[CRIU] [PATCH 9/7] Added --mix-pre-dump option for zdtm suite
Radostin Stoyanov
rstoyanov1 at gmail.com
Thu Sep 5 06:45:00 MSK 2019
On 02/09/2019 07:19, abhishek dubey wrote:
> On 01/09/19 1:07 AM, Radostin Stoyanov wrote:
>>
>> On 31/08/2019 13:12, Abhishek Dubey wrote:
>>> READ and SPLICE mode pre-dumps can happen
>>> in any order. New option --mix-pre-dump is
>>> added for zdtm suite only, to test integrity
>>> of random order of pre-dump modes.
>> It is important when a test fails to be able to reproduce the error
>> consistently. The use of random order for testing might make
>> debugging difficult.
> Sure. I will remove random to preserve consistency.
>>
>>> Signed-off-by: Abhishek Dubey <dubeyabhishek777 at gmail.com>
>>> ---
>>> criu/cr-dump.c | 4 ++--
>>> criu/cr-restore.c | 4 ++--
>>> criu/include/stats.h | 4 ++--
>>> criu/mem.c | 65
>>> ++++++++++++++++++++++++++++++++++++++++------------
>>> criu/stats.c | 42 ++++++++++++++++++++++++++++++++-
>>> images/stats.proto | 1 +
>>> test/zdtm.py | 13 ++++++++++-
>>> 7 files changed, 110 insertions(+), 23 deletions(-)
>>>
>>> diff --git a/criu/cr-dump.c b/criu/cr-dump.c
>>> index b916e0a..f62362f 100644
>>> --- a/criu/cr-dump.c
>>> +++ b/criu/cr-dump.c
>>> @@ -1554,7 +1554,7 @@ err:
>>> if (ret)
>>> pr_err("Pre-dumping FAILED.\n");
>>> else {
>>> - write_stats(DUMP_STATS);
>>> + write_stats(DUMP_STATS, 1);
>>> pr_info("Pre-dumping finished successfully\n");
>>> }
>>> return ret;
>>> @@ -1760,7 +1760,7 @@ static int cr_dump_finish(int ret)
>>> if (ret) {
>>> pr_err("Dumping FAILED.\n");
>>> } else {
>>> - write_stats(DUMP_STATS);
>>> + write_stats(DUMP_STATS, 0);
>>> pr_info("Dumping finished successfully\n");
>>> }
>>> return post_dump_ret ? : (ret != 0);
>>> diff --git a/criu/cr-restore.c b/criu/cr-restore.c
>>> index de0b2cb..8ca46e4 100644
>>> --- a/criu/cr-restore.c
>>> +++ b/criu/cr-restore.c
>>> @@ -2226,7 +2226,7 @@ skip_ns_bouncing:
>>> if (ret != 0) {
>>> pr_err("Aborting restore due to post-restore script ret
>>> code %d\n", ret);
>>> timing_stop(TIME_RESTORE);
>>> - write_stats(RESTORE_STATS);
>>> + write_stats(RESTORE_STATS, 0);
>>> goto out_kill;
>>> }
>>> @@ -2292,7 +2292,7 @@ skip_ns_bouncing:
>>> /* Detaches from processes and they continue run through
>>> sigreturn. */
>>> finalize_restore_detach(ret);
>>> - write_stats(RESTORE_STATS);
>>> + write_stats(RESTORE_STATS, 0);
>>> ret = run_scripts(ACT_POST_RESUME);
>>> if (ret != 0)
>>> diff --git a/criu/include/stats.h b/criu/include/stats.h
>>> index 5d408b7..e6f86cb 100644
>>> --- a/criu/include/stats.h
>>> +++ b/criu/include/stats.h
>>> @@ -51,6 +51,6 @@ extern void cnt_sub(int c, unsigned long val);
>>> #define RESTORE_STATS 2
>>> extern int init_stats(int what);
>>> -extern void write_stats(int what);
>>> -
>>> +extern void write_stats(int what, int pre_dump);
>>> +extern int get_parent_pre_dump_type();
>>> #endif /* __CR_STATS_H__ */
>>> diff --git a/criu/mem.c b/criu/mem.c
>>> index 15094f7..0cfa4c2 100644
>>> --- a/criu/mem.c
>>> +++ b/criu/mem.c
>>> @@ -351,7 +351,8 @@ static int generate_vma_iovs(struct pstree_item
>>> *item, struct vma_area *vma,
>>> struct page_pipe *pp, struct page_xfer *xfer,
>>> struct parasite_dump_pages_args *args,
>>> struct parasite_ctl *ctl, pmc_t *pmc,
>>> - bool has_parent, bool pre_dump)
>>> + bool has_parent, bool pre_dump,
>>> + int parent_predump_mode)
>> Should the patch be applied after "[PATCH 2/7] Skip generating iov
>> for non PROT_READ region" ?
