| From 309a85b6861fedbb48a22d45e0e079d1be993b3a Mon Sep 17 00:00:00 2001 |
| From: "Xiaowei.Hu" <xiaowei.hu@oracle.com> |
| Date: Wed, 27 Feb 2013 17:02:49 -0800 |
| Subject: ocfs2: ac->ac_allow_chain_relink=0 won't disable group relink |
| |
| From: "Xiaowei.Hu" <xiaowei.hu@oracle.com> |
| |
| commit 309a85b6861fedbb48a22d45e0e079d1be993b3a upstream. |
| |
| ocfs2_block_group_alloc_discontig() disables chain relink by setting |
| ac->ac_allow_chain_relink = 0 because it grabs clusters from multiple |
| cluster groups. |
| |
| It doesn't keep the credits for all chain relink,but |
| ocfs2_claim_suballoc_bits overrides this in this call trace: |
| ocfs2_block_group_claim_bits()->ocfs2_claim_clusters()-> |
| __ocfs2_claim_clusters()->ocfs2_claim_suballoc_bits() |
| ocfs2_claim_suballoc_bits set ac->ac_allow_chain_relink = 1; then call |
| ocfs2_search_chain() one time and disable it again, and then we run out |
| of credits. |
| |
| Fix is to allow relink by default and disable it in |
| ocfs2_block_group_alloc_discontig. |
| |
| Without this patch, End-users will run into a crash due to run out of |
| credits, backtrace like this: |
| |
| RIP: 0010:[<ffffffffa0808b14>] [<ffffffffa0808b14>] |
| jbd2_journal_dirty_metadata+0x164/0x170 [jbd2] |
| RSP: 0018:ffff8801b919b5b8 EFLAGS: 00010246 |
| RAX: 0000000000000000 RBX: ffff88022139ddc0 RCX: ffff880159f652d0 |
| RDX: ffff880178aa3000 RSI: ffff880159f652d0 RDI: ffff880087f09bf8 |
| RBP: ffff8801b919b5e8 R08: 0000000000000000 R09: 0000000000000000 |
| R10: 0000000000001e00 R11: 00000000000150b0 R12: ffff880159f652d0 |
| R13: ffff8801a0cae908 R14: ffff880087f09bf8 R15: ffff88018d177800 |
| FS: 00007fc9b0b6b6e0(0000) GS:ffff88022fd40000(0000) knlGS:0000000000000000 |
| CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b |
| CR2: 000000000040819c CR3: 0000000184017000 CR4: 00000000000006e0 |
| DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 |
| DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 |
| Process dd (pid: 9945, threadinfo ffff8801b919a000, task ffff880149a264c0) |
| Call Trace: |
| ocfs2_journal_dirty+0x2f/0x70 [ocfs2] |
| ocfs2_relink_block_group+0x111/0x480 [ocfs2] |
| ocfs2_search_chain+0x455/0x9a0 [ocfs2] |
| ... |
| |
| Signed-off-by: Xiaowei.Hu <xiaowei.hu@oracle.com> |
| Reviewed-by: Srinivas Eeda <srinivas.eeda@oracle.com> |
| Cc: Mark Fasheh <mfasheh@suse.com> |
| Cc: Joel Becker <jlbec@evilplan.org> |
| Signed-off-by: Andrew Morton <akpm@linux-foundation.org> |
| Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| fs/ocfs2/suballoc.c | 7 +++---- |
| fs/ocfs2/suballoc.h | 2 +- |
| 2 files changed, 4 insertions(+), 5 deletions(-) |
| |
| --- a/fs/ocfs2/suballoc.c |
| +++ b/fs/ocfs2/suballoc.c |
| @@ -642,7 +642,7 @@ ocfs2_block_group_alloc_discontig(handle |
| * cluster groups will be staying in cache for the duration of |
| * this operation. |
| */ |
| - ac->ac_allow_chain_relink = 0; |
| + ac->ac_disable_chain_relink = 1; |
| |
| /* Claim the first region */ |
| status = ocfs2_block_group_claim_bits(osb, handle, ac, min_bits, |
| @@ -1823,7 +1823,7 @@ static int ocfs2_search_chain(struct ocf |
| * Do this *after* figuring out how many bits we're taking out |
| * of our target group. |
| */ |
| - if (ac->ac_allow_chain_relink && |
| + if (!ac->ac_disable_chain_relink && |
| (prev_group_bh) && |
| (ocfs2_block_group_reasonably_empty(bg, res->sr_bits))) { |
| status = ocfs2_relink_block_group(handle, alloc_inode, |
| @@ -1928,7 +1928,6 @@ static int ocfs2_claim_suballoc_bits(str |
| |
| victim = ocfs2_find_victim_chain(cl); |
| ac->ac_chain = victim; |
| - ac->ac_allow_chain_relink = 1; |
| |
| status = ocfs2_search_chain(ac, handle, bits_wanted, min_bits, |
| res, &bits_left); |
| @@ -1947,7 +1946,7 @@ static int ocfs2_claim_suballoc_bits(str |
| * searching each chain in order. Don't allow chain relinking |
| * because we only calculate enough journal credits for one |
| * relink per alloc. */ |
| - ac->ac_allow_chain_relink = 0; |
| + ac->ac_disable_chain_relink = 1; |
| for (i = 0; i < le16_to_cpu(cl->cl_next_free_rec); i ++) { |
| if (i == victim) |
| continue; |
| --- a/fs/ocfs2/suballoc.h |
| +++ b/fs/ocfs2/suballoc.h |
| @@ -49,7 +49,7 @@ struct ocfs2_alloc_context { |
| |
| /* these are used by the chain search */ |
| u16 ac_chain; |
| - int ac_allow_chain_relink; |
| + int ac_disable_chain_relink; |
| group_search_t *ac_group_search; |
| |
| u64 ac_last_group; |