projects / lttng-modules.git / blame
| Commit | Line | Data |
|---|---|---|
| 9f36eaed MJ |
1 | /* SPDX-License-Identifier: (GPL-2.0 or LGPL-2.1) |
| 2 | * | |
| 79150a49 JD |
3 | * lttng-context-migratable.c |
| 4 | * | |
| 5 | * LTTng migratable context. | |
| 6 | * | |
| 7 | * Copyright (C) 2009-2015 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> | |
| 79150a49 JD |
8 | */ |
| 9 | ||
| 10 | #include <linux/module.h> | |
| 11 | #include <linux/slab.h> | |
| 12 | #include <linux/sched.h> | |
| 13 | #include <linux/irqflags.h> | |
| 241ae9a8 MD |
14 | #include <lttng-events.h> |
| 15 | #include <wrapper/ringbuffer/frontend_types.h> | |
| 16 | #include <wrapper/vmalloc.h> | |
| 17 | #include <lttng-tracer.h> | |
| 79150a49 JD |
18 | |
| 19 | static | |
| 20 | size_t migratable_get_size(size_t offset) | |
| 21 | { | |
| 22 | size_t size = 0; | |
| 23 | ||
| 24 | size += lib_ring_buffer_align(offset, lttng_alignof(uint8_t)); | |
| 25 | size += sizeof(uint8_t); | |
| 26 | return size; | |
| 27 | } | |
| 28 | ||
| 29 | static | |
| 30 | void migratable_record(struct lttng_ctx_field *field, | |
| 31 | struct lib_ring_buffer_ctx *ctx, | |
| 32 | struct lttng_channel *chan) | |
| 33 | { | |
| 4531da84 | 34 | uint8_t migratable = !current->migrate_disable; |
| 79150a49 JD |
35 | |
| 36 | lib_ring_buffer_align_ctx(ctx, lttng_alignof(migratable)); | |
| 37 | chan->ops->event_write(ctx, &migratable, sizeof(migratable)); | |
| 38 | } | |
| 39 | ||
| 40 | static | |
| 41 | void migratable_get_value(struct lttng_ctx_field *field, | |
| 42 | struct lttng_probe_ctx *lttng_probe_ctx, | |
| 43 | union lttng_ctx_value *value) | |
| 44 | { | |
| 4531da84 | 45 | value->s64 = !current->migrate_disable; |
| 79150a49 JD |
46 | } |
| 47 | ||
| 48 | int lttng_add_migratable_to_ctx(struct lttng_ctx **ctx) | |
| 49 | { | |
| 50 | struct lttng_ctx_field *field; | |
| 51 | ||
| 52 | field = lttng_append_context(ctx); | |
| 53 | if (!field) | |
| 54 | return -ENOMEM; | |
| 55 | if (lttng_find_context(*ctx, "migratable")) { | |
| 56 | lttng_remove_context_field(ctx, field); | |
| 57 | return -EEXIST; | |
| 58 | } | |
| 59 | field->event_field.name = "migratable"; | |
| 60 | field->event_field.type.atype = atype_integer; | |
| 61 | field->event_field.type.u.basic.integer.size = sizeof(uint8_t) * CHAR_BIT; | |
| 62 | field->event_field.type.u.basic.integer.alignment = lttng_alignof(uint8_t) * CHAR_BIT; | |
| 63 | field->event_field.type.u.basic.integer.signedness = lttng_is_signed_type(uint8_t); | |
| 64 | field->event_field.type.u.basic.integer.reverse_byte_order = 0; | |
| 65 | field->event_field.type.u.basic.integer.base = 10; | |
| 66 | field->event_field.type.u.basic.integer.encoding = lttng_encode_none; | |
| 67 | field->get_size = migratable_get_size; | |
| 68 | field->record = migratable_record; | |
| 69 | field->get_value = migratable_get_value; | |
| 70 | lttng_context_update(*ctx); | |
| da0fcb14 | 71 | wrapper_vmalloc_sync_mappings(); |
| 79150a49 JD |
72 | return 0; |
| 73 | } | |
| 74 | EXPORT_SYMBOL_GPL(lttng_add_migratable_to_ctx); |