+++ /dev/null
-/*
- * lttng-context.c
- *
- * LTTng trace/channel/event context management.
- *
- * Copyright (C) 2011-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; only
- * version 2.1 of the License.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-#include <linux/module.h>
-#include <linux/list.h>
-#include <linux/mutex.h>
-#include <linux/slab.h>
-#include "wrapper/vmalloc.h" /* for wrapper_vmalloc_sync_all() */
-#include "lttng-events.h"
-#include "lttng-tracer.h"
-
-/*
- * The filter implementation requires that two consecutive "get" for the
- * same context performed by the same thread return the same result.
- */
-
-/*
- * Static array of contexts, for $ctx filters.
- */
-struct lttng_ctx *lttng_static_ctx;
-
-int lttng_find_context(struct lttng_ctx *ctx, const char *name)
-{
- unsigned int i;
-
- for (i = 0; i < ctx->nr_fields; i++) {
- /* Skip allocated (but non-initialized) contexts */
- if (!ctx->fields[i].event_field.name)
- continue;
- if (!strcmp(ctx->fields[i].event_field.name, name))
- return 1;
- }
- return 0;
-}
-EXPORT_SYMBOL_GPL(lttng_find_context);
-
-int lttng_get_context_index(struct lttng_ctx *ctx, const char *name)
-{
- unsigned int i;
- const char *subname;
-
- if (!ctx)
- return -1;
- if (strncmp(name, "$ctx.", strlen("$ctx.")) == 0) {
- subname = name + strlen("$ctx.");
- } else {
- subname = name;
- }
- for (i = 0; i < ctx->nr_fields; i++) {
- /* Skip allocated (but non-initialized) contexts */
- if (!ctx->fields[i].event_field.name)
- continue;
- if (!strcmp(ctx->fields[i].event_field.name, subname))
- return i;
- }
- return -1;
-}
-EXPORT_SYMBOL_GPL(lttng_get_context_index);
-
-/*
- * Note: as we append context information, the pointer location may change.
- */
-struct lttng_ctx_field *lttng_append_context(struct lttng_ctx **ctx_p)
-{
- struct lttng_ctx_field *field;
- struct lttng_ctx *ctx;
-
- if (!*ctx_p) {
- *ctx_p = kzalloc(sizeof(struct lttng_ctx), GFP_KERNEL);
- if (!*ctx_p)
- return NULL;
- (*ctx_p)->largest_align = 1;
- }
- ctx = *ctx_p;
- if (ctx->nr_fields + 1 > ctx->allocated_fields) {
- struct lttng_ctx_field *new_fields;
-
- ctx->allocated_fields = max_t(size_t, 1, 2 * ctx->allocated_fields);
- new_fields = kzalloc(ctx->allocated_fields * sizeof(struct lttng_ctx_field), GFP_KERNEL);
- if (!new_fields)
- return NULL;
- if (ctx->fields)
- memcpy(new_fields, ctx->fields, sizeof(*ctx->fields) * ctx->nr_fields);
- kfree(ctx->fields);
- ctx->fields = new_fields;
- }
- field = &ctx->fields[ctx->nr_fields];
- ctx->nr_fields++;
- return field;
-}
-EXPORT_SYMBOL_GPL(lttng_append_context);
-
-/*
- * lttng_context_update() should be called at least once between context
- * modification and trace start.
- */
-void lttng_context_update(struct lttng_ctx *ctx)
-{
- int i;
- size_t largest_align = 8; /* in bits */
-
- for (i = 0; i < ctx->nr_fields; i++) {
- struct lttng_type *type;
- size_t field_align = 8;
-
- type = &ctx->fields[i].event_field.type;
- switch (type->atype) {
- case atype_integer:
- field_align = type->u.basic.integer.alignment;
- break;
- case atype_array:
- {
- struct lttng_basic_type *btype;
-
- btype = &type->u.array.elem_type;
- switch (btype->atype) {
- case atype_integer:
- field_align = btype->u.basic.integer.alignment;
- break;
- case atype_string:
- break;
-
- case atype_array:
- case atype_sequence:
- default:
- WARN_ON_ONCE(1);
- break;
- }
- break;
- }
- case atype_sequence:
- {
- struct lttng_basic_type *btype;
-
- btype = &type->u.sequence.length_type;
- switch (btype->atype) {
- case atype_integer:
- field_align = btype->u.basic.integer.alignment;
- break;
-
- case atype_string:
- case atype_array:
- case atype_sequence:
- default:
- WARN_ON_ONCE(1);
- break;
- }
-
- btype = &type->u.sequence.elem_type;
- switch (btype->atype) {
- case atype_integer:
- field_align = max_t(size_t,
- field_align,
- btype->u.basic.integer.alignment);
- break;
-
- case atype_string:
- break;
-
- case atype_array:
- case atype_sequence:
- default:
- WARN_ON_ONCE(1);
- break;
- }
- break;
- }
- case atype_string:
- break;
-
- case atype_enum:
- default:
- WARN_ON_ONCE(1);
- break;
- }
- largest_align = max_t(size_t, largest_align, field_align);
- }
- ctx->largest_align = largest_align >> 3; /* bits to bytes */
-}
-
-/*
- * Remove last context field.
