| 1,5 → 1,6 |
|---|
| /* |
| * Copyright (c) 2009 Martin Decky |
| * Copyright (c) 2009 Jiri Svoboda |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| 41,20 → 42,13 |
|---|
| #include "ns.h" |
| |
| #define TASK_HASH_TABLE_CHAINS 256 |
| #define P2I_HASH_TABLE_CHAINS 256 |
| |
| static int get_id_by_phone(ipcarg_t phone_hash, task_id_t *id); |
| |
| /* TODO: |
| * |
| * The current implementation of waiting on a task is not perfect. If somebody |
| * wants to wait on a task which has already finished before the NS asked |
| * the kernel to receive notifications, it would block indefinitively. |
| * |
| * A solution to this is to fail immediately on a task for which no creation |
| * notification was received yet. However, there is a danger of a race condition |
| * in this solution -- the caller has to make sure that it is not trying to wait |
| * before the NS has a change to receive the task creation notification. This |
| * can be assured by waiting for this event in task_spawn(). |
| * |
| * Finally, as there is currently no convention that each task has to be waited |
| * As there is currently no convention that each task has to be waited |
| * for, the NS can leak memory because of the zombie tasks. |
| * |
| */ |
| 62,8 → 56,10 |
|---|
| /** Task hash table item. */ |
| typedef struct { |
| link_t link; |
| task_id_t id; /**< Task ID. */ |
| bool destroyed; |
| task_id_t id; /**< Task ID. */ |
| bool finished; /**< Task is done. */ |
| bool have_rval; /**< Task returned a value. */ |
| int retval; /**< The return value. */ |
| } hashed_task_t; |
| |
| /** Compute hash index into task hash table. |
| 83,7 → 79,7 |
|---|
| /** Compare a key with hashed item. |
| * |
| * @param key Array of keys. |
| * @param keys Must be lesser or equal to 2. |
| * @param keys Must be less than or equal to 2. |
| * @param item Pointer to a hash table item. |
| * |
| * @return Non-zero if the key matches the item, zero otherwise. |
| 125,6 → 121,65 |
|---|
| /** Task hash table structure. */ |
| static hash_table_t task_hash_table; |
| |
| typedef struct { |
| link_t link; |
| ipcarg_t phash; /**< Task ID. */ |
| task_id_t id; /**< Task ID. */ |
| } p2i_entry_t; |
| |
| /** Compute hash index into task hash table. |
| * |
| * @param key Array of keys. |
| * @return Hash index corresponding to key[0]. |
| * |
| */ |
| static hash_index_t p2i_hash(unsigned long *key) |
| { |
| assert(key); |
| return (*key % TASK_HASH_TABLE_CHAINS); |
| } |
| |
| /** Compare a key with hashed item. |
| * |
| * @param key Array of keys. |
| * @param keys Must be less than or equal to 1. |
| * @param item Pointer to a hash table item. |
| * |
| * @return Non-zero if the key matches the item, zero otherwise. |
| * |
| */ |
| static int p2i_compare(unsigned long key[], hash_count_t keys, link_t *item) |
| { |
| assert(key); |
| assert(keys == 1); |
| assert(item); |
| |
| p2i_entry_t *e = hash_table_get_instance(item, p2i_entry_t, link); |
| |
| return (key[0] == e->phash); |
| } |
| |
| /** Perform actions after removal of item from the hash table. |
| * |
| * @param item Item that was removed from the hash table. |
| * |
| */ |
| static void p2i_remove(link_t *item) |
| { |
| assert(item); |
