Hi Kim,
On 03/10/2014 12:45 PM, Jaegeuk Kim wrote:
> Hi Gu,
>
> 2014-03-07 (금), 18:43 +0800, Gu Zheng:
>> Previously, we ra_sum_pages to pre-read contiguous pages as more
>> as possible, and if we fail to alloc more pages, an ENOMEM error
>> will be reported upstream, even though we have alloced some pages
>> yet. In fact, we can use the available pages to do the job partly,
>> and continue the rest in the following circle. Only reporting ENOMEM
>> upstream if we really can not alloc any available page.
>>
>> And another fix is ignoring dealing with the following pages if an
>> EIO occurs when reading page from page_list.
>>
>> Signed-off-by: Gu Zheng <guz.f...@cn.fujitsu.com>
>> ---
>> fs/f2fs/node.c | 44 ++++++++++++++++++++------------------------
>> fs/f2fs/segment.c | 7 +++++--
>> 2 files changed, 25 insertions(+), 26 deletions(-)
>>
>> diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
>> index 8787469..4b7861d 100644
>> --- a/fs/f2fs/node.c
>> +++ b/fs/f2fs/node.c
>> @@ -1588,15 +1588,8 @@ static int ra_sum_pages(struct f2fs_sb_info *sbi,
>> struct list_head *pages,
>> for (; page_idx < start + nrpages; page_idx++) {
>> /* alloc temporal page for read node summary info*/
>> page = alloc_page(GFP_F2FS_ZERO);
>> - if (!page) {
>> - struct page *tmp;
>> - list_for_each_entry_safe(page, tmp, pages, lru) {
>> - list_del(&page->lru);
>> - unlock_page(page);
>> - __free_pages(page, 0);
>> - }
>> - return -ENOMEM;
>> - }
>> + if (!page)
>> + break;
>>
>> lock_page(page);
>> page->index = page_idx;
>> @@ -1607,7 +1600,8 @@ static int ra_sum_pages(struct f2fs_sb_info *sbi,
>> struct list_head *pages,
>> f2fs_submit_page_mbio(sbi, page, page->index, &fio);
>>
>> f2fs_submit_merged_bio(sbi, META, READ);
>> - return 0;
>> +
>> + return page_idx - start;
>> }
>>
>> int restore_node_summary(struct f2fs_sb_info *sbi,
>> @@ -1630,28 +1624,30 @@ int restore_node_summary(struct f2fs_sb_info *sbi,
>> nrpages = min(last_offset - i, bio_blocks);
>>
>> /* read ahead node pages */
>> - err = ra_sum_pages(sbi, &page_list, addr, nrpages);
>> - if (err)
>> - return err;
>> + nrpages = ra_sum_pages(sbi, &page_list, addr, nrpages);
>> + if (!nrpages)
>> + return -ENOMEM;
>>
>> list_for_each_entry_safe(page, tmp, &page_list, lru) {
>> -
>
> Here we can just add:
> if (err)
> goto skip;
> lock_page();
> ...
> unlock_page();
> skip:
> list_del();
> __free_pages();
>
> IMO, it's more neat, so if you have any objection, let me know.
> Otherwise, I'll handle this by myself. :)
Thanks very much.
Regards,
Gu
> Thanks,
>
>> - lock_page(page);
>> - if (unlikely(!PageUptodate(page))) {
>> - err = -EIO;
>> - } else {
>> - rn = F2FS_NODE(page);
>> - sum_entry->nid = rn->footer.nid;
>> - sum_entry->version = 0;
>> - sum_entry->ofs_in_node = 0;
>> - sum_entry++;
>> + if (!err) {
>> + lock_page(page);
>> + if (unlikely(!PageUptodate(page))) {
>> + err = -EIO;
>> + } else {
>> + rn = F2FS_NODE(page);
>> + sum_entry->nid = rn->footer.nid;
>> + sum_entry->version = 0;
>> + sum_entry->ofs_in_node = 0;
>> + sum_entry++;
>> + }
>> + unlock_page(page);
>> }
>>
>> list_del(&page->lru);
>> - unlock_page(page);
>> __free_pages(page, 0);
>> }
>> }
>> +
>> return err;
>> }
>>
>> diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
>> index 199c964..b3f8431 100644
>> --- a/fs/f2fs/segment.c
>> +++ b/fs/f2fs/segment.c
>> @@ -1160,9 +1160,12 @@ static int read_normal_summaries(struct f2fs_sb_info
>> *sbi, int type)
>> ns->ofs_in_node = 0;
>> }
>> } else {
>> - if (restore_node_summary(sbi, segno, sum)) {
>> + int err;
>> +
>> + err = restore_node_summary(sbi, segno, sum);
>> + if (err) {
>> f2fs_put_page(new, 1);
>> - return -EINVAL;
>> + return err;
>> }
>> }
>> }
>
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