[ltt-dev] [PATCH v5 1/5] Separate ltt_trace_create() into ltt_trace_create() and ltt_trace_alloc()
Mathieu Desnoyers
compudj at krystal.dyndns.org
Sun Nov 23 15:28:47 EST 2008
* Zhaolei (zhaolei at cn.fujitsu.com) wrote:
> This is step1 of:
> "switch marker list and marker activation (currently in /proc/ltt) to debugfs"
>
> > >> Are you means we can control each channel's (interrupt, process, ...)
> > >> subbuf in future version?
> > >> (I think current version can only control low, med and high)
> > >> If this is true, maybe we need modify ltt_trace_create() before impl
> > >> ltt_control.
> > >>
> > > Yes, this is the goal.
> > So, IMHO, we can do it in following steps:
> >
> > Step1: modify ltt_trace_create(), .etc, separate ltt_trace_create() into
> > ltt_trace_setup(), ltt_set_channelsize(), ltt_set_channelnum(),
> > ltt_trace_alloc(). But still use old netlink_based ltt_control to make
> > it simple.
> > Although we modify ltt_set_channelsize() to support setting each channel's
> > buffer, we make ltt_control.ko using old UI(only able to set low, med and
> > high). So we don't need to modify other program such as user-mode lttctl.
> >
>
> Yes. Just make sure a "destroy" deals correctly with a trace that is
> "setup" but not "allocated" yet.
>
> > Step2: Write a new module named ltt-channel-control.
> > ( I think name of ltt-channel-control will be better than ltt-control,
> > because we already have a module named ltt-marker-control. )
> > ltt-channel-control is designed on debugfs, as we discussed.
> > We can test it by echo XX > /mnt/debugfs/ltt/...
> >
>
> Yes, that would be perfect.
>
> > Step3: modify user-mode programs to support ltt-channel-control.
> > We also need to modify lttctl's command arguments, to support setup each
> > channel's buffer. (Are we take out -Z, -X, -V, -B, -z, -x in lttctl?)
> > I haven't read source of lttv, it is necessary to modify?
> >
>
> Maybe we could replace lttctl by simple shell scripts ?
>
> Yes, small modification of lttv would be required. There is a GUI module
> which executes lttctl to start/stop tracing. It would have to be
> modified so it uses the debugfs files instead.
>
> Signed-off-by: Zhao Lei <zhaolei at cn.fujitsu.com>
Excellent work ! will merge.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers at polymtl.ca>
> ---
> include/linux/ltt-core.h | 3 +-
> include/linux/ltt-tracer.h | 52 +++--
> ltt/ltt-core.c | 1 +
> ltt/ltt-tracer.c | 590 ++++++++++++++++++++++++++++++++------------
> 4 files changed, 475 insertions(+), 171 deletions(-)
>
> diff --git a/include/linux/ltt-core.h b/include/linux/ltt-core.h
> index 1681e82..7e5ee8b 100644
> --- a/include/linux/ltt-core.h
> +++ b/include/linux/ltt-core.h
> @@ -17,7 +17,8 @@
> * list.
> */
> struct ltt_traces {
> - struct list_head head; /* Traces list */
> + struct list_head setup_head; /* Pre-allocated traces list */
> + struct list_head head; /* Allocated Traces list */
> unsigned int num_active_traces; /* Number of active traces */
> } ____cacheline_aligned;
>
> diff --git a/include/linux/ltt-tracer.h b/include/linux/ltt-tracer.h
> index 277d42f..c4ac07c 100644
> --- a/include/linux/ltt-tracer.h
> +++ b/include/linux/ltt-tracer.h
> @@ -197,6 +197,23 @@ struct ltt_transport {
> struct ltt_trace_ops ops;
> };
>
> +/*
> + * First and last channels in ltt_trace_struct.
