+++ /dev/null
-/* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only)
- *
- * lttng-context-prio.c
- *
- * LTTng priority context.
- *
- * Copyright (C) 2009-2012 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
- */
-
-#include <linux/module.h>
-#include <linux/slab.h>
-#include <linux/sched.h>
-#include <lttng/events.h>
-#include <ringbuffer/frontend_types.h>
-#include <wrapper/vmalloc.h>
-#include <wrapper/kallsyms.h>
-#include <lttng/tracer.h>
-
-static
-int (*wrapper_task_prio_sym)(struct task_struct *t);
-
-int wrapper_task_prio_init(void)
-{
- wrapper_task_prio_sym = (void *) kallsyms_lookup_funcptr("task_prio");
- if (!wrapper_task_prio_sym) {
- printk(KERN_WARNING "LTTng: task_prio symbol lookup failed.\n");
- return -EINVAL;
- }
- return 0;
-}
-
-static
-size_t prio_get_size(size_t offset)
-{
- size_t size = 0;
-
- size += lib_ring_buffer_align(offset, lttng_alignof(int));
- size += sizeof(int);
- return size;
-}
-
-static
-void prio_record(struct lttng_ctx_field *field,
- struct lib_ring_buffer_ctx *ctx,
- struct lttng_channel *chan)
-{
- int prio;
-
- prio = wrapper_task_prio_sym(current);
- lib_ring_buffer_align_ctx(ctx, lttng_alignof(prio));
- chan->ops->event_write(ctx, &prio, sizeof(prio));
-}
-
-static
-void prio_get_value(struct lttng_ctx_field *field,
- struct lttng_probe_ctx *lttng_probe_ctx,
- union lttng_ctx_value *value)
-{
- value->s64 = wrapper_task_prio_sym(current);
-}
-
-int lttng_add_prio_to_ctx(struct lttng_ctx **ctx)
-{
- struct lttng_ctx_field *field;
- int ret;
-
- if (!wrapper_task_prio_sym) {
- ret = wrapper_task_prio_init();
- if (ret)
- return ret;
- }
-
- field = lttng_append_context(ctx);
- if (!field)
- return -ENOMEM;
- if (lttng_find_context(*ctx, "prio")) {
- lttng_remove_context_field(ctx, field);
- return -EEXIST;
- }
- field->event_field.name = "prio";
- field->event_field.type.atype = atype_integer;
- field->event_field.type.u.integer.size = sizeof(int) * CHAR_BIT;
- field->event_field.type.u.integer.alignment = lttng_alignof(int) * CHAR_BIT;
- field->event_field.type.u.integer.signedness = lttng_is_signed_type(int);
- field->event_field.type.u.integer.reverse_byte_order = 0;
- field->event_field.type.u.integer.base = 10;
- field->event_field.type.u.integer.encoding = lttng_encode_none;
- field->get_size = prio_get_size;
- field->record = prio_record;
- field->get_value = prio_get_value;
- lttng_context_update(*ctx);
- wrapper_vmalloc_sync_mappings();
- return 0;
-}
-EXPORT_SYMBOL_GPL(lttng_add_prio_to_ctx);