X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=liblttng-ust%2Flttng-context.c;h=e408defc9893fc038d0901126cc844143c19fca3;hb=HEAD;hp=5637028bed1bdd35d38715ad68afc33673652c50;hpb=218deb69baab57ee2f6728eef18e84697f21197b;p=lttng-ust.git diff --git a/liblttng-ust/lttng-context.c b/liblttng-ust/lttng-context.c deleted file mode 100644 index 5637028b..00000000 --- a/liblttng-ust/lttng-context.c +++ /dev/null @@ -1,514 +0,0 @@ -/* - * lttng-context.c - * - * LTTng UST trace/channel/event context management. - * - * Copyright (C) 2011 Mathieu Desnoyers - * - * 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 - */ - -#define _LGPL_SOURCE -#include -#include -#include -#include -#include -#include -#include -#include -#include - -/* - * The filter implementation requires that two consecutive "get" for the - * same context performed by the same thread return the same result. - */ - -int lttng_find_context(struct lttng_ctx *ctx, const char *name) -{ - unsigned int i; - const char *subname; - - if (strncmp(name, "$ctx.", strlen("$ctx.")) == 0) { - subname = name + strlen("$ctx."); - } else { - subname = name; - } - for (i = 0; i < ctx->nr_fields; i++) { - /* Skip allocated (but non-initialized) contexts */ - if (!ctx->fields[i].event_field.name) - continue; - if (!strcmp(ctx->fields[i].event_field.name, subname)) - return 1; - } - return 0; -} - -int lttng_get_context_index(struct lttng_ctx *ctx, const char *name) -{ - unsigned int i; - const char *subname; - - if (!ctx) - return -1; - if (strncmp(name, "$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; -} - -static int lttng_find_context_provider(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 (!strncmp(ctx->fields[i].event_field.name, name, - strlen(name))) - return 1; - } - return 0; -} - -/* - * 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 = zmalloc(sizeof(struct lttng_ctx)); - 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 = zmalloc(ctx->allocated_fields * sizeof(struct lttng_ctx_field)); - if (!new_fields) - return NULL; - if (ctx->fields) - memcpy(new_fields, ctx->fields, sizeof(*ctx->fields) * ctx->nr_fields); - free(ctx->fields); - ctx->fields = new_fields; - } - field = &ctx->fields[ctx->nr_fields]; - ctx->nr_fields++; - return field; -} - -int lttng_context_add_rcu(struct lttng_ctx **ctx_p, - const struct lttng_ctx_field *f) -{ - struct lttng_ctx *old_ctx = *ctx_p, *new_ctx = NULL; - struct lttng_ctx_field *new_fields = NULL; - struct lttng_ctx_field *nf; - - if (old_ctx) { - new_ctx = zmalloc(sizeof(struct lttng_ctx)); - if (!new_ctx) - return -ENOMEM; - *new_ctx = *old_ctx; - new_fields = zmalloc(new_ctx->allocated_fields - * sizeof(struct lttng_ctx_field)); - if (!new_fields) { - free(new_ctx); - return -ENOMEM; - } - memcpy(new_fields, old_ctx->fields, - sizeof(*old_ctx->fields) * old_ctx->nr_fields); - new_ctx->fields = new_fields; - } - nf = lttng_append_context(&new_ctx); - if (!nf) { - free(new_fields); - free(new_ctx); - return -ENOMEM; - } - *nf = *f; - lttng_context_update(new_ctx); - rcu_assign_pointer(*ctx_p, new_ctx); - synchronize_trace(); - if (old_ctx) { - free(old_ctx->fields); - free(old_ctx); - } - return 0; -} - -/* - * 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.integer.alignment; - break; - case atype_array: - { - struct lttng_basic_type *btype; - - btype = &type->u.legacy.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_array_nestable: - case atype_sequence: - case atype_sequence_nestable: - default: - WARN_ON_ONCE(1); - break; - } - break; - } - case atype_array_nestable: - { - const struct lttng_type *nested_type; - - nested_type = type->u.array_nestable.elem_type; - switch (nested_type->atype) { - case atype_integer: - field_align = nested_type->u.integer.alignment; - break; - case atype_string: - break; - - case atype_array: - case atype_array_nestable: - case atype_sequence: - case atype_sequence_nestable: - default: - WARN_ON_ONCE(1); - break; - } - field_align = max_t(size_t, field_align, - type->u.array_nestable.alignment); - break; - } - case atype_sequence: - { - struct lttng_basic_type *btype; - - btype = &type->u.legacy.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_array_nestable: - case atype_sequence: - case atype_sequence_nestable: - default: - WARN_ON_ONCE(1); - break; - } - - btype = &type->u.legacy.