> + */
> +#define ltt_channel_index_size() sizeof(struct ltt_channel_struct *)
> +#define ltt_channel_index_begin() GET_CHANNEL_INDEX(cpu)
> +#define ltt_channel_index_end() \
> + (GET_CHANNEL_INDEX(metadata) + ltt_channel_index_size())
> +
> +enum ltt_channels {
> + LTT_CHANNEL_CPU,
> + LTT_CHANNEL_PROCESSES,
> + LTT_CHANNEL_INTERRUPTS,
> + LTT_CHANNEL_NETWORK,
> + LTT_CHANNEL_MODULES,
> + LTT_CHANNEL_METADATA,
> + NR_LTT_CHANNELS,
> +};
>
> enum trace_mode { LTT_TRACE_NORMAL, LTT_TRACE_FLIGHT, LTT_TRACE_HYBRID };
>
> @@ -218,6 +235,12 @@ struct ltt_trace_struct {
> struct ltt_channel_struct *modules;
> struct ltt_channel_struct *metadata;
> } channel;
> + struct {
> + struct {
> + unsigned subbuf_size;
> + unsigned subbuf_cnt;
> + } channels[NR_LTT_CHANNELS];
> + } setting;
> u32 freq_scale;
> u64 start_freq;
> u64 start_tsc;
> @@ -236,23 +259,6 @@ struct ltt_trace_struct {
> char trace_name[NAME_MAX];
> } ____cacheline_aligned;
>
> -/*
> - * First and last channels in ltt_trace_struct.
> - */
> -#define ltt_channel_index_size() sizeof(struct ltt_channel_struct *)
> -#define ltt_channel_index_begin() GET_CHANNEL_INDEX(cpu)
> -#define ltt_channel_index_end() \
> - (GET_CHANNEL_INDEX(metadata) + ltt_channel_index_size())
> -
> -enum ltt_channels {
> - LTT_CHANNEL_CPU,
> - LTT_CHANNEL_PROCESSES,
> - LTT_CHANNEL_INTERRUPTS,
> - LTT_CHANNEL_NETWORK,
> - LTT_CHANNEL_MODULES,
> - LTT_CHANNEL_METADATA,
> -};
> -
> /* Hardcoded event headers
> *
> * event header for a trace with active heartbeat : 27 bits timestamps
> @@ -690,6 +696,18 @@ union ltt_control_args {
> } new_trace;
> };
>
> +int ltt_trace_setup(const char *trace_name);
> +int ltt_trace_set_type(const char *trace_name, const char *trace_type);
> +int ltt_trace_set_mode(const char *trace_name, enum trace_mode mode);
> +int ltt_trace_set_channel_subbufsize(const char *trace_name,
> + const char *channel_name, unsigned size);
> +int ltt_trace_set_channel_subbufcount(const char *trace_name,
> + const char *channel_name, unsigned cnt);
> +int ltt_trace_alloc(const char *trace_name);
> +int ltt_trace_destroy(const char *trace_name);
> +int ltt_trace_start(const char *trace_name);
> +int ltt_trace_stop(const char *trace_name);
> +
> extern int ltt_control(enum ltt_control_msg msg, const char *trace_name,
> const char *trace_type, union ltt_control_args args);
>
> diff --git a/ltt/ltt-core.c b/ltt/ltt-core.c
> index abd3d6d..aaad358 100644
> --- a/ltt/ltt-core.c
> +++ b/ltt/ltt-core.c
> @@ -12,6 +12,7 @@
>
> /* Traces structures */
> struct ltt_traces ltt_traces = {
> + .setup_head = LIST_HEAD_INIT(ltt_traces.setup_head),
> .head = LIST_HEAD_INIT(ltt_traces.head),
> };
> EXPORT_SYMBOL(ltt_traces);
> diff --git a/ltt/ltt-tracer.c b/ltt/ltt-tracer.c
> index e86eb6d..b419329 100644
> --- a/ltt/ltt-tracer.c
> +++ b/ltt/ltt-tracer.c
> @@ -268,31 +268,20 @@ static struct ltt_trace_struct *_ltt_trace_find(const char *trace_name)
> return NULL;
> }
>
> -/* This function must be called with traces semaphore held. */
> -static int _ltt_trace_create(const char *trace_name, enum trace_mode mode,
> - struct ltt_trace_struct *new_trace)
> +/* _ltt_trace_find_setup :
> + * find a trace in setup list by given name.
> + *
> + * Returns a pointer to the trace structure, NULL if not found.
