigned long), 3 * sizeof(u64) +
| + 2 * sizeof(unsigned long));
| +
| + BUILD_BUG_ON(offsetof(struct thread_struct, tm_tar)
| + + sizeof(unsigned long) != offsetof(struct thread_struct, tm_ppr));
| +
| + /* TM checkpointed PPR register */
| + if (!ret)
| + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
| + &target->thread.tm_ppr, 3 * sizeof(u64)
| + + 2 * sizeof(unsigned long), 3 * sizeof(u64)
| + + 3 * sizeof(unsigned long));
| +
| + BUILD_BUG_ON(offsetof(struct thread_struct, tm_ppr) +
| + sizeof(unsigned long) !=
| + offsetof(struct thread_struct, tm_dscr));
| +
| + /* TM checkpointed DSCR register */
| + if (!ret)
| + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
| + &target->thread.tm_dscr,
| + 3 * sizeof(u64) + 3 * sizeof(unsigned long),
| + 3 * sizeof(u64) + 4 * sizeof(unsigned long));
| +
| + return ret;
| +}
| +
| +static int tm_cgpr_active(struct task_struct *target,
| + const struct user_regset *regset)
| +{
| + if (!cpu_has_feature(CPU_FTR_TM))
| + return -ENODEV;
| +
| + if(!MSR_TM_ACTIVE(target->thread.regs->msr))
| + return 0;
| +
| + return regset->n;
| +}
| +
| +/*
| + * TM Checkpointed GPR
| + *
| + * struct data {
| + * struct pt_regs ckpt_regs;
| + * };
| + */
| +static int tm_cgpr_get(struct task_struct *target, const struct user_regset *regset,
| + unsigned int pos, unsigned int count,
| + void *kbuf, void __user *ubuf)
| +{
| + int ret;
| +
| + if (!cpu_has_feature(CPU_FTR_TM))
| + return -ENODEV;
| +
| + if(!MSR_TM_ACTIVE(target->thread.regs->msr))
| + return -ENODATA;
| +
| + flush_fp_to_thread(target);
| + flush_altivec_to_thread(target);
| + flush_tmregs_to_thread(target);
| + ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
| + &target->thread.ckpt_regs, 0,
| + sizeof(struct pt_regs));
| + return ret;
| +}
| +
| +static int tm_cgpr_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;
| +
| + if (!cpu_has_feature(CPU_FTR_TM))
| + return -ENODEV;
| +
| + if(!MSR_TM_ACTIVE(target->thread.regs->msr))
| + return -ENODATA;
| +
| + flush_fp_to_thread(target);
| + flush_altivec_to_thread(target);
| + flush_tmregs_to_thread(target);
| + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
| + &target->thread.ckpt_regs, 0,
| + sizeof(struct pt_regs));
| + return ret;
| +}
| +
| +static int tm_cfpr_active(struct task_struct *target,
| + const struct user_regset *regset)
| +{
| + if (!cpu_has_feature(CPU_FTR_TM))
| + return -ENODEV;
| +
| + if(!MSR_TM_ACTIVE(target->thread.regs->msr))
| + return 0;
| +
| + return regset->n;
| +}
| +
| +/*
| + * TM Checkpointed FPR
| + *
| + * struct data {
| + * u64 fpr[32];
| + * u64 fpscr;
| + * };
| + */
| +static int tm_cfpr_get(struct task_struct *target, const struct user_regset *regset,
| + unsigned int pos, unsigned int count,
| + void *kbuf, void __user *ubuf)
| +{
| +#ifdef CONFIG_VSX
| + u64 buf[33];
| + int i;
| +#endif
| + if (!cpu_has_feature(CPU_FTR_TM))
| + return -ENODEV;
| +
| + if(!MSR_TM_ACTIVE(target->thread.regs->msr))
| + return -ENODATA;
| +
| + flush_fp_to_thread(target);
| + flush_altivec_to_thread(target);
| + flush_tmregs_to_thread(target);
| +
| +#ifdef CONFIG_VSX
| + /* copy to local buffer then write that out */
| + for (i = 0; i < 32 ; i++)
| + buf[i] = target->thread.TS_FPR(i);
| + buf[32] = target->thread.fp_state.fpscr;
| + return user_regset_copyout(&pos, &count, &kbuf, &ubuf, buf, 0, -1);
| +
| +#else
| + BUILD_BUG_ON(offsetof(struct thread_fp_state, fpscr) !=
| + offsetof(struct thread_fp_state, fpr[32][0]));
| +
| + return user_regset_copyout(&pos, &count, &kbuf, &ubuf,
| + &target->thread.thread_fp_state, 0, -1);
| +#endif
| +}
| +
| +static int tm_cfpr_set(struct task_struct *target, const struct user_regset *regset,
| + unsigned int pos, unsigned int count,
| + const void *kbuf, const void __user *ubuf)
| +{
| +#ifdef CONFIG_VSX
| + u64 buf[33];
| + int i;
| +#endif
| + if (!cpu_has_feature(CPU_FTR_TM))
| + return -ENODEV;
| +
| + if(!MSR_TM_ACTIVE(target->thread.regs->msr))
| + return -ENODATA;
| +
| + flush_fp_to_thread(target);
| + flush_altivec_to_thread(target);
| + flush_tmregs_to_thread(target);
| +
| +#ifdef CONFIG_VSX
| + /* copy to local buffer then write that out */
| + i = user_regset_copyin(&pos, &count, &kbuf, &ubuf, buf, 0, -1);
| + if (i)
| + return i;
| + for (i = 0; i < 32 ; i++)
| + target->thread.TS_FPR(i) = buf[i];
| + target->thread.fp_state.fpscr = buf[32];
| + return 0;
| +#else
| + BUILD_BUG_ON(offsetof(struct thread_fp_state, fpscr) !=
| + offsetof(struct thread_fp_state, fpr[32][0]));
| +
| + return user_regset_copyin(&pos, &count, &kbuf, &ubuf,
| + &target->thread.fp_state, 0, -1);
| +#endif
| +}
| +
| +static int tm_cvmx_active(struct task_struct *target,
| + const struct user_regset *regset)
| +{
| + if (!cpu_has_feature(CPU_FTR_TM))
| + return -ENODEV;
| +
| + if(!MSR_TM_ACTIVE(target->thread.regs->msr))
| + return 0;
| +
| + return regset->n;
| +}

