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Diffstat (limited to 'erts/emulator/beam/erl_monitor_link.h')
| -rw-r--r-- | erts/emulator/beam/erl_monitor_link.h | 2354 |
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diff --git a/erts/emulator/beam/erl_monitor_link.h b/erts/emulator/beam/erl_monitor_link.h new file mode 100644 index 0000000000..ed7bf7d54a --- /dev/null +++ b/erts/emulator/beam/erl_monitor_link.h @@ -0,0 +1,2354 @@ +/* + * %CopyrightBegin% + * + * Copyright Ericsson AB 2018. All Rights Reserved. + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + * + * %CopyrightEnd% + */ + +/* + * Description: Monitor and link implementation. + * + * === Monitors ================================================== + * + * The monitor data structure contains: + * - an 'origin' part that should be inserted in a data structure + * of the origin entity, i.e., the entity monitoring another + * entity + * - a 'target' part that should be inserted in a data structure + * of the target entity, i.e., the entity being monitored by + * another entity + * - a shared part that contains information shared between both + * origin and target entities + * + * That is, the two halves of the monitor as well as shared data + * are allocated in one single continuous memory block. The + * origin and target parts can separately each be inserted in + * either a (red-black) tree, a (circular double linked) list, or + * in a process signal queue. + * + * Each process and port contains: + * - a monitor list for local target monitors that is accessed + * via the ERTS_P_LT_MONITORS() macro, and + * - a monitor tree for other monitors that is accessed via the + * ERTS_P_MONITORS() macro + * + * These fields of processes/ports are protected by the main lock + * of the process/port. These are only intended to be accessed by + * the process/port itself. When setting up or tearing down a + * monitor one should *only* operate on the monitor tree/list of + * the currently executing process/port and send signals to the + * other involved process/port so it can modify its own monitor + * tree/list by itself (see erl_proc_sig_queue.h). One should + * absolutely *not* acquire the lock of the other involved + * process/port and operate on its monitor tree/list directly. + * + * Each dist entry contains a monitor/link dist structure that + * contains: + * - a monitor tree for origin named monitors that is accessed via + * the field 'orig_name_monitors', and + * - a monitor list for other monitors that is accessed via the + * 'monitors' field. + * Monitors in these fields contain information about all monitors + * over this specific connection. + * + * The fields of the dist structure are protected by a mutex in + * the same dist structure. Operations on these fields are + * normally performed by the locally involved process only, + * except when a connection is taken down. However in the case + * of distributed named monitors that originates from another + * node this is not possible. That is this operation is also + * performed from another context that the locally involved + * process. + * + * Access to monitor trees are performed using the + * erts_monitor_tree_* functions below. Access to monitor lists + * are performed using the erts_monitor_list_* functions below. + * + * + * The different monitor types: + * + * --- ERTS_MON_TYPE_PROC ---------------------------------------- + * + * A local process (origin) monitors another local process + * (target). + * + * Origin: + * Other Item: Target process identifier + * Target: + * Other Item: Origin process identifier + * Shared: + * Key: Reference + * Name: Name (atom) if by name + * + * Valid keys are only ordinary internal references. + * + * Origin part of the monitor is stored in the monitor tree of + * origin process and target part of the monitor is stored in + * monitor list for local targets on the target process. + * + * --- ERTS_MON_TYPE_PORT ---------------------------------------- + * + * A local process (origin) monitors a local port (target), or a + * local port (origin) monitors a local process (target). + * + * Origin: + * Other Item: Target process/port identifier + * Target: + * Other Item: Origin process/port identifier + * Shared: + * Key: Reference + * Name: Name (atom) if by name + * + * Valid keys are only ordinary internal references. + * + * Origin part of the monitor is stored in the monitor tree of + * origin process/port and target part of the monitor is stored + * in monitor list for local targets on the target process/port. + * + * + * --- ERTS_MON_TYPE_TIME_OFFSET --------------------------------- + * + * A local process (origin) monitors time offset (target) + * + * Origin: + * Other Item: clock_service + * Target: + * Other Item: Origin process identifier + * Shared: + * Key: Reference + * + * Valid keys are only ordinary internal references. + * + * Origin part of the monitor is stored in the monitor tree of + * origin process and target part of the monitor is stored in + * monitor list referred by the variable 'time_offset_monitors' + * (see erl_time_sup.c). + * + * + * --- ERTS_MON_TYPE_DIST_PROC ----------------------------------- + * + * A local process (origin) monitors a remote process (target). + * Origin node on local process and target node on dist entry. + * + * Origin: + * Other Item: Remote process identifier/Node name + * if by name + * Target: + * Other Item: Local process identifier + * Shared: + * Key: Reference + * Name: Name (atom) if by name + * Dist: Pointer to dist structure + * + * Valid keys are only ordinary internal references. + * + * Origin part of the monitor is stored in the monitor tree of + * origin process and target part of the monitor is stored in + * monitor list referred by 'monitors' field of the dist + * structure. + * + * + * A remote process (origin) monitors a local process (target). + * Origin node on dist entry and target node on local process. + * + * Origin: + * Other Item: Local process identifier + * Target: + * Other Item: Remote process identifier + * Shared: + * Key: Reference + * Name: Name (atom) if by name + * + * Valid keys are only external references. + * + * If monitor by name, the origin part of the monitor is stored + * in the monitor tree referred by 'orig_name_monitors' field in + * dist structure; otherwise in the monitor list referred by + * 'monitors' field in dist structure. The target part of the + * monitor is stored in the monitor tree of the local target + * process. + * + * + * --- ERTS_MON_TYPE_RESOURCE ------------------------------------ + * + * A NIF resource (origin) monitors a process (target). + * + * Origin: + * Other Item: Target process identifier + * Target: + * Other Ptr: Pointer to resource + * Shared: + * Key: Reference + * + * Valid keys are only ordinary internal references. + * + * Origin part of the monitor is stored in the monitor tree of + * origin resource (see erl_nif.c) and target part of the + * monitor is stored in monitor list for local targets on the + * target process. + * + * --- ERTS_MON_TYPE_NODE ---------------------------------------- + * + * A local process (origin) monitors a distribution connection + * (target) via erlang:monitor_node(). + * + * Origin: + * Other Item: Node name (atom) + * Key: Node name + * Target: + * Other Item: Origin process identifier + * Key: Origin process identifier + * Shared: + * Refc: Number of invocations + * + * Valid keys are only node-name atoms and internal process + * identifiers. + * + * Origin part of the monitor is stored in the monitor tree of + * origin process and target part of the monitor is stored in + * monitor list referred by 'monitors' field of the dist + * structure. + * + * --- ERTS_MON_TYPE_NODES --------------------------------------- + * + * A local process (origin) monitors all connections (target), + * via net_kernel:monitor_nodes(). + * + * Origin: + * Other Item: Bit mask (small) + * Key: Bit mask + * Target: + * Other Item: Origin process identifier + * Key: Origin process identifier + * Shared: + * Refc: Number of invocations + * + * Valid keys are only small integers and internal process + * identifiers. + * + * Origin part of the monitor is stored in the monitor tree of + * origin process and target part of the monitor is stored in + * monitor list referred by the variable 'nodes_monitors' (see + * dist.c). + * + * --- ERTS_MON_TYPE_SUSPEND ------------------------------------- + * + * Suspend monitor. A local process (origin) suspends another + * local process (target). + * + * Origin: + * Other Item: Process identifier of suspendee + * (target) + * Key: Process identifier of suspendee + * (target) + * Target: + * Other Item: Process identifier of suspender + * (origin) + * Key: Process identifier of suspender + * (origin) + * Shared: + * Next: Pointer to another suspend monitor + * State: Number of suspends and a flag + * indicating if the suspend is + * active or not. + * + * Origin part of the monitor is stored in the monitor tree of + * origin process and target part of the monitor is stored in + * monitor list for local targets on the target process. + * + * + * + * === Links ===================================================== + * + * The link data structure contains: + * - an 'a' part that should be inserted in a data structure of + * one entity and contains the identifier of the other involved + * entity (b) + * - a 'b' part that should be inserted in a data structure of + * the other involved entity and contains the identifier of the + * other involved entity (a) + * - shared part that contains information shared between both + * involved entities + * + * That is, the two halves of the link as well as shared data + * are allocated in one single continuous memory block. The 'a' + * and the 'b' parts can separately each be inserted in either + * a (red-black) tree, a (circular double linked) list, or in a + * process signal queue. + * + * Each process and port contains: + * - a link tree for links that is accessed via the + * ERTS_P_LINKS() macro + * + * This field of processes/ports is protected by the main lock of + * the process/port. It is only intended to be accessed by the + * process/port itself. When setting up or tearing down a link + * one should *only* operate on the link tree of the currently + * executing process/port and send signals to the other involved + * process/port so it can modify its own monitor tree by itself + * (see erl_proc_sig_queue.h). One should absolutely *not* + * acquire the lock of the other involved process/port and + * operate on its link tree directly. + * + * Each dist entry contains a monitor/link dist structure that + * contains: + * - a link list for links via the 'links' field. + * Links in this field contain information about all links over + * this specific connection. + * + * The fields of the dist structure are protected by a mutex in + * the same dist structure. Operation on the 'links' fields are + * normally performed by the locally involved process only, + * except when a connection is taken down. + * + * Access to link trees are performed using the erts_link_tree_* + * functions below. Access to link lists are performed using the + * erts_link_list_* functions below. + * + * There can only be one link between the same pair of + * processes/ports. Since a link can be simultaneously initiated + * from both ends we always save the link data structure with the + * lowest address if multiple links should appear between the + * same pair of processes/ports. + * + * + * The different link types: + * + * --- ERTS_LNK_TYPE_PROC ----------------------------------------- + * + * A link between a local process A and a local process B. + * + * A: + * Other Item: B process identifier + * Key: B process identifier + * B: + * Other Item: A process identifier + * Key: A process identifier + * + * Valid keys are only internal process identifiers. + * + * 'A' part of the link stored in the link tree of process A and + * 'B' part of the link is stored in link tree of process B. + * + * --- ERTS_LNK_TYPE_PORT ----------------------------------------- + * + * A link between a local process/port A and a local process/port + * B. + * + * A: + * Other Item: B process/port identifier + * Key: B process/port identifier + * B: + * Other Item: A process/port identifier + * Key: A process/port identifier + * + * Valid keys are internal process identifiers and internal port + * identifiers. + * + * 'A' part of the link stored in the link tree of process/port + * A and 'B' part of the link is stored in link tree of + * process/port B. + * + * --- ERTS_LNK_TYPE_DIST_PROC ------------------------------------ + * + * A link between a local process and a remote process. Either of + * the processes can be used as A or B. + * + * A: + * Other Item: B process identifier + * Key: B process identifier + * B: + * Other Item: A process identifier + * Key: A process identifier + * Shared: + * Dist: Pointer to dist structure + * + * Valid keys are internal and external process identifiers. + * + * The part of the link with a remote pid as "other item" is + * stored in the link tree of the local process. The part of + * the link with a local pid as "other item" is stored in the + * links list of the dist structure. + * + * =============================================================== + * + * Author: Rickard Green + * + */ + +#ifndef ERL_MONITOR_LINK_H__ +#define ERL_MONITOR_LINK_H__ + +#define ERTS_PROC_SIG_QUEUE_TYPE_ONLY +#include "erl_proc_sig_queue.h" +#undef ERTS_PROC_SIG_QUEUE_TYPE_ONLY + +#if defined(DEBUG) || 0 +# define ERTS_ML_DEBUG +#else +# undef ERTS_ML_DEBUG +#endif + +#ifdef ERTS_ML_DEBUG +# define ERTS_ML_ASSERT ERTS_ASSERT +#else +# define ERTS_ML_ASSERT(E) ((void) 1) +#endif + +#define ERTS_MON_TYPE_MAX ((Uint16) 7) + +#define ERTS_MON_TYPE_PROC ((Uint16) 0) +#define ERTS_MON_TYPE_PORT ((Uint16) 1) +#define ERTS_MON_TYPE_TIME_OFFSET ((Uint16) 2) +#define ERTS_MON_TYPE_DIST_PROC ((Uint16) 3) +#define ERTS_MON_TYPE_RESOURCE ((Uint16) 4) +#define ERTS_MON_TYPE_NODE ((Uint16) 5) +#define ERTS_MON_TYPE_NODES ((Uint16) 6) +#define ERTS_MON_TYPE_SUSPEND ERTS_MON_TYPE_MAX + +#define ERTS_MON_LNK_TYPE_MAX (ERTS_MON_TYPE_MAX + ((Uint16) 3)) +#define ERTS_LNK_TYPE_MAX ERTS_MON_LNK_TYPE_MAX + +#define ERTS_LNK_TYPE_PROC (ERTS_MON_TYPE_MAX + ((Uint16) 1)) +#define ERTS_LNK_TYPE_PORT (ERTS_MON_TYPE_MAX + ((Uint16) 2)) +#define ERTS_LNK_TYPE_DIST_PROC ERTS_LNK_TYPE_MAX + +#define ERTS_ML_FLG_TARGET (((Uint16) 1) << 0) +#define ERTS_ML_FLG_IN_TABLE (((Uint16) 1) << 1) +#define ERTS_ML_FLG_IN_SUBTABLE (((Uint16) 1) << 2) +#define ERTS_ML_FLG_NAME (((Uint16) 1) << 3) +#define ERTS_ML_FLG_EXTENDED (((Uint16) 1) << 4) + +#define ERTS_ML_FLG_DBG_VISITED (((Uint16) 1) << 15) + +/* Flags that should be the same on both monitor/link halves */ +#define ERTS_ML_FLGS_SAME \ + (ERTS_ML_FLG_EXTENDED|ERTS_ML_FLG_NAME) + +typedef struct ErtsMonLnkNode__ ErtsMonLnkNode; + +typedef struct { + UWord parent; /* Parent ptr and flags... */ + ErtsMonLnkNode *right; + ErtsMonLnkNode *left; +} ErtsMonLnkTreeNode; + +typedef struct { + ErtsMonLnkNode *next; + ErtsMonLnkNode *prev; +} ErtsMonLnkListNode; + +struct ErtsMonLnkNode__ { + union { + ErtsSignalCommon signal; + ErtsMonLnkTreeNode tree; + ErtsMonLnkListNode list; + } node; + union { + Eterm item; + void *ptr; + } other; + Uint16 offset; /* offset from monitor/link data to this structure (node) */ + Uint16 key_offset; /* offset from this structure (node) to key */ + Uint16 flags; + Uint16 type; +}; + +typedef struct { + Eterm nodename; + Uint32 connection_id; + erts_atomic_t refc; + erts_mtx_t mtx; + int alive; + ErtsMonLnkNode *links; /* Link double linked circular list */ + ErtsMonLnkNode *monitors; /* Monitor double linked circular list */ + ErtsMonLnkNode *orig_name_monitors; /* Origin named monitors + read-black tree */ +} ErtsMonLnkDist; + +/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *\ + * Misc * +\* */ + +/** + * + * @brief Initialize monitor/link implementation + * + */ +void erts_monitor_link_init(void); + +/** + * + * @brief Create monitor/link dist structure to attach to dist entry + * + * Create dist structure containing monitor and link containers. This + * structure is to be attached to a connected dist entry. + * + * @param[in] nodename Node name as an atom + * + * @returns Pointer to dist structure + * + */ +ErtsMonLnkDist *erts_mon_link_dist_create(Eterm nodename); + +/** + * + * @brief Increase reference count of monitor/link dist structure + * + * @param[in] mld Pointer to dist structure + * + */ +ERTS_GLB_INLINE void erts_mon_link_dist_inc_refc(ErtsMonLnkDist *mld); + +/** + * + * @brief Decrease reference count of monitor/link dist structure + * + * @param[in] mld Pointer to dist structure + * + */ +ERTS_GLB_INLINE void erts_mon_link_dist_dec_refc(ErtsMonLnkDist *mld); + +/* internal functions... */ +ERTS_GLB_INLINE void erts_ml_dl_list_insert__(ErtsMonLnkNode **list, + ErtsMonLnkNode *ml); +ERTS_GLB_INLINE void erts_ml_dl_list_delete__(ErtsMonLnkNode **list, + ErtsMonLnkNode *ml); +ERTS_GLB_INLINE ErtsMonLnkNode *erts_ml_dl_list_first__(ErtsMonLnkNode *list); +ERTS_GLB_INLINE ErtsMonLnkNode *erts_ml_dl_list_last__(ErtsMonLnkNode *list); +void erts_mon_link_dist_destroy__(ErtsMonLnkDist *mld); +ERTS_GLB_INLINE void *erts_ml_node_to_main_struct__(ErtsMonLnkNode *mln); + +/* implementations for globally inlined misc functions... */ +#if ERTS_GLB_INLINE_INCL_FUNC_DEF + +ERTS_GLB_INLINE void +erts_mon_link_dist_inc_refc(ErtsMonLnkDist *mld) +{ + ERTS_ML_ASSERT(erts_atomic_read_nob(&mld->refc) > 0); + erts_atomic_inc_nob(&mld->refc); +} + +ERTS_GLB_INLINE void +erts_mon_link_dist_dec_refc(ErtsMonLnkDist *mld) +{ + ERTS_ML_ASSERT(erts_atomic_read_nob(&mld->refc) > 0); + if (erts_atomic_dec_read_nob(&mld->refc) == 0) + erts_mon_link_dist_destroy__(mld); +} + +ERTS_GLB_INLINE void * +erts_ml_node_to_main_struct__(ErtsMonLnkNode *mln) +{ + return (void *) (((char *) mln) - ((size_t) mln->offset)); +} + +ERTS_GLB_INLINE void +erts_ml_dl_list_insert__(ErtsMonLnkNode **list, ErtsMonLnkNode *ml) +{ + ErtsMonLnkNode *first = *list; + ERTS_ML_ASSERT(!