- */
-void lttng_remove_context_field(struct lttng_ctx **ctx_p,
- struct lttng_ctx_field *field)
-{
- struct lttng_ctx *ctx;
-
- ctx = *ctx_p;
- ctx->nr_fields--;
- WARN_ON_ONCE(&ctx->fields[ctx->nr_fields] != field);
- memset(&ctx->fields[ctx->nr_fields], 0, sizeof(struct lttng_ctx_field));
-}
-EXPORT_SYMBOL_GPL(lttng_remove_context_field);
-
-void lttng_destroy_context(struct lttng_ctx *ctx)
-{
- int i;
-
- if (!ctx)
- return;
- for (i = 0; i < ctx->nr_fields; i++) {
- if (ctx->fields[i].destroy)
- ctx->fields[i].destroy(&ctx->fields[i]);
- }
- kfree(ctx->fields);
- kfree(ctx);
-}
-
-int lttng_context_init(void)
-{
- int ret;
-
- ret = lttng_add_hostname_to_ctx(<tng_static_ctx);
- if (ret) {
- printk(KERN_WARNING "Cannot add context lttng_add_hostname_to_ctx");
- }
- ret = lttng_add_nice_to_ctx(<tng_static_ctx);
- if (ret) {
- printk(KERN_WARNING "Cannot add context lttng_add_nice_to_ctx");
- }
- ret = lttng_add_pid_to_ctx(<tng_static_ctx);
- if (ret) {
- printk(KERN_WARNING "Cannot add context lttng_add_pid_to_ctx");
- }
- ret = lttng_add_ppid_to_ctx(<tng_static_ctx);
- if (ret) {
- printk(KERN_WARNING "Cannot add context lttng_add_ppid_to_ctx");
- }
- ret = lttng_add_prio_to_ctx(<tng_static_ctx);
- if (ret) {
- printk(KERN_WARNING "Cannot add context lttng_add_prio_to_ctx");
- }
- ret = lttng_add_procname_to_ctx(<tng_static_ctx);
- if (ret) {
- printk(KERN_WARNING "Cannot add context lttng_add_procname_to_ctx");
- }
- ret = lttng_add_tid_to_ctx(<tng_static_ctx);
- if (ret) {
- printk(KERN_WARNING "Cannot add context lttng_add_tid_to_ctx");
- }
- ret = lttng_add_vppid_to_ctx(<tng_static_ctx);
- if (ret) {
- printk(KERN_WARNING "Cannot add context lttng_add_vppid_to_ctx");
- }
- ret = lttng_add_vtid_to_ctx(<tng_static_ctx);
- if (ret) {
- printk(KERN_WARNING "Cannot add context lttng_add_vtid_to_ctx");
- }
- ret = lttng_add_vpid_to_ctx(<tng_static_ctx);
- if (ret) {
- printk(KERN_WARNING "Cannot add context lttng_add_vpid_to_ctx");
- }
- ret = lttng_add_cpu_id_to_ctx(<tng_static_ctx);
- if (ret) {
- printk(KERN_WARNING "Cannot add context lttng_add_cpu_id_to_ctx");
- }
- ret = lttng_add_interruptible_to_ctx(<tng_static_ctx);
- if (ret) {
- printk(KERN_WARNING "Cannot add context lttng_add_interruptible_to_ctx");
- }
- ret = lttng_add_need_reschedule_to_ctx(<tng_static_ctx);
- if (ret) {
- printk(KERN_WARNING "Cannot add context lttng_add_need_reschedule_to_ctx");
- }
-#if defined(CONFIG_PREEMPT_RT_FULL) || defined(CONFIG_PREEMPT)
- ret = lttng_add_preemptible_to_ctx(<tng_static_ctx);
- if (ret != -ENOSYS) {
- printk(KERN_WARNING "Cannot add context lttng_add_preemptible_to_ctx");
- }
-#endif
-#ifdef CONFIG_PREEMPT_RT_FULL
- ret = lttng_add_migratable_to_ctx(<tng_static_ctx);
- if (ret != -ENOSYS) {
- printk(KERN_WARNING "Cannot add context lttng_add_migratable_to_ctx");
- }
-#endif
- /* TODO: perf counters for filtering */
- return 0;
-}
-
-void lttng_context_exit(void)
-{
- lttng_destroy_context(lttng_static_ctx);
- lttng_static_ctx = NULL;
-}
projects / lttng-modules.git / blobdiff