From f057f6cdf64175db1151b1f5d110e29904f119a1 Mon Sep 17 00:00:00 2001 From: Steven Whitehouse Date: Mon, 12 Jan 2009 10:43:39 +0000 Subject: GFS2: Merge lock_dlm module into GFS2 This is the big patch that I've been working on for some time now. There are many reasons for wanting to make this change such as: o Reducing overhead by eliminating duplicated fields between structures o Simplifcation of the code (reduces the code size by a fair bit) o The locking interface is now the DLM interface itself as proposed some time ago. o Fewer lookups of glocks when processing replies from the DLM o Fewer memory allocations/deallocations for each glock o Scope to do further optimisations in the future (but this patch is more than big enough for now!) Please note that (a) this patch relates to the lock_dlm module and not the DLM itself, that is still a separate module; and (b) that we retain the ability to build GFS2 as a standalone single node filesystem with out requiring the DLM. This patch needs a lot of testing, hence my keeping it I restarted my -git tree after the last merge window. That way, this has the maximum exposure before its merged. This is (modulo a few minor bug fixes) the same patch that I've been posting on and off the the last three months and its passed a number of different tests so far. Signed-off-by: Steven Whitehouse --- fs/gfs2/trans.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'fs/gfs2/trans.c') diff --git a/fs/gfs2/trans.c b/fs/gfs2/trans.c index f677b8a83f0..33cd523ec97 100644 --- a/fs/gfs2/trans.c +++ b/fs/gfs2/trans.c @@ -12,9 +12,8 @@ #include #include #include -#include #include -#include +#include #include "gfs2.h" #include "incore.h" -- cgit v1.2.3 From d8348de06f704fc34d24ec068546ecb1045fc11a Mon Sep 17 00:00:00 2001 From: Steven Whitehouse Date: Thu, 5 Feb 2009 10:12:38 +0000 Subject: GFS2: Fix deadlock on journal flush This patch fixes a deadlock when the journal is flushed and there are dirty inodes other than the one which caused the journal flush. Originally the journal flushing code was trying to obtain the transaction glock while running the flush code for an inode glock. We no longer require the transaction glock at this point in time since we know that any attempt to get the transaction glock from another node will result in a journal flush. So if we are flushing the journal, we can be sure that the transaction lock is still cached from when the transaction was started. By inlining a version of gfs2_trans_begin() (minus the bit which gets the transaction glock) we can avoid the deadlock problems caused if there is a demote request queued up on the transaction glock. In addition I've also moved the umount rwsem so that it covers the glock workqueue, since it all demotions are done by this workqueue now. That fixes a bug on umount which I came across while fixing the original problem. Reported-by: David Teigland Signed-off-by: Steven Whitehouse --- fs/gfs2/trans.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) (limited to 'fs/gfs2/trans.c') diff --git a/fs/gfs2/trans.c b/fs/gfs2/trans.c index 33cd523ec97..053752d4b27 100644 --- a/fs/gfs2/trans.c +++ b/fs/gfs2/trans.c @@ -87,9 +87,11 @@ void gfs2_trans_end(struct gfs2_sbd *sdp) if (!tr->tr_touched) { gfs2_log_release(sdp, tr->tr_reserved); - gfs2_glock_dq(&tr->tr_t_gh); - gfs2_holder_uninit(&tr->tr_t_gh); - kfree(tr); + if (tr->tr_t_gh.gh_gl) { + gfs2_glock_dq(&tr->tr_t_gh); + gfs2_holder_uninit(&tr->tr_t_gh); + kfree(tr); + } return; } @@ -105,9 +107,11 @@ void gfs2_trans_end(struct gfs2_sbd *sdp) } gfs2_log_commit(sdp, tr); - gfs2_glock_dq(&tr->tr_t_gh); - gfs2_holder_uninit(&tr->tr_t_gh); - kfree(tr); + if (tr->tr_t_gh.gh_gl) { + gfs2_glock_dq(&tr->tr_t_gh); + gfs2_holder_uninit(&tr->tr_t_gh); + kfree(tr); + } if (sdp->sd_vfs->s_flags & MS_SYNCHRONOUS) gfs2_log_flush(sdp, NULL); -- cgit v1.2.3