> + */
> +static struct ltt_trace_struct *_ltt_trace_find_setup(const char *trace_name)
> {
> - int err = EPERM;
> + struct ltt_trace_struct *trace;
>
> - if (_ltt_trace_find(trace_name) != NULL) {
> - printk(KERN_ERR "LTT : Trace %s already exists\n", trace_name);
> - err = EEXIST;
> - goto traces_error;
> - }
> - if (list_empty(<t_traces.head)) {
> - probe_id_defrag();
> - mod_timer(<t_async_wakeup_timer,
> - jiffies + LTT_PERCPU_TIMER_INTERVAL);
> - set_kernel_trace_flag_all_tasks();
> - }
> - list_add_rcu(&new_trace->list, <t_traces.head);
> - synchronize_sched();
> - /* Everything went fine, finish creation */
> - return 0;
> + list_for_each_entry(trace, <t_traces.setup_head, list)
> + if (!strncmp(trace->trace_name, trace_name, NAME_MAX))
> + return trace;
>
> - /* Error handling */
> -traces_error:
> - return err;
> + return NULL;
> }
>
> /**
> @@ -334,172 +323,443 @@ static inline void prepare_chan_size_num(unsigned *subbuf_size,
> WARN_ON(hweight32(*n_subbufs) != 1);
> }
>
> -static int ltt_trace_create(const char *trace_name, const char *trace_type,
> - enum trace_mode mode,
> - unsigned subbuf_size_low, unsigned n_subbufs_low,
> - unsigned subbuf_size_med, unsigned n_subbufs_med,
> - unsigned subbuf_size_high, unsigned n_subbufs_high)
> +int ltt_trace_setup(const char *trace_name)
> {
> int err = 0;
> - struct ltt_trace_struct *new_trace, *trace;
> - unsigned long flags;
> - struct ltt_transport *tran, *transport = NULL;
> + struct ltt_trace_struct *new_trace = NULL;
>
> - prepare_chan_size_num(&subbuf_size_low, &n_subbufs_low,
> - LTT_DEFAULT_SUBBUF_SIZE_LOW, LTT_DEFAULT_N_SUBBUFS_LOW);
> + ltt_lock_traces();
>
> - prepare_chan_size_num(&subbuf_size_med, &n_subbufs_med,
> - LTT_DEFAULT_SUBBUF_SIZE_MED, LTT_DEFAULT_N_SUBBUFS_MED);
> + if (_ltt_trace_find_setup(trace_name)) {
> + printk(KERN_ERR "LTT : Trace name %s already used.\n",
> + trace_name);
> + err = -EEXIST;
> + goto traces_error;
> + }
>
> - prepare_chan_size_num(&subbuf_size_high, &n_subbufs_high,
> - LTT_DEFAULT_SUBBUF_SIZE_HIGH, LTT_DEFAULT_N_SUBBUFS_HIGH);
> + if (_ltt_trace_find(trace_name)) {
> + printk(KERN_ERR "LTT : Trace name %s already used.\n",
> + trace_name);
> + err = -EEXIST;
> + goto traces_error;
> + }
>
> new_trace = kzalloc(sizeof(struct ltt_trace_struct), GFP_KERNEL);
> if (!new_trace) {
> printk(KERN_ERR
> "LTT : Unable to allocate memory for trace %s\n",
> trace_name);
> - err = ENOMEM;
> - goto traces_error;
> + err = -ENOMEM;
> + goto trace_free;
> }
>
> - kref_init(&new_trace->kref);
> - kref_init(&new_trace->ltt_transport_kref);
> - init_waitqueue_head(&new_trace->kref_wq);
> - new_trace->active = 0;
> strncpy(new_trace->trace_name, trace_name, NAME_MAX);
> - new_trace->mode = mode;
> - get_trace_clock();
> - new_trace->freq_scale = trace_clock_freq_scale();
> + list_add(&new_trace->list, <t_traces.setup_head);
> +
> + ltt_unlock_traces();
> +
> + return 0;
> +
> +trace_free:
> + kfree(new_trace);
> +traces_error:
> + ltt_unlock_traces();
> + return err;
> +}
> +EXPORT_SYMBOL_GPL(ltt_trace_setup);
> +
> +/* must be called from within a traces lock. */
> +static void _ltt_trace_free(struct ltt_trace_struct *trace)
> +{
> + list_del(&trace->list);
> + kfree(trace);
> +}
> +
> +int ltt_trace_set_type(const char *trace_name, const char *trace_type)
> +{
> + int err = 0;
