1 /* SPDX-License-Identifier: (GPL-2.0-only or LGPL-2.1-only)
3 * lttng-context-need-reschedule.c
5 * LTTng need_reschedule context.
7 * Copyright (C) 2009-2015 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
10 #include <linux/module.h>
11 #include <linux/slab.h>
12 #include <linux/sched.h>
13 #include <linux/irqflags.h>
14 #include <lttng/events.h>
15 #include <lttng/events-internal.h>
16 #include <ringbuffer/frontend_types.h>
17 #include <wrapper/vmalloc.h>
18 #include <lttng/tracer.h>
21 size_t need_reschedule_get_size(void *priv
, struct lttng_kernel_probe_ctx
*probe_ctx
, size_t offset
)
25 size
+= lib_ring_buffer_align(offset
, lttng_alignof(uint8_t));
26 size
+= sizeof(uint8_t);
31 void need_reschedule_record(void *priv
, struct lttng_kernel_probe_ctx
*probe_ctx
,
32 struct lttng_kernel_ring_buffer_ctx
*ctx
,
33 struct lttng_kernel_channel_buffer
*chan
)
35 uint8_t need_reschedule
= test_tsk_need_resched(current
);
37 chan
->ops
->event_write(ctx
, &need_reschedule
, sizeof(need_reschedule
), lttng_alignof(need_reschedule
));
41 void need_reschedule_get_value(void *priv
,
42 struct lttng_kernel_probe_ctx
*lttng_probe_ctx
,
43 struct lttng_ctx_value
*value
)
45 value
->u
.s64
= test_tsk_need_resched(current
);;
48 static const struct lttng_kernel_ctx_field
*ctx_field
= lttng_kernel_static_ctx_field(
49 lttng_kernel_static_event_field("need_reschedule",
50 lttng_kernel_static_type_integer_from_type(uint8_t, __BYTE_ORDER
, 10),
52 need_reschedule_get_size
,
53 need_reschedule_record
,
54 need_reschedule_get_value
,
57 int lttng_add_need_reschedule_to_ctx(struct lttng_kernel_ctx
**ctx
)
61 if (lttng_kernel_find_context(*ctx
, ctx_field
->event_field
->name
))
63 ret
= lttng_kernel_context_append(ctx
, ctx_field
);
64 wrapper_vmalloc_sync_mappings();
67 EXPORT_SYMBOL_GPL(lttng_add_need_reschedule_to_ctx
);