(ml->flags & ERTS_ML_FLG_IN_TABLE)); + if (!first) { + ml->node.list.next = ml->node.list.prev = ml; + *list = ml; + } + else { + ERTS_ML_ASSERT(first->node.list.prev->node.list.next == first); + ERTS_ML_ASSERT(first->node.list.next->node.list.prev == first); + ml->node.list.next = first; + ml->node.list.prev = first->node.list.prev; + first->node.list.prev = ml; + ml->node.list.prev->node.list.next = ml; + } + ml->flags |= ERTS_ML_FLG_IN_TABLE; +} + +ERTS_GLB_INLINE void +erts_ml_dl_list_delete__(ErtsMonLnkNode **list, ErtsMonLnkNode *ml) +{ + ERTS_ML_ASSERT(ml->flags & ERTS_ML_FLG_IN_TABLE); + if (ml->node.list.next == ml) { + ERTS_ML_ASSERT(ml->node.list.prev == ml); + ERTS_ML_ASSERT(*list == ml); + + *list = NULL; + } + else { + ERTS_ML_ASSERT(ml->node.list.prev->node.list.next == ml); + ERTS_ML_ASSERT(ml->node.list.prev != ml); + ERTS_ML_ASSERT(ml->node.list.next->node.list.prev == ml); + ERTS_ML_ASSERT(ml->node.list.next != ml); + + if (*list == ml) + *list = ml->node.list.next; + ml->node.list.prev->node.list.next = ml->node.list.next; + ml->node.list.next->node.list.prev = ml->node.list.prev; + } + ml->flags &= ~ERTS_ML_FLG_IN_TABLE; +} + +ERTS_GLB_INLINE ErtsMonLnkNode * +erts_ml_dl_list_first__(ErtsMonLnkNode *list) +{ + return list; +} + +ERTS_GLB_INLINE ErtsMonLnkNode * +erts_ml_dl_list_last__(ErtsMonLnkNode *list) +{ + if (!list) + return NULL; + return list->node.list.prev; +} + +#endif /* ERTS_GLB_INLINE_INCL_FUNC_DEF */ + +/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *\ + * Monitor Operations * +\* */ + + +typedef struct ErtsMonLnkNode__ ErtsMonitor; + +typedef struct { + ErtsMonitor origin; + ErtsMonitor target; + Eterm ref; + erts_atomic32_t refc; +} ErtsMonitorData; + +typedef struct { + ErtsMonitorData md; + ErtsORefThing oref_thing; +} ErtsMonitorDataHeap; + +typedef struct ErtsMonitorDataExtended__ ErtsMonitorDataExtended; + +struct ErtsMonitorDataExtended__ { + ErtsMonitorData md; + union { + Eterm name; + Uint refc; + } u; + union { + struct erl_off_heap_header *ohhp; + ErtsMonitor *node_monitors; + } uptr; + ErtsMonLnkDist *dist; + Eterm heap[1]; /* heap start... */ +}; + +typedef struct ErtsMonitorSuspend__ ErtsMonitorSuspend; + +struct ErtsMonitorSuspend__ { + ErtsMonitorData md; /* origin = suspender; target = suspendee */ + ErtsMonitorSuspend *next; + erts_atomic_t state; +}; +#define ERTS_MSUSPEND_STATE_FLG_ACTIVE ((erts_aint_t) (((Uint) 1) << (sizeof(Uint)*8 - 1))) +#define ERTS_MSUSPEND_STATE_COUNTER_MASK (~ERTS_MSUSPEND_STATE_FLG_ACTIVE) + +/* + * --- Monitor tree operations --- + */ + +/** + * + * @brief Lookup a monitor in a monitor tree + * + * + * @param[in] root Pointer to root of monitor tree + * + * @param[in] key Key of monitor to lookup + * + * @returns Pointer to a monitor with the + * key 'key', or NULL if no such + * monitor was found + * + */ +ErtsMonitor *erts_monitor_tree_lookup(ErtsMonitor *root, Eterm key); + +/** + * + * @brief Lookup or insert a monitor in a monitor tree + * + * When the funcion is called it is assumed that: + * - 'mon' monitor is not part of any tree or list + * If the above is not true, bad things will happen. + * + * @param[in,out] root Pointer to pointer to root of monitor tree + * + * @param[in] mon Monitor to insert if no monitor + * with the same key already exists + * + * @returns Pointer to a monitor with the + * key 'key'. If no monitor with the key + * 'key' was found and 'mon' was inserted + * 'mon' is returned. + * + */ +ErtsMonitor *erts_monotor_tree_lookup_insert(ErtsMonitor **root, + ErtsMonitor *mon); + +/** + * + * @brief Lookup or create a node or a nodes monitor in a monitor tree. + * + * Looks up an origin monitor with the key 'target' in the monitor tree. + * If it is not found, creates a monitor and returns a pointer to the + * origin monitor. + * + * When the funcion is called it is assumed that: + * - no target monitors with the key 'target' exists in the tree. + * If the above is not true, bad things will happen. + * + * @param[in,out] root Pointer to pointer to root of monitor tree + * + * @param[out] created Pointer to integer. The integer is set to + * a non-zero value if no monitor with key + * 'target' was found, and a new monitor + * was created. If a monitor was found, it + * is set to zero. + * + * @param[in] type ERTS_MON_TYPE_NODE | ERTS_MON_TYPE_NODES + * + * @param[in] origin The key of the origin + * + * @param[in] target The key of the target + * + */ +ErtsMonitor *erts_monitor_tree_lookup_create(ErtsMonitor **root, int *created, + Uint16 type, Eterm origin, + Eterm target); + +/** + * + * @brief Insert a monitor in a monitor tree + * + * When the funcion is called it is assumed that: + * - no monitors with the same key that 'mon' exist in the tree + * - 'mon' is not part of any list of tree + * If the above are not true, bad things will happen. + * + * @param[in,out] root Pointer to pointer to root of monitor tree + * + * @param[in] mon Monitor to insert. + * + */ +void erts_monitor_tree_insert(ErtsMonitor **root, ErtsMonitor *mon); + +/** + * + * @brief Replace a monitor in a monitor tree + * + * When the funcion is called it is assumed that: + * - 'old' monitor and 'new' monitor have exactly the same key + * - 'old' monitor is part of the tree + * - 'new' monitor is not part of any tree or list + * If the above are not true, bad things will happen. + * + * @param[in,out] root Pointer to pointer to root of monitor tree + * + * @param[in] old Monitor to remove from the tree + * + * @param[in] new Monitor to insert into the tree + * + */ +void erts_monitor_tree_replace(ErtsMonitor **root, ErtsMonitor *old, + ErtsMonitor *new); + +/** + * + * @brief Delete a monitor from a monitor tree + * + * When the funcion is called it is assumed that: + * - 'mon' monitor is part of the tree + * If the above is not true, bad things will happen. + * + * @param[in,out] root Pointer to pointer to root of monitor tree + * + * @param[in] mon Monitor to remove from the tree + * + */ +void erts_monitor_tree_delete(ErtsMonitor **root, ErtsMonitor *mon); + +/** + * + * @brief Call a function for each monitor in a monitor tree + * + * The funcion 'func' will be called with a pointer to a monitor + * as first argument and 'arg' as second argument for each monitor + * in the tree referred to by 'root'. + * + * @param[in] root Pointer to root of monitor tree + * + * @param[in] func Pointer to function to call + * + * @param[in] arg Argument to pass as second argument in + * calls to 'func' + * + */ +void erts_monitor_tree_foreach(ErtsMonitor *root, + void (*func)(ErtsMonitor *, void *), + void *arg); + +/** + * + * @brief Call a function for each monitor in a monitor tree. Yield + * if lots of monitors exist. + * + * The funcion 'func' will be called with a pointer to a monitor + * as first argument and 'arg' as second argument for each monitor + * in the tree referred to by 'root'. + * + * It is assumed that: + * - *yspp equals NULL on first call + * - this function is repetedly called with *yspp set + * as set when previous call returned until a non-zero + * value is returned. + * - no modifications are made on the tree between first call + * and the call that returns a non-zero value + * If the above are not true, bad things will happen. + * + * @param[in] root Pointer to root of