[CRIU] [PATCH 7/7] dump: dump signals into core->thread_core->signals

[Ruslan Kuprieiev]

15.08.2014 14:52, Pavel Emelyanov пишет:
> On 08/14/2014 06:33 AM, Ruslan Kuprieiev wrote:
>> Every thread has it's own private signals and leader thread has also shared
>> signals.
> This patch lacks the hunk that moves CR_FD_SIGNAL from inside _CR_FD_TASK_XXX
> into outside, so that empty signals files are not even created.

Oh, good point.
Thanks.

>> Signed-off-by: Ruslan Kuprieiev <kupruser at gmail.com>
>> ---
>>   cr-dump.c | 81 ++++++++++++++++++++++++++++++++++++---------------------------
>>   1 file changed, 46 insertions(+), 35 deletions(-)
>>
>> diff --git a/cr-dump.c b/cr-dump.c
>> index 74a8b4c..a3a0aa9 100644
>> --- a/cr-dump.c
>> +++ b/cr-dump.c
>> @@ -1168,11 +1168,12 @@ err:
>>   	return ret;
>>   }
>>   
>> -static int dump_signal_queue(pid_t tid, int fd, bool group)
>> +static int dump_signal_queue(pid_t tid, SignalQueueEntry **sqe, bool group)
>>   {
>>   	struct ptrace_peeksiginfo_args arg;
>>   	siginfo_t siginfo[32]; /* One page or all non-rt signals */
>>   	int ret, i = 0, j, nr;
>> +	SignalQueueEntry *queue = NULL;
>>   
>>   	pr_debug("Dump %s signals of %d\n", group ? "shared" : "private", tid);
>>   
>> @@ -1181,6 +1182,12 @@ static int dump_signal_queue(pid_t tid, int fd, bool group)
>>   	if (group)
>>   		arg.flags |= PTRACE_PEEKSIGINFO_SHARED;
>>   
>> +	queue = xmalloc(sizeof(*queue));
>> +	if (!queue)
>> +		return -1;
>> +
>> +	signal_queue_entry__init(queue);
>> +
>>   	for (; ; ) {
>>   		arg.off = i;
>>   
>> @@ -1198,50 +1205,54 @@ static int dump_signal_queue(pid_t tid, int fd, bool group)
>>   			break;
>>   		nr = ret;
>>   
>> -		for (j = 0; j < nr; j++) {
>> -			SiginfoEntry sie = SIGINFO_ENTRY__INIT;
>> +		queue->n_signals += nr;
>> +		queue->signals = xrealloc(queue->signals, sizeof(*queue->signals) * queue->n_signals);
>> +		if (!queue->signals) {
>> +			ret = -1;
>> +			break;
>> +		}
>>   
>> -			sie.siginfo.len = sizeof(siginfo_t);
>> -			sie.siginfo.data = (void *) (siginfo + j);
>> +		for (j = queue->n_signals - nr; j < queue->n_signals; j++) {
>> +			queue->signals[j]->siginfo.len = sizeof(siginfo_t);
>> +			queue->signals[j]->siginfo.data = (void *) (siginfo + j);
>>   
>> -			ret = pb_write_one(fd, &sie, PB_SIGINFO);
>> -			if (ret < 0)
>> -				break;
>>   			i++;
>>   		}
>>   	}
>>   
>> +	*sqe = queue;
>> +
>>   	return ret;
>>   }
>>   
>> -static int dump_thread_signals(struct pid *tid)
>> +static int dump_task_signals(pid_t pid, struct pstree_item *item)
>>   {
>> -	int fd, ret;
>> +	int i, ret;
>> +	SignalsEntry *signals = NULL;
>>   
>> -	fd = open_image(CR_FD_PSIGNAL, O_DUMP, tid->virt);
>> -	if (fd < 0)
>> -		return -1;
>> -	ret = dump_signal_queue(tid->real, fd, false);
>> -	close(fd);
>> +	/* Dump private signals for each thread */
>> +	for (i = 0; i < item->nr_threads; i++) {
>> +		signals = xmalloc(sizeof(*signals));
>> +		if (!signals)
>> +			return -1;
>>   
>> -	return ret;
>> -}
>> +		signals_entry__init(signals);
>>   
>> -static int dump_task_signals(pid_t pid, struct pstree_item *item,
>> -		struct cr_fdset *cr_fdset)
>> -{
>> -	int i, ret;
>> +		ret = dump_signal_queue(item->threads[i].real, &signals->p, false);
>> +		if (ret) {
>> +			pr_err("Can't dump private signals for thread %d\n", item->threads[i].real);
>> +			return -1;
>> +		}
>>   
>> -	ret = dump_signal_queue(pid, fdset_fd(cr_fdset, CR_FD_SIGNAL), true);
>> -	if (ret) {
>> -		pr_err("Can't dump pending signals (pid: %d)\n", pid);
>> -		return -1;
>> +		item->core[i]->thread_core->signals = signals;
>>   	}
>>   
>> -	for (i = 0; i < item->nr_threads; i++) {
>> -		ret = dump_thread_signals(&item->threads[i]);
>> -		if (ret)
>> -			return -1;
>> +	/* Dump shared signals */
>> +	signals = item->core[0]->thread_core->signals;
>> +	ret = dump_signal_queue(pid, &signals->s, true);
>> +	if (ret) {
>> +		pr_err("Can't dump shared signals (pid: %d)\n", pid);
>> +		return -1;
>>   	}
>>   
>>   	return 0;
>> @@ -1501,6 +1512,12 @@ static int dump_one_task(struct pstree_item *item)
>>   		goto err;
>>   	}
>>   
>> +	ret = dump_task_signals(pid, item);
>> +	if (ret) {
>> +		pr_err("Dump %d signals failed %d\n", pid, ret);
>> +		goto err;
>> +	}
>> +
>>   	ret = -1;
>>   	parasite_ctl = parasite_infect_seized(pid, item, &vmas, dfds, proc_args.timer_n);
>>   	if (!parasite_ctl) {
>> @@ -1635,12 +1652,6 @@ static int dump_one_task(struct pstree_item *item)
>>   		goto err;
>>   	}
>>   
>> -	ret = dump_task_signals(pid, item, cr_fdset);
>> -	if (ret) {
>> -		pr_err("Dump %d signals failed %d\n", pid, ret);
>> -		goto err;
>> -	}
>> -
>>   	close_cr_fdset(&cr_fdset);
>>   err:
>>   	close_pid_proc();
>>