Remove ltt-channels.c. Part of LTTng kernel tree.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

diff --git a/ltt-channels.c b/ltt-channels.c
deleted file mode 100644 (file)
index c1cee26..0000000
--- a/ltt-channels.c
+++ /dev/null
@@ -1,388 +0,0 @@
- /*
- * ltt/ltt-channels.c
- *
- * (C) Copyright 2008 - Mathieu Desnoyers (mathieu.desnoyers@polymtl.ca)
- *
- * LTTng channel management.
- *
- * Author:
- *     Mathieu Desnoyers (mathieu.desnoyers@polymtl.ca)
- *
- * Dual LGPL v2.1/GPL v2 license.
- */
-
-#include <linux/module.h>
-#include <linux/mutex.h>
-#include <linux/slab.h>
-#include <linux/vmalloc.h>
-#include <linux/ltt-channels.h>
-
-/*
- * ltt_channel_mutex may be nested inside the LTT trace mutex.
- * ltt_channel_mutex mutex may be nested inside markers mutex.
- */
-static DEFINE_MUTEX(ltt_channel_mutex);
-static LIST_HEAD(ltt_channels);
-/*
- * Index of next channel in array. Makes sure that as long as a trace channel is
- * allocated, no array index will be re-used when a channel is freed and then
- * another channel is allocated. This index is cleared and the array indexeds
- * get reassigned when the index_kref goes back to 0, which indicates that no
- * more trace channels are allocated.
- */
-static unsigned int free_index;
-/* index_kref is protected by both ltt_channel_mutex and lock_markers */
-static struct kref index_kref; /* Keeps track of allocated trace channels */
-
-static struct ltt_channel_setting *lookup_channel(const char *name)
-{
-       struct ltt_channel_setting *iter;
-
-       list_for_each_entry(iter, &ltt_channels, list)
-               if (strcmp(name, iter->name) == 0)
-                       return iter;
-       return NULL;
-}
-
-/*
- * Must be called when channel refcount falls to 0 _and_ also when the last
- * trace is freed. This function is responsible for compacting the channel and
- * event IDs when no users are active.
- *
- * Called with lock_markers() and channels mutex held.
- */
-static void release_channel_setting(struct kref *kref)
-{
-       struct ltt_channel_setting *setting = container_of(kref,
-               struct ltt_channel_setting, kref);
-       struct ltt_channel_setting *iter;
-
-       if (atomic_read(&index_kref.refcount) == 0
-           && atomic_read(&setting->kref.refcount) == 0) {
-               list_del(&setting->list);
-               kfree(setting);
-
-               free_index = 0;
-               list_for_each_entry(iter, &ltt_channels, list) {
-                       iter->index = free_index++;
-                       iter->free_event_id = 0;
-               }
-       }
-}
-
-/*
- * Perform channel index compaction when the last trace channel is freed.
- *
- * Called with lock_markers() and channels mutex held.
- */
-static void release_trace_channel(struct kref *kref)
-{
-       struct ltt_channel_setting *iter, *n;
-
-       list_for_each_entry_safe(iter, n, &ltt_channels, list)
-               release_channel_setting(&iter->kref);
-       if (atomic_read(&index_kref.refcount) == 0)
-               markers_compact_event_ids();
-}
-
-/*
- * ltt_channel_trace_ref :  Is there an existing trace session ?
- *
- * Must be called with lock_markers() held.
- */
-int ltt_channels_trace_ref(void)
-{
-       return !!atomic_read(&index_kref.refcount);
-}
-EXPORT_SYMBOL_GPL(ltt_channels_trace_ref);
-
-/**
- * ltt_channels_register - Register a trace channel.
- * @name: channel name
- *
- * Uses refcounting.
- */
-int ltt_channels_register(const char *name)
-{
-       struct ltt_channel_setting *setting;
-       int ret = 0;
-
-       mutex_lock(&ltt_channel_mutex);
-       setting = lookup_channel(name);
-       if (setting) {
-               if (atomic_read(&setting->kref.refcount) == 0)
-                       goto init_kref;
-               else {
-                       kref_get(&setting->kref);
-                       goto end;
-               }
-       }
-       setting = kzalloc(sizeof(*setting), GFP_KERNEL);
-       if (!setting) {
-               ret = -ENOMEM;
-               goto end;
-       }
-       list_add(&setting->list, &ltt_channels);
-       strncpy(setting->name, name, PATH_MAX-1);
-       setting->index = free_index++;
-init_kref:
-       kref_init(&setting->kref);
-end:
-       mutex_unlock(&ltt_channel_mutex);
-       return ret;
-}
-EXPORT_SYMBOL_GPL(ltt_channels_register);
-
-/**
- * ltt_channels_unregister - Unregister a trace channel.