All these tm_*_active() functions do the same checks - maybe they could all
call a common function ?

| +
| +/*
| + * TM Checkpointed VMX
| + *
| + * struct data {
| + * vector128 vr[32];
| + * vector128 vscr;
| + * vector128 vrsave;
| + *};
| + */
| +static int tm_cvmx_get(struct task_struct *target, const struct user_regset *regset,
| + unsigned int pos, unsigned int count,
| + void *kbuf, void __user *ubuf)
| +{
| + int ret;
| +
| + if (!cpu_has_feature(CPU_FTR_TM))
| + return -ENODEV;
| +
| + if(!MSR_TM_ACTIVE(target->thread.regs->msr))
| + return -ENODATA;
| +
| + flush_fp_to_thread(target);
| + flush_altivec_to_thread(target);
| + flush_tmregs_to_thread(target);
| +
| + BUILD_BUG_ON(offsetof(struct thread_vr_state, vscr) !=
| + offsetof(struct thread_vr_state, vr[32]));
| +
| + ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
| + &target->thread.vr_state, 0,
| + 33 * sizeof(vector128));
| + if (!ret) {
| + /*
| + * Copy out only the low-order word of vrsave.
| + */
| + union {
| + elf_vrreg_t reg;
| + u32 word;
| + } vrsave;
| + memset(&vrsave, 0, sizeof(vrsave));
| + vrsave.word = target->thread.vrsave;
| + ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, &vrsave,
| + 33 * sizeof(vector128), -1);
| + }
| + return ret;
| +}
| +
| +static int tm_cvmx_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;
| +
| + if (!cpu_has_feature(CPU_FTR_TM))
| + return -ENODEV;
| +
| + if(!MSR_TM_ACTIVE(target->thread.regs->msr))
| + return -ENODATA;
| +
| + flush_fp_to_thread(target);
| + flush_altivec_to_thread(target);
| + flush_tmregs_to_thread(target);
| +
| + BUILD_BUG_ON(offsetof(struct thread_vr_state, vscr) !=
| + offsetof(struct thread_vr_state, vr[32]));
| +
| + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
| + &target->thread.vr_state, 0,
| + 33 * sizeof(vector128));
| + if (!ret && count > 0) {
| + /*
| + * We use only the first word of vrsave.
| + */
| + union {
| + elf_vrreg_t reg;
| + u32 word;
| + } vrsave;
| + memset(&vrsave, 0, sizeof(vrsave));
| + vrsave.word = target->thread.vrsave;
| + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &vrsave,
| + 33 * sizeof(vector128), -1);
| + if (!ret)
| + target->thread.vrsave = vrsave.word;
| + }
| + return ret;
| +}
| +#endif /* CONFIG_PPC_TRANSACTIONAL_MEM */
|
| /*
| * These are our native regset flavors.
| @@ -629,6 +1163,12 @@ enum powerpc_regset {
| #ifdef CONFIG_SPE
| REGSET_SPE,
| #endif
| +#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
| + REGSET_TM_SPR, /* TM specific SPR */
| + REGSET_TM_CGPR, /* TM checkpointed GPR */
| + REGSET_TM_CFPR, /* TM checkpointed FPR */
| + REGSET_TM_CVMX, /* TM checkpointed VMX */
| +#endif
| };
|
| static const struct user_regset native_regsets[] = {
| @@ -663,6 +1203,28 @@ static const struct user_regset native_regsets[] = {
| .active = evr_active, .get = evr_get, .set = evr_set
| },
| #endif
| +#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
| + [REGSET_TM_SPR] = {
| + .core_note_type = NT_PPC_TM_SPR, .n = 7,