> + struct ltt_trace_struct *trace;
> + struct ltt_transport *tran_iter, *transport = NULL;
>
> ltt_lock_traces();
> - list_for_each_entry(tran, <t_transport_list, node) {
> - if (!strcmp(tran->name, trace_type)) {
> - transport = tran;
> +
> + trace = _ltt_trace_find_setup(trace_name);
> + if (!trace) {
> + printk(KERN_ERR "LTT : Trace not found %s\n", trace_name);
> + err = -ENOENT;
> + goto traces_error;
> + }
> +
> + list_for_each_entry(tran_iter, <t_transport_list, node) {
> + if (!strcmp(tran_iter->name, trace_type)) {
> + transport = tran_iter;
> break;
> }
> }
> -
> if (!transport) {
> - err = EINVAL;
> printk(KERN_ERR "LTT : Transport %s is not present.\n",
> trace_type);
> - ltt_unlock_traces();
> - goto trace_error;
> + err = -EINVAL;
> + goto traces_error;
> }
>
> - if (!try_module_get(transport->owner)) {
> - err = ENODEV;
> - printk(KERN_ERR "LTT : Can't lock transport module.\n");
> - ltt_unlock_traces();
> - goto trace_error;
> + trace->transport = transport;
> +
> +traces_error:
> + ltt_unlock_traces();
> + return err;
> +}
> +EXPORT_SYMBOL_GPL(ltt_trace_set_type);
> +
> +int ltt_trace_set_mode(const char *trace_name, enum trace_mode mode)
> +{
> + int err = 0;
> + struct ltt_trace_struct *trace;
> +
> + ltt_lock_traces();
> +
> + trace = _ltt_trace_find_setup(trace_name);
> + if (!trace) {
> + printk(KERN_ERR "LTT : Trace not found %s\n", trace_name);
> + err = -ENOENT;
> + goto traces_error;
> }
>
> - trace = _ltt_trace_find(trace_name);
> - if (trace) {
> - printk(KERN_ERR "LTT : Trace name %s already used.\n",
> - trace_name);
> - err = EEXIST;
> - goto trace_error;
> + trace->mode = mode;
> +
> +traces_error:
> + ltt_unlock_traces();
> + return err;
> +}
> +EXPORT_SYMBOL_GPL(ltt_trace_set_mode);
> +
> +/*
> + * Todo:
> + * Make similar function in channel.c,
> + * so it will be useful for both ltt-tracer.c and ltt-marker-control.c
> + */
> +/*
> + * Its order is MUST be same with enum ltt_channels
> + */
> +struct chan_info_struct {
> + const char *name;
> + unsigned int channel_index;
> + unsigned int def_subbufsize;
> + unsigned int def_subbufcount;
> +} chan_infos[] = {
> + [LTT_CHANNEL_CPU] = {
> + LTT_CPU_CHANNEL,
> + GET_CHANNEL_INDEX(cpu),
> + LTT_DEFAULT_SUBBUF_SIZE_HIGH,
> + LTT_DEFAULT_N_SUBBUFS_HIGH,
> + },
> + [LTT_CHANNEL_PROCESSES] = {
> + LTT_PROCESSES_CHANNEL,
> + GET_CHANNEL_INDEX(processes),
> + LTT_DEFAULT_SUBBUF_SIZE_MED,
> + LTT_DEFAULT_N_SUBBUFS_MED,
> + },
> + [LTT_CHANNEL_INTERRUPTS] = {
> + LTT_INTERRUPTS_CHANNEL,
> + GET_CHANNEL_INDEX(interrupts),
> + LTT_DEFAULT_SUBBUF_SIZE_LOW,
> + LTT_DEFAULT_N_SUBBUFS_LOW,
> + },
> + [LTT_CHANNEL_NETWORK] = {
> + LTT_NETWORK_CHANNEL,
> + GET_CHANNEL_INDEX(network),
> + LTT_DEFAULT_SUBBUF_SIZE_LOW,
> + LTT_DEFAULT_N_SUBBUFS_LOW,
> + },
> + [LTT_CHANNEL_MODULES] = {
> + LTT_MODULES_CHANNEL,
> + GET_CHANNEL_INDEX(modules),
> + LTT_DEFAULT_SUBBUF_SIZE_LOW,
> + LTT_DEFAULT_N_SUBBUFS_LOW,
> + },
> + [LTT_CHANNEL_METADATA] = {
> + LTT_METADATA_CHANNEL,
> + GET_CHANNEL_INDEX(metadata),
> + LTT_DEFAULT_SUBBUF_SIZE_LOW,
> + LTT_DEFAULT_N_SUBBUFS_LOW,
> + },
> +};
> +
> +static enum ltt_channels get_channel_type_from_name(const char *name)
> +{
> + int i;
> +
> + for (i = 0; i < ARRAY_SIZE(chan_infos); i++)
> + if (!strcmp(name, chan_infos[i].name))
> + return (enum ltt_channels)i;
> +
> + return NR_LTT_CHANNELS;
