search for: trans_lock

...,6 @@ struct transaction { sem_t sem; uint32_t early_err; uint32_t err; - struct transaction *next; struct nbdkit_extents *extents; }; @@ -73,9 +72,6 @@ struct handle { int fds[2]; /* Pipe for kicking the reader thread */ bool readonly; pthread_t reader; - - pthread_mutex_t trans_lock; /* Covers access to trans list */ - struct transaction *trans; /* List of pending transactions */ }; /* Connect to server via absolute name of Unix socket */ @@ -306,7 +302,6 @@ void * nbdplug_reader (void *handle) { struct handle *h = handle; - int r; while (!nbd_aio_is_dead (h->...

...ite (h->nbd); - /* Check if we were kicked because a command was started */ - if (fds[1].revents & POLLIN && read (h->fds[0], &c, 1) != 1) { - nbdkit_error ("failed to read pipe: %m"); - break; - } - ACQUIRE_LOCK_FOR_CURRENT_SCOPE (&h->trans_lock); trans = h->trans; prev = &h->trans; @@ -400,7 +419,6 @@ static struct transaction * nbdplug_register (struct handle *h, int64_t cookie) { struct transaction *trans; - char c = 0; if (cookie == -1) { nbdkit_error ("command failed: %s", nbd_get_error ())...

I'm not observing any noticeable performance differences, but I'm liking the diffstat. I can't push this patch until we release a new libnbd version with the _notify API addition, but am posting it now for playing with things. Eric Blake (2): nbd: Move transaction info from heap to stack nbd: Use nbdkit aio_*_notify variants plugins/nbd/nbd.c | 217

With this, I am finally able to get the nbd plugin to do out-of-order responses to the client. Once this series goes in, we should be ready for Rich to cut a release. Eric Blake (4): nbd: Split reading into separate thread nbd: Protect writes with mutex nbd: Enable parallel handling tests: Test parallel nbd behavior plugins/nbd/nbd.c | 217

...,10 +156,8 @@ nbd_config_complete (void) /* The per-transaction details */ struct transaction { - union { - uint64_t cookie; - int fds[2]; - } u; + uint64_t cookie; + sem_t sem; void *buf; uint64_t offset; uint32_t count; @@ -182,6 +181,7 @@ struct handle { pthread_mutex_t trans_lock; /* Covers access to all fields below */ struct transaction *trans; + uint64_t unique; bool dead; }; @@ -264,7 +264,7 @@ find_trans_by_cookie (struct handle *h, uint64_t cookie, bool remove) ACQUIRE_LOCK_FOR_CURRENT_SCOPE (&h->trans_lock); ptr = &h->trans; while ((tr...

The reason the deadlock is that: Task Btrfs-cleaner umount() down_write(&s->s_umount) sync_filesystem() do auto-defragment and produce lots of dirty pages close_ctree() wait for the end of btrfs-cleaner start_transaction reserve space shrink_delalloc() writeback_inodes_sb_nr_if_idle()

...ol extents; + struct nbd_handle *nbd; + int fd; /* Cache of nbd_aio_get_fd */ + int fds[2]; /* Pipe for kicking the reader thread */ + bool readonly; pthread_t reader; - /* Prevents concurrent threads from interleaving writes to server */ - pthread_mutex_t write_lock; - - pthread_mutex_t trans_lock; /* Covers access to all fields below */ - struct transaction *trans; - uint64_t unique; - bool dead; + pthread_mutex_t trans_lock; /* Covers access to trans list */ + struct transaction *trans; /* List of pending transactions */ }; /* Connect to server via absolute name of Unix socket */ @...

...ol extents; + struct nbd_handle *nbd; + int fd; /* Cache of nbd_aio_get_fd */ + int fds[2]; /* Pipe for kicking the reader thread */ + bool readonly; pthread_t reader; - /* Prevents concurrent threads from interleaving writes to server */ - pthread_mutex_t write_lock; - - pthread_mutex_t trans_lock; /* Covers access to all fields below */ - struct transaction *trans; - uint64_t unique; - bool dead; + pthread_mutex_t trans_lock; /* Covers access to trans list */ + struct transaction *trans; /* List of pending transactions */ }; /* Connect to server via absolute name of Unix socket */ @...

...*/ -struct handle { - /* These fields are read-only once initialized */ - int fd; - int flags; - int64_t size; - bool structured; - bool extents; - pthread_t reader; - - /* Prevents concurrent threads from interleaving writes to server */ - pthread_mutex_t write_lock; - - pthread_mutex_t trans_lock; /* Covers access to all fields below */ - struct transaction *trans; - uint64_t unique; - bool dead; -}; - -/* Connect to server via absolute name of Unix socket */ -static char *sockname; - -/* Connect to server via TCP socket */ -static const char *hostname; -static const char *port; - -/* Hu...