>>
>> diff --git a/criu/mem.c b/criu/mem.c
>> index e19688d..740992d 100644
>> --- a/criu/mem.c
>> +++ b/criu/mem.c
>> @@ -351,7 +351,7 @@ static int generate_vma_iovs(struct pstree_item
>> *item, struct vma_area *vma,
>> struct page_pipe *pp, struct page_xfer *xfer,
>> struct parasite_dump_pages_args *args,
>> struct parasite_ctl *ctl, pmc_t *pmc,
>> - bool has_parent, bool pre_dump)
>> + bool has_parent, struct mem_dump_ctl *mdc)
>>
>>
>>> {
>>> u64 off = 0;
>>> u64 *map;
>>> @@ -362,17 +363,47 @@ static int generate_vma_iovs(struct
>>> pstree_item *item, struct vma_area *vma,
>>> return 0;
>>> /*
>>> - * process_vm_readv syscall can't copy memory regions lacking
>>> - * PROT_READ flag. Therefore, avoid generating iovs for such
>>> - * regions in "read" mode pre-dump. Regions skipped by pre-dumps
>>> - * can't be referred as parent by following dump stage. So, mark
>>> - * "has_parent=false" for such regions.
>>> + * To facilitate any combination of pre-dump modes to run after
>>> + * one another, we need to take extra care as discussed below.
>>> + *
>>> + * The SPLICE mode pre-dump, processes all type of memory regions,
>>> + * whereas READ mode pre-dump skips processing those memory
>>> regions
>>> + * which lacks PROT_READ flag.
>>> + *
>>> + * Now on mixing pre-dump modes:
>>> + * If SPLICE mode follows SPLICE mode : no issue
>>> + * -> everything dumped both the times
>>> + *
>>> + * If READ mode follows READ mode : no issue
>>> + * -> non-PROT_READ skipped both the time
>>> + *
>>> + * If READ mode follows SPLICE mode : no issue
>>> + * -> everything dumped at first,
>>> + * the non-PROT_READ skipped later
>>> + *
>>> + * If SPLICE mode follows READ mode : Need special care
>>> + *
>> It would be good to cover these 4 cases with a test.
> Random order will be replaced by these 4 cases.
>>
>>> + * If READ pre-dump happens first then it has skipped processing
>>> + * non-PROT_READ regions. Following SPLICE pre-dump expects
>>> pagemap
>>> + * entries for all mappings in parent pagemap, but last READ mode
>>> + * pre-dump has skipped processing and pagemap generation for
>>> + * non-PROT_READ regions. So SPLICE mode throws error of missing
>>> + * pagemap entry for non-PROT_READ mapping.
>>> + *
>>> + * To resolve this, the mode of pre-dump is stored in pre-dump's
>>> + * stats file. This mode is read back from stats file during next
>>> + * pre-dump.
>> The purpose of the stats file is to contain statistics about how
>> dump/restore went. IMHO the data in this file should not be required
>> for pre-dump.
>
> If we don't mix splice and read modes, then we can completely avoid
> this whole stat-file writing/reading. But, if we mix pre-dump-modes in
> single run then we need
>
> to tell splice-pre-dump, about what has been skipped in parent images
> through read-pre-dumps.
>
I understand that we need to include information about what pre-dump
mode was used but I think that stats-dump is not the right image for this.
Can we use inventory.img instead?
Radostin
More information about the CRIU
mailing list