- * @name: channel name
- * @compacting: performing compaction
- *
- * Must be called with markers mutex held.
- */
-int ltt_channels_unregister(const char *name, int compacting)
-{
-       struct ltt_channel_setting *setting;
-       int ret = 0;
-
-       if (!compacting)
-               mutex_lock(&ltt_channel_mutex);
-       setting = lookup_channel(name);
-       if (!setting || atomic_read(&setting->kref.refcount) == 0) {
-               ret = -ENOENT;
-               goto end;
-       }
-       kref_put(&setting->kref, release_channel_setting);
-       if (!compacting && atomic_read(&index_kref.refcount) == 0)
-                       markers_compact_event_ids();
-end:
-       if (!compacting)
-               mutex_unlock(&ltt_channel_mutex);
-       return ret;
-}
-EXPORT_SYMBOL_GPL(ltt_channels_unregister);
-
-/**
- * ltt_channels_set_default - Set channel default behavior.
- * @name: default channel name
- * @sb_size: size of the subbuffers
- * @n_sb: number of subbuffers
- */
-int ltt_channels_set_default(const char *name,
-                            unsigned int sb_size,
-                            unsigned int n_sb)
-{
-       struct ltt_channel_setting *setting;
-       int ret = 0;
-
-       mutex_lock(&ltt_channel_mutex);
-       setting = lookup_channel(name);
-       if (!setting || atomic_read(&setting->kref.refcount) == 0) {
-               ret = -ENOENT;
-               goto end;
-       }
-       setting->sb_size = sb_size;
-       setting->n_sb = n_sb;
-end:
-       mutex_unlock(&ltt_channel_mutex);
-       return ret;
-}
-EXPORT_SYMBOL_GPL(ltt_channels_set_default);
-
-/**
- * ltt_channels_get_name_from_index - get channel name from channel index
- * @index: channel index
- *
- * Allows to lookup the channel name given its index. Done to keep the name
- * information outside of each trace channel instance.
- */
-const char *ltt_channels_get_name_from_index(unsigned int index)
-{
-       struct ltt_channel_setting *iter;
-
-       list_for_each_entry(iter, &ltt_channels, list)
-               if (iter->index == index && atomic_read(&iter->kref.refcount))
-                       return iter->name;
-       return NULL;
-}
-EXPORT_SYMBOL_GPL(ltt_channels_get_name_from_index);
-
-static struct ltt_channel_setting *
-ltt_channels_get_setting_from_name(const char *name)
-{
-       struct ltt_channel_setting *iter;
-
-       list_for_each_entry(iter, &ltt_channels, list)
-               if (!strcmp(iter->name, name)
-                   && atomic_read(&iter->kref.refcount))
-                       return iter;
-       return NULL;
-}
-
-/**
- * ltt_channels_get_index_from_name - get channel index from channel name
- * @name: channel name
- *
- * Allows to lookup the channel index given its name. Done to keep the name
- * information outside of each trace channel instance.
- * Returns -1 if not found.
- */
-int ltt_channels_get_index_from_name(const char *name)
-{
-       struct ltt_channel_setting *setting;
-
-       setting = ltt_channels_get_setting_from_name(name);
-       if (setting)
-               return setting->index;
-       else
-               return -1;
-}
-EXPORT_SYMBOL_GPL(ltt_channels_get_index_from_name);
-
-/**
- * ltt_channels_trace_alloc - Allocate channel structures for a trace
- * @sb_size: subbuffer size. 0 uses default.
- * @n_sb: number of subbuffers per per-cpu buffers. 0 uses default.
- * @flags: Default channel flags
- *
- * Use the current channel list to allocate the channels for a trace.
- * Called with trace lock held. Does not perform the trace buffer allocation,
- * because we must let the user overwrite specific channel sizes.
