Quoting Christoffer Dall ([email protected]): > Implements architecture specific requirements for checkpoint/restart on > ARM. The changes touch almost only c/r related code. Most of the work is > done in arch/arm/checkpoint.c, which implements checkpointing of the CPU > and necessary fields on the thread_info struct. > > The ISA version (given by __LINUX_ARM_ARCH__) is checkpointed and verified > against the machine architecture on restart. If they differ, an error is > raised and restart aborted. It should be possible to restart on newer > architectures, but further investigation is warranted. > > Regarding ThumbEE, the thumbee_state field on the thread_info is stored > in checkpoints when CONFIG_ARM_THUMBEE and 0 is stored otherwise. If > a value different than 0 is checkpointed and CONFIG_ARM_THUMBEE is not > set on the restore system, the restore is aborted. Feedback on this > implementation is very welcome. > > We checkpoint whether the system is running with CONFIG_MMU or not and > require the same configuration for the system on which we restore the > process. It might be possible to allow something more fine-grained, > if it's worth the energy. Input on this item is also very welcome, > specifically from someone who knows the exact meaning of the end_brk > field. > > Added support for syscall sys_checkpoint and sys_restart for ARM: > __NR_checkpoint 367 > __NR_restart 368 > > > Cc: [email protected] > Signed-off-by: Christoffer Dall <[email protected]> > Acked-by: Oren Laadan <[email protected]>
In terms of the cr api I don't see any problems. Two nits below, but in any case Acked-by: Serge Hallyn <[email protected]> thanks, this is really cool, especially how minimal it is :) -serge ... > +static int load_cpu_regs(struct ckpt_hdr_cpu *h, struct task_struct *t) > +{ > + int i; > + struct pt_regs *regs = task_pt_regs(t); > + > + memcpy(regs, &h->uregs, sizeof(struct pt_regs)); > + > + for (i = 0; i < 16; i++) > + regs->uregs[i] = h->uregs[i]; > + > + /* > + * Restore only user-writable bits on the CPSR > + */ > + regs->ARM_cpsr = regs->ARM_cpsr | > + (h->ARM_cpsr & (PSR_N_BIT | PSR_Z_BIT | > + PSR_C_BIT | PSR_V_BIT | > + PSR_V_BIT | PSR_Q_BIT | > + PSR_E_BIT | PSR_GE_BITS)); > + regs->ARM_ORIG_r0 = h->ARM_ORIG_r0; > + > + return 0; > +} > + > +/* read the cpu state and registers for the current task */ > +int restore_cpu(struct ckpt_ctx *ctx) > +{ > + struct ckpt_hdr_cpu *h; > + struct task_struct *t = current; > + int ret; > + > + h = ckpt_read_obj_type(ctx, sizeof(*h), CKPT_HDR_CPU); > + if (IS_ERR(h)) > + return PTR_ERR(h); > + > + ret = load_cpu_regs(h, t); will load_cpu_regs() ever be changed to return anything but 0? If not both fns can be simplified. ... > +int restore_mm_context(struct ckpt_ctx *ctx, struct mm_struct *mm) > +{ > + struct ckpt_hdr_mm_context *h; > + int ret = 0; > + > + h = ckpt_read_obj_type(ctx, sizeof(*h), CKPT_HDR_MM_CONTEXT); > + if (IS_ERR(h)) > + return PTR_ERR(h); > + > +#if !CONFIG_MMU > + mm->context.end_brk = h->end_brk; > +#endif > + > + ckpt_hdr_put(ctx, h); > + return ret; Again ret doesn't seem needed here. -serge _______________________________________________ Containers mailing list [email protected] https://lists.linux-foundation.org/mailman/listinfo/containers _______________________________________________ Devel mailing list [email protected] https://openvz.org/mailman/listinfo/devel
