--- /dev/null
+/*
+ * ltt-ring-buffer-client.c
+ *
+ * Copyright (C) 2010 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ *
+ * LTTng lib ring buffer client.
+ *
+ * Dual LGPL v2.1/GPL v2 license.
+ */
+
+#include <linux/module.h>
+#include "ltt-tracer.h"
+
+struct ring_buffer_priv {
+ struct dentry *dentry;
+}
+
+struct channel_priv {
+ struct ltt_trace *trace;
+ struct ring_buffer_priv *buf;
+};
+
+static const struct lib_ring_buffer_config client_config;
+
+static u64 client_ring_buffer_clock_read(struct channel *chan)
+{
+ return lib_ring_buffer_clock_read(chan);
+}
+
+size_t client_record_header_size(const struct lib_ring_buffer_config *config,
+ struct channel *chan, size_t offset,
+ size_t data_size,
+ size_t *pre_header_padding,
+ unsigned int rflags,
+ struct lib_ring_buffer_ctx *ctx)
+{
+ return record_header_size(config, chan, offset, data_size,
+ pre_header_padding, rflags, ctx);
+}
+
+/**
+ * client_subbuffer_header_size - called on buffer-switch to a new sub-buffer
+ *
+ * Return header size without padding after the structure. Don't use packed
+ * structure because gcc generates inefficient code on some architectures
+ * (powerpc, mips..)
+ */
+static size_t client_subbuffer_header_size(void)
+{
+ return offsetof(struct subbuffer_header, header_end);
+}
+
+static void client_buffer_begin(struct lib_ring_buffer *buf, u64 tsc,
+ unsigned int subbuf_idx)
+{
+ struct channel *chan = buf->backend.chan;
+ struct subbuffer_header *header =
+ (struct subbuffer_header *)
+ lib_ring_buffer_offset_address(&buf->backend,
+ subbuf_idx * chan->backend.subbuf_size);
+
+ header->cycle_count_begin = tsc;
+ header->data_size = 0xFFFFFFFF; /* for debugging */
+ write_trace_header(chan->backend.priv, header);
+}
+
+/*
+ * offset is assumed to never be 0 here : never deliver a completely empty
+ * subbuffer. data_size is between 1 and subbuf_size.
+ */
+static void client_buffer_end(struct lib_ring_buffer *buf, u64 tsc,
+ unsigned int subbuf_idx, unsigned long data_size)
+{
+ struct channel *chan = buf->backend.chan;
+ struct subbuffer_header *header =
+ (struct subbuffer_header *)
+ lib_ring_buffer_offset_address(&buf->backend,
+ subbuf_idx * chan->backend.subbuf_size);
+ unsigned long records_lost = 0;
+
+ header->data_size = data_size;
+ header->subbuf_size = PAGE_ALIGN(data_size);
+ header->cycle_count_end = tsc;
+ records_lost += lib_ring_buffer_get_records_lost_full(&client_config, buf);
+ records_lost += lib_ring_buffer_get_records_lost_wrap(&client_config, buf);
+ records_lost += lib_ring_buffer_get_records_lost_big(&client_config, buf);
+ header->events_lost = records_lost;
+ header->subbuf_corrupt = 0; /* deprecated */
+}
+
+static int client_buffer_create(struct lib_ring_buffer *buf, void *priv,
+ int cpu, const char *name)
+{
+ struct channel_priv *chan_priv = priv;
+ struct ring_buffer_priv *buf_priv;
+ struct dentry *trace_dentry;
+ char *tmpname;
+ int ret = 0;
+
+ if (client_config.alloc == RING_BUFFER_ALLOC_PER_CPU)
+ buf_priv = per_cpu_ptr(chan_priv->buf, cpu);
+ else
+ buf_priv = chan_priv->buf;
+
+ tmpname = kzalloc(NAME_MAX + 1, GFP_KERNEL);
+ if (!tmpname) {
+ ret = -ENOMEM;
+ goto end;
+ }
+
+ snprintf(tmpname, NAME_MAX, "%s%s_%d",
+ (client_config.mode == RING_BUFFER_OVERWRITE) ? : "",
+ name, cpu);
+
+ trace_dentry = chan_priv->trace->dentry.trace_root;
+ buf_priv->dentry = debugfs_create_file(tmpname, S_IRUSR, trace_dentry,
+ buf,
+ &lib_ring_buffer_file_operations);
+ if (!buf_priv->dentry) {
+ ret = -ENOMEM;
+ goto free_name;
+ }
+free_name:
+ kfree(tmpname);
+end:
+ return ret;
+}
+
+static void client_buffer_finalize(struct lib_ring_buffer *buf, void *priv, int cpu)
+{
+ struct channel_priv *chan_priv = priv;
+ struct lib_ring_buffer_priv *buf_priv;
+
+ if (client_config.alloc == RING_BUFFER_ALLOC_PER_CPU)