> +}
> +
> +int ltt_trace_set_channel_subbufsize(const char *trace_name,
> + const char *channel_name, unsigned size)
> +{
> + int err = 0;
> + struct ltt_trace_struct *trace;
> + enum ltt_channels channel;
> +
> + ltt_lock_traces();
> +
> + trace = _ltt_trace_find_setup(trace_name);
> + if (!trace) {
> + printk(KERN_ERR "LTT : Trace not found %s\n", trace_name);
> + err = -ENOENT;
> + goto traces_error;
> }
>
> - new_trace->transport = transport;
> - new_trace->ops = &transport->ops;
> + channel = get_channel_type_from_name(channel_name);
> + if (channel == NR_LTT_CHANNELS) {
> + printk(KERN_ERR "LTT : Channel %s is not present.\n",
> + channel_name);
> + err = -EINVAL;
> + goto traces_error;
> + }
>
> - err = new_trace->ops->create_dirs(new_trace);
> - if (err)
> + trace->setting.channels[channel].subbuf_size = size;
> +
> +traces_error:
> + ltt_unlock_traces();
> + return err;
> +}
> +EXPORT_SYMBOL_GPL(ltt_trace_set_channel_subbufsize);
> +
> +int ltt_trace_set_channel_subbufcount(const char *trace_name,
> + const char *channel_name, unsigned cnt)
> +{
> + int err = 0;
> + struct ltt_trace_struct *trace;
> + enum ltt_channels channel;
> +
> + ltt_lock_traces();
> +
> + trace = _ltt_trace_find_setup(trace_name);
> + if (!trace) {
> + printk(KERN_ERR "LTT : Trace not found %s\n", trace_name);
> + err = -ENOENT;
> + goto traces_error;
> + }
> +
> + channel = get_channel_type_from_name(channel_name);
> + if (channel == NR_LTT_CHANNELS) {
> + printk(KERN_ERR "LTT : Channel %s is not present.\n",
> + channel_name);
> + err = -EINVAL;
> + goto traces_error;
> + }
> +
> + trace->setting.channels[channel].subbuf_cnt = cnt;
> +
> +traces_error:
> + ltt_unlock_traces();
> + return err;
> +}
> +EXPORT_SYMBOL_GPL(ltt_trace_set_channel_subbufcount);
> +
> +int ltt_trace_alloc(const char *trace_name)
> +{
> + int err = 0;
> + struct ltt_trace_struct *trace;
> + int subbuf_size, subbuf_cnt;
> + unsigned long flags;
> + int chan;
> +
> + ltt_lock_traces();
> +
> + trace = _ltt_trace_find_setup(trace_name);
> + if (!trace) {
> + printk(KERN_ERR "LTT : Trace not found %s\n", trace_name);
> + err = -ENOENT;
> + goto traces_error;
> + }
> +
> + kref_init(&trace->kref);
> + kref_init(&trace->ltt_transport_kref);
> + init_waitqueue_head(&trace->kref_wq);
> + trace->active = 0;
> + get_trace_clock();
> + trace->freq_scale = trace_clock_freq_scale();
> +
> + if (!trace->transport) {
> + printk(KERN_ERR "LTT : Transport is not set.\n");
> + err = -EINVAL;
> + goto transport_error;
> + }
> + if (!try_module_get(trace->transport->owner)) {
> + printk(KERN_ERR "LTT : Can't lock transport module.\n");
> + err = -ENODEV;
> + goto transport_error;
> + }
> + trace->ops = &trace->transport->ops;
> +
> + err = trace->ops->create_dirs(trace);
> + if (err) {
> + printk(KERN_ERR "LTT : Can't create dir for trace %s.\n",
> + trace_name);
> goto dirs_error;
> + }
>
> local_irq_save(flags);
> - new_trace->start_freq = trace_clock_frequency();
> - new_trace->start_tsc = trace_clock_read64();
> - do_gettimeofday(&new_trace->start_time);
> + trace->start_freq = trace_clock_frequency();
> + trace->start_tsc = trace_clock_read64();
> + do_gettimeofday(&trace->start_time);
> local_irq_restore(flags);
>
> /*
> + * Todo:
> + * Config each channel's default buffersize/cnt, instead of
> + * LTT_DEFAULT_SUBBUF_SIZE_LOW, ...