How about adding a macro ELF_NSPRREG for the 7 special registers ?

| + .size = sizeof(u64), .align = sizeof(u64),
| + .active = tm_spr_active, .get = tm_spr_get, .set = tm_spr_set
| + },
| + [REGSET_TM_CGPR] = {
| + .core_note_type = NT_PPC_TM_CGPR, .n = ELF_NGREG,
| + .size = sizeof(long), .align = sizeof(long),
| + .active = tm_cgpr_active, .get = tm_cgpr_get, .set = tm_cgpr_set
| + },
| + [REGSET_TM_CFPR] = {
| + .core_note_type = NT_PPC_TM_CFPR, .n = ELF_NFPREG,
| + .size = sizeof(double), .align = sizeof(double),
| + .active = tm_cfpr_active, .get = tm_cfpr_get, .set = tm_cfpr_set
| + },
| + [REGSET_TM_CVMX] = {
| + .core_note_type = NT_PPC_TM_CVMX, .n = 34,

Similarly for the .n = 34

| + .size = sizeof(vector128), .align = sizeof(vector128),
| + .active = tm_cvmx_active, .get = tm_cvmx_get, .set = tm_cvmx_set
| + },
| +#endif
| };
|
| static const struct user_regset_view user_ppc_native_view = {
| @@ -690,7 +1252,7 @@ static int gpr32_get(struct task_struct *target,
| if (!FULL_REGS(target->thread.regs)) {
| /* We have a partial register set. Fill 14-31 with bogus values */
| for (i = 14; i < 32; i++)
| - target->thread.regs->gpr[i] = NV_REG_POISON;
| + target->thread.regs->gpr[i] = NV_REG_POISON;
| }
|
| pos /= sizeof(reg);
| @@ -803,6 +1365,157 @@ static int gpr32_set(struct task_struct *target,
| (PT_TRAP + 1) * sizeof(reg), -1);
| }
|
| +static int tm_cgpr32_get(struct task_struct *target,
| + const struct user_regset *regset,
| + unsigned int pos, unsigned int count,
| + void *kbuf, void __user *ubuf)
| +{
| + const unsigned long *regs = &target->thread.ckpt_regs.gpr[0];
| + compat_ulong_t *k = kbuf;
| + compat_ulong_t __user *u = ubuf;
| + compat_ulong_t reg;
| + int i;
| +
| + if (!cpu_has_feature(CPU_FTR_TM))
| + return -ENODEV;
| +
| + if(!MSR_TM_ACTIVE(target->thread.regs->msr))
| + return -ENODATA;
| +
| + flush_fp_to_thread(target);
| + flush_altivec_to_thread(target);
| + flush_tmregs_to_thread(target);
| +
| + if (target->thread.regs == NULL)
| + return -EIO;
| +
| + if (!FULL_REGS(target->thread.regs)) {
| + /* We have a partial register set. Fill 14-31 with bogus values */
| + for (i = 14; i < 32; i++)
| + target->thread.regs->gpr[i] = NV_REG_POISON;
| + }
| +
| + pos /= sizeof(reg);
| + count /= sizeof(reg);
| +
| + if (kbuf)
| + for (; count > 0 && pos < PT_MSR; --count)
| + *k++ = regs[pos++];
| + else
| + for (; count > 0 && pos < PT_MSR; --count)
| + if (__put_user((compat_ulong_t) regs[pos++], u++))
| + return -EFAULT;
| +
| + if (count > 0 && pos == PT_MSR) {
| + reg = get_user_msr(target);
| + if (kbuf)
| + *k++ = reg;
| + else if (__put_user(reg, u++))
| + return -EFAULT;
| + ++pos;
| + --count;
| + }
| +
| + if (kbuf)
| + for (; count > 0 && pos < PT_REGS_COUNT; --count)
| + *k++ = regs[pos++];
| + else
| + for (; count > 0 && pos < PT_REGS_COUNT; --count)
| + if (__put_user((compat_ulong_t) regs[pos++], u++))
| + return -EFAULT;
| +
| + kbuf = k;
| + ubuf = u;
| + pos *= sizeof(reg);
| + count *= sizeof(reg);
| + return user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
| + PT_REGS_COUNT * sizeof(reg), -1);
| +}
| +
| +static int tm_cgpr32_set(struct task_struct *target,
| + const struct user_regset *regset,
| + unsigned int pos, unsigned int count,
| + const void *kbuf, const void __user *ubuf)
| +{
| + unsigned long *regs = &target->thread.ckpt_regs.gpr[0];