Patch 1 played with an early draft of Rich's Fedora 30 libnbd package: https://bugzilla.redhat.com/show_bug.cgi?id=1713767#c17 Note that comment 21 provides a newer package 0.1.1-1 with a different API; and that libnbd has more unreleased API changes in the pipeline (whether that will be called 0.2 or 0.1.2); so we'll have to tweak things based on what is actually available in distros.

libnbd-0.1.2-1 is now available in Fedora 29/30 updates-testing, although it was not compiled against libxml2 so it lacks uri support (I ended up testing patch 4 with a self-built libnbd). Diffs since v1 - rebase to master, bump from libnbd 0.1 to 0.1.2, add URI support, better timing results Still not done - patch 5 needs associated tests Eric Blake (5): nbd: Check for libnbd nbd:

...0, 0, NULL); shutdown (h->fd, SHUT_WR); } - close (h->fd); if ((errno = pthread_join (h->reader, NULL))) nbdkit_debug ("failed to join reader thread: %m"); + close (h->fd); pthread_mutex_destroy (&h->write_lock); pthread_mutex_destroy (&h->trans_lock); free (h); -- 2.17.2

...*/ +struct handle { + /* These fields are read-only once initialized */ + int fd; + int flags; + int64_t size; + bool structured; + bool extents; + pthread_t reader; + + /* Prevents concurrent threads from interleaving writes to server */ + pthread_mutex_t write_lock; + + pthread_mutex_t trans_lock; /* Covers access to all fields below */ + struct transaction *trans; + uint64_t unique; + bool dead; +}; + /* Connect to server via absolute name of Unix socket */ static char *sockname; @@ -73,9 +104,18 @@ static const char *export; /* Number of retries */ static unsigned long retry; +/*...

libnbd-0.1.4-1 is now available in Fedora 29/30 updates testing. Diffs since v2 - rebase to master, bump from libnbd 0.1.2 to 0.1.3+, add tests to TLS usage which flushed out the need to turn relative pathnames into absolute, doc tweaks Now that the testsuite covers TLS and libnbd has been fixed to provide the things I found lacking when developing v2, I'm leaning towards pushing this on

I got annoyed by qemu-nbd's default of only allowing a single connection; combine that with nbdkit's nbd plugin, and even 'qemu-nbd --list' of nbdkit counts as the single connection and immediately hangs up. If we introduce a shared mode, then 'qemu-nbd --list' can connect as many times as it wants without killing the original qemu-nbd wrapped by nbdkit. But this in turn

...ransaction_wait)) @@ -3907,8 +3907,6 @@ int btrfs_cleanup_transaction(struct btrfs_root *root) btrfs_destroy_delayed_inodes(root); btrfs_assert_delayed_root_empty(root); - btrfs_destroy_pending_snapshots(t); - btrfs_destroy_delalloc_inodes(root); spin_lock(&root->fs_info->trans_lock); diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index b908960..94c0e42 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -596,12 +596,8 @@ static int create_snapshot(struct btrfs_root *root, struct inode *dir, ret = btrfs_commit_transaction(trans, root->fs_info->exten...

Hi Eric, There's a memory leak in the nbd client. The message (below) is not very useful because somehow debuginfo is missing in the plugin. However it's easily reproducible by doing: make check-valgrind TESTS=test-nbd I tried the attached patch to fix what I thought was the bug, but sadly the fix doesn't work for me :-( So I guess something else is going on, but it does look as

...service name to use (default 10809).\n" \ + "export=<NAME> Export name to connect to (default \"\").\n" \ #define THREAD_MODEL NBDKIT_THREAD_MODEL_PARALLEL @@ -199,7 +239,7 @@ nbd_mark_dead (struct handle *h) ACQUIRE_LOCK_FOR_CURRENT_SCOPE (&h->trans_lock); if (!h->dead) { nbdkit_debug ("permanent failure while talking to server %s: %m", - sockname); + servname); h->dead = true; } else if (!err) @@ -861,6 +901,45 @@ nbd_connect_unix(struct handle *h) return 0; } +/* Connect to...

...e int commit_cowonly_roots(struct btrfs_trans_handle *trans, * a dirty root struct and adds it into the list of dead roots that need to * be deleted */ -int btrfs_add_dead_root(struct btrfs_root *root) +void btrfs_add_dead_root(struct btrfs_root *root) { spin_lock(&root->fs_info->trans_lock); list_add(&root->root_list, &root->fs_info->dead_roots); spin_unlock(&root->fs_info->trans_lock); - return 0; } /* @@ -1232,8 +1231,7 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans, if (flush_on_commit || snap_pending) { btrfs_start_del...

Accepting only Unix sockets can be a bit limiting; let's be more flexible. Eric Blake (2): nbd: Refactor Unix socket connection nbd: Support TCP socket plugins/nbd/nbdkit-nbd-plugin.pod | 36 ++++-- plugins/nbd/nbd.c | 175 ++++++++++++++++++++++-------- TODO | 3 - 3 files changed, 161 insertions(+), 53 deletions(-) -- 2.20.1