> + */
> +
> + /*
> * Always put the metadata channel in non-overwrite mode :
> * This is a very low traffic channel and it can't afford to have its
> * data overwritten : this data (marker info) is necessary to be
> * able to read the trace.
> */
> - err = new_trace->ops->create_channel(trace_name, new_trace,
> - new_trace->dentry.control_root,
> - LTT_METADATA_CHANNEL,
> - &new_trace->channel.metadata, subbuf_size_low,
> - n_subbufs_low,
> - is_channel_overwrite(LTT_CHANNEL_METADATA, mode));
> - if (err != 0)
> - goto metadata_error;
> - err = new_trace->ops->create_channel(trace_name, new_trace,
> - new_trace->dentry.control_root,
> - LTT_INTERRUPTS_CHANNEL,
> - &new_trace->channel.interrupts, subbuf_size_low,
> - n_subbufs_low,
> - is_channel_overwrite(LTT_CHANNEL_INTERRUPTS, mode));
> - if (err != 0)
> - goto interrupts_error;
> - err = new_trace->ops->create_channel(trace_name, new_trace,
> - new_trace->dentry.control_root,
> - LTT_PROCESSES_CHANNEL,
> - &new_trace->channel.processes, subbuf_size_med,
> - n_subbufs_med,
> - is_channel_overwrite(LTT_CHANNEL_PROCESSES, mode));
> - if (err != 0)
> - goto processes_error;
> - err = new_trace->ops->create_channel(trace_name, new_trace,
> - new_trace->dentry.control_root,
> - LTT_MODULES_CHANNEL,
> - &new_trace->channel.modules, subbuf_size_low,
> - n_subbufs_low,
> - is_channel_overwrite(LTT_CHANNEL_MODULES, mode));
> - if (err != 0)
> - goto modules_error;
> - err = new_trace->ops->create_channel(trace_name, new_trace,
> - new_trace->dentry.control_root,
> - LTT_NETWORK_CHANNEL,
> - &new_trace->channel.network, subbuf_size_low,
> - n_subbufs_low,
> - is_channel_overwrite(LTT_CHANNEL_NETWORK, mode));
> - if (err != 0)
> - goto network_error;
> - err = new_trace->ops->create_channel(trace_name, new_trace,
> - new_trace->dentry.trace_root,
> - LTT_CPU_CHANNEL,
> - &new_trace->channel.cpu, subbuf_size_high,
> - n_subbufs_high,
> - is_channel_overwrite(LTT_CHANNEL_CPU, mode));
> - if (err != 0)
> - goto cpu_error;
> -
> - err = _ltt_trace_create(trace_name, mode, new_trace);
> -
> - if (err != 0)
> - goto lock_create_error;
> + for (chan = 0; chan < NR_LTT_CHANNELS; chan++) {
> + subbuf_size = trace->setting.channels[chan].subbuf_size;
> + subbuf_cnt = trace->setting.channels[chan].subbuf_cnt;
> + prepare_chan_size_num(&subbuf_size, &subbuf_cnt,
> + chan_infos[chan].def_subbufsize,
> + chan_infos[chan].def_subbufcount);
> + err = trace->ops->create_channel(trace_name, trace,
> + trace->dentry.control_root,
> + chan_infos[chan].name,
> + (struct ltt_channel_struct **)((char *)trace
> + + chan_infos[chan].channel_index),
> + subbuf_size,
> + subbuf_cnt,
> + is_channel_overwrite(chan, trace->mode));
> + if (err != 0) {
> + printk(KERN_ERR "LTT : Can't create channel %s.\n",
> + chan_infos[chan].name);
> + goto create_channel_error;
> + }
> + }
> +
> + list_del(&trace->list);
> + if (list_empty(<t_traces.head)) {
> + probe_id_defrag();
> + mod_timer(<t_async_wakeup_timer,
> + jiffies + LTT_PERCPU_TIMER_INTERVAL);
> + set_kernel_trace_flag_all_tasks();
> + }
> + list_add_rcu(&trace->list, <t_traces.head);
> + synchronize_sched();
> +
> ltt_unlock_traces();
> - return err;
>
> -lock_create_error:
