On 2018年07月16日 16:14, Su Yue wrote:
>
>
> On 07/16/2018 03:45 PM, Qu Wenruo wrote:
>>
>>
>> On 2018年07月16日 13:55, Su Yue wrote:
>>> For big filesystems, there are many items in trees(extent tree
>>> specially).
>>> For example, to dump one extent, we usually dump extent tree then pipe
>>> result to grep. The time-consuming part is that dump tree traverses
>>> items. And it eats cpu and memory too.
>>>
>>> This patch introduces an option '-k u64,u8,u64' for users(developer more
>>> likely) to appoint a specific key to search and dump, then the path
>>> from root node down the leaf will be dumped.
>>> The search of the key costs most time of this way.
>>
>> Indeed a pretty useful debug oriented feature.
>>
>>>
>>> Signed-off-by: Su Yue <suy.f...@cn.fujitsu.com>
>>> ---
>>> In my experiment, not usual case though.
>>> Image was provided by Chris Murphy, thanks.
>>>
>>> #btrfs filesystem df /mnt
>>> Data, single: total=767.00GiB, used=766.58GiB
>>> System, DUP: total=32.00MiB, used=112.00KiB
>>> Metadata, DUP: total=5.50GiB, used=4.69GiB
>>> Metadata, single: total=16.00MiB, used=0.00B
>>> GlobalReserve, single: total=512.00MiB, used=0.00B
>>>
>>> Before:
>>> #time bash -c 'btrfs inspect-internal dump-tree -t 2 ~/test/test.img
>>> | grep "1295194308608" >> /dev/null'
>>> real 0m34.024s
>>> user 0m3.269s
>>> sys 0m4.047s
>>>
>>> Patched and use -k:
>>> #time bash -c './btrfs inspect-internal dump-tree -t 2 -k
>>> 1295194308608,0,0 ~/test/test.img >> /dev/null'
>>>
>>> real 0m1.408s
>>> user 0m0.006s
>>> sys 0m0.014s
>>>
>>> The new way is 34 times faster than 'grep' way, uses less memory and
>>> cpu, and it prints path useful for debug.
>>>
>>> ---
>>> cmds-inspect-dump-tree.c | 54 +++++++++++++++++--
>>> print-tree.c | 112 +++++++++++++++++++++++++++++++++++++++
>>> print-tree.h | 2 +
>>> 3 files changed, 163 insertions(+), 5 deletions(-)
>>>
>>> diff --git a/cmds-inspect-dump-tree.c b/cmds-inspect-dump-tree.c
>>> index c8acd55a0c3a..2a1a40c8270d 100644
>>> --- a/cmds-inspect-dump-tree.c
>>> +++ b/cmds-inspect-dump-tree.c
>>> @@ -184,6 +184,21 @@ static u64 treeid_from_string(const char *str,
>>> const char **end)
>>> return id;
>>> }
>>> +static int parse_key(struct btrfs_key *key)
>>> +{
>>> +
>>> + int ret = sscanf(optarg, "%llu,%hhu,%llu", &key->objectid,
>>> + &key->type, &key->offset);
>>> + if (ret != 3) {
>>> + error("error parsing key '%s'\n", optarg);
>>> + ret = -EINVAL;
>>> + } else {
>>> + ret = 0;
>>> + }
>>> +
>>> + return ret;
>>> +}
>>> +
>>> const char * const cmd_inspect_dump_tree_usage[] = {
>>> "btrfs inspect-internal dump-tree [options] device",
>>> "Dump tree structures from a given device",
>>> @@ -199,6 +214,7 @@ const char * const cmd_inspect_dump_tree_usage[] = {
>>> "-u|--uuid print only the uuid tree",
>>> "-b|--block <block_num> print info from the specified block only",
>>> "-t|--tree <tree_id> print only tree with the given id
>>> (string or number)",
>>> + "-k|--key <u64,u8,u64> search the specific key then print path,
>>> must with -t",
>>
>> Shouldn't it conflict with -b and -r?
>>
>>> "--follow use with -b, to show all children tree
>>> blocks of <block_num>",
>>> NULL
>>> };
>>> @@ -224,8 +240,10 @@ int cmd_inspect_dump_tree(int argc, char **argv)
>>> unsigned open_ctree_flags;
>>> u64 block_only = 0;
>>> struct btrfs_root *tree_root_scan;
>>> + struct btrfs_key spec_key = { 0 };
>>> u64 tree_id = 0;
>>> bool follow = false;
>>> + bool is_key_spec = false;
>>
>> What about @key_set? @is_key_spec looks a little strange here.
>>
> Ok, will call it is_spec_key_set in next version.
>
>>> /*
>>> * For debug-tree, we care nothing about extent tree (it's just
>>> backref
>>> @@ -248,10 +266,11 @@ int cmd_inspect_dump_tree(int argc, char **argv)
>>> { "block", required_argument, NULL, 'b'},
>>> { "tree", required_argument, NULL, 't'},
>>> { "follow", no_argument, NULL, GETOPT_VAL_FOLLOW },
>>> + {"key", required_argument, NULL, 'k'},
>>
>> Small alignment mismatch, missing a space before "key".