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_array_nestable: - case atype_sequence: - case atype_sequence_nestable: - default: - WARN_ON_ONCE(1); - break; - } - break; - } - case atype_sequence_nestable: - { - const struct lttng_type *nested_type; - - nested_type = type->u.sequence_nestable.elem_type; - switch (nested_type->atype) { - case atype_integer: - field_align = nested_type->u.integer.alignment; - break; - - case atype_string: - break; - - case atype_array: - case atype_array_nestable: - case atype_sequence: - case atype_sequence_nestable: - default: - WARN_ON_ONCE(1); - break; - } - field_align = max_t(size_t, field_align, - type->u.sequence_nestable.alignment); - break; - } - case atype_string: - break; - case atype_dynamic: - break; - case atype_enum: - case atype_enum_nestable: - 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--; - assert(&ctx->fields[ctx->nr_fields] == field); - assert(field->field_name == NULL); - memset(&ctx->fields[ctx->nr_fields], 0, sizeof(struct lttng_ctx_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]); - free(ctx->fields[i].field_name); - } - free(ctx->fields); - free(ctx); -} - -/* - * Can be safely performed concurrently with tracing using the struct - * lttng_ctx. Using RCU update. Needs to match RCU read-side handling of - * contexts. - * - * This does not allow adding, removing, or changing typing of the - * contexts, since this needs to stay invariant for metadata. However, - * it allows updating the handlers associated with all contexts matching - * a provider (by name) while tracing is using it, in a way that ensures - * a single RCU read-side critical section see either all old, or all - * new handlers. - */ -int lttng_ust_context_set_provider_rcu(struct lttng_ctx **_ctx, - const char *name, - size_t (*get_size)(struct lttng_ctx_field *field, size_t offset), - void (*record)(struct lttng_ctx_field *field, - struct lttng_ust_lib_ring_buffer_ctx *ctx, - struct lttng_channel *chan), - void (*get_value)(struct lttng_ctx_field *field, - struct lttng_ctx_value *value)) -{ - int i, ret; - struct lttng_ctx *ctx = *_ctx, *new_ctx; - struct lttng_ctx_field *new_fields; - - if (!ctx || !lttng_find_context_provider(ctx, name)) - return 0; - /* - * We have at least one instance of context for the provider. - */ - new_ctx = zmalloc(sizeof(*new_ctx)); - if (!new_ctx) - return -ENOMEM; - *new_ctx = *ctx; - new_fields = zmalloc(sizeof(*new_fields) * ctx->allocated_fields); - if (!new_fields) { - ret = -ENOMEM; - goto field_error; - } - memcpy(new_fields, ctx->fields, - sizeof(*new_fields) * ctx->allocated_fields); - for (i = 0; i < ctx->nr_fields; i++) { - if (strncmp(new_fields[i].event_field.name, - name, strlen(name)) != 0) - continue; - new_fields[i].get_size = get_size; - new_fields[i].record = record; - new_fields[i].get_value = get_value; - } - new_ctx->fields = new_fields; - rcu_assign_pointer(*_ctx, new_ctx); - synchronize_trace(); - free(ctx->fields); - free(ctx); - return 0; - -field_error: - free(new_ctx); - return ret; -} - -int lttng_session_context_init(struct lttng_ctx **ctx) -{ - int ret; - - ret = lttng_add_pthread_id_to_ctx(ctx); - if (ret) { - WARN("Cannot add context lttng_add_pthread_id_to_ctx"); - goto error; - } - ret = lttng_add_vtid_to_ctx(ctx); - if (ret) { - WARN("Cannot add context lttng_add_vtid_to_ctx"); - goto error; - } - ret = lttng_add_vpid_to_ctx(ctx); - if (ret) { - WARN("Cannot add context lttng_add_vpid_to_ctx"); - goto error; - } - ret = lttng_add_procname_to_ctx(ctx); - if (ret) { - WARN("Cannot add context lttng_add_procname_to_ctx"); - goto error; - } - ret = lttng_add_cpu_id_to_ctx(ctx); - if (ret) { - WARN("Cannot add context lttng_add_cpu_id_to_ctx"); - goto error; - } - ret = lttng_add_cgroup_ns_to_ctx(ctx); - if (ret) { - WARN("Cannot add context lttng_add_cgroup_ns_to_ctx"); - goto error; - } - ret = lttng_add_ipc_ns_to_ctx(ctx); - if (ret) { - WARN("Cannot add context lttng_add_ipc_ns_to_ctx"); - goto error; - } - ret = lttng_add_mnt_ns_to_ctx(ctx); - if (ret) { - WARN("Cannot add context lttng_add_mnt_ns_to_ctx"); - goto error; - } - ret = lttng_add_net_ns_to_ctx(ctx); - if (ret) { - WARN("Cannot add context lttng_add_net_ns_to_ctx"); - goto error; - } - ret = lttng_add_pid_ns_to_ctx(ctx); - if (ret) { - WARN("Cannot add context lttng_add_pid_ns_to_ctx"); - goto error; - } - ret = lttng_add_user_ns_to_ctx(ctx); - if (ret) { - WARN("Cannot add context lttng_add_user_ns_to_ctx"); - goto error; - } - ret = lttng_add_uts_ns_to_ctx(ctx); - if (ret) { - WARN("Cannot add context lttng_add_uts_ns_to_ctx"); - goto error; - } - ret = lttng_add_vuid_to_ctx(ctx); - if (ret) { - WARN("Cannot add context lttng_add_vuid_to_ctx"); - goto error; - } - ret = lttng_add_veuid_to_ctx(ctx); - if (ret) { - WARN("Cannot add context lttng_add_veuid_to_ctx"); - goto error; - } - ret = lttng_add_vsuid_to_ctx(ctx); - if (ret) { - WARN("Cannot add context lttng_add_vsuid_to_ctx"); - goto error; - } - ret = lttng_add_vgid_to_ctx(ctx); - if (ret) { - WARN("Cannot add context lttng_add_vgid_to_ctx"); - goto error; - } - ret = lttng_add_vegid_to_ctx(ctx); - if (ret) { - WARN("Cannot add context lttng_add_vegid_to_ctx"); - goto error; - } - ret = lttng_add_vsgid_to_ctx(ctx); - if (ret) { - WARN("Cannot add context lttng_add_vsgid_to_ctx"); - goto error; - } - lttng_context_update(*ctx); - return 0; - -error: - lttng_destroy_context(*ctx); - return ret; -} - -/* For backward compatibility. Leave those exported symbols in place. */ -struct lttng_ctx *lttng_static_ctx; - -void lttng_context_init(void) -{ -} - -void lttng_context_exit(void) -{ -}