> - new_trace->ops->remove_channel(new_trace->channel.cpu);
> -cpu_error:
> - new_trace->ops->remove_channel(new_trace->channel.network);
> -network_error:
> - new_trace->ops->remove_channel(new_trace->channel.modules);
> -modules_error:
> - new_trace->ops->remove_channel(new_trace->channel.processes);
> -processes_error:
> - new_trace->ops->remove_channel(new_trace->channel.interrupts);
> -interrupts_error:
> - new_trace->ops->remove_channel(new_trace->channel.metadata);
> -metadata_error:
> - kref_put(&new_trace->ltt_transport_kref, ltt_release_transport);
> + return 0;
> +
> +create_channel_error:
> + for (chan--; chan >= 0; chan--)
> + trace->ops->remove_channel(*(struct ltt_channel_struct **)
> + ((char *)trace + chan_infos[chan].channel_index));
> +
> dirs_error:
> - module_put(transport->owner);
> -trace_error:
> - kref_put(&new_trace->kref, ltt_release_trace);
> - wake_up_interruptible(&new_trace->kref_wq);
> - ltt_unlock_traces();
> + module_put(trace->transport->owner);
> +transport_error:
> put_trace_clock();
> traces_error:
> + ltt_unlock_traces();
> + return err;
> +}
> +EXPORT_SYMBOL_GPL(ltt_trace_alloc);
> +
> +/*
> + * It is worked as a wrapper for current version of ltt_control.ko.
> + * We will make a new ltt_control based on debugfs, and control each channel's
> + * buffer.
> + */
> +static int ltt_trace_create(const char *trace_name, const char *trace_type,
> + enum trace_mode mode,
> + unsigned subbuf_size_low, unsigned n_subbufs_low,
> + unsigned subbuf_size_med, unsigned n_subbufs_med,
> + unsigned subbuf_size_high, unsigned n_subbufs_high)
> +{
> + int err = 0;
> +
> + err = ltt_trace_setup(trace_name);
> + if (IS_ERR_VALUE(err))
> + return err;
> +
> + err = ltt_trace_set_type(trace_name, trace_type);
> + if (IS_ERR_VALUE(err))
> + return err;
> +
> + err = ltt_trace_set_mode(trace_name, mode);
> + if (IS_ERR_VALUE(err))
> + return err;
> +
> + err = ltt_trace_set_channel_subbufsize(trace_name,
> + LTT_METADATA_CHANNEL, subbuf_size_low);
> + if (IS_ERR_VALUE(err))
> + return err;
> +
> + err = ltt_trace_set_channel_subbufcount(trace_name,
> + LTT_METADATA_CHANNEL, n_subbufs_low);
> + if (IS_ERR_VALUE(err))
> + return err;
> +
> + err = ltt_trace_set_channel_subbufsize(trace_name,
> + LTT_INTERRUPTS_CHANNEL, subbuf_size_low);
> + if (IS_ERR_VALUE(err))
> + return err;
> +
> + err = ltt_trace_set_channel_subbufcount(trace_name,
> + LTT_INTERRUPTS_CHANNEL, n_subbufs_low);
> + if (IS_ERR_VALUE(err))
> + return err;
> +
> + err = ltt_trace_set_channel_subbufsize(trace_name,
> + LTT_PROCESSES_CHANNEL, subbuf_size_med);
> + if (IS_ERR_VALUE(err))
> + return err;
> +
> + err = ltt_trace_set_channel_subbufcount(trace_name,
> + LTT_PROCESSES_CHANNEL, n_subbufs_med);
> + if (IS_ERR_VALUE(err))
> + return err;
> +
> + err = ltt_trace_set_channel_subbufsize(trace_name, LTT_MODULES_CHANNEL,
> + subbuf_size_low);
> + if (IS_ERR_VALUE(err))
> + return err;
> +
> + err = ltt_trace_set_channel_subbufcount(trace_name, LTT_MODULES_CHANNEL,
> + n_subbufs_low);
> + if (IS_ERR_VALUE(err))
> + return err;
> +
> + err = ltt_trace_set_channel_subbufsize(trace_name, LTT_NETWORK_CHANNEL,
> + subbuf_size_low);
> + if (IS_ERR_VALUE(err))
> + return err;