>>
>>> { NULL, 0, NULL, 0 }
>>> };
>>> - c = getopt_long(argc, argv, "deb:rRut:", long_options, NULL);
>>> + c = getopt_long(argc, argv, "deb:rRut:k:", long_options, NULL);
>>> if (c < 0)
>>> break;
>>> switch (c) {
>>> @@ -300,6 +319,12 @@ int cmd_inspect_dump_tree(int argc, char **argv)
>>> }
>>> break;
>>> }
>>> + case 'k':
>>> + ret = parse_key(&spec_key);
>>> + if (ret)
>>> + exit(1);
>>> + is_key_spec = true;
>>> + break;
>>> case GETOPT_VAL_FOLLOW:
>>> follow = true;
>>> break;
>>> @@ -308,6 +333,9 @@ int cmd_inspect_dump_tree(int argc, char **argv)
>>> }
>>> }
>>> + if (!tree_id && is_key_spec)
>>> + usage(cmd_inspect_dump_tree_usage);
>>> +
>>> if (check_argc_exact(argc - optind, 1))
>>> usage(cmd_inspect_dump_tree_usage);
>>> @@ -398,7 +426,11 @@ again:
>>> goto close_root;
>>> }
>>> printf("root tree\n");
>>> - btrfs_print_tree(info->tree_root->node, 1);
>>> + if (is_key_spec)
>>> + btrfs_print_spec_key(info, BTRFS_ROOT_TREE_OBJECTID,
>>> + &spec_key);
>>> + else
>>> + btrfs_print_tree(info->tree_root->node, 1);
>>> goto close_root;
>>> }
>>> @@ -408,7 +440,11 @@ again:
>>> goto close_root;
>>> }
>>> printf("chunk tree\n");
>>> - btrfs_print_tree(info->chunk_root->node, 1);
>>> + if (is_key_spec)
>>> + btrfs_print_spec_key(info, BTRFS_CHUNK_TREE_OBJECTID,
>>> + &spec_key);
>>> + else
>>> + btrfs_print_tree(info->chunk_root->node, 1);
>>> goto close_root;
>>> }
>>>
>>
>> I really don't thing we need to put btrfS_print_spec_key() here.
>>
>> It's in fact a special case, no need to nest it into the loop.
>> Not to mention it appears 3 times in the main loop.
>>
> Not understood what you mean.
I mean, just put the function call of btrfs_print_spec_key() just after
open_ctree_fs_info().
So it should looks like:
info = open_ctree_fs_info();
if (!info){
/* error handling */
}
if (is_spec_key_set) {
ret = btrfs_print_spec_key(info, tree_id, &spec_key);
if (ret < 0) {
/* Error handling */
}
goto close_root;
}
...
Thanks,
Qu
>
>>> @@ -418,7 +454,11 @@ again:
>>> goto close_root;
>>> }
>>> printf("log root tree\n");
>>> - btrfs_print_tree(info->log_root_tree->node, 1);
>>> + if (is_key_spec)
>>> + btrfs_print_spec_key(info, BTRFS_TREE_LOG_OBJECTID,
>>> + &spec_key);
>>> + else
>>> + btrfs_print_tree(info->log_root_tree->node, 1);
>>> goto close_root;
>>> }
>>> @@ -564,7 +604,11 @@ again:
>>> btrfs_header_level(buf));
>>> } else {
>>> printf(" \n");
>>> - btrfs_print_tree(buf, 1);
>>> + if (is_key_spec)
>>> + btrfs_print_spec_key(info,
>>> + found_key.objectid, &spec_key);
>>> + else
>>> + btrfs_print_tree(buf, 1);
>>> }
>>> }
>>> free_extent_buffer(buf);
>>> diff --git a/print-tree.c b/print-tree.c
>>> index a09ecfbb28f0..f3a19fed8591 100644
>>> --- a/print-tree.c
>>> +++ b/print-tree.c
>>> @@ -1459,3 +1459,115 @@ void btrfs_print_tree(struct extent_buffer
>>> *eb, int follow)
>>> return;
>>> }
>>> +
>>> +void btrfs_print_spec_key(struct btrfs_fs_info *fs_info, u64
>>> root_objectid,
>>> + struct btrfs_key *skey)
>>> +{
>>> + int i;
>>> + u32 nr;
>>> + u32 ptr_num;
>>> + int ret;
>>> + int level;
>>> + struct btrfs_root *root;
>>> + struct btrfs_disk_key disk_key;
>>> + struct btrfs_key key;
>>> + struct extent_buffer *next;
>>> + struct extent_buffer *eb;
>>> + struct btrfs_path path;
>>> +
>>> + key.objectid = root_objectid;
>>> + key.type = BTRFS_ROOT_ITEM_KEY;
>>> + key.offset = (u64)-1;
>>> +
>>> + if (key.objectid == BTRFS_TREE_RELOC_OBJECTID)
>>> + root = btrfs_read_fs_root_no_cache(fs_info, &key);
>>> + else
>>> + root = btrfs_read_fs_root(fs_info, &key);
>>> +
>>> + if (IS_ERR(root) || !root) {
>>> + error("failed to read tree: %lld", key.objectid);
>>> + return;
>>> + }
>>> +
>>> + btrfs_init_path(&path);
>>> + ret = btrfs_search_slot(NULL, root, skey, &path, 0, 0);
>>> + if (ret < 0) {
>>> + error("error search the key [%llu, %u, %llu] in root %llu",
>>> + skey->objectid, skey->type, skey->offset,
>>> root->objectid);
>>> + goto out;
>>> + }
>>> +
>>> + if (ret > 0) {
>>> + if (path.slots[0] > btrfs_header_nritems(path.nodes[0])) {
>>> + ret = btrfs_next_item(root, &path);
>>> + if (ret) {
>>> + error(
>>> + "error search the key [%llu, %u, %llu] in root %llu, no next key",
>>> + skey->objectid, skey->type,
>>> + skey->offset, root->objectid);
>>> + goto out;
>>> + }
>>> + }
>>> +
>>> + btrfs_item_key_to_cpu(path.nodes[0], &key, path.slots[0]);
>>> + printf("next to search key is [%llu, %u, %llu]\n",
>>> + key.objectid, key.type, key.offset);
>>> + }
>>> +
>>> + level = btrfs_header_level(root->node);
>>> + for (; level >= 0 ; --level) {
>>> + eb = path.nodes[level];
>>> + next = path.nodes[level - 1];
>>> + nr = btrfs_header_nritems(eb);
>>
>> In fact, btrfs_print_tree() could replace all the following code.