| free(hash_table_get_instance(item, p2i_entry_t, link)); |
| } |
| |
| /** Operations for task hash table. */ |
| static hash_table_operations_t p2i_ops = { |
| .hash = p2i_hash, |
| .compare = p2i_compare, |
| .remove_callback = p2i_remove |
| }; |
| |
| /** Map phone hash to task ID */ |
| static hash_table_t phone_to_id; |
| |
| /** Pending task wait structure. */ |
| typedef struct { |
| link_t link; |
| 141,10 → 196,13 |
|---|
| printf(NAME ": No memory available for tasks\n"); |
| return ENOMEM; |
| } |
| |
| if (!hash_table_create(&phone_to_id, P2I_HASH_TABLE_CHAINS, |
| 1, &p2i_ops)) { |
| printf(NAME ": No memory available for tasks\n"); |
| return ENOMEM; |
| } |
| |
| if (event_subscribe(EVENT_WAIT, 0) != EOK) |
| printf(NAME ": Error registering wait notifications\n"); |
| |
| list_initialize(&pending_wait); |
| |
| return EOK; |
| 154,6 → 212,7 |
|---|
| void process_pending_wait(void) |
| { |
| link_t *cur; |
| task_exit_t texit; |
| |
| loop: |
| for (cur = pending_wait.next; cur != &pending_wait; cur = cur->next) { |
| 169,12 → 228,16 |
|---|
| continue; |
| |
| hashed_task_t *ht = hash_table_get_instance(link, hashed_task_t, link); |
| if (!ht->destroyed) |
| if (!ht->finished) |
| continue; |
| |
| if (!(pr->callid & IPC_CALLID_NOTIFICATION)) |
| ipc_answer_0(pr->callid, EOK); |
| |
| if (!(pr->callid & IPC_CALLID_NOTIFICATION)) { |
| texit = ht->have_rval ? TASK_EXIT_NORMAL : |
| TASK_EXIT_UNEXPECTED; |
| ipc_answer_2(pr->callid, EOK, texit, |
| ht->retval); |
| } |
| |
| hash_table_remove(&task_hash_table, keys, 2); |
| list_remove(cur); |
| free(pr); |
| 182,66 → 245,27 |
|---|
| } |
| } |
| |
| static void fail_pending_wait(task_id_t id, int rc) |
| void wait_for_task(task_id_t id, ipc_call_t *call, ipc_callid_t callid) |
| { |
| link_t *cur; |
| |
| loop: |
| for (cur = pending_wait.next; cur != &pending_wait; cur = cur->next) { |
| pending_wait_t *pr = list_get_instance(cur, pending_wait_t, link); |
| |
| if (pr->id == id) { |
| if (!(pr->callid & IPC_CALLID_NOTIFICATION)) |
| ipc_answer_0(pr->callid, rc); |
| |
| list_remove(cur); |
| free(pr); |
| goto loop; |
| } |
| } |
| } |
| ipcarg_t retval; |
| task_exit_t texit; |
| |
| void wait_notification(wait_type_t et, task_id_t id) |
| { |
| unsigned long keys[2] = { |
| LOWER32(id), |
| UPPER32(id) |
| }; |
| |
| link_t *link = hash_table_find(&task_hash_table, keys); |
| |
| if (link == NULL) { |
| hashed_task_t *ht = |
| (hashed_task_t *) malloc(sizeof(hashed_task_t)); |
| if (ht == NULL) { |
| fail_pending_wait(id, ENOMEM); |
| return; |
| } |
| |
| link_initialize(&ht->link); |
| ht->id = id; |
| ht->destroyed = (et == TASK_CREATE) ? false : true; |
| hash_table_insert(&task_hash_table, keys, &ht->link); |
| } else { |
| hashed_task_t *ht = |
| hash_table_get_instance(link, hashed_task_t, link); |
| ht->destroyed = (et == TASK_CREATE) ? false : true; |
| } |
| } |
| |
| void wait_for_task(task_id_t id, ipc_call_t *call, ipc_callid_t callid) |
| { |
| ipcarg_t retval; |
| unsigned long keys[2] = { |
| LOWER32(id), |
| UPPER32(id) |
| }; |
| |
| link_t *link = hash_table_find(&task_hash_table, keys); |
| hashed_task_t *ht = (link != NULL) ? |
| hash_table_get_instance(link, hashed_task_t, link) : NULL; |
| |
| if ((ht == NULL) || (!ht->destroyed)) { |