monitor tree + * + * @param[in] func Pointer to function to call + * + * @param[in] arg Argument to pass as second argument in + * calls to 'func' + * + * @param[in,out] vyspp Pointer to a pointer to an internal state + * used by this function. At initial call + * *yspp should be NULL. When done *yspp + * will be NULL. + * + * @param[in] limit Maximum amount of monitors to process + * before yielding. + * + * @returns A non-zero value when all monitors has been + * processed, and zero when more work is needed. + * + */ +int erts_monitor_tree_foreach_yielding(ErtsMonitor *root, + void (*func)(ErtsMonitor *, void *), + void *arg, + void **vyspp, + Sint limit); + +/** + * + * @brief Delete all monitors from a monitor tree and call a function for + * each monitor + * + * The funcion 'func' will be called with a pointer to a monitor + * as first argument and 'arg' as second argument for each monitor + * in the tree referred to by 'root'. + * + * @param[in,out] root Pointer to pointer to root of monitor tree + * + * @param[in] func Pointer to function to call + * + * @param[in] arg Argument to pass as second argument in + * calls to 'func' + * + */ +void erts_monitor_tree_foreach_delete(ErtsMonitor **root, + void (*func)(ErtsMonitor *, void *), + void *arg); + +/** + * + * @brief Delete all monitors from a monitor tree and call a function for + * each monitor + * + * The funcion 'func' will be called with a pointer to a monitor + * as first argument and 'arg' as second argument for each monitor + * in the tree referred to by 'root'. + * + * It is assumed that: + * - *yspp equals NULL on first call + * - this function is repetededly called with *yspp set + * as set when previous call returned until a non-zero + * value is returned. + * - no modifications are made on the tree between first call + * and the call that returns a non-zero value + * If the above are not true, bad things will happen. + * + * @param[in,out] root Pointer to pointer to root of monitor tree + * + * @param[in] func Pointer to function to call + * + * @param[in] arg Argument to pass as second argument in + * calls to 'func' + * + * @param[in,out] vyspp Pointer to a pointer to an internal state + * used by this function. At initial call + * *yspp should be NULL. When done *yspp + * will be NULL. + * + * @param[in] limit Maximum amount of monitors to process + * before yielding. + * + * @returns A non-zero value when all monitors has been + * processed, and zero when more work is needed. + * + */ +int erts_monitor_tree_foreach_delete_yielding(ErtsMonitor **root, + void (*func)(ErtsMonitor *, void *), + void *arg, + void **vyspp, + Sint limit); + +/* + * --- Monitor list operations -- + */ + +/** + * + * @brief Insert a monitor in a monitor list + * + * When the funcion is called it is assumed that: + * - 'mon' monitor is not part of any list or tree + * If the above is not true, bad things will happen. + * + * @param[in,out] list Pointer to pointer to monitor list + * + * @param[in] mon Monitor to insert + * + */ +ERTS_GLB_INLINE void erts_monitor_list_insert(ErtsMonitor **list, ErtsMonitor *mon); + +/** + * + * @brief Delete a monitor from a monitor list + * + * When the funcion is called it is assumed that: + * - 'mon' monitor is part of the list + * If the above is not true, bad things will happen. + * + * @param[in,out] list Pointer to pointer to monitor list + * + * @param[in] mon Monitor to remove from the list + * + */ +ERTS_GLB_INLINE void erts_monitor_list_delete(ErtsMonitor **list, ErtsMonitor *mon); + +/** + * + * @brief Get a pointer to first monitor in a monitor list + * + * The monitor will still remain in the list after the return + * + * @param[in] list Pointer to monitor list + * + * @returns Pointer to first monitor in list if + * list is not empty. If list is empty + * NULL is returned. + * + */ +ERTS_GLB_INLINE ErtsMonitor *erts_monitor_list_first(ErtsMonitor *list); + +/** + * + * @brief Get a pointer to last monitor in a monitor list + * + * The monitor will still remain in the list after the return + * + * @param[in] list Pointer to monitor list + * + * @returns Pointer to last monitor in list if + * list is not empty. If list is empty + * NULL is returned. + * + */ +ERTS_GLB_INLINE ErtsMonitor *erts_monitor_list_last(ErtsMonitor *list); + +/** + * + * @brief Call a function for each monitor in a monitor list + * + * The funcion 'func' will be called with a pointer to a monitor + * as first argument and 'arg' as second argument for each monitor + * in the tree referred to by 'list'. + * + * @param[in] list Pointer to root of monitor list + * + * @param[in] func Pointer to function to call + * + * @param[in] arg Argument to pass as second argument in + * calls to 'func' + * + */ +void erts_monitor_list_foreach(ErtsMonitor *list, + void (*func)(ErtsMonitor *, void *), + void *arg); + +/** + * + * @brief Call a function for each monitor in a monitor list. Yield + * if lots of monitors exist. + * + * The funcion 'func' will be called with a pointer to a monitor + * as first argument and 'arg' as second argument for each monitor + * in the tree referred to by 'root'. + * + * It is assumed that: + * - *yspp equals NULL on first call + * - this function is repetedly called with *yspp set + * as set when previous call returned until a non-zero + * value is returned. + * - no modifications are made on the tree between first call + * and the call that returns a non-zero value + * If the above are not true, bad things will happen. + * + * @param[in] list Pointer to monitor list + * + * @param[in] func Pointer to function to call + * + * @param[in] arg Argument to pass as second argument in + * calls to 'func' + * + * @param[in,out] vyspp Pointer to a pointer to an internal state + * used by this function. At initial call + * *yspp should be NULL. When done *yspp + * will be NULL. + * + * @param[in] limit Maximum amount of monitors to process + * before yielding. + * + * @returns A non-zero value when all monitors has been + * processed, and zero when more work is needed. + * + */ +int erts_monitor_list_foreach_yielding(ErtsMonitor *list, + void (*func)(ErtsMonitor *, void *), + void *arg, + void **vyspp, + Sint limit); + +/** + * + * @brief Delete all monitors from a monitor list and call a function for + * each monitor + * + * The funcion 'func' will be called with a pointer to a monitor + * as first argument and 'arg' as second argument for each monitor + * in the tree referred to by 'root'. + * + * @param[in,out] list Pointer to pointer to monitor list + * + * @param[in] func Pointer to function to call + * + * @param[in] arg Argument to pass as second argument in + * calls to 'func' + * + */ +void erts_monitor_list_foreach_delete(ErtsMonitor **list, + void (*func)(ErtsMonitor *, void *), + void *arg); + +/** + * + * @brief Delete all monitors from a monitor list and call a function for + * each monitor + * + * The funcion 'func' will be called with a pointer to a monitor + * as first argument and 'arg' as second argument for each monitor + * in the tree referred to by 'root'. + * + * It is assumed that: + * - *yspp equals NULL on first call + * - this function is repetededly called with *yspp set + * as set when previous call returned until a non-zero + * value is returned. + * - no modifications are made on the tree between first + * and the call that returns a non-zero value + * If the above are not true, bad things will happen. + * + * @param[in,out] list Pointer to pointer to monitor list + * + * @param[in] func Pointer to function to call + * + * @param[in] arg Argument to pass as second argument in + * calls to 'func' + * + * @param[in,out] vyspp Pointer to a pointer to an internal state + * used by this function. At initial call + * *yspp should be NULL. When done *yspp + * will be NULL. + * + * @param[in] limit Maximum amount of monitors to process + * before yielding. + * + * @returns A non-zero value when all monitors has been + * processed, and zero when more work is needed. + * + */ +int erts_monitor_list_foreach_delete_yielding(ErtsMonitor **list, + void (*func)(ErtsMonitor *, void *), + void *arg, + void **vyspp, + Sint limit); + +/* + * --- Misc monitor operations --- + */ + +/** + * + * @brief Create a monitor + * + * Can create all types of monitors + * + * When the funcion is called it is assumed that: + * - 'ref' is an internal ordinary reference if type is ERTS_MON_TYPE_PROC, + * ERTS_MON_TYPE_PORT, ERTS_MON_TYPE_TIME_OFFSET, or ERTS_MON_TYPE_RESOURCE + * - 'ref' is NIL if type is ERTS_MON_TYPE_NODE, ERTS_MON_TYPE_NODES, or + * ERTS_MON_TYPE_SUSPEND + * - 'ref' is and ordinary internal reference or an external reference if + * type is ERTS_MON_TYPE_DIST_PROC + * - 'name' is an atom or NIL if type is ERTS_MON_TYPE_PROC, + * ERTS_MON_TYPE_PORT, or ERTS_MON_TYPE_DIST_PROC + * - 'name is NIL if type is ERTS_MON_TYPE_TIME_OFFSET, ERTS_MON_TYPE_RESOURCE, + * ERTS_MON_TYPE_NODE, ERTS_MON_TYPE_NODES, or ERTS_MON_TYPE_SUSPEND + * If the above is not true, bad things will happen. + * + * @param[in] type ERTS_MON_TYPE_PROC, ERTS_MON_TYPE_PORT, + * ERTS_MON_TYPE_TIME_OFFSET, ERTS_MON_TYPE_DIST_PROC, + * ERTS_MON_TYPE_RESOURCE, ERTS_MON_TYPE_NODE, + * ERTS_MON_TYPE_NODES, or ERTS_MON_TYPE_SUSPEND + * + * @param[in] ref A reference or NIL depending on type + * + * @param[in] origin The key of the origin + * + * @param[in] target The key of the target + * + * @param[in] name An atom (the name) or NIL depending on type + * + * @returns A pointer to monitor data structure + * + */ +ErtsMonitorData *erts_monitor_create(Uint16 type, Eterm ref, Eterm origin, + Eterm target, Eterm name); + +/** + * + * @brief Get pointer to monitor data structure + * + * @param[in] mon Pointer to monitor + * + * @returns Pointer to monitor data structure + * + */ +ERTS_GLB_INLINE ErtsMonitorData *erts_monitor_to_data(ErtsMonitor *mon); + +/** + * + * @brief Check if monitor is a target monitor + * + * @param[in] mon Pointer to monitor to check + * + * @returns A non-zero value if target monitor; + * otherwise zero + * + */ +ERTS_GLB_INLINE int erts_monitor_is_target(ErtsMonitor *mon); + +/** + * + * @brief Check if monitor is an origin monitor + * + * @param[in] mon Pointer to monitor to check + * + * @returns A non-zero value if origin monitor; + * otherwise zero + * + */ +ERTS_GLB_INLINE int erts_monitor_is_origin(ErtsMonitor *mon); + +/** + * + * @brief Check if monitor is in tree or list + * + * @param[in] mon Pointer to monitor to check + * + * @returns A non-zero value if in tree or list; + * otherwise zero + * + */ +ERTS_GLB_INLINE int erts_monitor_is_in_table(ErtsMonitor *mon); + +/** + * + * @brief Release monitor + * + * When both the origin and the target part of the monitor have + * been released the monitor structure will be deallocated. + * + * When the funcion is called it is assumed that: + * - 'mon' monitor is not part of any list or tree + * - 'mon' is not referred to by any other structures + * If the above are not true, bad things will happen. + * + * @param[in] mon Pointer to monitor + * + */ +ERTS_GLB_INLINE void erts_monitor_release(ErtsMonitor *mon); + +/** + * + * @brief Release both target and origin monitor structures simultaneously + * + * Release both the origin and target parts of the monitor + * simultaneously and deallocate the structure. + * + * When the funcion is called it is assumed that: + * - Neither the origin part nor the target part of the monitor + * are not part of any list or tree + * - Neither the origin part nor the target part of the monitor + * are referred to by any other structures + * If the above are not true, bad things will happen. + * + * @param[in] mdp Pointer to monitor data structure + * + */ +ERTS_GLB_INLINE void erts_monitor_release_both(ErtsMonitorData *mdp); + +/** + * + * @brief Insert monitor in dist monitor tree or list + * + * When the funcion is called it is assumed that: + * - 'mon' monitor is not part of any list or tree + * If the above is not true, bad things will happen. + * + * @param[in] mon Pointer to monitor + * + * @param[in] dist Pointer to dist structure + * + * @returns A non-zero value if inserted; + * otherwise, zero. The monitor + * is not inserted if the dist + * structure has been set in a + * dead state. + * + */ +ERTS_GLB_INLINE int erts_monitor_dist_insert(ErtsMonitor *mon, ErtsMonLnkDist *dist); + +/** + * + * @brief Delete monitor from dist monitor tree or list + * + * When the funcion is called it is assumed that: + * - 'mon' monitor earler has been inserted into 'dist' + * If the above is not true, bad things will happen. + * + * @param[in] mon Pointer to monitor + * + * @param[in] dist Pointer to dist structure + * + * @returns A non-zero value if deleted; + * otherwise, zero. The monitor + * is not deleted if the dist + * structure has been set in a + * dead state or if it has already + * been deleted. + * + */ +ERTS_GLB_INLINE int erts_monitor_dist_delete(ErtsMonitor *mon); + +/** + * + * @brief Set dead dist structure on monitor + * + * @param[in] mon Pointer to monitor + * + * @param[in] nodename Name of remote node + * + */ +void +erts_monitor_set_dead_dist(ErtsMonitor *mon, Eterm nodename); + +/** + * + * @brief Get charged size of monitor + * + * If the other side of the monitor has been released, the + * whole size of the monitor data structure is returned; otherwise, + * half of the size is returned. + * + * When the funcion is called it is assumed that: + * - 'mon' has not been released + * If the above is not true, bad things will happen. + * + * @param[in] mon Pointer to monitor + * + * @returns Charged size in bytes + * + */ +Uint erts_monitor_size(ErtsMonitor *mon); + + +/* internal function... */ +void erts_monitor_destroy__(ErtsMonitorData *mdp); + +/* implementations for globally inlined monitor functions... */ +#if ERTS_GLB_INLINE_INCL_FUNC_DEF + +ERTS_GLB_INLINE int +erts_monitor_is_target(ErtsMonitor *mon) +{ + return !!(mon->flags & ERTS_ML_FLG_TARGET); +} + +ERTS_GLB_INLINE int +erts_monitor_is_origin(ErtsMonitor *mon) +{ + return !(mon->flags & ERTS_ML_FLG_TARGET); +} + +ERTS_GLB_INLINE int +erts_monitor_is_in_table(ErtsMonitor *mon) +{ + return !!(mon->flags & ERTS_ML_FLG_IN_TABLE); +} + +ERTS_GLB_INLINE void +erts_monitor_list_insert(ErtsMonitor **list, ErtsMonitor *mon) +{ + erts_ml_dl_list_insert__((ErtsMonLnkNode **) list, (ErtsMonLnkNode *) mon); +} + +ERTS_GLB_INLINE void +erts_monitor_list_delete(ErtsMonitor **list, ErtsMonitor *mon) +{ + erts_ml_dl_list_delete__((ErtsMonLnkNode **) list, (ErtsMonLnkNode *) mon); +} + +ERTS_GLB_INLINE ErtsMonitor * +erts_monitor_list_first(ErtsMonitor *list) +{ + return (ErtsMonitor *) erts_ml_dl_list_first__((ErtsMonLnkNode *) list); +} + +ERTS_GLB_INLINE ErtsMonitor * +erts_monitor_list_last(ErtsMonitor *list) +{ + return (ErtsMonitor *) erts_ml_dl_list_last__((ErtsMonLnkNode *) list); +} + +#ifdef ERTS_ML_DEBUG +extern size_t erts_monitor_origin_offset; +extern size_t erts_monitor_origin_key_offset; +extern size_t erts_monitor_target_offset; +extern size_t erts_monitor_target_key_offset; +extern size_t erts_monitor_node_key_offset; +#endif + +ERTS_GLB_INLINE ErtsMonitorData * +erts_monitor_to_data(ErtsMonitor *mon) +{ + ErtsMonitorData *mdp = erts_ml_node_to_main_struct__((ErtsMonLnkNode *) mon); + +#ifdef ERTS_ML_DEBUG + ERTS_ML_ASSERT(!(mdp->origin.flags & ERTS_ML_FLG_TARGET)); + ERTS_ML_ASSERT(erts_monitor_origin_offset == (size_t) mdp->origin.offset); + ERTS_ML_ASSERT(!!(mdp->target.flags & ERTS_ML_FLG_TARGET)); + ERTS_ML_ASSERT(erts_monitor_target_offset == (size_t) mdp->target.offset); + if (mon->type == ERTS_MON_TYPE_NODE || mon->type == ERTS_MON_TYPE_NODES + || mon->type == ERTS_MON_TYPE_SUSPEND) { + ERTS_ML_ASSERT(erts_monitor_node_key_offset == (size_t) mdp->origin.key_offset); + ERTS_ML_ASSERT(erts_monitor_node_key_offset == (size_t) mdp->target.key_offset); + } + else { + ERTS_ML_ASSERT(erts_monitor_origin_key_offset == (size_t) mdp->origin.key_offset); + ERTS_ML_ASSERT(erts_monitor_target_key_offset == (size_t) mdp->target.key_offset); + } +#endif + + return mdp; +} + +ERTS_GLB_INLINE void +erts_monitor_release(ErtsMonitor *mon) +{ + ErtsMonitorData *mdp = erts_monitor_to_data(mon); + ERTS_ML_ASSERT(erts_atomic32_read_nob(&mdp->refc) > 0); + + if (erts_atomic32_dec_read_nob(&mdp->refc) == 0) { + ERTS_ML_ASSERT(!(mdp->origin.flags & ERTS_ML_FLG_IN_TABLE)); + ERTS_ML_ASSERT(!(mdp->target.flags & ERTS_ML_FLG_IN_TABLE)); + + erts_monitor_destroy__(mdp); + } +} + +ERTS_GLB_INLINE void +erts_monitor_release_both(ErtsMonitorData *mdp) +{ + ERTS_ML_ASSERT((mdp->origin.flags & ERTS_ML_FLGS_SAME) + == (mdp->target.flags & ERTS_ML_FLGS_SAME)); + ERTS_ML_ASSERT(erts_atomic32_read_nob(&mdp->refc) >= 2); + + if (erts_atomic32_add_read_nob(&mdp->refc, (erts_aint32_t) -2) == 0) { + ERTS_ML_ASSERT(!(mdp->origin.flags & ERTS_ML_FLG_IN_TABLE)); + ERTS_ML_ASSERT(!