>> Which should further shrink the code size.
>>
> Oh..just saw it, the code is copied and pasted from it though.
>
> Thanks,
> Su
>> Thanks,
>> Qu
>>
>>> + if (btrfs_is_leaf(eb)) {
>>> + btrfs_print_leaf(eb);
>>> + goto out;
>>> + }
>>> +
>>> + /* We are crossing eb boundary, this node must be corrupted */
>>> + if (nr > BTRFS_NODEPTRS_PER_EXTENT_BUFFER(eb))
>>> + warning(
>>> + "node nr_items corrupted, has %u limit %u, continue anyway",
>>> + nr, BTRFS_NODEPTRS_PER_EXTENT_BUFFER(eb));
>>> + printf(
>>> + "node %llu level %d items %d free %u generation %llu owner ",
>>> + (unsigned long long)eb->start,
>>> + btrfs_header_level(eb), nr,
>>> + (u32)BTRFS_NODEPTRS_PER_EXTENT_BUFFER(eb) - nr,
>>> + (unsigned long long)btrfs_header_generation(eb));
>>> + print_objectid(stdout, btrfs_header_owner(eb), 0);
>>> + printf("\n");
>>> + print_uuids(eb);
>>> + fflush(stdout);
>>> + ptr_num = BTRFS_NODEPTRS_PER_EXTENT_BUFFER(eb);
>>> + for (i = 0; i < nr && i < ptr_num; i++) {
>>> + u64 blocknr = btrfs_node_blockptr(eb, i);
>>> +
>>> + btrfs_node_key(eb, &disk_key, i);
>>> + btrfs_disk_key_to_cpu(&key, &disk_key);
>>> + printf("\t");
>>> + btrfs_print_key(&disk_key);
>>> + printf(" block %llu (%llu) gen %llu\n",
>>> + (unsigned long long)blocknr,
>>> + (unsigned long long)blocknr / eb->len,
>>> + (unsigned long long)btrfs_node_ptr_generation(eb,
>>> i));
>>> + fflush(stdout);
>>> + }
>>> +
>>> + if (btrfs_header_level(next) != btrfs_header_level(eb) - 1) {
>>> + warning(
>>> + "eb corrupted: parent bytenr %llu slot %d level %d
>>> child bytenr %llu level has %d expect %d, skipping the slot",
>>> + btrfs_header_bytenr(eb), i,
>>> + btrfs_header_level(eb),
>>> + btrfs_header_bytenr(next),
>>> + btrfs_header_level(next),
>>> + btrfs_header_level(eb) - 1);
>>> + continue;
>>> + }
>>> + }
>>> +
>>> +out:
>>> + if (root_objectid == BTRFS_TREE_RELOC_OBJECTID)
>>> + btrfs_free_fs_root(root);
>>> + btrfs_release_path(&path);
>>> +}
>>> diff --git a/print-tree.h b/print-tree.h
>>> index 62667d7f6195..94f231875a6c 100644
>>> --- a/print-tree.h
>>> +++ b/print-tree.h
>>> @@ -26,4 +26,6 @@ void print_chunk_item(struct extent_buffer *eb,
>>> struct btrfs_chunk *chunk);
>>> void print_extent_item(struct extent_buffer *eb, int slot, int
>>> metadata);
>>> void print_objectid(FILE *stream, u64 objectid, u8 type);
>>> void print_key_type(FILE *stream, u64 objectid, u8 type);
>>> +void btrfs_print_spec_key(struct btrfs_fs_info *info, u64
>>> root_objectid,
>>> + struct btrfs_key *key);
>>> #endif
>>>
>>
>>
>
>
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