Dave Hansen wrote: > Oren, > > Could you take a look over Cedric's external checkpoint patch? > > http://git.kernel.org/?p=linux/kernel/git/daveh/linux-2.6-cr.git;a=commit;h=28ffabbc17d3641eee2a7eb66f714c266c400263 > > It seems pretty small to me. > > -- > >>From a2f88cbc023e2e9be5eb554fe64078a3d7d2ade6 Mon Sep 17 00:00:00 2001 > From: Cedric Le Goater <clg@xxxxxxxxxx> > Date: Tue, 30 Sep 2008 10:45:13 +0200 > Subject: [PATCH] enable external checkpoint > > Modify self checkpoint syscall to allow another process to initiate > checkpoint > > Signed-off-by: Cedric Le Goater <clg@xxxxxxxxxx> > --- > arch/x86/mm/checkpoint.c | 2 +- > checkpoint/checkpoint.c | 2 +- > checkpoint/sys.c | 28 +++++++++++++++++++++------- > include/linux/checkpoint.h | 1 + > 4 files changed, 24 insertions(+), 9 deletions(-) > > diff --git a/arch/x86/mm/checkpoint.c b/arch/x86/mm/checkpoint.c > index d6c5263..202a579 100644 > --- a/arch/x86/mm/checkpoint.c > +++ b/arch/x86/mm/checkpoint.c > @@ -164,7 +164,7 @@ void cr_write_cpu_fpu(struct cr_hdr_cpu *hh, struct task_struct *t) > * except if we are in process context, in which case we do > */ > if (thread_info->status & TS_USEDFPU) > - unlazy_fpu(current); > + unlazy_fpu(t); This is not needed (only needed in self checkpoint). > > hh->has_fxsr = cpu_has_fxsr; > memcpy(&hh->xstate, &thread->xstate, sizeof(thread->xstate)); > diff --git a/checkpoint/checkpoint.c b/checkpoint/checkpoint.c > index 87420dc..c4e8242 100644 > --- a/checkpoint/checkpoint.c > +++ b/checkpoint/checkpoint.c > @@ -227,7 +227,7 @@ int do_checkpoint(struct cr_ctx *ctx) > ret = cr_write_head(ctx); > if (ret < 0) > goto out; > - ret = cr_write_task(ctx, current); > + ret = cr_write_task(ctx, ctx->task); > if (ret < 0) > goto out; > ret = cr_write_tail(ctx); > diff --git a/checkpoint/sys.c b/checkpoint/sys.c > index 4fcd3e0..ec028c6 100644 > --- a/checkpoint/sys.c > +++ b/checkpoint/sys.c > @@ -176,7 +176,8 @@ void cr_ctx_free(struct cr_ctx *ctx) > kfree(ctx); > } > > -struct cr_ctx *cr_ctx_alloc(pid_t pid, int fd, unsigned long flags) > +struct cr_ctx *cr_ctx_alloc(struct task_struct *t, pid_t pid, int fd, > + unsigned long flags) > { > struct cr_ctx *ctx; > > @@ -184,6 +185,7 @@ struct cr_ctx *cr_ctx_alloc(pid_t pid, int fd, unsigned long flags) > if (!ctx) > return ERR_PTR(-ENOMEM); > > + ctx->task = t; > ctx->file = fget(fd); > if (!ctx->file) { > cr_ctx_free(ctx); > @@ -205,7 +207,7 @@ struct cr_ctx *cr_ctx_alloc(pid_t pid, int fd, unsigned long flags) > * assume checkpointer is in container's root vfs > * FIXME: this works for now, but will change with real containers > */ > - ctx->vfsroot = ¤t->fs->root; > + ctx->vfsroot = &t->fs->root; > path_get(ctx->vfsroot); > > INIT_LIST_HEAD(&ctx->pgarr_list); > @@ -231,20 +233,32 @@ asmlinkage long sys_checkpoint(pid_t pid, int fd, unsigned long flags) > { > struct cr_ctx *ctx; > int ret; > + struct task_struct *t; > > /* no flags for now */ > if (flags) > return -EINVAL; > > - ctx = cr_ctx_alloc(pid, fd, flags | CR_CTX_CKPT); > - if (IS_ERR(ctx)) > - return PTR_ERR(ctx); > + read_lock(&tasklist_lock); > + t = find_task_by_vpid(pid); > + if (t) > + get_task_struct(t); > + read_unlock(&tasklist_lock); missing put_task_struct() ? missing security check ? > + > + if (!t) > + return -ESRCH; > > + ctx = cr_ctx_alloc(t, pid, fd, flags | CR_CTX_CKPT); > + if (IS_ERR(ctx)) { > + ret = PTR_ERR(ctx); > + goto out; > + } > + > ret = do_checkpoint(ctx); > > if (!ret) > ret = ctx->crid; > - > +out: > cr_ctx_free(ctx); > return ret; > } > @@ -267,7 +281,7 @@ asmlinkage long sys_restart(int crid, int fd, unsigned long flags) > if (flags) > return -EINVAL; > > - ctx = cr_ctx_alloc(crid, fd, flags | CR_CTX_RSTR); > + ctx = cr_ctx_alloc(current, crid, fd, flags | CR_CTX_RSTR); > if (IS_ERR(ctx)) > return PTR_ERR(ctx); > > diff --git a/include/linux/checkpoint.h b/include/linux/checkpoint.h > index 6c1e87f..2983700 100644 > --- a/include/linux/checkpoint.h > +++ b/include/linux/checkpoint.h > @@ -17,6 +17,7 @@ > > struct cr_ctx { > pid_t pid; /* container identifier */ > + struct task_struct *task; > int crid; /* unique checkpoint id */ > > unsigned long flags; _______________________________________________ Containers mailing list Containers@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/containers
