diff options
Diffstat (limited to 'debian')
9 files changed, 0 insertions, 2589 deletions
diff --git a/debian/patches/0001-tmpfs-use-a-thread-timeout.patch b/debian/patches/0001-tmpfs-use-a-thread-timeout.patch deleted file mode 100644 index a5f7bef7..00000000 --- a/debian/patches/0001-tmpfs-use-a-thread-timeout.patch +++ /dev/null @@ -1,36 +0,0 @@ -From be3c1c3841192b4e85a0063d3893a9f8ff062b4d Mon Sep 17 00:00:00 2001 -From: Justus Winter <4winter@informatik.uni-hamburg.de> -Date: Wed, 28 May 2014 16:18:23 +0200 -Subject: [PATCH 1/8] tmpfs: use a thread timeout - -There is no need to keep all the threads around, just the master -thread. - -* tmpfs/tmpfs (diskfs_thread_function): Use a thread timeout. ---- - tmpfs/tmpfs.c | 3 ++- - 1 file changed, 2 insertions(+), 1 deletion(-) - -diff --git a/tmpfs/tmpfs.c b/tmpfs/tmpfs.c -index a45d343..718c6d8 100644 ---- a/tmpfs/tmpfs.c -+++ b/tmpfs/tmpfs.c -@@ -296,13 +296,14 @@ diskfs_append_args (char **argz, size_t *argz_len) - static void * - diskfs_thread_function (void *demuxer) - { -+ static int thread_timeout = 1000 * 60 * 2; /* two minutes */ - error_t err; - - do - { - ports_manage_port_operations_multithread (diskfs_port_bucket, - (ports_demuxer_type) demuxer, -- 0, -+ thread_timeout, - 0, - 0); - err = diskfs_shutdown (0); --- -2.0.0.rc2 - diff --git a/debian/patches/0002-libports-use-a-global-hash-table-for-the-lookups.patch b/debian/patches/0002-libports-use-a-global-hash-table-for-the-lookups.patch deleted file mode 100644 index dbf599fd..00000000 --- a/debian/patches/0002-libports-use-a-global-hash-table-for-the-lookups.patch +++ /dev/null @@ -1,668 +0,0 @@ -From 1d637232cbff225235bcc4bafbb6b0f4a2559295 Mon Sep 17 00:00:00 2001 -From: Justus Winter <4winter@informatik.uni-hamburg.de> -Date: Sat, 3 May 2014 03:53:41 +0200 -Subject: [PATCH 2/8] libports: use a global hash table for the lookups - -Previously, libports used a hash table per port bucket. This makes -looking up a port difficult if one does not know the port bucket, as -one has to iterate over all buckets and do a hash table lookup each. - -Having to iterate over the buckets makes it necessary to keep a list -of all buckets, which has to be updated and protected by a lock as -well. - -Also, the current code in _ports_bucket_class_iterate iterates over -the hash table associated with the bucket given. When -ports_class_iterate calls this common function, it obtains a reference -to the bucket from one of the ports in the given class. This will not -work if a class contains ports in different port buckets. This -limitation is not documented as far as I can see. Again, having to -maintain this list has its cost and requires serialization. - -Use a global hash table for lookups instead. Keep the per-bucket hash -tables for efficient iteration over buckets. Furthermore, serialize -access to all hash tables using a separate lock. Remove the linked -lists of all buckets and all ports in a class. - -* libports/bucket-iterate.c (ports_bucket_iterate): Acquire -_ports_htable_lock. Also, generalize ports_bucket_iterate so that it -takes a pointer to a hash table as first argument. -(ports_bucket_iterate): Ajust call to former function accordingly. -* libports/class-iterate.c (ports_class_iterate): Just call the -generalized _ports_bucket_class_iterate with the global hash table as -argument. -* libports/ports.h (struct port_info): Remove the port class links. -(struct port_bucket): Remove the hash table, and the all buckets link. -(_ports_all_buckets): Remove declaration. -(_ports_htable): New global hash table. -(_ports_htable_lock): Protected by this lock. -* libports/claim-right.c: Adjust accordingly. -* libports/complete-deallocate.c: Likewise. -* libports/create-bucket.c: Likewise. -* libports/create-class.c: Likewise. -* libports/create-internal.c: Likewise. -* libports/destroy-right.c: Likewise. -* libports/import-port.c: Likewise. -* libports/lookup-port.c: Likewise. -* libports/reallocate-from-external.c: Likewise. -* libports/reallocate-port.c: Likewise. -* libports/transfer-right.c: Likewise. -* libports/inhibit-all-rpcs.c: Iterate over the hash table. -* libports/inhibit-bucket-rpcs.c: Likewise, but filter using bucket. -* libports/inhibit-class-rpcs.c: Likewise, but filter using class. -* libports/init.c (_ports_htable): Initialize. -(_ports_htable_lock): Likewise. ---- - libports/bucket-iterate.c | 22 +++++++++++++++------- - libports/claim-right.c | 5 ++++- - libports/class-iterate.c | 10 +--------- - libports/complete-deallocate.c | 7 +++---- - libports/create-bucket.c | 6 ------ - libports/create-class.c | 1 - - libports/create-internal.c | 19 +++++++++++++------ - libports/destroy-right.c | 5 +++-- - libports/import-port.c | 19 +++++++++++++------ - libports/inhibit-all-rpcs.c | 27 +++++++++++++-------------- - libports/inhibit-bucket-rpcs.c | 3 ++- - libports/inhibit-class-rpcs.c | 27 ++++++++++++++++++--------- - libports/init.c | 7 ++++++- - libports/lookup-port.c | 23 +++++++++-------------- - libports/ports.h | 22 +++++++++++++++++----- - libports/reallocate-from-external.c | 15 +++++++++++---- - libports/reallocate-port.c | 9 ++++++++- - libports/transfer-right.c | 18 ++++++++++++++---- - 18 files changed, 150 insertions(+), 95 deletions(-) - -diff --git a/libports/bucket-iterate.c b/libports/bucket-iterate.c -index babc204..88f082f 100644 ---- a/libports/bucket-iterate.c -+++ b/libports/bucket-iterate.c -@@ -25,7 +25,7 @@ - /* Internal entrypoint for both ports_bucket_iterate and ports_class_iterate. - If CLASS is non-null, call FUN only for ports in that class. */ - error_t --_ports_bucket_class_iterate (struct port_bucket *bucket, -+_ports_bucket_class_iterate (struct hurd_ihash *ht, - struct port_class *class, - error_t (*fun)(void *)) - { -@@ -36,23 +36,24 @@ _ports_bucket_class_iterate (struct port_bucket *bucket, - error_t err; - - pthread_mutex_lock (&_ports_lock); -+ pthread_rwlock_rdlock (&_ports_htable_lock); - -- if (bucket->htable.nr_items == 0) -+ if (ht->nr_items == 0) - { -- pthread_mutex_unlock (&_ports_lock); -+ pthread_rwlock_unlock (&_ports_htable_lock); - return 0; - } - -- nr_items = bucket->htable.nr_items; -+ nr_items = ht->nr_items; - p = malloc (nr_items * sizeof *p); - if (p == NULL) - { -- pthread_mutex_unlock (&_ports_lock); -+ pthread_rwlock_unlock (&_ports_htable_lock); - return ENOMEM; - } - - n = 0; -- HURD_IHASH_ITERATE (&bucket->htable, arg) -+ HURD_IHASH_ITERATE (ht, arg) - { - struct port_info *const pi = arg; - -@@ -63,8 +64,15 @@ _ports_bucket_class_iterate (struct port_bucket *bucket, - n++; - } - } -+ pthread_rwlock_unlock (&_ports_htable_lock); - pthread_mutex_unlock (&_ports_lock); - -+ if (n == 0) -+ { -+ free (p); -+ return 0; -+ } -+ - if (n != nr_items) - { - /* We allocated too much. Release unused memory. */ -@@ -89,5 +97,5 @@ error_t - ports_bucket_iterate (struct port_bucket *bucket, - error_t (*fun)(void *)) - { -- return _ports_bucket_class_iterate (bucket, 0, fun); -+ return _ports_bucket_class_iterate (&bucket->htable, NULL, fun); - } -diff --git a/libports/claim-right.c b/libports/claim-right.c -index 4851ea3..85592ff 100644 ---- a/libports/claim-right.c -+++ b/libports/claim-right.c -@@ -34,10 +34,13 @@ ports_claim_right (void *portstruct) - if (ret == MACH_PORT_NULL) - return ret; - -- pthread_mutex_lock (&_ports_lock); -+ pthread_rwlock_wrlock (&_ports_htable_lock); -+ hurd_ihash_locp_remove (&_ports_htable, pi->ports_htable_entry); - hurd_ihash_locp_remove (&pi->bucket->htable, pi->hentry); -+ pthread_rwlock_unlock (&_ports_htable_lock); - err = mach_port_move_member (mach_task_self (), ret, MACH_PORT_NULL); - assert_perror (err); -+ pthread_mutex_lock (&_ports_lock); - pi->port_right = MACH_PORT_NULL; - if (pi->flags & PORT_HAS_SENDRIGHTS) - { -diff --git a/libports/class-iterate.c b/libports/class-iterate.c -index 1f8878a..df33818 100644 ---- a/libports/class-iterate.c -+++ b/libports/class-iterate.c -@@ -23,13 +23,5 @@ error_t - ports_class_iterate (struct port_class *class, - error_t (*fun)(void *)) - { -- pthread_mutex_lock (&_ports_lock); -- if (class->ports != 0) -- { -- struct port_bucket *bucket = class->ports->bucket; -- pthread_mutex_unlock (&_ports_lock); -- return _ports_bucket_class_iterate (bucket, class, fun); -- } -- pthread_mutex_unlock (&_ports_lock); -- return 0; -+ return _ports_bucket_class_iterate (&_ports_htable, class, fun); - } -diff --git a/libports/complete-deallocate.c b/libports/complete-deallocate.c -index 8ce095b..4768dab 100644 ---- a/libports/complete-deallocate.c -+++ b/libports/complete-deallocate.c -@@ -29,16 +29,15 @@ _ports_complete_deallocate (struct port_info *pi) - - if (pi->port_right) - { -+ pthread_rwlock_wrlock (&_ports_htable_lock); -+ hurd_ihash_locp_remove (&_ports_htable, pi->ports_htable_entry); - hurd_ihash_locp_remove (&pi->bucket->htable, pi->hentry); -+ pthread_rwlock_unlock (&_ports_htable_lock); - mach_port_mod_refs (mach_task_self (), pi->port_right, - MACH_PORT_RIGHT_RECEIVE, -1); - pi->port_right = MACH_PORT_NULL; - } - -- *pi->prevp = pi->next; -- if (pi->next) -- pi->next->prevp = pi->prevp; -- - pi->bucket->count--; - pi->class->count--; - -diff --git a/libports/create-bucket.c b/libports/create-bucket.c -index 52d50c3..2c5f1b6 100644 ---- a/libports/create-bucket.c -+++ b/libports/create-bucket.c -@@ -48,11 +48,5 @@ ports_create_bucket () - - hurd_ihash_init (&ret->htable, offsetof (struct port_info, hentry)); - ret->rpcs = ret->flags = ret->count = 0; -- -- pthread_mutex_lock (&_ports_lock); -- ret->next = _ports_all_buckets; -- _ports_all_buckets = ret; -- pthread_mutex_unlock (&_ports_lock); -- - return ret; - } -diff --git a/libports/create-class.c b/libports/create-class.c -index 12c8add..782f52b 100644 ---- a/libports/create-class.c -+++ b/libports/create-class.c -@@ -39,7 +39,6 @@ ports_create_class (void (*clean_routine)(void *), - cl->dropweak_routine = dropweak_routine; - cl->flags = 0; - cl->rpcs = 0; -- cl->ports = NULL; - cl->count = 0; - cl->uninhibitable_rpcs = ports_default_uninhibitable_rpcs; - -diff --git a/libports/create-internal.c b/libports/create-internal.c -index 8551297..8543986 100644 ---- a/libports/create-internal.c -+++ b/libports/create-internal.c -@@ -81,15 +81,22 @@ _ports_create_port_internal (struct port_class *class, - goto loop; - } - -+ pthread_rwlock_wrlock (&_ports_htable_lock); -+ err = hurd_ihash_add (&_ports_htable, port, pi); -+ if (err) -+ { -+ pthread_rwlock_unlock (&_ports_htable_lock); -+ goto lose; -+ } - err = hurd_ihash_add (&bucket->htable, port, pi); - if (err) -- goto lose; -+ { -+ hurd_ihash_locp_remove (&_ports_htable, pi->ports_htable_entry); -+ pthread_rwlock_unlock (&_ports_htable_lock); -+ goto lose; -+ } -+ pthread_rwlock_unlock (&_ports_htable_lock); - -- pi->next = class->ports; -- pi->prevp = &class->ports; -- if (class->ports) -- class->ports->prevp = &pi->next; -- class->ports = pi; - bucket->count++; - class->count++; - pthread_mutex_unlock (&_ports_lock); -diff --git a/libports/destroy-right.c b/libports/destroy-right.c -index 65e19c7..448b379 100644 ---- a/libports/destroy-right.c -+++ b/libports/destroy-right.c -@@ -30,12 +30,13 @@ ports_destroy_right (void *portstruct) - - if (pi->port_right != MACH_PORT_NULL) - { -- pthread_mutex_lock (&_ports_lock); -+ pthread_rwlock_wrlock (&_ports_htable_lock); -+ hurd_ihash_locp_remove (&_ports_htable, pi->ports_htable_entry); - hurd_ihash_locp_remove (&pi->bucket->htable, pi->hentry); -+ pthread_rwlock_unlock (&_ports_htable_lock); - err = mach_port_mod_refs (mach_task_self (), pi->port_right, - MACH_PORT_RIGHT_RECEIVE, -1); - assert_perror (err); -- pthread_mutex_unlock (&_ports_lock); - - pi->port_right = MACH_PORT_NULL; - -diff --git a/libports/import-port.c b/libports/import-port.c -index 226f47e..2660672 100644 ---- a/libports/import-port.c -+++ b/libports/import-port.c -@@ -75,15 +75,22 @@ ports_import_port (struct port_class *class, struct port_bucket *bucket, - goto loop; - } - -+ pthread_rwlock_wrlock (&_ports_htable_lock); -+ err = hurd_ihash_add (&_ports_htable, port, pi); -+ if (err) -+ { -+ pthread_rwlock_unlock (&_ports_htable_lock); -+ goto lose; -+ } - err = hurd_ihash_add (&bucket->htable, port, pi); - if (err) -- goto lose; -+ { -+ hurd_ihash_locp_remove (&_ports_htable, pi->ports_htable_entry); -+ pthread_rwlock_unlock (&_ports_htable_lock); -+ goto lose; -+ } -+ pthread_rwlock_unlock (&_ports_htable_lock); - -- pi->next = class->ports; -- pi->prevp = &class->ports; -- if (class->ports) -- class->ports->prevp = &pi->next; -- class->ports = pi; - bucket->count++; - class->count++; - pthread_mutex_unlock (&_ports_lock); -diff --git a/libports/inhibit-all-rpcs.c b/libports/inhibit-all-rpcs.c -index d4a54ba..27e2ec5 100644 ---- a/libports/inhibit-all-rpcs.c -+++ b/libports/inhibit-all-rpcs.c -@@ -36,24 +36,23 @@ ports_inhibit_all_rpcs () - struct port_bucket *bucket; - int this_one = 0; - -- for (bucket = _ports_all_buckets; bucket; bucket = bucket->next) -+ pthread_rwlock_rdlock (&_ports_htable_lock); -+ HURD_IHASH_ITERATE (&_ports_htable, portstruct) - { -- HURD_IHASH_ITERATE (&bucket->htable, portstruct) -+ struct rpc_info *rpc; -+ struct port_info *pi = portstruct; -+ -+ for (rpc = pi->current_rpcs; rpc; rpc = rpc->next) - { -- struct rpc_info *rpc; -- struct port_info *pi = portstruct; -- -- for (rpc = pi->current_rpcs; rpc; rpc = rpc->next) -- { -- /* Avoid cancelling the calling thread if it's currently -- handling a RPC. */ -- if (rpc->thread == hurd_thread_self ()) -- this_one = 1; -- else -- hurd_thread_cancel (rpc->thread); -- } -+ /* Avoid cancelling the calling thread if it's currently -+ handling a RPC. */ -+ if (rpc->thread == hurd_thread_self ()) -+ this_one = 1; -+ else -+ hurd_thread_cancel (rpc->thread); - } - } -+ pthread_rwlock_unlock (&_ports_htable_lock); - - while (_ports_total_rpcs > this_one) - { -diff --git a/libports/inhibit-bucket-rpcs.c b/libports/inhibit-bucket-rpcs.c -index 965aa03..82efdf5 100644 ---- a/libports/inhibit-bucket-rpcs.c -+++ b/libports/inhibit-bucket-rpcs.c -@@ -35,6 +35,7 @@ ports_inhibit_bucket_rpcs (struct port_bucket *bucket) - { - int this_one = 0; - -+ pthread_rwlock_rdlock (&_ports_htable_lock); - HURD_IHASH_ITERATE (&bucket->htable, portstruct) - { - struct rpc_info *rpc; -@@ -49,7 +50,7 @@ ports_inhibit_bucket_rpcs (struct port_bucket *bucket) - hurd_thread_cancel (rpc->thread); - } - } -- -+ pthread_rwlock_unlock (&_ports_htable_lock); - - while (bucket->rpcs > this_one) - { -diff --git a/libports/inhibit-class-rpcs.c b/libports/inhibit-class-rpcs.c -index 7ee8653..9a87a5f 100644 ---- a/libports/inhibit-class-rpcs.c -+++ b/libports/inhibit-class-rpcs.c -@@ -36,15 +36,24 @@ ports_inhibit_class_rpcs (struct port_class *class) - struct rpc_info *rpc; - int this_one = 0; - -- for (pi = class->ports; pi; pi = pi->next) -- for (rpc = pi->current_rpcs; rpc; rpc = rpc->next) -- { -- /* Avoid cancelling the calling thread. */ -- if (rpc->thread == hurd_thread_self ()) -- this_one = 1; -- else -- hurd_thread_cancel (rpc->thread); -- } -+ pthread_rwlock_rdlock (&_ports_htable_lock); -+ HURD_IHASH_ITERATE (&_ports_htable, portstruct) -+ { -+ struct rpc_info *rpc; -+ struct port_info *pi = portstruct; -+ if (pi->class != class) -+ continue; -+ -+ for (rpc = pi->current_rpcs; rpc; rpc = rpc->next) -+ { -+ /* Avoid cancelling the calling thread. */ -+ if (rpc->thread == hurd_thread_self ()) -+ this_one = 1; -+ else -+ hurd_thread_cancel (rpc->thread); -+ } -+ } -+ pthread_rwlock_unlock (&_ports_htable_lock); - - while (class->rpcs > this_one) - { -diff --git a/libports/init.c b/libports/init.c -index 3ef5388..4a68cb8 100644 ---- a/libports/init.c -+++ b/libports/init.c -@@ -19,9 +19,14 @@ - Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ - - #include "ports.h" -+#include <stddef.h> - - pthread_mutex_t _ports_lock = PTHREAD_MUTEX_INITIALIZER; - pthread_cond_t _ports_block = PTHREAD_COND_INITIALIZER; --struct port_bucket *_ports_all_buckets; -+ -+struct hurd_ihash _ports_htable = -+ HURD_IHASH_INITIALIZER (offsetof (struct port_info, ports_htable_entry)); -+pthread_rwlock_t _ports_htable_lock = PTHREAD_RWLOCK_INITIALIZER; -+ - int _ports_total_rpcs; - int _ports_flags; -diff --git a/libports/lookup-port.c b/libports/lookup-port.c -index f79f6f0..858ee11 100644 ---- a/libports/lookup-port.c -+++ b/libports/lookup-port.c -@@ -26,27 +26,22 @@ ports_lookup_port (struct port_bucket *bucket, - mach_port_t port, - struct port_class *class) - { -- struct port_info *pi = 0; -- -+ struct port_info *pi; -+ - pthread_mutex_lock (&_ports_lock); -+ pthread_rwlock_rdlock (&_ports_htable_lock); - -- if (bucket) -- pi = hurd_ihash_find (&bucket->htable, port); -- else -- for (bucket = _ports_all_buckets; bucket; bucket = bucket->next) -- { -- pi = hurd_ihash_find (&bucket->htable, port); -- if (pi) -- break; -- } -- -- if (pi && class && pi->class != class) -+ pi = hurd_ihash_find (&_ports_htable, port); -+ if (pi -+ && ((class && pi->class != class) -+ || (bucket && pi->bucket != bucket))) - pi = 0; - - if (pi) - pi->refcnt++; - -+ pthread_rwlock_unlock (&_ports_htable_lock); - pthread_mutex_unlock (&_ports_lock); -- -+ - return pi; - } -diff --git a/libports/ports.h b/libports/ports.h -index 7f13124..6922162 100644 ---- a/libports/ports.h -+++ b/libports/ports.h -@@ -48,7 +48,7 @@ struct port_info - struct rpc_info *current_rpcs; - struct port_bucket *bucket; - hurd_ihash_locp_t hentry; -- struct port_info *next, **prevp; /* links on port_class list */ -+ hurd_ihash_locp_t ports_htable_entry; - }; - typedef struct port_info *port_info_t; - -@@ -61,11 +61,12 @@ typedef struct port_info *port_info_t; - struct port_bucket - { - mach_port_t portset; -+ /* Per-bucket hash table used for fast iteration. Access must be -+ serialized using _ports_htable_lock. */ - struct hurd_ihash htable; - int rpcs; - int flags; - int count; -- struct port_bucket *next; - }; - /* FLAGS above are the following: */ - #define PORT_BUCKET_INHIBITED PORTS_INHIBITED -@@ -78,7 +79,6 @@ struct port_class - { - int flags; - int rpcs; -- struct port_info *ports; - int count; - void (*clean_routine) (void *); - void (*dropweak_routine) (void *); -@@ -277,7 +277,7 @@ error_t ports_class_iterate (struct port_class *class, - error_t (*fun)(void *port)); - - /* Internal entrypoint for above two. */ --error_t _ports_bucket_class_iterate (struct port_bucket *bucket, -+error_t _ports_bucket_class_iterate (struct hurd_ihash *ht, - struct port_class *class, - error_t (*fun)(void *port)); - -@@ -402,7 +402,19 @@ extern kern_return_t - /* Private data */ - extern pthread_mutex_t _ports_lock; - extern pthread_cond_t _ports_block; --extern struct port_bucket *_ports_all_buckets; -+ -+/* A global hash table mapping port names to port_info objects. This -+ table is used for port lookups and to iterate over classes. -+ -+ A port in this hash table carries an implicit light reference. -+ When the reference counts reach zero, we call -+ _ports_complete_deallocate. There we reacquire our lock -+ momentarily to check whether someone else reacquired a reference -+ through the hash table. */ -+extern struct hurd_ihash _ports_htable; -+/* Access to the hash table is protected by this lock. */ -+extern pthread_rwlock_t _ports_htable_lock; -+ - extern int _ports_total_rpcs; - extern int _ports_flags; - #define _PORTS_INHIBITED PORTS_INHIBITED -diff --git a/libports/reallocate-from-external.c b/libports/reallocate-from-external.c -index 8cccb2a..9944b39 100644 ---- a/libports/reallocate-from-external.c -+++ b/libports/reallocate-from-external.c -@@ -43,8 +43,11 @@ ports_reallocate_from_external (void *portstruct, mach_port_t receive) - MACH_PORT_RIGHT_RECEIVE, -1); - assert_perror (err); - -+ pthread_rwlock_wrlock (&_ports_htable_lock); -+ hurd_ihash_locp_remove (&_ports_htable, pi->ports_htable_entry); - hurd_ihash_locp_remove (&pi->bucket->htable, pi->hentry); -- -+ pthread_rwlock_unlock (&_ports_htable_lock); -+ - if ((pi->flags & PORT_HAS_SENDRIGHTS) && !stat.mps_srights) - { - dropref = 1; -@@ -59,11 +62,15 @@ ports_reallocate_from_external (void *portstruct, mach_port_t receive) - pi->port_right = receive; - pi->cancel_threshold = 0; - pi->mscount = stat.mps_mscount; -- -- err = hurd_ihash_add (&pi->bucket->htable, receive, pi); -+ -+ pthread_rwlock_wrlock (&_ports_htable_lock); -+ err = hurd_ihash_add (&_ports_htable, receive, pi); - assert_perror (err); -+ err = hurd_ihash_add (&pi->bucket->htable, receive, pi); -+ pthread_rwlock_unlock (&_ports_htable_lock); - pthread_mutex_unlock (&_ports_lock); -- -+ assert_perror (err); -+ - mach_port_move_member (mach_task_self (), receive, pi->bucket->portset); - - if (stat.mps_srights) -diff --git a/libports/reallocate-port.c b/libports/reallocate-port.c -index d2adaeb..cc534eb 100644 ---- a/libports/reallocate-port.c -+++ b/libports/reallocate-port.c -@@ -36,7 +36,10 @@ ports_reallocate_port (void *portstruct) - MACH_PORT_RIGHT_RECEIVE, -1); - assert_perror (err); - -+ pthread_rwlock_wrlock (&_ports_htable_lock); -+ hurd_ihash_locp_remove (&_ports_htable, pi->ports_htable_entry); - hurd_ihash_locp_remove (&pi->bucket->htable, pi->hentry); -+ pthread_rwlock_unlock (&_ports_htable_lock); - - err = mach_port_allocate (mach_task_self (), MACH_PORT_RIGHT_RECEIVE, - &pi->port_right); -@@ -48,9 +51,13 @@ ports_reallocate_port (void *portstruct) - } - pi->cancel_threshold = 0; - pi->mscount = 0; -- err = hurd_ihash_add (&pi->bucket->htable, pi->port_right, pi); -+ pthread_rwlock_wrlock (&_ports_htable_lock); -+ err = hurd_ihash_add (&_ports_htable, pi->port_right, pi); - assert_perror (err); -+ err = hurd_ihash_add (&pi->bucket->htable, pi->port_right, pi); -+ pthread_rwlock_unlock (&_ports_htable_lock); - pthread_mutex_unlock (&_ports_lock); -+ assert_perror (err); - - err = mach_port_move_member (mach_task_self (), pi->port_right, - pi->bucket->portset); -diff --git a/libports/transfer-right.c b/libports/transfer-right.c -index 72488a9..3f48290 100644 ---- a/libports/transfer-right.c -+++ b/libports/transfer-right.c -@@ -41,7 +41,10 @@ ports_transfer_right (void *tostruct, - port = frompi->port_right; - if (port != MACH_PORT_NULL) - { -+ pthread_rwlock_wrlock (&_ports_htable_lock); -+ hurd_ihash_locp_remove (&_ports_htable, frompi->ports_htable_entry); - hurd_ihash_locp_remove (&frompi->bucket->htable, frompi->hentry); -+ pthread_rwlock_unlock (&_ports_htable_lock); - frompi->port_right = MACH_PORT_NULL; - if (frompi->flags & PORT_HAS_SENDRIGHTS) - { -@@ -54,7 +57,10 @@ ports_transfer_right (void *tostruct, - /* Destroy the existing right in TOPI. */ - if (topi->port_right != MACH_PORT_NULL) - { -+ pthread_rwlock_wrlock (&_ports_htable_lock); -+ hurd_ihash_locp_remove (&_ports_htable, topi->ports_htable_entry); - hurd_ihash_locp_remove (&topi->bucket->htable, topi->hentry); -+ pthread_rwlock_unlock (&_ports_htable_lock); - err = mach_port_mod_refs (mach_task_self (), topi->port_right, - MACH_PORT_RIGHT_RECEIVE, -1); - assert_perror (err); -@@ -74,10 +80,16 @@ ports_transfer_right (void *tostruct, - topi->port_right = port; - topi->cancel_threshold = frompi->cancel_threshold; - topi->mscount = frompi->mscount; -- -+ -+ pthread_mutex_unlock (&_ports_lock); -+ - if (port) - { -+ pthread_rwlock_wrlock (&_ports_htable_lock); -+ err = hurd_ihash_add (&_ports_htable, port, topi); -+ assert_perror (err); - err = hurd_ihash_add (&topi->bucket->htable, port, topi); -+ pthread_rwlock_unlock (&_ports_htable_lock); - assert_perror (err); - if (topi->bucket != frompi->bucket) - { -@@ -86,9 +98,7 @@ ports_transfer_right (void *tostruct, - assert_perror (err); - } - } -- -- pthread_mutex_unlock (&_ports_lock); -- -+ - /* Take care of any lowered reference counts. */ - if (dereffrompi) - ports_port_deref (frompi); --- -2.0.0.rc2 - diff --git a/debian/patches/0003-libports-lock-less-reference-counting-for-port_info-.patch b/debian/patches/0003-libports-lock-less-reference-counting-for-port_info-.patch deleted file mode 100644 index b588f458..00000000 --- a/debian/patches/0003-libports-lock-less-reference-counting-for-port_info-.patch +++ /dev/null @@ -1,344 +0,0 @@ -From 9b7b6c19b25420108f2cfeefb881ddeab09c3063 Mon Sep 17 00:00:00 2001 -From: Justus Winter <4winter@informatik.uni-hamburg.de> -Date: Sat, 3 May 2014 01:02:35 +0200 -Subject: [PATCH 3/8] libports: lock-less reference counting for port_info - objects - -* libports/ports.h (struct port_info): Use the new type. -* libports/lookup-port.c: No need to lock _ports_lock anymore. -* libports/bucket-iterate.c: Likewise. -* libports/complete-deallocate.c: Check if someone reacquired a -reference through a hash table lookup. -* libports/create-internal.c: Use the new reference counting primitives. -* libports/get-right.c: Likewise. -* libports/import-port.c: Likewise. -* libports/port-deref-weak.c: Likewise. -* libports/port-deref.c: Likewise. -* libports/port-ref-weak.c: Likewise. -* libports/port-ref.c: Likewise. -* libports/reallocate-from-external.c: Likewise. -* libports/transfer-right.c: Likewise. -* utils/rpctrace.c: Likewise. ---- - libports/bucket-iterate.c | 4 +--- - libports/complete-deallocate.c | 14 ++++++++++++++ - libports/create-internal.c | 3 +-- - libports/get-right.c | 2 +- - libports/import-port.c | 3 +-- - libports/lookup-port.c | 4 +--- - libports/port-deref-weak.c | 10 +++------- - libports/port-deref.c | 34 ++++++++++++++++------------------ - libports/port-ref-weak.c | 8 +++----- - libports/port-ref.c | 8 +++----- - libports/ports.h | 4 ++-- - libports/reallocate-from-external.c | 2 +- - libports/transfer-right.c | 2 +- - utils/rpctrace.c | 10 ++++++++-- - 14 files changed, 56 insertions(+), 52 deletions(-) - -diff --git a/libports/bucket-iterate.c b/libports/bucket-iterate.c -index 88f082f..bf6857a 100644 ---- a/libports/bucket-iterate.c -+++ b/libports/bucket-iterate.c -@@ -35,7 +35,6 @@ _ports_bucket_class_iterate (struct hurd_ihash *ht, - size_t i, n, nr_items; - error_t err; - -- pthread_mutex_lock (&_ports_lock); - pthread_rwlock_rdlock (&_ports_htable_lock); - - if (ht->nr_items == 0) -@@ -59,13 +58,12 @@ _ports_bucket_class_iterate (struct hurd_ihash *ht, - - if (class == 0 || pi->class == class) - { -- pi->refcnt++; -+ refcounts_ref (&pi->refcounts, NULL); - p[n] = pi; - n++; - } - } - pthread_rwlock_unlock (&_ports_htable_lock); -- pthread_mutex_unlock (&_ports_lock); - - if (n == 0) - { -diff --git a/libports/complete-deallocate.c b/libports/complete-deallocate.c -index 4768dab..0d852f5 100644 ---- a/libports/complete-deallocate.c -+++ b/libports/complete-deallocate.c -@@ -29,15 +29,29 @@ _ports_complete_deallocate (struct port_info *pi) - - if (pi->port_right) - { -+ struct references result; -+ - pthread_rwlock_wrlock (&_ports_htable_lock); -+ refcounts_references (&pi->refcounts, &result); -+ if (result.hard > 0 || result.weak > 0) -+ { -+ /* A reference was reacquired through a hash table lookup. -+ It's fine, we didn't touch anything yet. */ -+ pthread_mutex_unlock (&_ports_htable_lock); -+ return; -+ } -+ - hurd_ihash_locp_remove (&_ports_htable, pi->ports_htable_entry); - hurd_ihash_locp_remove (&pi->bucket->htable, pi->hentry); - pthread_rwlock_unlock (&_ports_htable_lock); -+ - mach_port_mod_refs (mach_task_self (), pi->port_right, - MACH_PORT_RIGHT_RECEIVE, -1); - pi->port_right = MACH_PORT_NULL; - } - -+ pthread_mutex_lock (&_ports_lock); -+ - pi->bucket->count--; - pi->class->count--; - -diff --git a/libports/create-internal.c b/libports/create-internal.c -index 8543986..2d85931 100644 ---- a/libports/create-internal.c -+++ b/libports/create-internal.c -@@ -54,8 +54,7 @@ _ports_create_port_internal (struct port_class *class, - } - - pi->class = class; -- pi->refcnt = 1; -- pi->weakrefcnt = 0; -+ refcounts_init (&pi->refcounts, 1, 0); - pi->cancel_threshold = 0; - pi->mscount = 0; - pi->flags = 0; -diff --git a/libports/get-right.c b/libports/get-right.c -index 89050c6..8681f46 100644 ---- a/libports/get-right.c -+++ b/libports/get-right.c -@@ -41,7 +41,7 @@ ports_get_right (void *port) - if ((pi->flags & PORT_HAS_SENDRIGHTS) == 0) - { - pi->flags |= PORT_HAS_SENDRIGHTS; -- pi->refcnt++; -+ refcounts_ref (&pi->refcounts, NULL); - err = mach_port_request_notification (mach_task_self (), - pi->port_right, - MACH_NOTIFY_NO_SENDERS, -diff --git a/libports/import-port.c b/libports/import-port.c -index 2660672..c337c85 100644 ---- a/libports/import-port.c -+++ b/libports/import-port.c -@@ -48,8 +48,7 @@ ports_import_port (struct port_class *class, struct port_bucket *bucket, - return ENOMEM; - - pi->class = class; -- pi->refcnt = 1 + !!stat.mps_srights; -- pi->weakrefcnt = 0; -+ refcounts_init (&pi->refcounts, 1 + !!stat.mps_srights, 0); - pi->cancel_threshold = 0; - pi->mscount = stat.mps_mscount; - pi->flags = stat.mps_srights ? PORT_HAS_SENDRIGHTS : 0; -diff --git a/libports/lookup-port.c b/libports/lookup-port.c -index 858ee11..cff0546 100644 ---- a/libports/lookup-port.c -+++ b/libports/lookup-port.c -@@ -28,7 +28,6 @@ ports_lookup_port (struct port_bucket *bucket, - { - struct port_info *pi; - -- pthread_mutex_lock (&_ports_lock); - pthread_rwlock_rdlock (&_ports_htable_lock); - - pi = hurd_ihash_find (&_ports_htable, port); -@@ -38,10 +37,9 @@ ports_lookup_port (struct port_bucket *bucket, - pi = 0; - - if (pi) -- pi->refcnt++; -+ ports_port_ref (pi); - - pthread_rwlock_unlock (&_ports_htable_lock); -- pthread_mutex_unlock (&_ports_lock); - - return pi; - } -diff --git a/libports/port-deref-weak.c b/libports/port-deref-weak.c -index beb4842..8432660 100644 ---- a/libports/port-deref-weak.c -+++ b/libports/port-deref-weak.c -@@ -25,12 +25,8 @@ void - ports_port_deref_weak (void *portstruct) - { - struct port_info *pi = portstruct; -- -- pthread_mutex_lock (&_ports_lock); -- assert (pi->weakrefcnt); -- pi->weakrefcnt--; -- if (pi->refcnt == 0 && pi->weakrefcnt == 0) -+ struct references result; -+ refcounts_deref_weak (&pi->refcounts, &result); -+ if (result.hard == 0 && result.weak == 0) - _ports_complete_deallocate (pi); -- else -- pthread_mutex_unlock (&_ports_lock); - } -diff --git a/libports/port-deref.c b/libports/port-deref.c -index cf9b238..b97dd13 100644 ---- a/libports/port-deref.c -+++ b/libports/port-deref.c -@@ -25,26 +25,24 @@ void - ports_port_deref (void *portstruct) - { - struct port_info *pi = portstruct; -- int trieddroppingweakrefs = 0; -- -- retry: -- -- pthread_mutex_lock (&_ports_lock); -- -- if (pi->refcnt == 1 && pi->weakrefcnt -- && pi->class->dropweak_routine && !trieddroppingweakrefs) -+ struct references result; -+ -+ if (pi->class->dropweak_routine) - { -- pthread_mutex_unlock (&_ports_lock); -- (*pi->class->dropweak_routine) (pi); -- trieddroppingweakrefs = 1; -- goto retry; -+ /* If we need to call the dropweak routine, we need to hold one -+ reference while doing so. We use a weak reference for this -+ purpose, which we acquire by demoting our hard reference to a -+ weak one. */ -+ refcounts_demote (&pi->refcounts, &result); -+ -+ if (result.hard == 0 && result.weak > 1) -+ (*pi->class->dropweak_routine) (pi); -+ -+ refcounts_deref_weak (&pi->refcounts, &result); - } -- -- assert (pi->refcnt); -+ else -+ refcounts_deref (&pi->refcounts, &result); - -- pi->refcnt--; -- if (pi->refcnt == 0 && pi->weakrefcnt == 0) -+ if (result.hard == 0 && result.weak == 0) - _ports_complete_deallocate (pi); -- else -- pthread_mutex_unlock (&_ports_lock); - } -diff --git a/libports/port-ref-weak.c b/libports/port-ref-weak.c -index c7d3c69..e4b7fc8 100644 ---- a/libports/port-ref-weak.c -+++ b/libports/port-ref-weak.c -@@ -25,9 +25,7 @@ void - ports_port_ref_weak (void *portstruct) - { - struct port_info *pi = portstruct; -- -- pthread_mutex_lock (&_ports_lock); -- assert (pi->refcnt || pi->weakrefcnt); -- pi->weakrefcnt++; -- pthread_mutex_unlock (&_ports_lock); -+ struct references result; -+ refcounts_ref_weak (&pi->refcounts, &result); -+ assert (result.hard > 0 || result.weak > 1); - } -diff --git a/libports/port-ref.c b/libports/port-ref.c -index 92b7118..761c50f 100644 ---- a/libports/port-ref.c -+++ b/libports/port-ref.c -@@ -25,9 +25,7 @@ void - ports_port_ref (void *portstruct) - { - struct port_info *pi = portstruct; -- -- pthread_mutex_lock (&_ports_lock); -- assert (pi->refcnt || pi->weakrefcnt); -- pi->refcnt++; -- pthread_mutex_unlock (&_ports_lock); -+ struct references result; -+ refcounts_ref (&pi->refcounts, &result); -+ assert (result.hard > 1 || result.weak > 0); - } -diff --git a/libports/ports.h b/libports/ports.h -index 6922162..40d3b43 100644 ---- a/libports/ports.h -+++ b/libports/ports.h -@@ -27,6 +27,7 @@ - #include <hurd/ihash.h> - #include <mach/notify.h> - #include <pthread.h> -+#include <refcount.h> - - /* These are global values for common flags used in the various structures. - Not all of these are meaningful in all flag fields. */ -@@ -39,8 +40,7 @@ - struct port_info - { - struct port_class *class; -- int refcnt; -- int weakrefcnt; -+ refcounts_t refcounts; - mach_port_mscount_t mscount; - mach_msg_seqno_t cancel_threshold; - int flags; -diff --git a/libports/reallocate-from-external.c b/libports/reallocate-from-external.c -index 9944b39..7205bd9 100644 ---- a/libports/reallocate-from-external.c -+++ b/libports/reallocate-from-external.c -@@ -56,7 +56,7 @@ ports_reallocate_from_external (void *portstruct, mach_port_t receive) - else if (((pi->flags & PORT_HAS_SENDRIGHTS) == 0) && stat.mps_srights) - { - pi->flags |= PORT_HAS_SENDRIGHTS; -- pi->refcnt++; -+ refcounts_ref (&pi->refcounts, NULL); - } - - pi->port_right = receive; -diff --git a/libports/transfer-right.c b/libports/transfer-right.c -index 3f48290..776a8d2 100644 ---- a/libports/transfer-right.c -+++ b/libports/transfer-right.c -@@ -72,7 +72,7 @@ ports_transfer_right (void *tostruct, - else if (((topi->flags & PORT_HAS_SENDRIGHTS) == 0) && hassendrights) - { - topi->flags |= PORT_HAS_SENDRIGHTS; -- topi->refcnt++; -+ refcounts_ref (&topi->refcounts, NULL); - } - } - -diff --git a/utils/rpctrace.c b/utils/rpctrace.c -index fc913e3..b11fea4 100644 ---- a/utils/rpctrace.c -+++ b/utils/rpctrace.c -@@ -431,7 +431,9 @@ destroy_receiver_info (struct receiver_info *info) - while (send_wrapper) - { - struct sender_info *next = send_wrapper->next; -- assert (TRACED_INFO (send_wrapper)->pi.refcnt == 1); -+ assert ( -+ refcounts_hard_references (&TRACED_INFO (send_wrapper)->pi.refcounts) -+ == 1); - /* Reset the receive_right of the send wrapper in advance to avoid - * destroy_receiver_info is called when the port info is destroyed. */ - send_wrapper->receive_right = NULL; -@@ -848,7 +850,11 @@ rewrite_right (mach_port_t *right, mach_msg_type_name_t *type, - hurd_ihash_locp_remove (&traced_names, receiver_info->locp); - - send_wrapper2 = get_send_wrapper (receiver_info, dest, &rr); -- assert (TRACED_INFO (send_wrapper2)->pi.refcnt == 1); -+ assert ( -+ refcounts_hard_references ( -+ &TRACED_INFO (send_wrapper2)->pi.refcounts) -+ == 1); -+ - name = TRACED_INFO (send_wrapper2)->name; - TRACED_INFO (send_wrapper2)->name = NULL; - /* send_wrapper2 isn't destroyed normally, so we need to unlink --- -2.0.0.rc2 - diff --git a/debian/patches/0004-ext2fs-use-a-seperate-lock-to-protect-nodehash.patch b/debian/patches/0004-ext2fs-use-a-seperate-lock-to-protect-nodehash.patch deleted file mode 100644 index b92ac2f8..00000000 --- a/debian/patches/0004-ext2fs-use-a-seperate-lock-to-protect-nodehash.patch +++ /dev/null @@ -1,210 +0,0 @@ -From c622462a48e26c35c1faafb03bfd2755b818106a Mon Sep 17 00:00:00 2001 -From: Justus Winter <4winter@informatik.uni-hamburg.de> -Date: Tue, 13 May 2014 13:09:15 +0200 -Subject: [PATCH 4/8] ext2fs: use a seperate lock to protect nodehash - -Previously, ext2fs used diskfs_node_refcnt_lock to serialize access to -the nodehash. - -Use a separate lock to protect nodehash. Adjust the reference -counting accordingly. Every node in the nodehash carries a light -reference. When we are asked to give up that light reference, we -reacquire our lock momentarily to check whether someone else -reacquired a reference through the nodehash. - -* ext2fs/inode.c (nodecache_lock): New lock. -(diskfs_cached_lookup): Use a separate lock to protect nodehash. -Adjust the reference counting accordingly. -(ifind): Likewise. -(diskfs_node_iterate): Likewise. -(diskfs_node_norefs): Move the code removing the node from nodehash... -(diskfs_try_dropping_softrefs): ... here, where we check whether -someone reacquired a reference, and if so hold on to our light -reference. ---- - ext2fs/inode.c | 76 ++++++++++++++++++++++++++++++++++++++++------------------ - 1 file changed, 53 insertions(+), 23 deletions(-) - -diff --git a/ext2fs/inode.c b/ext2fs/inode.c -index ed78265..0b3fa8b 100644 ---- a/ext2fs/inode.c -+++ b/ext2fs/inode.c -@@ -46,8 +46,18 @@ - #define INOHASH(ino) (((unsigned)(ino))%INOHSZ) - #endif - -+/* The nodehash is a cache of nodes. -+ -+ Access to nodehash and nodehash_nr_items is protected by -+ nodecache_lock. -+ -+ Every node in the nodehash carries a light reference. When we are -+ asked to give up that light reference, we reacquire our lock -+ momentarily to check whether someone else reacquired a reference -+ through the nodehash. */ - static struct node *nodehash[INOHSZ]; - static size_t nodehash_nr_items; -+static pthread_rwlock_t nodecache_lock = PTHREAD_RWLOCK_INITIALIZER; - - static error_t read_node (struct node *np); - -@@ -71,24 +81,22 @@ diskfs_cached_lookup (ino_t inum, struct node **npp) - struct node *np; - struct disknode *dn; - -- pthread_spin_lock (&diskfs_node_refcnt_lock); -+ pthread_rwlock_rdlock (&nodecache_lock); - for (np = nodehash[INOHASH(inum)]; np; np = np->dn->hnext) - if (np->cache_id == inum) - { -- np->references++; -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -+ diskfs_nref (np); -+ pthread_rwlock_unlock (&nodecache_lock); - pthread_mutex_lock (&np->lock); - *npp = np; - return 0; - } -+ pthread_rwlock_unlock (&nodecache_lock); - - /* Format specific data for the new node. */ - dn = malloc (sizeof (struct disknode)); - if (! dn) -- { -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -- return ENOMEM; -- } -+ return ENOMEM; - dn->dirents = 0; - dn->dir_idx = 0; - dn->pager = 0; -@@ -102,14 +110,15 @@ diskfs_cached_lookup (ino_t inum, struct node **npp) - pthread_mutex_lock (&np->lock); - - /* Put NP in NODEHASH. */ -+ pthread_rwlock_wrlock (&nodecache_lock); - dn->hnext = nodehash[INOHASH(inum)]; - if (dn->hnext) - dn->hnext->dn->hprevp = &dn->hnext; - dn->hprevp = &nodehash[INOHASH(inum)]; - nodehash[INOHASH(inum)] = np; -+ diskfs_nref_light (np); - nodehash_nr_items += 1; -- -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -+ pthread_rwlock_unlock (&nodecache_lock); - - /* Get the contents of NP off disk. */ - err = read_node (np); -@@ -140,14 +149,13 @@ ifind (ino_t inum) - { - struct node *np; - -- pthread_spin_lock (&diskfs_node_refcnt_lock); -+ pthread_rwlock_rdlock (&nodecache_lock); - for (np = nodehash[INOHASH(inum)]; np; np = np->dn->hnext) - { - if (np->cache_id != inum) - continue; - -- assert (np->references); -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -+ pthread_rwlock_unlock (&nodecache_lock); - return np; - } - assert (0); -@@ -158,11 +166,6 @@ ifind (ino_t inum) - void - diskfs_node_norefs (struct node *np) - { -- *np->dn->hprevp = np->dn->hnext; -- if (np->dn->hnext) -- np->dn->hnext->dn->hprevp = np->dn->hprevp; -- nodehash_nr_items -= 1; -- - if (np->dn->dirents) - free (np->dn->dirents); - assert (!np->dn->pager); -@@ -180,6 +183,33 @@ diskfs_node_norefs (struct node *np) - void - diskfs_try_dropping_softrefs (struct node *np) - { -+ pthread_rwlock_wrlock (&nodecache_lock); -+ if (np->dn->hnext != NULL) -+ { -+ /* Check if someone reacquired a reference through the -+ nodehash. */ -+ unsigned int references; -+ pthread_spin_lock (&diskfs_node_refcnt_lock); -+ references = np->references; -+ pthread_spin_unlock (&diskfs_node_refcnt_lock); -+ -+ if (references > 0) -+ { -+ /* A reference was reacquired through a hash table lookup. -+ It's fine, we didn't touch anything yet. */ -+ pthread_rwlock_unlock (&nodecache_lock); -+ return; -+ } -+ -+ *np->dn->hprevp = np->dn->hnext; -+ if (np->dn->hnext) -+ np->dn->hnext->dn->hprevp = np->dn->hprevp; -+ np->dn->hnext = NULL; -+ nodehash_nr_items -= 1; -+ diskfs_nrele_light (np); -+ } -+ pthread_rwlock_unlock (&nodecache_lock); -+ - drop_pager_softrefs (np); - } - -@@ -556,12 +586,12 @@ diskfs_node_iterate (error_t (*fun)(struct node *)) - size_t num_nodes; - struct node *node, **node_list, **p; - -- pthread_spin_lock (&diskfs_node_refcnt_lock); -+ pthread_rwlock_rdlock (&nodecache_lock); - - /* We must copy everything from the hash table into another data structure - to avoid running into any problems with the hash-table being modified - during processing (normally we delegate access to hash-table with -- diskfs_node_refcnt_lock, but we can't hold this while locking the -+ nodecache_lock, but we can't hold this while locking the - individual node locks). */ - num_nodes = nodehash_nr_items; - -@@ -570,7 +600,7 @@ diskfs_node_iterate (error_t (*fun)(struct node *)) - node_list = malloc (num_nodes * sizeof (struct node *)); - if (node_list == NULL) - { -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -+ pthread_rwlock_unlock (&nodecache_lock); - ext2_debug ("unable to allocate temporary node table"); - return ENOMEM; - } -@@ -580,10 +610,10 @@ diskfs_node_iterate (error_t (*fun)(struct node *)) - for (node = nodehash[n]; node; node = node->dn->hnext) - { - *p++ = node; -- node->references++; -+ diskfs_nref_light (node); - } - -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -+ pthread_rwlock_unlock (&nodecache_lock); - - p = node_list; - while (num_nodes-- > 0) -@@ -595,7 +625,7 @@ diskfs_node_iterate (error_t (*fun)(struct node *)) - err = (*fun)(node); - pthread_mutex_unlock (&node->lock); - } -- diskfs_nrele (node); -+ diskfs_nrele_light (node); - } - - free (node_list); --- -2.0.0.rc2 - diff --git a/debian/patches/0005-fatfs-use-a-seperate-lock-to-protect-nodehash.patch b/debian/patches/0005-fatfs-use-a-seperate-lock-to-protect-nodehash.patch deleted file mode 100644 index fe868f84..00000000 --- a/debian/patches/0005-fatfs-use-a-seperate-lock-to-protect-nodehash.patch +++ /dev/null @@ -1,253 +0,0 @@ -From b3ddda348965fa6f8ad6cdf839d8f6a225e1070f Mon Sep 17 00:00:00 2001 -From: Justus Winter <4winter@informatik.uni-hamburg.de> -Date: Tue, 13 May 2014 15:14:53 +0200 -Subject: [PATCH 5/8] fatfs: use a seperate lock to protect nodehash - -Previously, fatfs used diskfs_node_refcnt_lock to serialize access to -the nodehash. - -Use a separate lock to protect nodehash. Adjust the reference -counting accordingly. Every node in the nodehash carries a light -reference. When we are asked to give up that light reference, we -reacquire our lock momentarily to check whether someone else -reacquired a reference through the nodehash. - -* fatfs/inode.c (nodecache_lock): New lock. -(diskfs_cached_lookup): Use a separate lock to protect nodehash. -Adjust the reference counting accordingly. -(ifind): Likewise. -(diskfs_node_iterate): Likewise. -(diskfs_node_norefs): Move the code removing the node from nodehash... -(diskfs_try_dropping_softrefs): ... here, where we check whether -someone reacquired a reference, and if so hold on to our light -reference. ---- - fatfs/inode.c | 93 +++++++++++++++++++++++++++++++++++++++-------------------- - 1 file changed, 62 insertions(+), 31 deletions(-) - -diff --git a/fatfs/inode.c b/fatfs/inode.c -index ed6f3f0..1e5abdf 100644 ---- a/fatfs/inode.c -+++ b/fatfs/inode.c -@@ -44,8 +44,18 @@ - #define INOHASH(ino) (((unsigned)(ino))%INOHSZ) - #endif - -+/* The nodehash is a cache of nodes. -+ -+ Access to nodehash and nodehash_nr_items is protected by -+ nodecache_lock. -+ -+ Every node in the nodehash carries a light reference. When we are -+ asked to give up that light reference, we reacquire our lock -+ momentarily to check whether someone else reacquired a reference -+ through the nodehash. */ - static struct node *nodehash[INOHSZ]; - static size_t nodehash_nr_items; -+static pthread_rwlock_t nodecache_lock = PTHREAD_RWLOCK_INITIALIZER; - - static error_t read_node (struct node *np, vm_address_t buf); - -@@ -67,24 +77,23 @@ diskfs_cached_lookup (ino64_t inum, struct node **npp) - struct node *np; - struct disknode *dn; - -- pthread_spin_lock (&diskfs_node_refcnt_lock); -+ pthread_rwlock_rdlock (&nodecache_lock); - for (np = nodehash[INOHASH(inum)]; np; np = np->dn->hnext) - if (np->cache_id == inum) - { -- np->references++; -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -+ diskfs_nref (np); -+ pthread_rwlock_unlock (&nodecache_lock); - pthread_mutex_lock (&np->lock); - *npp = np; - return 0; - } -+ pthread_rwlock_unlock (&nodecache_lock); - - /* Format specific data for the new node. */ - dn = malloc (sizeof (struct disknode)); - if (! dn) -- { -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -- return ENOMEM; -- } -+ return ENOMEM; -+ - dn->pager = 0; - dn->first = 0; - dn->last = 0; -@@ -102,15 +111,16 @@ diskfs_cached_lookup (ino64_t inum, struct node **npp) - pthread_mutex_lock (&np->lock); - - /* Put NP in NODEHASH. */ -+ pthread_rwlock_wrlock (&nodecache_lock); - dn->hnext = nodehash[INOHASH(inum)]; - if (dn->hnext) - dn->hnext->dn->hprevp = &dn->hnext; - dn->hprevp = &nodehash[INOHASH(inum)]; - nodehash[INOHASH(inum)] = np; -+ diskfs_nref_light (np); - nodehash_nr_items += 1; -+ pthread_rwlock_unlock (&nodecache_lock); - -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -- - /* Get the contents of NP off disk. */ - err = read_node (np, 0); - -@@ -133,24 +143,23 @@ diskfs_cached_lookup_in_dirbuf (int inum, struct node **npp, vm_address_t buf) - struct node *np; - struct disknode *dn; - -- pthread_spin_lock (&diskfs_node_refcnt_lock); -+ pthread_rwlock_rdlock (&nodecache_lock); - for (np = nodehash[INOHASH(inum)]; np; np = np->dn->hnext) - if (np->cache_id == inum) - { -- np->references++; -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -+ diskfs_nref (np); -+ pthread_rwlock_unlock (&nodecache_lock); - pthread_mutex_lock (&np->lock); - *npp = np; - return 0; - } -+ pthread_rwlock_unlock (&nodecache_lock); - - /* Format specific data for the new node. */ - dn = malloc (sizeof (struct disknode)); - if (! dn) -- { -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -- return ENOMEM; -- } -+ return ENOMEM; -+ - dn->pager = 0; - dn->first = 0; - dn->last = 0; -@@ -168,15 +177,16 @@ diskfs_cached_lookup_in_dirbuf (int inum, struct node **npp, vm_address_t buf) - pthread_mutex_lock (&np->lock); - - /* Put NP in NODEHASH. */ -+ pthread_rwlock_wrlock (&nodecache_lock); - dn->hnext = nodehash[INOHASH(inum)]; - if (dn->hnext) - dn->hnext->dn->hprevp = &dn->hnext; - dn->hprevp = &nodehash[INOHASH(inum)]; - nodehash[INOHASH(inum)] = np; -+ diskfs_nref_light (np); - nodehash_nr_items += 1; -+ pthread_rwlock_unlock (&nodecache_lock); - -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -- - /* Get the contents of NP off disk. */ - err = read_node (np, buf); - -@@ -196,14 +206,13 @@ ifind (ino_t inum) - { - struct node *np; - -- pthread_spin_lock (&diskfs_node_refcnt_lock); -+ pthread_rwlock_rdlock (&nodecache_lock); - for (np = nodehash[INOHASH(inum)]; np; np = np->dn->hnext) - { - if (np->cache_id != inum) - continue; - -- assert (np->references); -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -+ pthread_rwlock_unlock (&nodecache_lock); - return np; - } - assert (0); -@@ -216,11 +225,6 @@ diskfs_node_norefs (struct node *np) - { - struct cluster_chain *last = np->dn->first; - -- *np->dn->hprevp = np->dn->hnext; -- if (np->dn->hnext) -- np->dn->hnext->dn->hprevp = np->dn->hprevp; -- nodehash_nr_items -= 1; -- - while (last) - { - struct cluster_chain *next = last->next; -@@ -251,6 +255,33 @@ diskfs_node_norefs (struct node *np) - void - diskfs_try_dropping_softrefs (struct node *np) - { -+ pthread_rwlock_wrlock (&nodecache_lock); -+ if (np->dn->hnext != NULL) -+ { -+ /* Check if someone reacquired a reference through the -+ nodehash. */ -+ unsigned int references; -+ pthread_spin_lock (&diskfs_node_refcnt_lock); -+ references = np->references; -+ pthread_spin_unlock (&diskfs_node_refcnt_lock); -+ -+ if (references > 0) -+ { -+ /* A reference was reacquired through a hash table lookup. -+ It's fine, we didn't touch anything yet. */ -+ pthread_rwlock_unlock (&nodecache_lock); -+ return; -+ } -+ -+ *np->dn->hprevp = np->dn->hnext; -+ if (np->dn->hnext) -+ np->dn->hnext->dn->hprevp = np->dn->hprevp; -+ np->dn->hnext = NULL; -+ nodehash_nr_items -= 1; -+ diskfs_nrele_light (np); -+ } -+ pthread_rwlock_unlock (&nodecache_lock); -+ - drop_pager_softrefs (np); - } - -@@ -554,12 +585,12 @@ diskfs_node_iterate (error_t (*fun)(struct node *)) - size_t num_nodes; - struct node *node, **node_list, **p; - -- pthread_spin_lock (&diskfs_node_refcnt_lock); -+ pthread_rwlock_rdlock (&nodecache_lock); - - /* We must copy everything from the hash table into another data structure - to avoid running into any problems with the hash-table being modified - during processing (normally we delegate access to hash-table with -- diskfs_node_refcnt_lock, but we can't hold this while locking the -+ nodecache_lock, but we can't hold this while locking the - individual node locks). */ - - num_nodes = nodehash_nr_items; -@@ -570,10 +601,10 @@ diskfs_node_iterate (error_t (*fun)(struct node *)) - for (node = nodehash[n]; node; node = node->dn->hnext) - { - *p++ = node; -- node->references++; -+ diskfs_nref_light (node); - } - -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -+ pthread_rwlock_unlock (&nodecache_lock); - - p = node_list; - while (num_nodes-- > 0) -@@ -585,7 +616,7 @@ diskfs_node_iterate (error_t (*fun)(struct node *)) - err = (*fun)(node); - pthread_mutex_unlock (&node->lock); - } -- diskfs_nrele (node); -+ diskfs_nrele_light (node); - } - - return err; --- -2.0.0.rc2 - diff --git a/debian/patches/0006-isofs-use-a-seperate-lock-to-protect-node_cache.patch b/debian/patches/0006-isofs-use-a-seperate-lock-to-protect-node_cache.patch deleted file mode 100644 index 97774dd1..00000000 --- a/debian/patches/0006-isofs-use-a-seperate-lock-to-protect-node_cache.patch +++ /dev/null @@ -1,229 +0,0 @@ -From 716241f173049ef185466472d625c771e911b489 Mon Sep 17 00:00:00 2001 -From: Justus Winter <4winter@informatik.uni-hamburg.de> -Date: Tue, 13 May 2014 15:16:31 +0200 -Subject: [PATCH 6/8] isofs: use a seperate lock to protect node_cache - -Previously, isofs used diskfs_node_refcnt_lock to serialize access to -the node_cache. - -Use a separate lock to protect node_cache. Adjust the reference -counting accordingly. Every node in the node_cache carries a light -reference. When we are asked to give up that light reference, we -reacquire our lock momentarily to check whether someone else -reacquired a reference through the node_cache. - -* isofs/inode.c (nodecache_lock): New lock. -(inode_cache_find): Use a separate lock to protect node_cache. -Adjust the reference counting accordingly. -(diskfs_cached_lookup): Likewise. -(load_inode): Likewise. -(cache_inode): Update comment accordingly. -(diskfs_node_iterate): Likewise. -(diskfs_node_norefs): Move the code removing the node from node_cache... -(diskfs_try_dropping_softrefs): ... here, where we check whether -someone reacquired a reference, and if so hold on to our light -reference. ---- - isofs/inode.c | 81 +++++++++++++++++++++++++++++++++++++++++------------------ - 1 file changed, 56 insertions(+), 25 deletions(-) - -diff --git a/isofs/inode.c b/isofs/inode.c -index cdc05ae..ec874df 100644 ---- a/isofs/inode.c -+++ b/isofs/inode.c -@@ -48,9 +48,19 @@ struct node_cache - struct node *np; /* if live */ - }; - -+/* The node_cache is a cache of nodes. -+ -+ Access to node_cache, node_cache_size, and node_cache_alloced is -+ protected by nodecache_lock. -+ -+ Every node in the node_cache carries a light reference. When we -+ are asked to give up that light reference, we reacquire our lock -+ momentarily to check whether someone else reacquired a reference -+ through the node_cache. */ - static int node_cache_size = 0; - static int node_cache_alloced = 0; - struct node_cache *node_cache = 0; -+static pthread_rwlock_t nodecache_lock = PTHREAD_RWLOCK_INITIALIZER; - - /* Forward */ - static error_t read_disknode (struct node *, -@@ -58,7 +68,7 @@ static error_t read_disknode (struct node *, - - - /* See if node with identifier ID is in the cache. If so, return it, -- with one additional reference. diskfs_node_refcnt_lock must be held -+ with one additional reference. nodecache_lock must be held - on entry to the call, and will be released iff the node was found - in the cache. */ - void -@@ -71,8 +81,8 @@ inode_cache_find (off_t id, struct node **npp) - && node_cache[i].np) - { - *npp = node_cache[i].np; -- (*npp)->references++; -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -+ diskfs_nref (*npp); -+ pthread_rwlock_unlock (&nodecache_lock); - pthread_mutex_lock (&(*npp)->lock); - return; - } -@@ -92,7 +102,7 @@ use_file_start_id (struct dirrect *record, struct rrip_lookup *rr) - } - - /* Enter NP into the cache. The directory entry we used is DR, the -- cached Rock-Ridge info RR. diskfs_node_refcnt_lock must be held. */ -+ cached Rock-Ridge info RR. nodecache_lock must be held. */ - void - cache_inode (struct node *np, struct dirrect *record, - struct rrip_lookup *rr) -@@ -155,7 +165,7 @@ diskfs_cached_lookup (ino_t id, struct node **npp) - to avoid presenting zero cache ID's. */ - id--; - -- pthread_spin_lock (&diskfs_node_refcnt_lock); -+ pthread_rwlock_rdlock (&nodecache_lock); - assert (id < node_cache_size); - - np = node_cache[id].np; -@@ -174,7 +184,7 @@ diskfs_cached_lookup (ino_t id, struct node **npp) - dn = malloc (sizeof (struct disknode)); - if (!dn) - { -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -+ pthread_rwlock_unlock (&nodecache_lock); - release_rrip (&rr); - return ENOMEM; - } -@@ -185,16 +195,17 @@ diskfs_cached_lookup (ino_t id, struct node **npp) - if (!np) - { - free (dn); -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -+ pthread_rwlock_unlock (&nodecache_lock); - release_rrip (&rr); - return