| |
| if (ht == NULL) { |
| /* No such task exists. */ |
| retval = ENOENT; |
| goto out; |
| } |
| |
| if (!ht->finished) { |
| /* Add to pending list */ |
| pending_wait_t *pr = |
| (pending_wait_t *) malloc(sizeof(pending_wait_t)); |
| 260,10 → 284,131 |
|---|
| retval = EOK; |
| |
| out: |
| if (!(callid & IPC_CALLID_NOTIFICATION)) |
| ipc_answer_0(callid, retval); |
| if (!(callid & IPC_CALLID_NOTIFICATION)) { |
| texit = ht->have_rval ? TASK_EXIT_NORMAL : TASK_EXIT_UNEXPECTED; |
| ipc_answer_2(callid, retval, texit, ht->retval); |
| } |
| } |
| |
| int ns_task_id_intro(ipc_call_t *call) |
| { |
| task_id_t id; |
| unsigned long keys[2]; |
| link_t *link; |
| p2i_entry_t *e; |
| hashed_task_t *ht; |
| |
| id = MERGE_LOUP32(IPC_GET_ARG1(*call), IPC_GET_ARG2(*call)); |
| |
| keys[0] = call->in_phone_hash; |
| |
| link = hash_table_find(&phone_to_id, keys); |
| if (link != NULL) |
| return EEXISTS; |
| |
| e = (p2i_entry_t *) malloc(sizeof(p2i_entry_t)); |
| if (e == NULL) |
| return ENOMEM; |
| |
| ht = (hashed_task_t *) malloc(sizeof(hashed_task_t)); |
| if (ht == NULL) |
| return ENOMEM; |
| |
| /* Insert to phone-to-id map. */ |
| |
| link_initialize(&e->link); |
| e->phash = call->in_phone_hash; |
| e->id = id; |
| hash_table_insert(&phone_to_id, keys, &e->link); |
| |
| /* Insert to main table. */ |
| |
| keys[0] = LOWER32(id); |
| keys[1] = UPPER32(id); |
| |
| link_initialize(&ht->link); |
| ht->id = id; |
| ht->finished = false; |
| ht->have_rval = false; |
| ht->retval = -1; |
| hash_table_insert(&task_hash_table, keys, &ht->link); |
| |
| return EOK; |
| } |
| |
| int ns_task_retval(ipc_call_t *call) |
| { |
| task_id_t id; |
| unsigned long keys[2]; |
| int rc; |
| |
| rc = get_id_by_phone(call->in_phone_hash, &id); |
| if (rc != EOK) |
| return rc; |
| |
| keys[0] = LOWER32(id); |
| keys[1] = UPPER32(id); |
| |
| link_t *link = hash_table_find(&task_hash_table, keys); |
| hashed_task_t *ht = (link != NULL) ? |
| hash_table_get_instance(link, hashed_task_t, link) : NULL; |
| |
| if ((ht == NULL) || ht->finished) |
| return EINVAL; |
| |
| ht->finished = true; |
| ht->have_rval = true; |
| ht->retval = IPC_GET_ARG1(*call); |
| |
| return EOK; |
| } |
| |
| int ns_task_disconnect(ipc_call_t *call) |
| { |
| unsigned long keys[2]; |
| task_id_t id; |
| int rc; |
| |
| rc = get_id_by_phone(call->in_phone_hash, &id); |
| if (rc != EOK) |
| return rc; |
| |
| /* Delete from phone-to-id map. */ |
| keys[0] = call->in_phone_hash; |
| hash_table_remove(&phone_to_id, keys, 1); |
| |
| /* Mark task as finished. */ |
| keys[0] = LOWER32(id); |
| keys[1] = UPPER32(id); |
| |
| link_t *link = hash_table_find(&task_hash_table, keys); |
| hashed_task_t *ht = |
| hash_table_get_instance(link, hashed_task_t, link); |
| if (ht == NULL) |
| return EOK; |
| |
| ht->finished = true; |
| |
| return EOK; |
| } |
| |
| static int get_id_by_phone(ipcarg_t phone_hash, task_id_t *id) |
| { |
| unsigned long keys[1]; |
| link_t *link; |
| p2i_entry_t *e; |
| |
| keys[0] = phone_hash; |
| link = hash_table_find(&phone_to_id, keys); |
| if (link == NULL) |
| return ENOENT; |
| |
| e = hash_table_get_instance(link, p2i_entry_t, link); |
| *id = e->id; |
| |
| return EOK; |
| } |
| |
| /** |
| * @} |
| */ |