(mdp->target.flags & ERTS_ML_FLG_IN_TABLE)); + + erts_monitor_destroy__(mdp); + } +} + +ERTS_GLB_INLINE int +erts_monitor_dist_insert(ErtsMonitor *mon, ErtsMonLnkDist *dist) +{ + ErtsMonitorDataExtended *mdep; + int insert; + + ERTS_ML_ASSERT(mon->flags & ERTS_ML_FLG_EXTENDED); + ERTS_ML_ASSERT(mon->type == ERTS_MON_TYPE_DIST_PROC + || mon->type == ERTS_MON_TYPE_NODE); + + mdep = (ErtsMonitorDataExtended *) erts_monitor_to_data(mon); + + ERTS_ML_ASSERT(!mdep->dist); + ERTS_ML_ASSERT(dist); + mdep->dist = dist; + + erts_mon_link_dist_inc_refc(dist); + + erts_mtx_lock(&dist->mtx); + + insert = dist->alive; + if (insert) { + if ((mon->flags & (ERTS_ML_FLG_NAME + | ERTS_ML_FLG_TARGET)) == ERTS_ML_FLG_NAME) + erts_monitor_tree_insert(&dist->orig_name_monitors, mon); + else + erts_monitor_list_insert(&dist->monitors, mon); + } + + erts_mtx_unlock(&dist->mtx); + + return insert; +} + +ERTS_GLB_INLINE int +erts_monitor_dist_delete(ErtsMonitor *mon) +{ + ErtsMonitorDataExtended *mdep; + ErtsMonLnkDist *dist; + Uint16 flags; + int delete; + + ERTS_ML_ASSERT(mon->flags & ERTS_ML_FLG_EXTENDED); + ERTS_ML_ASSERT(mon->type == ERTS_MON_TYPE_DIST_PROC + || mon->type == ERTS_MON_TYPE_NODE); + + mdep = (ErtsMonitorDataExtended *) erts_monitor_to_data(mon); + dist = mdep->dist; + ERTS_ML_ASSERT(dist); + + erts_mtx_lock(&dist->mtx); + + flags = mon->flags; + delete = !!dist->alive & !!(flags & ERTS_ML_FLG_IN_TABLE); + if (delete) { + if ((flags & (ERTS_ML_FLG_NAME + | ERTS_ML_FLG_TARGET)) == ERTS_ML_FLG_NAME) + erts_monitor_tree_delete(&dist->orig_name_monitors, mon); + else + erts_monitor_list_delete(&dist->monitors, mon); + } + + erts_mtx_unlock(&dist->mtx); + + return delete; +} + + +#endif /* ERTS_GLB_INLINE_INCL_FUNC_DEF */ + +/* suspend monitors... */ +ErtsMonitorSuspend *erts_monitor_suspend_create(Eterm pid); +ErtsMonitorSuspend *erts_monitor_suspend_tree_lookup_create(ErtsMonitor **root, + int *created, + Eterm pid); +void erts_monitor_suspend_destroy(ErtsMonitorSuspend *msp); + +ERTS_GLB_INLINE ErtsMonitorSuspend *erts_monitor_suspend(ErtsMonitor *mon); + +#if ERTS_GLB_INLINE_INCL_FUNC_DEF + +ERTS_GLB_INLINE ErtsMonitorSuspend *erts_monitor_suspend(ErtsMonitor *mon) +{ + ERTS_ML_ASSERT(!mon || mon->type == ERTS_MON_TYPE_SUSPEND); + return (ErtsMonitorSuspend *) mon; +} + +#endif + +/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *\ + * Link Operations * +\* */ + +typedef struct ErtsMonLnkNode__ ErtsLink; + +typedef struct { + ErtsLink a; + ErtsLink b; + erts_atomic32_t refc; +} ErtsLinkData; + +typedef struct { + ErtsLinkData ld; + struct erl_off_heap_header *ohhp; + ErtsMonLnkDist *dist; + Eterm heap[1]; /* heap start... */ +} ErtsLinkDataExtended; + +/* + * --- Link tree operations --- + */ + +/** + * + * @brief Lookup a link in a link tree + * + * + * @param[in] root Pointer to root of link tree + * + * @param[in] key Key of link to lookup + * + * @returns Pointer to a link with the + * key 'key', or NULL if no such + * link was found + * + */ +ErtsLink *erts_link_tree_lookup(ErtsLink *root, Eterm item); + +/** + * + * @brief Lookup or insert a link in a link tree + * + * When the funcion is called it is assumed that: + * - 'lnk' link is not part of any tree or list + * If the above is not true, bad things will happen. + * + * @param[in,out] root Pointer to pointer to root of link tree + * + * @param[in] lnk Link to insert if no link + * with the same key already exists + * + * @returns Pointer to a link with the + * key 'key'. If no link with the key + * 'key' was found and 'lnk' was inserted + * 'lnk' is returned. + * + */ +ErtsLink *erts_link_tree_lookup_insert(ErtsLink **root, ErtsLink *lnk); + +/** + * + * @brief Lookup or create a link in a link tree. + * + * Looks up a link with the key 'other' in the link tree. If it is not + * found, creates and insert a link with the key 'other'. + * + * @param[in,out] root Pointer to pointer to root of link tree + * + * @param[out] created Pointer to integer. The integer is set to + * a non-zero value if no link with key + * 'other' was found, and a new link + * was created. If a link was found, it + * is set to zero. + * + * @param[in] type Type of link + * + * @param[in] this Id of this entity + * + * @param[in] other Id of other entity + * + */ +ErtsLink *erts_link_tree_lookup_create(ErtsLink **root, int *created, + Uint16 type, Eterm this, Eterm other); + +/** + * + * @brief Insert a link in a link tree + * + * When the funcion is called it is assumed that: + * - no links with the same key that 'lnk' exist in the tree + * - 'lnk' is not part of any list of tree + * If the above are not true, bad things will happen. + * + * @param[in,out] root Pointer to pointer to root of link tree + * + * @param[in] lnk Link to insert. + * + */ +void erts_link_tree_insert(ErtsLink **root, ErtsLink *lnk); + +/** + * + * @brief Replace a link in a link tree + * + * When the funcion is called it is assumed that: + * - 'old' link and 'new' link have exactly the same key + * - 'old' link is part of the tree + * - 'new' link is not part of any tree or list + * If the above are not true, bad things will happen. + * + * @param[in,out] root Pointer to pointer to root of link tree + * + * @param[in] old Link to remove from the tree + * + * @param[in] new Link to insert into the tree + * + */ +void erts_link_tree_replace(ErtsLink **root, ErtsLink *old, ErtsLink *new); + +/** + * + * @brief Replace a link in a link tree if key already exist based on adress + * + * Inserts the link 'lnk' in the tree if no link with the same key + * already exists in tree. If a link with the same key exists in + * the tree and 'lnk' has a lower address than the link in the + * tree, the existing link in the tree is replaced by 'lnk'. + * + * When the funcion is called it is assumed that: + * - 'lnk' link is not part of any tree or list + * If the above are not true, bad things will happen. + * + * @param[in,out] root Pointer to pointer to root of link tree + * + * @param[in] lnk Link to insert into the tree + * + * @returns A pointer to the link that is not part + * of the tree after this operation. + * + */ +ERTS_GLB_INLINE ErtsLink *erts_link_tree_insert_addr_replace(ErtsLink **root, + ErtsLink *lnk); + +/** + * + * @brief Delete a link from a link tree + * + * When the funcion is called it is assumed that: + * - 'lnk' link is part of the tree + * If the above is not true, bad things will happen. + * + * @param[in,out] root Pointer to pointer to root of link tree + * + * @param[in] lnk Link to remove from the tree + * + */ +void erts_link_tree_delete(ErtsLink **root, ErtsLink *lnk); + +/** + * + * @brief Delete a link from a link tree based on key + * + * If link 'lnk' is in the tree, 'lnk' is deleted from the tree. + * If link 'lnk' is not in the tree, another link with the same + * key as 'lnk' is deleted from the tree if such a link exist. + * + * When the funcion is called it is assumed that: + * - if 'lnk' link is part of a tree or list, it is part of this tree + * If the above is not true, bad things will happen. + * + * @param[in,out] root Pointer to pointer to root of link tree + * + * @param[in] lnk Link to remove from the tree + * + * @returns A pointer to the link that was deleted + * from the tree, or NULL in case no link + * was deleted from the tree + * + */ +ERTS_GLB_INLINE ErtsLink *erts_link_tree_key_delete(ErtsLink **root, ErtsLink *lnk); + +/** + * + * @brief Call a function for each link in a link tree + * + * The funcion 'func' will be called with a pointer to a link + * as first argument and 'arg' as second argument for each link + * in the tree referred to by 'root'. + * + * @param[in] root Pointer to root of link tree + * + * @param[in] func Pointer to function to call + * + * @param[in] arg Argument to pass as second argument in + * calls to 'func' + * + */ +void erts_link_tree_foreach(ErtsLink *root, + void (*func)(ErtsLink *, void *), + void *arg); + +/** + * + * @brief Call a function for each link in a link tree. Yield if lots + * of links exist. + * + * The funcion 'func' will be called with a pointer to a link + * as first argument and 'arg' as second argument for each link + * in the tree referred to by 'root'. + * + * It is assumed that: + * - *yspp equals NULL on first call + * - this function is repetedly called with *yspp set + * as set when previous call returned until a non-zero + * value is returned. + * - no modifications are made on the tree between first call + * and the call that returns a non-zero value + * If the above are not true, bad things will happen. + * + * @param[in] root Pointer to root