ENOMEM; - } - np->cache_id = id + 1; /* see above for rationale for increment */ - pthread_mutex_lock (&np->lock); - c->np = np; -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -+ diskfs_nref_light (np); -+ pthread_rwlock_unlock (&nodecache_lock); - -- err = read_disknode (np, node_cache[id].dr, &rr); -+ err = read_disknode (np, dn->dr, &rr); - if (!err) - *npp = np; - -@@ -204,8 +215,8 @@ diskfs_cached_lookup (ino_t id, struct node **npp) - } - - -- np->references++; -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -+ diskfs_nref (np); -+ pthread_rwlock_unlock (&nodecache_lock); - pthread_mutex_lock (&np->lock); - *npp = np; - return 0; -@@ -315,7 +326,7 @@ load_inode (struct node **npp, struct dirrect *record, - if (rr->valid & VALID_CL) - record = rr->realdirent; - -- pthread_spin_lock (&diskfs_node_refcnt_lock); -+ pthread_rwlock_rdlock (&nodecache_lock); - - /* First check the cache */ - if (use_file_start_id (record, rr)) -@@ -323,19 +334,16 @@ load_inode (struct node **npp, struct dirrect *record, - else - inode_cache_find ((off_t) ((void *) record - (void *) disk_image), npp); - -+ pthread_rwlock_unlock (&nodecache_lock); -+ - if (*npp) -- { -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -- return 0; -- } -+ return 0; - - /* Create a new node */ - dn = malloc (sizeof (struct disknode)); - if (!dn) -- { -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -- return ENOMEM; -- } -+ return ENOMEM; -+ - dn->fileinfo = 0; - dn->dr = record; - dn->file_start = file_start; -@@ -344,14 +352,14 @@ load_inode (struct node **npp, struct dirrect *record, - if (!np) - { - free (dn); -- pthread_spin_unlock (&diskfs_node_refcnt_lock); - return ENOMEM; - } - - pthread_mutex_lock (&np->lock); - -+ pthread_rwlock_wrlock (&nodecache_lock); - cache_inode (np, record, rr); -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -+ pthread_rwlock_unlock (&nodecache_lock); - - err = read_disknode (np, record, rr); - *npp = np; -@@ -505,9 +513,6 @@ error_t (*diskfs_read_symlink_hook) (struct node *, char *) - void - diskfs_node_norefs (struct node *np) - { -- assert (node_cache[np->cache_id - 1].np == np); -- node_cache[np->cache_id - 1].np = 0; -- - if (np->dn->translator) - free (np->dn->translator); - -@@ -521,6 +526,32 @@ diskfs_node_norefs (struct node *np) - void - diskfs_try_dropping_softrefs (struct node *np) - { -+ pthread_rwlock_wrlock (&nodecache_lock); -+ if (np->cache_id != 0) -+ { -+ assert (node_cache[np->cache_id - 1].np == np); -+ -+ /* Check if someone reacquired a reference through the -+ node_cache. */ -+ unsigned int references; -+ pthread_spin_lock (&diskfs_node_refcnt_lock); -+ references = np->references; -+ pthread_spin_unlock (&diskfs_node_refcnt_lock); -+ -+ if (references > 0) -+ { -+ /* A reference was reacquired through a hash table lookup. -+ It's fine, we didn't touch anything yet. */ -+ pthread_rwlock_unlock (&nodecache_lock); -+ return; -+ } -+ -+ node_cache[np->cache_id - 1].np = 0; -+ np->cache_id = 0; -+ diskfs_nrele_light (np); -+ } -+ pthread_rwlock_unlock (&nodecache_lock); -+ - drop_pager_softrefs (np); - } - --- -2.0.0.rc2 - diff --git a/debian/patches/0007-tmpfs-use-a-seperate-lock-to-protect-all_nodes.patch b/debian/patches/0007-tmpfs-use-a-seperate-lock-to-protect-all_nodes.patch deleted file mode 100644 index ac54f105..00000000 --- a/debian/patches/0007-tmpfs-use-a-seperate-lock-to-protect-all_nodes.patch +++ /dev/null @@ -1,293 +0,0 @@ -From 10a755611772880b869237feb0bac4b360817a79 Mon Sep 17 00:00:00 2001 -From: Justus Winter <4winter@informatik.uni-hamburg.de> -Date: Tue, 13 May 2014 15:35:42 +0200 -Subject: [PATCH 7/8] tmpfs: use a seperate lock to protect all_nodes - -Previously, tmpfs used diskfs_node_refcnt_lock to serialize access to -the all_nodes and some other related global state related to memory -consumption. - -Use a separate lock to protect all_nodes, and atomic operations to -access the state related to memory consumption. Adjust the reference -counting accordingly. Every node in the all_nodes carries a light -reference. When we are asked to give up that light reference, we -reacquire our lock momentarily to check whether someone else -reacquired a reference through the all_nodes. - -* tmpfs/tmpfs.h (num_files, tmpfs_space_used): Use atomic operations -for these variables. -(adjust_used): Use atomic operations. -(get_used): New convenience function to atomically retrieve -tmpfs_space_used. -* tmpfs/node.c (all_nodes_lock): New lock. -(diskfs_alloc_node): Use a separate lock to protect all_nodes. -Adjust the reference counting accordingly. -(diskfs_free_node): Likewise. -(diskfs_cached_lookup):Likewise. -(diskfs_node_iterate): Likewise. -(diskfs_node_norefs): Move the code removing the node from all_nodes... -(diskfs_try_dropping_softrefs): ... here, where we check whether -someone reacquired a reference, and if so hold on to our light -reference. -(diskfs_grow): Use atomic operations. -* tmpfs/tmpfs.c (diskfs_set_statfs): Likewise. ---- - tmpfs/node.c | 83 ++++++++++++++++++++++++++++++++++++++++------------------- - tmpfs/tmpfs.c | 6 ++--- - tmpfs/tmpfs.h | 20 +++++++++----- - 3 files changed, 73 insertions(+), 36 deletions(-) - -diff --git a/tmpfs/node.c b/tmpfs/node.c -index acc029a..e126437 100644 ---- a/tmpfs/node.c -+++ b/tmpfs/node.c -@@ -29,8 +29,18 @@ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ - unsigned int num_files; - static unsigned int gen; - -+/* all_nodes is a cache of nodes. -+ -+ Access to all_nodes and all_nodes_nr_items is protected by -+ all_nodes_lock. -+ -+ Every node in the all_nodes carries a light reference. When we are -+ asked to give up that light reference, we reacquire our lock -+ momentarily to check whether someone else reacquired a reference -+ through the all_nodes. */ - struct node *all_nodes; - static size_t all_nodes_nr_items; -+pthread_rwlock_t all_nodes_lock = PTHREAD_RWLOCK_INITIALIZER; - - error_t - diskfs_alloc_node (struct node *dp, mode_t mode, struct node **npp) -@@ -40,18 +50,17 @@ diskfs_alloc_node (struct node *dp, mode_t mode, struct node **npp) - dn = calloc (1, sizeof *dn); - if (dn == 0) - return ENOSPC; -- pthread_spin_lock (&diskfs_node_refcnt_lock); -- if (round_page (tmpfs_space_used + sizeof *dn) / vm_page_size -+ -+ if (round_page (get_used () + sizeof *dn) / vm_page_size - > tmpfs_page_limit) - { -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -+ pthread_rwlock_unlock (&all_nodes_lock); - free (dn); - return ENOSPC; - } - dn->gen = gen++; -- ++num_files; -- tmpfs_space_used += sizeof *dn; -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -+ __atomic_add_fetch (&num_files, 1, __ATOMIC_RELAXED); -+ adjust_used (sizeof *dn); - - dn->type = IFTODT (mode & S_IFMT); - return diskfs_cached_lookup ((ino_t) (uintptr_t) dn, npp); -@@ -75,15 +84,19 @@ diskfs_free_node (struct node *np, mode_t mode) - free (np->dn->u.lnk); - break; - } -+ -+ pthread_rwlock_wrlock (&all_nodes_lock); - *np->dn->hprevp = np->dn->hnext; - if (np->dn->hnext != 0) - np->dn->hnext->dn->hprevp = np->dn->hprevp; - all_nodes_nr_items -= 1; -+ pthread_rwlock_unlock (&all_nodes_lock); -+ -+ __atomic_sub_fetch (&num_files, 1, __ATOMIC_RELAXED); -+ adjust_used (-sizeof *np->dn); -+ - free (np->dn); - np->dn = 0; -- -- --num_files; -- tmpfs_space_used -= sizeof *np->dn; - } - - void -@@ -117,14 +130,6 @@ diskfs_node_norefs (struct node *np) - np->dn->u.chr = np->dn_stat.st_rdev; - break; - } -- -- /* Remove this node from the cache list rooted at `all_nodes'. */ -- *np->dn->hprevp = np->dn->hnext; -- if (np->dn->hnext != 0) -- np->dn->hnext->dn->hprevp = np->dn->hprevp; -- all_nodes_nr_items -= 1; -- np->dn->hnext = 0; -- np->dn->hprevp = 0; - } - - free (np); -@@ -167,30 +172,33 @@ diskfs_cached_lookup (ino_t inum, struct node **npp) - - assert (npp); - -+ pthread_rwlock_rdlock (&all_nodes_lock); - if (dn->hprevp != 0) /* There is already a node. */ - { - np = *dn->hprevp; - assert (np->dn == dn); - assert (*dn->hprevp == np); -- - diskfs_nref (np); -+ pthread_rwlock_unlock (&all_nodes_lock); - } - else - /* Create the new node. */ - { - struct stat *st; -+ pthread_rwlock_unlock (&all_nodes_lock); - - np = diskfs_make_node (dn); - np->cache_id = (ino_t) (uintptr_t) dn; - -- pthread_spin_lock (&diskfs_node_refcnt_lock); -+ pthread_rwlock_wrlock (&all_nodes_lock); - dn->hnext = all_nodes; - if (dn->hnext) - dn->hnext->dn->hprevp = &dn->hnext; - dn->hprevp = &all_nodes; - all_nodes = np; - all_nodes_nr_items += 1; -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -+ diskfs_nref_light (np); -+ pthread_rwlock_unlock (&all_nodes_lock); - - st = &np->dn_stat; - memset (st, 0, sizeof *st); -@@ -229,12 +237,12 @@ diskfs_node_iterate (error_t (*fun) (struct node *)) - size_t num_nodes; - struct node *node, **node_list, **p; - -- pthread_spin_lock (&diskfs_node_refcnt_lock); -+ pthread_rwlock_rdlock (&all_nodes_lock); - - /* We must copy everything from the hash table into another data structure - to avoid running into any problems with the hash-table being modified - during processing (normally we delegate access to hash-table with -- diskfs_node_refcnt_lock, but we can't hold this while locking the -+ all_nodes_lock, but we can't hold this while locking the - individual node locks). */ - - num_nodes = all_nodes_nr_items; -@@ -243,10 +251,10 @@ diskfs_node_iterate (error_t (*fun) (struct node *)) - for (node = all_nodes; node != 0; node = node->dn->hnext) - { - *p++ = node; -- node->references++; -+ diskfs_nref_light (node); - } - -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -+ pthread_rwlock_unlock (&all_nodes_lock); - - p = node_list; - while (num_nodes-- > 0) -@@ -258,7 +266,7 @@ diskfs_node_iterate (error_t (*fun) (struct node *)) - err = (*fun) (node); - pthread_mutex_unlock (&node->lock); - } -- diskfs_nrele (node); -+ diskfs_nrele_light (node); - } - - return err; -@@ -272,6 +280,29 @@ diskfs_node_iterate (error_t (*fun) (struct node *)) - void - diskfs_try_dropping_softrefs (struct node *np) - { -+ pthread_rwlock_wrlock (&all_nodes_lock); -+ if (np->cache_id != 0) -+ { -+ /* Check if someone reacquired a reference. */ -+ unsigned int references; -+ pthread_spin_lock (&diskfs_node_refcnt_lock); -+ references = np->references; -+ pthread_spin_unlock (&diskfs_node_refcnt_lock); -+ -+ if (references > 0) -+ { -+ /* A reference was reacquired. It's fine, we didn't touch -+ anything yet. */ -+ pthread_rwlock_unlock (&all_nodes_lock); -+ return; -+ } -+ -+ /* Just let go of the weak reference. The node will be removed -+ from all_nodes in diskfs_free_node. */ -+ np->cache_id = 0; -+ diskfs_nrele_light (np); -+ } -+ pthread_rwlock_unlock (&all_nodes_lock); - } - - /* The user must define this funcction. Node NP has some light -@@ -447,7 +478,7 @@ diskfs_grow (struct node *np, off_t size, struct protid *cred) - - off_t