| + const compat_ulong_t *k = kbuf;
| + const compat_ulong_t __user *u = ubuf;
| + compat_ulong_t reg;
| +
| + if (!cpu_has_feature(CPU_FTR_TM))
| + return -ENODEV;
| +
| + if(!MSR_TM_ACTIVE(target->thread.regs->msr))
| + return -ENODATA;
| +
| + flush_fp_to_thread(target);
| + flush_altivec_to_thread(target);
| + flush_tmregs_to_thread(target);
| +
| + if (target->thread.regs == NULL)
| + return -EIO;
| +
| + CHECK_FULL_REGS(target->thread.regs);
| +
| + pos /= sizeof(reg);
| + count /= sizeof(reg);
| +
| + if (kbuf)
| + for (; count > 0 && pos < PT_MSR; --count)
| + regs[pos++] = *k++;
| + else
| + for (; count > 0 && pos < PT_MSR; --count) {
| + if (__get_user(reg, u++))
| + return -EFAULT;
| + regs[pos++] = reg;
| + }
| +
| +
| + if (count > 0 && pos == PT_MSR) {
| + if (kbuf)
| + reg = *k++;
| + else if (__get_user(reg, u++))
| + return -EFAULT;
| + set_user_msr(target, reg);
| + ++pos;
| + --count;
| + }
| +
| + if (kbuf) {
| + for (; count > 0 && pos <= PT_MAX_PUT_REG; --count)
| + regs[pos++] = *k++;
| + for (; count > 0 && pos < PT_TRAP; --count, ++pos)
| + ++k;
| + } else {
| + for (; count > 0 && pos <= PT_MAX_PUT_REG; --count) {
| + if (__get_user(reg, u++))
| + return -EFAULT;
| + regs[pos++] = reg;
| + }
| + for (; count > 0 && pos < PT_TRAP; --count, ++pos)
| + if (__get_user(reg, u++))
| + return -EFAULT;
| + }
| +
| + if (count > 0 && pos == PT_TRAP) {
| + if (kbuf)
| + reg = *k++;
| + else if (__get_user(reg, u++))
| + return -EFAULT;
| + set_user_trap(target, reg);
| + ++pos;
| + --count;
| + }
| +
| + kbuf = k;
| + ubuf = u;
| + pos *= sizeof(reg);
| + count *= sizeof(reg);
| + return user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
| + (PT_TRAP + 1) * sizeof(reg), -1);
| +}
| +
| +
| /*
| * These are the regset flavors matching the CONFIG_PPC32 native set.
| */
| @@ -831,6 +1544,28 @@ static const struct user_regset compat_regsets[] = {
| .active = evr_active, .get = evr_get, .set = evr_set
| },
| #endif
| +#ifdef CONFIG_PPC_TRANSACTIONAL_MEM
| + [REGSET_TM_SPR] = {
| + .core_note_type = NT_PPC_TM_SPR, .n = 7,
| + .size = sizeof(u64), .align = sizeof(u64),
| + .active = tm_spr_active, .get = tm_spr_get, .set = tm_spr_set
| + },
| + [REGSET_TM_CGPR] = {
| + .core_note_type = NT_PPC_TM_CGPR, .n = ELF_NGREG,
| + .size = sizeof(long), .align = sizeof(long),
| + .active = tm_cgpr_active, .get = tm_cgpr32_get, .set = tm_cgpr32_set
| + },
| + [REGSET_TM_CFPR] = {
| + .core_note_type = NT_PPC_TM_CFPR, .n = ELF_NFPREG,
| + .size = sizeof(double), .align = sizeof(double),
| + .active = tm_cfpr_active, .get = tm_cfpr_get, .set = tm_cfpr_set
| + },
| + [REGSET_TM_CVMX] = {
| + .core_note_type = NT_PPC_TM_CVMX, .n = 34,
| + .size = sizeof(vector128), .align = sizeof(vector128),
| + .active = tm_cvmx_active, .get = tm_cvmx_get, .set = tm_cvmx_set
| + },
| +#endif
| };
|
| static const struct user_regset_view user_ppc_compat_view = {
| @@ -1754,7 +2489,6 @@ long arch_ptrace(struct task_struct *child, long request,
| REGSET_SPE, 0, 35 * sizeof(u32),
| datavp);
| #endif
| -
| default:
| ret = ptrace_request(child, request, addr, data);
| break;
| --
| 1.7.11.7
|
| _______________________________________________
| Linuxppc-dev mailing list
| Linuxppc-dev@xxxxxxxxxxxxxxxx
| https://lists.ozlabs.org/listinfo/linuxppc-dev

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