> +
> + err = ltt_trace_set_channel_subbufcount(trace_name, LTT_NETWORK_CHANNEL,
> + n_subbufs_low);
> + if (IS_ERR_VALUE(err))
> + return err;
> +
> + err = ltt_trace_set_channel_subbufsize(trace_name, LTT_CPU_CHANNEL,
> + subbuf_size_high);
> + if (IS_ERR_VALUE(err))
> + return err;
> +
> + err = ltt_trace_set_channel_subbufcount(trace_name, LTT_CPU_CHANNEL,
> + n_subbufs_high);
> + if (IS_ERR_VALUE(err))
> + return err;
> +
> + err = ltt_trace_alloc(trace_name);
> + if (IS_ERR_VALUE(err))
> + return err;
> +
> return err;
> }
>
> @@ -581,26 +841,42 @@ static void __ltt_trace_destroy(struct ltt_trace_struct *trace)
> kref_put(&trace->kref, ltt_release_trace);
> }
>
> -static int ltt_trace_destroy(const char *trace_name)
> +int ltt_trace_destroy(const char *trace_name)
> {
> int err = 0;
> struct ltt_trace_struct *trace;
>
> ltt_lock_traces();
> +
> trace = _ltt_trace_find(trace_name);
> - err = _ltt_trace_destroy(trace);
> - if (err)
> - goto error;
> - ltt_unlock_traces();
> - __ltt_trace_destroy(trace);
> - put_trace_clock();
> - return err;
> + if (trace) {
> + err = _ltt_trace_destroy(trace);
> + if (err)
> + goto error;
> +
> + ltt_unlock_traces();
> +
> + __ltt_trace_destroy(trace);
> + put_trace_clock();
> +
> + return 0;
> + }
> +
> + trace = _ltt_trace_find_setup(trace_name);
> + if (trace) {
> + _ltt_trace_free(trace);
> + ltt_unlock_traces();
> + return 0;
> + }
> +
> + err = ENOENT;
>
> /* Error handling */
> error:
> ltt_unlock_traces();
> return err;
> }
> +EXPORT_SYMBOL_GPL(ltt_trace_destroy);
>
> /* must be called from within a traces lock. */
> static int _ltt_trace_start(struct ltt_trace_struct *trace)
> @@ -630,7 +906,7 @@ traces_error:
> return err;
> }
>
> -static int ltt_trace_start(const char *trace_name)
> +int ltt_trace_start(const char *trace_name)
> {
> int err = 0;
> struct ltt_trace_struct *trace;
> @@ -670,6 +946,7 @@ no_trace:
> ltt_unlock_traces();
> return err;
> }
> +EXPORT_SYMBOL_GPL(ltt_trace_start);
>
> /* must be called from within traces lock */
> static int _ltt_trace_stop(struct ltt_trace_struct *trace)
> @@ -697,7 +974,7 @@ traces_error:
> return err;
> }
>
> -static int ltt_trace_stop(const char *trace_name)
> +int ltt_trace_stop(const char *trace_name)
> {
> int err = 0;
> struct ltt_trace_struct *trace;
> @@ -708,6 +985,7 @@ static int ltt_trace_stop(const char *trace_name)
> ltt_unlock_traces();
> return err;
> }
> +EXPORT_SYMBOL_GPL(ltt_trace_stop);
>
> /**
> * ltt_control : Trace control in-kernel API
> @@ -820,6 +1098,12 @@ static void __exit ltt_exit(void)
> _ltt_trace_destroy(trace);
> __ltt_trace_destroy(trace);
> }
> + /* free traces in pre-alloc status */
> + list_for_each_safe(pos, n, <t_traces.setup_head) {
> + trace = container_of(pos, struct ltt_trace_struct, list);
> + _ltt_trace_free(trace);
> + }
> +
> ltt_unlock_traces();
> }
>
> --
> 1.5.5.3
>
>
>
> _______________________________________________
> ltt-dev mailing list
> ltt-dev at lists.casi.polymtl.ca
> http://lists.casi.polymtl.ca/cgi-bin/mailman/listinfo/ltt-dev
>
--
Mathieu Desnoyers
OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F BA06 3F25 A8FE 3BAE 9A68
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