set_size = size; - size = round_page (size); -- if (round_page (tmpfs_space_used + size - np->allocsize) -+ if (round_page (get_used () + size - np->allocsize) - / vm_page_size > tmpfs_page_limit) - return ENOSPC; - -diff --git a/tmpfs/tmpfs.c b/tmpfs/tmpfs.c -index 718c6d8..0aace25 100644 ---- a/tmpfs/tmpfs.c -+++ b/tmpfs/tmpfs.c -@@ -67,10 +67,8 @@ diskfs_set_statfs (struct statfs *st) - st->f_bsize = vm_page_size; - st->f_blocks = tmpfs_page_limit; - -- pthread_spin_lock (&diskfs_node_refcnt_lock); -- st->f_files = num_files; -- pages = round_page (tmpfs_space_used) / vm_page_size; -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -+ st->f_files = __atomic_load_n (&num_files, __ATOMIC_RELAXED); -+ pages = round_page (get_used ()) / vm_page_size; - - st->f_bfree = pages < tmpfs_page_limit ? tmpfs_page_limit - pages : 0; - st->f_bavail = st->f_bfree; -diff --git a/tmpfs/tmpfs.h b/tmpfs/tmpfs.h -index b3c636d..ad47200 100644 ---- a/tmpfs/tmpfs.h -+++ b/tmpfs/tmpfs.h -@@ -69,17 +69,25 @@ struct tmpfs_dirent - char name[0]; - }; - --extern unsigned int num_files; --extern off_t tmpfs_page_limit, tmpfs_space_used; -- -+extern off_t tmpfs_page_limit; - extern mach_port_t default_pager; - -+/* These two must be accessed using atomic operations. */ -+extern unsigned int num_files; -+extern off_t tmpfs_space_used; -+ -+/* Convenience function to adjust tmpfs_space_used. */ - static inline void - adjust_used (off_t change) - { -- pthread_spin_lock (&diskfs_node_refcnt_lock); -- tmpfs_space_used += change; -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -+ __atomic_add_fetch (&num_files, change, __ATOMIC_RELAXED); -+} -+ -+/* Convenience function to get tmpfs_space_used. */ -+static inline off_t -+get_used (void) -+{ -+ return __atomic_load_n (&num_files, __ATOMIC_RELAXED); - } - - #endif --- -2.0.0.rc2 - diff --git a/debian/patches/0008-libdiskfs-lock-less-reference-counting-of-nodes.patch b/debian/patches/0008-libdiskfs-lock-less-reference-counting-of-nodes.patch deleted file mode 100644 index edfbcc43..00000000 --- a/debian/patches/0008-libdiskfs-lock-less-reference-counting-of-nodes.patch +++ /dev/null @@ -1,548 +0,0 @@ -From d030e37416f76b19a8e5e42d757c06e1926c6f91 Mon Sep 17 00:00:00 2001 -From: Justus Winter <4winter@informatik.uni-hamburg.de> -Date: Wed, 14 May 2014 11:19:35 +0200 -Subject: [PATCH 8/8] libdiskfs: lock-less reference counting of nodes - -* libdiskfs/diskfs.h (struct node): Use refcounts_t for reference counting. -(diskfs_node_refcnt_lock): Remove. -(diskfs_node_norefs,diskfs_drop_node): Change comments accordingly. -* libdiskfs/init-init.c: Likewise. -* libdiskfs/node-drop.c: Likewise. -* libdiskfs/node-make.c: Likewise. -* libdiskfs/node-nput.c: Likewise. -* libdiskfs/node-nputl.c: Likewise. -* libdiskfs/node-nref.c: Likewise. -* libdiskfs/node-nrefl.c: Likewise. -* libdiskfs/node-nrele.c: Likewise. -* libdiskfs/node-nrelel.c: Likewise. -* ext2fs/inode.c: Likewise. -* fatfs/inode.c: Likewise. -* isofs/inode.c: Likewise. -* tmpfs/node.c: Likewise. -* doc/hurd.texi: Likewise. ---- - doc/hurd.texi | 11 ++-------- - ext2fs/inode.c | 10 ++++----- - fatfs/inode.c | 22 ++++++++------------ - isofs/inode.c | 10 ++++----- - libdiskfs/diskfs.h | 15 ++++++-------- - libdiskfs/init-init.c | 2 -- - libdiskfs/node-drop.c | 9 +++------ - libdiskfs/node-make.c | 3 +-- - libdiskfs/node-nput.c | 54 +++++++++++++++++++------------------------------ - libdiskfs/node-nputl.c | 12 ++++------- - libdiskfs/node-nref.c | 10 ++++----- - libdiskfs/node-nrefl.c | 6 +++--- - libdiskfs/node-nrele.c | 48 +++++++++++++++++++++---------------------- - libdiskfs/node-nrelel.c | 9 +++------ - tmpfs/node.c | 10 ++++----- - 15 files changed, 93 insertions(+), 138 deletions(-) - -diff --git a/doc/hurd.texi b/doc/hurd.texi -index 07ddfb4..6cafdb9 100644 ---- a/doc/hurd.texi -+++ b/doc/hurd.texi -@@ -3780,10 +3780,6 @@ new thread and (eventually) get rid of the old one; the old thread won't - do any more syncs, regardless. - @end deftypefun - --@deftypevar spin_lock_t diskfs_node_refcnt_lock --Pager reference count lock. --@end deftypevar -- - @deftypevar int diskfs_readonly - Set to zero if the filesystem is currently writable. - @end deftypevar -@@ -3818,9 +3814,7 @@ Every file or directory is a diskfs @dfn{node}. The following functions - help your diskfs callbacks manage nodes and their references: - - @deftypefun void diskfs_drop_node (@w{struct node *@var{np}}) --Node @var{np} now has no more references; clean all state. The --@var{diskfs_node_refcnt_lock} must be held, and will be released upon --return. @var{np} must be locked. -+Node @var{np} now has no more references; clean all state. - @end deftypefun - - @deftypefun void diskfs_node_update (@w{struct node *@var{np}}, @w{int @var{wait}}) -@@ -4236,14 +4230,13 @@ without real users. - @deftypefun void diskfs_try_dropping_softrefs (@w{struct node *@var{np}}) - Node @var{np} has some light references, but has just lost its last hard - references. Take steps so that if any light references can be freed, --they are. Both @var{diskfs_node_refcnt_lock} and @var{np} are locked. -+they are. @var{np} is locked. - This function will be called after @code{diskfs_lost_hardrefs}. - @end deftypefun - - @deftypefun void diskfs_node_norefs (@w{struct node *@var{np}}) - Node @var{np} has no more references; free local state, including - @code{*@var{np}} if it shouldn't be retained. --@var{diskfs_node_refcnt_lock} is held. - @end deftypefun - - @deftypefun error_t diskfs_set_hypermetadata (@w{int @var{wait}}, @w{int @var{clean}}) -diff --git a/ext2fs/inode.c b/ext2fs/inode.c -index 0b3fa8b..d2bfe20 100644 ---- a/ext2fs/inode.c -+++ b/ext2fs/inode.c -@@ -188,12 +188,12 @@ diskfs_try_dropping_softrefs (struct node *np) - { - /* Check if someone reacquired a reference through the - nodehash. */ -- unsigned int references; -- pthread_spin_lock (&diskfs_node_refcnt_lock); -- references = np->references; -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -+ struct references result; -+ refcounts_references (&np->refcounts, &result); - -- if (references > 0) -+ /* An additional weak reference is acquired by libdiskfs across -+ calls to diskfs_try_dropping_softrefs. */ -+ if (result.hard > 0 || result.weak > 2) - { - /* A reference was reacquired through a hash table lookup. - It's fine, we didn't touch anything yet. */ -diff --git a/fatfs/inode.c b/fatfs/inode.c -index 1e5abdf..cdbe073 100644 ---- a/fatfs/inode.c -+++ b/fatfs/inode.c -@@ -235,14 +235,8 @@ diskfs_node_norefs (struct node *np) - if (np->dn->translator) - free (np->dn->translator); - -- /* It is safe to unlock diskfs_node_refcnt_lock here for a while because -- all references to the node have been deleted. */ - if (np->dn->dirnode) -- { -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -- diskfs_nrele (np->dn->dirnode); -- pthread_spin_lock (&diskfs_node_refcnt_lock); -- } -+ diskfs_nrele (np->dn->dirnode); - - assert (!np->dn->pager); - -@@ -260,12 +254,12 @@ diskfs_try_dropping_softrefs (struct node *np) - { - /* Check if someone reacquired a reference through the - nodehash. */ -- unsigned int references; -- pthread_spin_lock (&diskfs_node_refcnt_lock); -- references = np->references; -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -+ struct references result; -+ refcounts_references (&np->refcounts, &result); - -- if (references > 0) -+ /* An additional weak reference is acquired by libdiskfs across -+ calls to diskfs_try_dropping_softrefs. */ -+ if (result.hard > 0 || result.weak > 2) - { - /* A reference was reacquired through a hash table lookup. - It's fine, we didn't touch anything yet. */ -@@ -370,7 +364,7 @@ read_node (struct node *np, vm_address_t buf) - /* Files in fatfs depend on the directory that hold the file. */ - np->dn->dirnode = dp; - if (dp) -- dp->references++; -+ refcounts_ref (&dp->refcounts, NULL); - - pthread_rwlock_rdlock (&np->dn->dirent_lock); - -@@ -812,7 +806,7 @@ diskfs_alloc_node (struct node *dir, mode_t mode, struct node **node) - - /* FIXME: We know that readnode couldn't put this in. */ - np->dn->dirnode = dir; -- dir->references++; -+ refcounts_ref (&dir->refcounts, NULL); - - *node = np; - return 0; -diff --git a/isofs/inode.c b/isofs/inode.c -index ec874df..f175cb9 100644 ---- a/isofs/inode.c -+++ b/isofs/inode.c -@@ -533,12 +533,12 @@ diskfs_try_dropping_softrefs (struct node *np) - - /* Check if someone reacquired a reference through the - node_cache. */ -- unsigned int references; -- pthread_spin_lock (&diskfs_node_refcnt_lock); -- references = np->references; -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -+ struct references result; -+ refcounts_references (&np->refcounts, &result); - -- if (references > 0) -+ /* An additional weak reference is acquired by libdiskfs across -+ calls to diskfs_try_dropping_softrefs. */ -+ if (result.hard > 0 || result.weak > 2) - { - /* A reference was reacquired through a hash table lookup. - It's fine, we didn't touch anything yet. */ -diff --git a/libdiskfs/diskfs.h b/libdiskfs/diskfs.h -index 2c68aa3..38234a3 100644 ---- a/libdiskfs/diskfs.h -+++ b/libdiskfs/diskfs.h -@@ -96,8 +96,7 @@ struct node - - pthread_mutex_t lock; - -- int references; /* hard references */ -- int light_references; /* light references */ -+ refcounts_t refcounts; - - mach_port_t sockaddr; /* address for S_IFSOCK shortcut */ - -@@ -198,8 +197,6 @@ extern volatile struct mapped_time_value *diskfs_mtime; - be done by format independent code. */ - extern int diskfs_synchronous; - --extern pthread_spinlock_t diskfs_node_refcnt_lock; -- - extern int pager_port_type; - - /* Whether the filesystem is currently writable or not. */ -@@ -448,14 +445,15 @@ error_t diskfs_alloc_node (struct node *dp, mode_t mode, struct node **np); - void diskfs_free_node (struct node *np, mode_t mode); - - /* Node NP has no more references; free local state, including *NP -- if it isn't to be retained. diskfs_node_refcnt_lock is held. */ -+ if it isn't to be retained. */ - void diskfs_node_norefs (struct node *np); - - /* The user must define this function. Node NP has some light - references, but has just lost its last hard references. Take steps - so that if any light references can be freed, they are. NP is locked - as is the pager refcount lock. This function will be called after -- diskfs_lost_hardrefs. */ -+ diskfs_lost_hardrefs. An additional light reference is acquired by -+ libdiskfs across calls to this function. */ - void diskfs_try_dropping_softrefs (struct node *np); - - /* The user must define this funcction. Node NP has some light -@@ -611,9 +609,8 @@ void diskfs_spawn_first_thread (ports_demuxer_type demuxer); - diskfs_init_completed once it has a valid proc and auth port. */ - void diskfs_start_bootstrap (); - --/* Node NP now has no more references; clean all state. The -- _diskfs_node_refcnt_lock must be held, and will be released -- upon return. NP must be locked. */ -+/* Node NP now has no more references; clean all state. NP must be -+ locked. */ - void diskfs_drop_node (struct node *np); - - /* Set on disk fields from NP->dn_stat; update ctime, atime, and mtime -diff --git a/libdiskfs/init-init.c b/libdiskfs/init-init.c -index 7a7f248..6c94faa 100644 ---- a/libdiskfs/init-init.c -+++ b/libdiskfs/init-init.c -@@ -41,8 +41,6 @@ int _diskfs_noatime; - - struct hurd_port _diskfs_exec_portcell; - --pthread_spinlock_t diskfs_node_refcnt_lock = PTHREAD_SPINLOCK_INITIALIZER; -- - pthread_spinlock_t _diskfs_control_lock = PTHREAD_SPINLOCK_INITIALIZER; - int _diskfs_ncontrol_ports; - -diff --git a/libdiskfs/node-drop.c b/libdiskfs/node-drop.c -index 83eb590..fab3cfa 100644 ---- a/libdiskfs/node-drop.c -+++ b/libdiskfs/node-drop.c -@@ -31,9 +31,8 @@ free_modreqs (struct modreq *mr) - } - - --/* Node NP now has no more references; clean all state. The -- diskfs_node_refcnt_lock must be held, and will be released -- upon return. NP must be locked. */ -+/* Node NP now has no more references; clean all state. NP must be -+ locked. */ - void - diskfs_drop_node (struct node *np) - { -@@ -60,8 +59,7 @@ diskfs_drop_node (struct node *np) - and an nput. The next time through, this routine - will notice that the size is zero, and not have to - do anything. */ -- np->references++; -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -+ refcounts_ref (&np->refcounts, NULL); - diskfs_truncate (np, 0); - - /* Force allocsize to zero; if truncate consistently fails this -@@ -94,5 +92,4 @@ diskfs_drop_node (struct node *np) - assert (!np->sockaddr); - - diskfs_node_norefs (np); -- pthread_spin_unlock (&diskfs_node_refcnt_lock); - } -diff --git a/libdiskfs/node-make.c b/libdiskfs/node-make.c -index ff0cc0d..c7ca3b0 100644 ---- a/libdiskfs/node-make.c -+++ b/libdiskfs/node-make.c -@@ -29,8 +29,7 @@ init_node (struct node *np, struct disknode *dn) - np->dn_stat_dirty = 0; - - pthread_mutex_init (&np->lock, NULL); -- np->references = 1; -- np->light_references = 0; -+ refcounts_init (&np->refcounts, 1, 0); - np->owner = 0; - np->sockaddr = MACH_PORT_NULL; - -diff --git a/libdiskfs/node-nput.c b/libdiskfs/node-nput.c -index 5043ad1..2935ae2 100644 ---- a/libdiskfs/node-nput.c -+++ b/libdiskfs/node-nput.c -@@ -26,56 +26,44 @@ - void - diskfs_nput (struct node *np) - { -- int tried_drop_softrefs = 0; -+ struct references result; - -- loop: -- pthread_spin_lock (&diskfs_node_refcnt_lock); -- assert (np->references); -- np->references--; -- if (np->references + np->light_references == 0) -- diskfs_drop_node (np); -- else if (np->references == 0 && !tried_drop_softrefs) -- { -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -+ /* While we call the diskfs_try_dropping_softrefs, we need to hold -+ one reference. We use a weak reference for this purpose, which -+ we acquire by demoting our hard reference to a weak one. */ -+ refcounts_demote (&np->refcounts, &result); - -+ if (result.hard == 0) -+ { - /* This is our cue that something akin to "last process closes file" - in the POSIX.1 sense happened, so make sure any pending node time - updates now happen in a timely fashion. */ - diskfs_set_node_times (np); -- - diskfs_lost_hardrefs (np); - if (!np->dn_stat.st_nlink) - { -- /* There are no links. If there are soft references that -- can be dropped, we can't let them postpone deallocation. -- So attempt to drop them. But that's a user-supplied -- routine, which might result in further recursive calls to -- the ref-counting system. So we have to reacquire our -- reference around the call to forestall disaster. */ -- pthread_spin_lock (&diskfs_node_refcnt_lock); -- np->references++; -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -- - if (np->sockaddr != MACH_PORT_NULL) - { - mach_port_deallocate (mach_task_self (), np->sockaddr); - np->sockaddr = MACH_PORT_NULL; - } - -+ /* There are no links. If there are soft references that -+ can be dropped, we can't let them postpone deallocation. -+ So attempt to drop them. But that's a user-supplied -+ routine, which might result in further recursive calls to -+ the ref-counting system. This is not a problem, as we -+ hold a weak reference ourselves. */ - diskfs_try_dropping_softrefs (np); -- -- /* But there's no value in looping forever in this -- routine; only try to drop soft refs once. */ -- tried_drop_softrefs = 1; -- -- /* Now we can drop the reference back... */ -- goto loop; - } - pthread_mutex_unlock (&np->lock); - } -- else -- { -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -- pthread_mutex_unlock (&np->lock); -- } -+ -+ /* Finally get rid of our reference. */ -+ refcounts_deref_weak (&np->refcounts, &result); -+ -+ if (result.hard == 0 && result.weak == 0) -+ diskfs_drop_node (np); -+ -+ pthread_mutex_unlock (&np->lock); - } -diff --git a/libdiskfs/node-nputl.c b/libdiskfs/node-nputl.c -index 1959665..8dac16e 100644 ---- a/libdiskfs/node-nputl.c -+++ b/libdiskfs/node-nputl.c -@@ -25,14 +25,10 @@ - void - diskfs_nput_light (struct node *np) - { -- pthread_spin_lock (&diskfs_node_refcnt_lock); -- assert (np->light_references); -- np->light_references--; -- if (np->references + np->light_references == 0) -+ struct references result; -+ refcounts_deref_weak (&np->refcounts, &result); -+ if (result.hard == 0 && result.weak == 0) - diskfs_drop_node (np); - else -- { -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -- pthread_mutex_unlock (&np->lock); -- } -+ pthread_mutex_unlock (&np->lock); - } -diff --git a/libdiskfs/node-nref.c b/libdiskfs/node-nref.c -index 13cea05..89ffa4f 100644 ---- a/libdiskfs/node-nref.c -+++ b/libdiskfs/node-nref.c -@@ -26,12 +26,10 @@ - void - diskfs_nref (struct node *np) - { -- int new_hardref; -- pthread_spin_lock (&diskfs_node_refcnt_lock); -- np->references++; -- new_hardref = (np->references == 1); -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -- if (new_hardref) -+ struct references result; -+ refcounts_ref (&np->refcounts, &result); -+ assert (result.hard > 1 || result.weak > 0); -+ if (result.hard == 1) - { - pthread_mutex_lock (&np->lock); - diskfs_new_hardrefs (np); -diff --git a/libdiskfs/node-nrefl.c b/libdiskfs/node-nrefl.c -index 9692247..b7af409 100644 ---- a/libdiskfs/node-nrefl.c -+++ b/libdiskfs/node-nrefl.c -@@ -24,7 +24,7 @@ - void - diskfs_nref_light (struct node *np) - { -- pthread_spin_lock (&diskfs_node_refcnt_lock); -- np->light_references++; -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -+ struct references result; -+ refcounts_ref_weak (&np->refcounts, &result); -+ assert (result.hard > 0 || result.weak > 1); - } -diff --git a/libdiskfs/node-nrele.c b/libdiskfs/node-nrele.c -index cc68089..d962846 100644 ---- a/libdiskfs/node-nrele.c -+++ b/libdiskfs/node-nrele.c -@@ -28,38 +28,36 @@ - void - diskfs_nrele (struct node *np) - { -- int tried_drop_softrefs = 0; -+ struct references result; - -- loop: -- pthread_spin_lock (&diskfs_node_refcnt_lock); -- assert (np->references); -- np->references--; -- if (np->references + np->light_references == 0) -- { -- pthread_mutex_lock (&np->lock); -- diskfs_drop_node (np); -- } -- else if (np->references == 0) -+ /* While we call the diskfs_try_dropping_softrefs, we need to hold -+ one reference. We use a weak reference for this purpose, which -+ we acquire by demoting our hard reference to a weak one. */ -+ refcounts_demote (&np->refcounts, &result); -+ -+ if (result.hard == 0) - { - pthread_mutex_lock (&np->lock); -- pthread_spin_unlock (&diskfs_node_refcnt_lock); - diskfs_lost_hardrefs (np); -- if (!np->dn_stat.st_nlink && !tried_drop_softrefs) -+ if (!np->dn_stat.st_nlink) - { -- /* Same issue here as in nput; see that for explanation */ -- pthread_spin_lock (&diskfs_node_refcnt_lock); -- np->references++; -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -- -+ /* There are no links. If there are soft references that -+ can be dropped, we can't let them postpone deallocation. -+ So attempt to drop them. But that's a user-supplied -+ routine, which might result in further recursive calls to -+ the ref-counting system. This is not a problem, as we -+ hold a weak reference ourselves. */ - diskfs_try_dropping_softrefs (np); -- tried_drop_softrefs = 1; -- -- /* Now we can drop the reference back... */ -- pthread_mutex_unlock (&np->lock); -- goto loop; - } - pthread_mutex_unlock (&np->lock); - } -- else -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -+ -+ /* Finally get rid of our reference. */ -+ refcounts_deref_weak (&np->refcounts, &result); -+ -+ if (result.hard == 0 && result.weak == 0) -+ { -+ pthread_mutex_lock (&np->lock); -+ diskfs_drop_node (np); -+ } - } -diff --git a/libdiskfs/node-nrelel.c b/libdiskfs/node-nrelel.c -index ee53b22..dc4f920 100644 ---- a/libdiskfs/node-nrelel.c -+++ b/libdiskfs/node-nrelel.c -@@ -26,14 +26,11 @@ - void - diskfs_nrele_light (struct node *np) - { -- pthread_spin_lock (&diskfs_node_refcnt_lock); -- assert (np->light_references); -- np->light_references--; -- if (np->references + np->light_references == 0) -+ struct references result; -+ refcounts_deref_weak (&np->refcounts, &result); -+ if (result.hard == 0 && result.weak == 0) - { - pthread_mutex_lock (&np->lock); - diskfs_drop_node (np); - } -- else -- pthread_spin_unlock (&diskfs_node_refcnt_lock); - } -diff --git a/tmpfs/node.c b/tmpfs/node.c -index e126437..a230819 100644 ---- a/tmpfs/node.c -+++ b/tmpfs/node.c -@@ -284,12 +284,12 @@ diskfs_try_dropping_softrefs (struct node *np) - if (np->cache_id != 0) - { - /* Check if someone reacquired a reference. */ -- unsigned int references; -- pthread_spin_lock (&diskfs_node_refcnt_lock); -- references = np->references; -- pthread_spin_unlock (&diskfs_node_refcnt_lock); -+ struct references result; -+ refcounts_references (&np->refcounts, &result); - -- if (references > 0) -+ /* An additional weak reference is acquired by libdiskfs across -+ calls to diskfs_try_dropping_softrefs. */ -+ if (result.hard > 0 || result.weak > 2) - { - /* A reference was reacquired. It's fine, we didn't touch - anything yet. */ --- -2.0.0.rc2 - diff --git a/debian/patches/series b/debian/patches/series index 50d2de7b..2d703f80 100644 --- a/debian/patches/series +++ b/debian/patches/series @@ -41,11 +41,3 @@ xkb-compat.patch mach-defpager-protected-payload.patch -0001-tmpfs-use-a-thread-timeout.patch -0002-libports-use-a-global-hash-table-for-the-lookups.patch -0003-libports-lock-less-reference-counting-for-port_info-.patch -0004-ext2fs-use-a-seperate-lock-to-protect-nodehash.patch -0005-fatfs-use-a-seperate-lock-to-protect-nodehash.patch -0006-isofs-use-a-seperate-lock-to-protect-node_cache.patch -0007-tmpfs-use-a-seperate-lock-to-protect-all_nodes.patch -0008-libdiskfs-lock-less-reference-counting-of-nodes.patch |