diff options
Diffstat (limited to 'agent/tcf/system/pid-hash.h')
-rw-r--r-- | agent/tcf/system/pid-hash.h | 76 |
1 files changed, 76 insertions, 0 deletions
diff --git a/agent/tcf/system/pid-hash.h b/agent/tcf/system/pid-hash.h new file mode 100644 index 00000000..4843ec8c --- /dev/null +++ b/agent/tcf/system/pid-hash.h @@ -0,0 +1,76 @@ +/******************************************************************************* + * Copyright (c) 2007, 2010 Wind River Systems, Inc. and others. + * All rights reserved. This program and the accompanying materials + * are made available under the terms of the Eclipse Public License v1.0 + * and Eclipse Distribution License v1.0 which accompany this distribution. + * The Eclipse Public License is available at + * http://www.eclipse.org/legal/epl-v10.html + * and the Eclipse Distribution License is available at + * http://www.eclipse.org/org/documents/edl-v10.php. + * You may elect to redistribute this code under either of these licenses. + * + * Contributors: + * Wind River Systems - initial API and implementation + *******************************************************************************/ + +/* + * This is utility module that contains context PID hash table implementation. + * System specific debug context code can use this module to implement context lookup. + */ + +/* TODO: consider splitting the code into two files: some clients might want to reuse PID hash table for context_find_from_pid(), + * but use some other means to implement id2ctx() */ + +#define CONTEXT_PID_HASH_SIZE (32 * MEM_USAGE_FACTOR - 1) +#define CONTEXT_PID_HASH(PID) ((unsigned)(PID) % CONTEXT_PID_HASH_SIZE) + +static LINK context_pid_hash[CONTEXT_PID_HASH_SIZE]; +static size_t pid_hash_link_offset = 0; + +#define ctx2pidlink(ctx) ((LINK *)((char *)(ctx) + pid_hash_link_offset)) +#define pidlink2ctx(lnk) ((Context *)((char *)(lnk) - pid_hash_link_offset)) + +static void link_context(Context * ctx) { + LINK * h = context_pid_hash + CONTEXT_PID_HASH(EXT(ctx)->pid); + + assert(ctx->mem != NULL); + assert(EXT(ctx)->pid != 0); + assert(context_find_from_pid(EXT(ctx)->pid, ctx->parent != NULL) == NULL); + list_add_first(&ctx->ctxl, &context_root); + list_add_first(ctx2pidlink(ctx), h); + ctx->ref_count++; +} + +Context * context_find_from_pid(pid_t pid, int thread) { + LINK * h = context_pid_hash + CONTEXT_PID_HASH(pid); + LINK * l = h->next; + + assert(is_dispatch_thread()); + if (l == NULL) return NULL; + while (l != h) { + Context * ctx = pidlink2ctx(l); + if (EXT(ctx)->pid == pid && + (ctx->parent != NULL) == (thread != 0)) return ctx; + l = l->next; + } + return NULL; +} + +Context * id2ctx(const char * id) { + pid_t parent = 0; + pid_t pid = id2pid(id, &parent); + if (pid == 0) return NULL; + return context_find_from_pid(pid, parent != 0); +} + +static void pid_hash_context_exited(Context * ctx, void * args) { + list_remove(ctx2pidlink(ctx)); +} + +static void ini_context_pid_hash(void) { + int i; + static ContextEventListener l = { NULL, pid_hash_context_exited }; + for (i = 0; i < CONTEXT_PID_HASH_SIZE; i++) list_init(context_pid_hash + i); + pid_hash_link_offset = context_extension(sizeof(LINK)); + add_context_event_listener(&l, NULL); +} |