+ buf_priv = per_cpu_ptr(chan_priv->buf, cpu);
+ else
+ buf_priv = chan_priv->buf;
+
+ debugfs_remove(buf_priv->dentry);
+}
+
+static const struct lib_ring_buffer_config client_config = {
+ .cb.ring_buffer_clock_read = client_ring_buffer_clock_read,
+ .cb.record_header_size = client_record_header_size,
+ .cb.subbuffer_header_size = client_subbuffer_header_size,
+ .cb.buffer_begin = client_buffer_begin,
+ .cb.buffer_end = client_buffer_end,
+ .cb.buffer_create = client_buffer_create,
+ .cb.buffer_finalize = client_buffer_finalize,
+
+ .tsc_bits = 32,
+ .alloc = RING_BUFFER_ALLOC_PER_CPU,
+ .sync = RING_BUFFER_SYNC_PER_CPU,
+ .mode = RING_BUFFER_OVERWRITE,
+#ifdef RING_BUFFER_ALIGN
+ .align = RING_BUFFER_NATURAL,
+#else
+ .align = RING_BUFFER_PACKED,
+#endif
+ .backend = RING_BUFFER_PAGE,
+ .output = RING_BUFFER_SPLICE,
+ .oops = RING_BUFFER_OOPS_CONSISTENCY,
+ .ipi = RING_BUFFER_IPI_BARRIER,
+ .wakeup = RING_BUFFER_WAKEUP_BY_TIMER,
+};
+
+struct channel *ltt_channel_create(const char *name, struct ltt_trace *trace,
+ void *buf_addr,
+ size_t subbuf_size, size_t num_subbuf,
+ unsigned int switch_timer_interval,
+ unsigned int read_timer_interval)
+{
+ struct channel *chan;
+ struct chan_priv *chan_priv;
+
+ chan_priv = kzalloc(sizeof(struct chan_priv), GFP_KERNEL);
+ if (!chan_priv)
+ return NULL;
+ if (client_config.alloc == RING_BUFFER_ALLOC_PER_CPU) {
+ chan_priv->buf = alloc_percpu(struct lib_ring_buffer_priv);
+ memset(chan_priv->buf, 0, sizeof(*chan_priv->buf));
+ } else
+ chan_priv->buf = kzalloc(sizeof(*chan_priv->buf), GFP_KERNEL)
+ if (!channel_priv->buf)
+ goto free_chan_priv;
+ chan_priv->trace = trace;
+ chan = channel_create(&client_config, name, chan_priv, buf_addr,
+ subbuf_size, num_subbuf, switch_timer_interval,
+ read_timer_interval);
+ if (!chan)
+ goto free_buf_priv;
+ return chan;
+
+free_buf_priv:
+ if (client_config.alloc == RING_BUFFER_ALLOC_PER_CPU)
+ free_percpu(chan_priv->buf);
+ else
+ kfree(chan_priv->buf);
+free_chan_priv:
+ kfree(chan_priv);
+ return NULL;
+}
+
+void ltt_channel_destroy(struct channel *chan)
+{
+ struct chan_priv *chan_priv = channel_get_private(chan);
+
+ channel_destroy(chan);
+ if (client_config.alloc == RING_BUFFER_ALLOC_PER_CPU)
+ free_percpu(chan_priv->buf);
+ else
+ kfree(chan_priv->buf);
+ kfree(chan_priv);
+}
+
+static void ltt_relay_remove_dirs(struct ltt_trace *trace)
+{
+#if 0
+ ltt_ascii_remove_dir(trace);
+#endif //0
+ debugfs_remove(trace->dentry.trace_root);
+}
+
+static int ltt_relay_create_dirs(struct ltt_trace *new_trace)
+{
+ struct dentry *ltt_root_dentry;
+ int ret;
+
+ ltt_root_dentry = get_ltt_root();
+ if (!ltt_root_dentry)
+ return ENOENT;
+
+ new_trace->dentry.trace_root = debugfs_create_dir(new_trace->trace_name,
+ ltt_root_dentry);
+ put_ltt_root();
+ if (new_trace->dentry.trace_root == NULL) {
+ printk(KERN_ERR "LTT : Trace directory name %s already taken\n",
+ new_trace->trace_name);
+ return EEXIST;
+ }
+#if 0
+ ret = ltt_ascii_create_dir(new_trace);
+ if (ret)
+ printk(KERN_WARNING "LTT : Unable to create ascii output file "
+ "for trace %s\n", new_trace->trace_name);
+#endif //0
+ return 0;
+}
+static struct ltt_transport ltt_relay_transport = {
+ .name = "relay",
+ .owner = THIS_MODULE,
+ .ops = {
+ .create_dirs = ltt_relay_create_dirs,
+ .remove_dirs = ltt_relay_remove_dirs,
+ },
+};
+
+int __init ltt_ring_buffer_client_init(void)
+{
+ printk(KERN_INFO "LTT : ltt ring buffer client init\n");
+ ltt_transport_register(<t_relay_transport);
+ return 0;
+}
+
+void __exit ltt_ring_buffer_client_exit(void)
+{
+ printk(KERN_INFO "LTT : ltt ring buffer client exit\n");
+ ltt_transport_unregister(<t_relay_transport);
+}
+
+MODULE_LICENSE("GPL and additional rights");
+MODULE_AUTHOR("Mathieu Desnoyers");
+MODULE_DESCRIPTION("LTTng Ring Buffer Client");
projects / lttng-modules.git / blobdiff