of link tree + * + * @param[in] func Pointer to function to call + * + * @param[in] arg Argument to pass as second argument in + * calls to 'func' + * + * @param[in,out] vyspp Pointer to a pointer to an internal state + * used by this function. At initial call + * *yspp should be NULL. When done *yspp + * will be NULL. + * + * @param[in] limit Maximum amount of links to process + * before yielding. + * + * @returns A non-zero value when all links has been + * processed, and zero when more work is needed. + * + */ +int erts_link_tree_foreach_yielding(ErtsLink *root, + void (*func)(ErtsLink *, void *), + void *arg, + void **vyspp, + Sint limit); + +/** + * + * @brief Delete all links from a link tree and call a function for + * each link + * + * The funcion 'func' will be called with a pointer to a link + * as first argument and 'arg' as second argument for each link + * in the tree referred to by 'root'. + * + * @param[in,out] root Pointer to pointer to root of link tree + * + * @param[in] func Pointer to function to call + * + * @param[in] arg Argument to pass as second argument in + * calls to 'func' + * + */ +void erts_link_tree_foreach_delete(ErtsLink **root, + void (*func)(ErtsLink *, void *), + void *arg); + +/** + * + * @brief Delete all links from a link tree and call a function for + * each link + * + * The funcion 'func' will be called with a pointer to a link + * as first argument and 'arg' as second argument for each link + * in the tree referred to by 'root'. + * + * It is assumed that: + * - *yspp equals NULL on first call + * - this function is repetededly called with *yspp set + * as set when previous call returned until a non-zero + * value is returned. + * - no modifications are made on the tree between first call + * and the call that returns a non-zero value + * If the above are not true, bad things will happen. + * + * @param[in,out] root Pointer to pointer to root of link tree + * + * @param[in] func Pointer to function to call + * + * @param[in] arg Argument to pass as second argument in + * calls to 'func' + * + * @param[in,out] vyspp Pointer to a pointer to an internal state + * used by this function. At initial call + * *yspp should be NULL. When done *yspp + * will be NULL. + * + * @param[in] limit Maximum amount of links to process + * before yielding. + * + * @returns A non-zero value when all links has been + * processed, and zero when more work is needed. + * + */ +int erts_link_tree_foreach_delete_yielding(ErtsLink **root, + void (*func)(ErtsLink *, void *), + void *arg, + void **vyspp, + Sint limit); + +/* + * --- Link list operations --- + */ + +/** + * + * @brief Insert a link in a link list + * + * When the funcion is called it is assumed that: + * - 'lnk' link is not part of any list or tree + * If the above is not true, bad things will happen. + * + * @param[in,out] list Pointer to pointer to link list + * + * @param[in] lnk Link to insert + * + */ +ERTS_GLB_INLINE void erts_link_list_insert(ErtsLink **list, ErtsLink *lnk); + +/** + * + * @brief Delete a link from a link list + * + * When the funcion is called it is assumed that: + * - 'lnk' link is part of the list + * If the above is not true, bad things will happen. + * + * @param[in,out] list Pointer to pointer to link list + * + * @param[in] lnk Link to remove from the list + * + */ +ERTS_GLB_INLINE void erts_link_list_delete(ErtsLink **list, ErtsLink *lnk); + +/** + * + * @brief Get a pointer to first link in a link list + * + * The link will still remain in the list after the return + * + * @param[in] list Pointer to link list + * + * @returns Pointer to first link in list if + * list is not empty. If list is empty + * NULL is returned. + * + */ +ERTS_GLB_INLINE ErtsLink *erts_link_list_first(ErtsLink *list); + +/** + * + * @brief Get a pointer to last link in a link list + * + * The link will still remain in the list after the return + * + * @param[in] list Pointer to link list + * + * @returns Pointer to last link in list if + * list is not empty. If list is empty + * NULL is returned. + * + */ +ERTS_GLB_INLINE ErtsLink *erts_link_list_last(ErtsLink *list); + +/** + * + * @brief Call a function for each link in a link list + * + * The funcion 'func' will be called with a pointer to a link + * as first argument and 'arg' as second argument for each link + * in the tree referred to by 'list'. + * + * @param[in] list Pointer to root of link list + * + * @param[in] func Pointer to function to call + * + * @param[in] arg Argument to pass as second argument in + * calls to 'func' + * + */ +void erts_link_list_foreach(ErtsLink *list, + void (*func)(ErtsLink *, void *), + void *arg); + +/** + * + * @brief Call a function for each link in a link list. Yield + * if lots of links exist. + * + * The funcion 'func' will be called with a pointer to a link + * as first argument and 'arg' as second argument for each link + * in the tree referred to by 'root'. + * + * It is assumed that: + * - *yspp equals NULL on first call + * - this function is repetedly called with *yspp set + * as set when previous call returned until a non-zero + * value is returned. + * - no modifications are made on the tree between first call + * and the call that returns a non-zero value + * If the above are not true, bad things will happen. + * + * @param[in] list Pointer to link list + * + * @param[in] func Pointer to function to call + * + * @param[in] arg Argument to pass as second argument in + * calls to 'func' + * + * @param[in,out] vyspp Pointer to a pointer to an internal state + * used by this function. At initial call + * *yspp should be NULL. When done *yspp + * will be NULL. + * + * @param[in] limit Maximum amount of links to process + * before yielding. + * + * @returns A non-zero value when all links has been + * processed, and zero when more work is needed. + * + */ +int erts_link_list_foreach_yielding(ErtsLink *list, + void (*func)(ErtsLink *, void *), + void *arg, + void **vyspp, + Sint limit); + +/** + * + * @brief Delete all links from a link list and call a function for + * each link + * + * The funcion 'func' will be called with a pointer to a link + * as first argument and 'arg' as second argument for each link + * in the tree referred to by 'root'. + * + * @param[in,out] list Pointer to pointer to link list + * + * @param[in] func Pointer to function to call + * + * @param[in] arg Argument to pass as second argument in + * calls to 'func' + * + */ +void erts_link_list_foreach_delete(ErtsLink **list, + void (*func)(ErtsLink *, void *), + void *arg); + +/** + * + * @brief Delete all links from a link list and call a function for + * each link + * + * The funcion 'func' will be called with a pointer to a link + * as first argument and 'arg' as second argument for each link + * in the tree referred to by 'root'. + * + * It is assumed that: + * - *yspp equals NULL on first call + * - this function is repetededly called with *yspp set + * as set when previous call returned until a non-zero + * value is returned. + * - no modifications are made on the tree between first + * and the call that returns a non-zero value + * If the above are not true, bad things will happen. + * + * @param[in,out] list Pointer to pointer to link list + * + * @param[in] func Pointer to function to call + * + * @param[in] arg Argument to pass as second argument in + * calls to 'func' + * + * @param[in,out] vyspp Pointer to a pointer to an internal state + * used by this function. At initial call + * *yspp should be NULL. When done *yspp + * will be NULL. + * + * @param[in] limit Maximum amount of links to process + * before yielding. + * + * @returns A non-zero value when all links has been + * processed, and zero when more work is needed. + * + */ +int erts_link_list_foreach_delete_yielding(ErtsLink **list, + void (*func)(ErtsLink *, void *), + void *arg, + void **vyspp, + Sint limit); + +/* + * --- Misc link operations --- + */ + +/** + * + * @brief Create a link + * + * Can create all types of links + * + * When the funcion is called it is assumed that: + * - 'ref' is an internal ordinary reference if type is ERTS_MON_TYPE_PROC, + * ERTS_MON_TYPE_PORT, ERTS_MON_TYPE_TIME_OFFSET, or ERTS_MON_TYPE_RESOURCE + * - 'ref' is NIL if type is ERTS_MON_TYPE_NODE or ERTS_MON_TYPE_NODES + * - 'ref' is and ordinary internal reference or an external reference if + * type is ERTS_MON_TYPE_DIST_PROC + * - 'name' is an atom or NIL if type is ERTS_MON_TYPE_PROC, + * ERTS_MON_TYPE_PORT, or ERTS_MON_TYPE_DIST_PROC + * - 'name is NIL if type is ERTS_MON_TYPE_TIME_OFFSET, ERTS_MON_TYPE_RESOURCE, + * ERTS_MON_TYPE_NODE, or ERTS_MON_TYPE_NODES + * If the above is not true, bad things will happen. + * + * @param[in] type ERTS_MON_TYPE_PROC, ERTS_MON_TYPE_PORT, + * ERTS_MON_TYPE_TIME_OFFSET, ERTS_MON_TYPE_DIST_PROC, + * ERTS_MON_TYPE_RESOURCE, ERTS_MON_TYPE_NODE, + * or ERTS_MON_TYPE_NODES + * + * @param[in] a The key of entity a. Link structure a will + * have field other.item set to 'b'. + * + * @param[in] b The key of entity b. Link structure b will + * have field other.item set to 'a'. + * + */ +ErtsLinkData *erts_link_create(Uint16 type, Eterm a, Eterm b); + +/** + * + * @brief Get pointer to link data structure + * + * @param[in] lnk Pointer to link + * + * @returns Pointer to link data structure + * + */ +ERTS_GLB_INLINE ErtsLinkData *erts_link_to_data(ErtsLink *lnk); + +/** + * + * @brief Get pointer to the other link structure part of the link + * + * @param[in] lnk Pointer to link + * + * @param[out] ldpp Pointer to pointer to link data structure, + * if a non-NULL value is passed in the call + * + * @returns Pointer to other link + * + */ +ERTS_GLB_INLINE ErtsLink *erts_link_to_other(ErtsLink *lnk, ErtsLinkData **ldpp); + +/** + * + * @brief Check if link is in tree or list + * + * @param[in] lnk Pointer to lnk to check + * + * @returns A non-zero value if in tree or list; + * otherwise zero + * + */ +ERTS_GLB_INLINE int erts_link_is_in_table(ErtsLink *lnk); + +/** + * + * @brief Release link + * + * When both link halves part of the link have been released the link + * structure will be deallocated. + * + * When the funcion is called it is assumed that: + * - 'lnk' link is not part of any list or tree + * - 'lnk' is not referred to by any other structures + * If the above are not true, bad things will happen. + * + * @param[in] lnk Pointer to link + * + */ +ERTS_GLB_INLINE void erts_link_release(ErtsLink *lnk); + +/** + * + * @brief Release both link halves of a link simultaneously + * + * Release both halves of a link simultaneously and deallocate + * the structure. + * + * When the funcion is called it is assumed that: + * - Neither of the parts of the link are part of any list or tree + * - Neither of the parts of the link or the link data structure + * are referred to by any other structures + * If the above are not true, bad things will happen. + * + * @param[in] mdp Pointer to link data structure + * + */ +ERTS_GLB_INLINE void erts_link_release_both(ErtsLinkData *ldp); + +/** + * + * @brief Insert link in dist link list + * + * When the funcion is called it is assumed that: + * - 'lnk' link is not part of any list or tree + * If the above is not true, bad things will happen. + * + * @param[in] lnk Pointer to link + * + * @param[in] dist Pointer to dist structure + * + * @returns A non-zero value if inserted; + * otherwise, zero. The link + * is not inserted if the dist + * structure has been set in a + * dead state. + * + */ +ERTS_GLB_INLINE int erts_link_dist_insert(ErtsLink *lnk, ErtsMonLnkDist *dist); + +/** + * + * @brief Delete link from dist link list + * + * When the funcion is called it is assumed that: + * - 'lnk' link earler has been inserted into 'dist' + * If the above is not true, bad things will happen. + * + * @param[in] lnk Pointer to link + * + * @param[in] dist Pointer to dist structure + * + * @returns A non-zero value if deleted; + * otherwise, zero. The link + * is not deleted if the dist + * structure has been set in a + * dead state or if it has already + * been deleted. + * + */ +ERTS_GLB_INLINE int erts_link_dist_delete(ErtsLink *lnk); + +/** + * + * @brief Set dead dist structure on link + * + * @param[in] lnk Pointer to link + * + * @param[in] nodename Name of remote node + * + */ +void +erts_link_set_dead_dist(ErtsLink *lnk, Eterm nodename); + +/** + * + * @brief Get charged size of link + * + * If the other side of the link has been released, the + * whole size of the link data structure is returned; otherwise, + * half of the size is returned. + * + * When the funcion is called it is assumed that: + * - 'lnk' has not been released + * If the above is not true, bad things will happen. + * + * @param[in] lnk Pointer to link + * + * @returns Charged size in bytes + * + */ +Uint erts_link_size(ErtsLink *lnk); + +/* internal function... */ +void erts_link_destroy__(ErtsLinkData *ldp); + +/* implementations for globally inlined link functions... */ +#if ERTS_GLB_INLINE_INCL_FUNC_DEF + +#ifdef ERTS_ML_DEBUG +extern size_t erts_link_a_offset; +extern size_t erts_link_b_offset; +extern size_t erts_link_key_offset; +#endif + +ERTS_GLB_INLINE ErtsLinkData * +erts_link_to_data(ErtsLink *lnk) +{ + ErtsLinkData *ldp = erts_ml_node_to_main_struct__((ErtsMonLnkNode *) lnk); + +#ifdef ERTS_ML_DEBUG + ERTS_ML_ASSERT(erts_link_a_offset == (size_t) ldp->a.offset); + ERTS_ML_ASSERT(erts_link_key_offset == (size_t) ldp->a.key_offset); + ERTS_ML_ASSERT(erts_link_b_offset == (size_t) ldp->b.offset); + ERTS_ML_ASSERT(erts_link_key_offset == (size_t) ldp->b.key_offset); +#endif + + return ldp; +} + +ERTS_GLB_INLINE ErtsLink * +erts_link_to_other(ErtsLink *lnk, ErtsLinkData **ldpp) +{ + ErtsLinkData *ldp = erts_link_to_data(lnk); + if (ldpp) + *ldpp = ldp; + return lnk == &ldp->a ? &ldp->b : &ldp->a; +} + +ERTS_GLB_INLINE int +erts_link_is_in_table(ErtsLink *lnk) +{ + return !!(lnk->flags & ERTS_ML_FLG_IN_TABLE); +} + +ERTS_GLB_INLINE void +erts_link_list_insert(ErtsLink **list, ErtsLink *lnk) +{ + erts_ml_dl_list_insert__((ErtsMonLnkNode **) list, (ErtsMonLnkNode *) lnk); +} + +ERTS_GLB_INLINE void +erts_link_list_delete(ErtsLink **list, ErtsLink *lnk) +{ + erts_ml_dl_list_delete__((ErtsMonLnkNode **) list, (ErtsMonLnkNode *) lnk); +} + +ERTS_GLB_INLINE ErtsLink * +erts_link_list_first(ErtsLink *list) +{ + return (ErtsLink *) erts_ml_dl_list_first__((ErtsMonLnkNode *) list); +} + +ERTS_GLB_INLINE ErtsLink * +erts_link_list_last(ErtsLink *list) +{ + return (ErtsLink *) erts_ml_dl_list_last__((ErtsMonLnkNode *) list); +} + +ERTS_GLB_INLINE void +erts_link_release(ErtsLink *lnk) +{ + ErtsLinkData *ldp = erts_link_to_data(lnk); + ERTS_ML_ASSERT(!(lnk->flags & ERTS_ML_FLG_IN_TABLE)); + ERTS_ML_ASSERT(erts_atomic32_read_nob(&ldp->refc) > 0); + if (erts_atomic32_dec_read_nob(&ldp->refc) == 0) + erts_link_destroy__(ldp); +} + +ERTS_GLB_INLINE void +erts_link_release_both(ErtsLinkData *ldp) +{ + ERTS_ML_ASSERT(!(ldp->a.flags & ERTS_ML_FLG_IN_TABLE)); + ERTS_ML_ASSERT(!(ldp->b.flags & ERTS_ML_FLG_IN_TABLE)); + ERTS_ML_ASSERT(erts_atomic32_read_nob(&ldp->refc) >= 2); + if (erts_atomic32_add_read_nob(&ldp->refc, (erts_aint32_t) -2) == 0) + erts_link_destroy__(ldp); +} + +ERTS_GLB_INLINE ErtsLink * +erts_link_tree_insert_addr_replace(ErtsLink **root, ErtsLink *lnk) +{ + ErtsLink *lnk2 = erts_link_tree_lookup_insert(root, lnk); + if (!lnk2) + return NULL; + if (lnk2 < lnk) + return lnk; + erts_link_tree_replace(root, lnk2, lnk); + return lnk2; +} + +ERTS_GLB_INLINE ErtsLink * +erts_link_tree_key_delete(ErtsLink **root, ErtsLink *lnk) +{ + ErtsLink *dlnk; + if (erts_link_is_in_table(lnk)) + dlnk = lnk; + else + dlnk = erts_link_tree_lookup(*root, lnk->other.item); + if (dlnk) + erts_link_tree_delete(root, dlnk); + return dlnk; +} + +ERTS_GLB_INLINE int +erts_link_dist_insert(ErtsLink *lnk, ErtsMonLnkDist *dist) +{ + ErtsLinkDataExtended *ldep; + int insert; + + ERTS_ML_ASSERT(lnk->flags & ERTS_ML_FLG_EXTENDED); + ERTS_ML_ASSERT(lnk->type == ERTS_LNK_TYPE_DIST_PROC); + + ldep = (ErtsLinkDataExtended *) erts_link_to_data(lnk); + + ERTS_ML_ASSERT(!ldep->dist); + ERTS_ML_ASSERT(dist); + ldep->dist = dist; + + erts_mon_link_dist_inc_refc(dist); + + erts_mtx_lock(&dist->mtx); + + insert = dist->alive; + if (insert) + erts_link_list_insert(&dist->links, lnk); + + erts_mtx_unlock(&dist->mtx); + + return insert; +} + +ERTS_GLB_INLINE int +erts_link_dist_delete(ErtsLink *lnk) +{ + ErtsLinkDataExtended *ldep; + ErtsMonLnkDist *dist; + int delete; + + ERTS_ML_ASSERT(lnk->flags & ERTS_ML_FLG_EXTENDED); + ERTS_ML_ASSERT(lnk->type == ERTS_LNK_TYPE_DIST_PROC); + + ldep = (ErtsLinkDataExtended *) erts_link_to_data(lnk); + dist = ldep->dist; + if (!dist) + return -1; + + erts_mtx_lock(&dist->mtx); + + delete = !!dist->alive & !!(lnk->flags & ERTS_ML_FLG_IN_TABLE); + if (delete) + erts_link_list_delete(&dist->links, lnk); + + erts_mtx_unlock(&dist->mtx); + + return delete; +} + + +#endif /* ERTS_GLB_INLINE_INCL_FUNC_DEF */ + +#endif /* ERL_MONITOR_LINK_H__ */ |