- */
-struct ltt_chan *ltt_channels_trace_alloc(unsigned int *nr_channels,
-                                         int overwrite, int active)
-{
-       struct ltt_chan *chan = NULL;
-       struct ltt_channel_setting *iter;
-
-       lock_markers();
-       mutex_lock(&ltt_channel_mutex);
-       if (!free_index)
-               goto end;
-       if (!atomic_read(&index_kref.refcount))
-               kref_init(&index_kref);
-       else
-               kref_get(&index_kref);
-       *nr_channels = free_index;
-       chan = kzalloc(sizeof(struct ltt_chan) * free_index, GFP_KERNEL);
-       if (!chan)
-               goto end;
-       list_for_each_entry(iter, &ltt_channels, list) {
-               if (!atomic_read(&iter->kref.refcount))
-                       continue;
-               chan[iter->index].a.sb_size = iter->sb_size;
-               chan[iter->index].a.n_sb = iter->n_sb;
-               chan[iter->index].overwrite = overwrite;
-               chan[iter->index].active = active;
-               strncpy(chan[iter->index].a.filename, iter->name, NAME_MAX - 1);
-               chan[iter->index].switch_timer_interval = 0;
-       }
-end:
-       mutex_unlock(&ltt_channel_mutex);
-       unlock_markers();
-       return chan;
-}
-EXPORT_SYMBOL_GPL(ltt_channels_trace_alloc);
-
-/**
- * ltt_channels_trace_free - Free one trace's channels
- * @channels: channels to free
- *
- * Called with trace lock held. The actual channel buffers must be freed before
- * this function is called.
- */
-void ltt_channels_trace_free(struct ltt_chan *channels,
-                            unsigned int nr_channels)
-{
-       lock_markers();
-       mutex_lock(&ltt_channel_mutex);
-       kfree(channels);
-       kref_put(&index_kref, release_trace_channel);
-       mutex_unlock(&ltt_channel_mutex);
-       unlock_markers();
-       marker_update_probes();
-}
-EXPORT_SYMBOL_GPL(ltt_channels_trace_free);
-
-/**
- * ltt_channels_trace_set_timer - set switch timer
- * @channel: channel
- * @interval: interval of timer interrupt, in jiffies. 0 inhibits timer.
- */
-
-void ltt_channels_trace_set_timer(struct ltt_chan *chan,
-                                 unsigned long interval)
-{
-       chan->switch_timer_interval = interval;
-}
-EXPORT_SYMBOL_GPL(ltt_channels_trace_set_timer);
-
-/**
- * _ltt_channels_get_event_id - get next event ID for a marker
- * @channel: channel name
- * @name: event name
- *
- * Returns a unique event ID (for this channel) or < 0 on error.
- * Must be called with channels mutex held.
- */
-int _ltt_channels_get_event_id(const char *channel, const char *name)
-{
-       struct ltt_channel_setting *setting;
-       int ret;
-
-       setting = ltt_channels_get_setting_from_name(channel);
-       if (!setting) {
-               ret = -ENOENT;
-               goto end;
-       }
-       if (strcmp(channel, "metadata") == 0) {
-               if (strcmp(name, "core_marker_id") == 0)
-                       ret = 0;
-               else if (strcmp(name, "core_marker_format") == 0)
-                       ret = 1;
-               else
-                       ret = -ENOENT;
-               goto end;
-       }
-       if (setting->free_event_id == EVENTS_PER_CHANNEL - 1) {
-               ret = -ENOSPC;
-               goto end;
-       }
-       ret = setting->free_event_id++;
-end:
-       return ret;
-}
-
-/**
- * ltt_channels_get_event_id - get next event ID for a marker
- * @channel: channel name
- * @name: event name
- *
- * Returns a unique event ID (for this channel) or < 0 on error.
- */
-int ltt_channels_get_event_id(const char *channel, const char *name)
-{
-       int ret;
-
-       mutex_lock(&ltt_channel_mutex);
-       ret = _ltt_channels_get_event_id(channel, name);
-       mutex_unlock(&ltt_channel_mutex);
-       return ret;
-}
-
-/**
- * ltt_channels_reset_event_ids - reset event IDs at compaction
- *
- * Called with lock marker and channel mutex held.
- */
-void _ltt_channels_reset_event_ids(void)
-{
-       struct ltt_channel_setting *iter;
-
-       list_for_each_entry(iter, &ltt_channels, list)
-               iter->free_event_id = 0;
-}
-
-MODULE_LICENSE("GPL and additional rights");
-MODULE_AUTHOR("Mathieu Desnoyers");
-MODULE_DESCRIPTION("Linux Trace Toolkit Next Generation Channel Management");