Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756636AbZCXHTy (ORCPT ); Tue, 24 Mar 2009 03:19:54 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751133AbZCXHTo (ORCPT ); Tue, 24 Mar 2009 03:19:44 -0400 Received: from an-out-0708.google.com ([209.85.132.246]:47575 "EHLO an-out-0708.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750978AbZCXHTo (ORCPT ); Tue, 24 Mar 2009 03:19:44 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=subject:from:to:cc:in-reply-to:references:content-type:date :message-id:mime-version:x-mailer:content-transfer-encoding; b=eKf6K7+O0PvcMH39ciLztjnSqKzsgj/LC/9JSlpNhnEn8JEcvIFxPgjRuGKa/iEvBy 51Dvo4NawcokQexD5cI7cCc5OEaP+yQhT9B1fSEcArcF2R7nWJxc3rXKJB+7tnJQLdZ2 /ImSSTaUusueNhXZx7somS+8OfQpcIZs4g+1Q= Subject: Re: [PATCH 4/4] tracing: add per-subsystem filtering From: Tom Zanussi To: Steven Rostedt Cc: linux-kernel , Ingo Molnar , =?ISO-8859-1?Q?Fr=E9d=E9ric?= Weisbecker In-Reply-To: References: <1237710677.7703.49.camel@charm-linux> Content-Type: text/plain Date: Tue, 24 Mar 2009 02:19:39 -0500 Message-Id: <1237879179.8339.67.camel@charm-linux> Mime-Version: 1.0 X-Mailer: Evolution 2.12.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 6783 Lines: 235 Hi, On Mon, 2009-03-23 at 14:24 -0400, Steven Rostedt wrote: > On Sun, 22 Mar 2009, Tom Zanussi wrote: > > > > +struct event_subsystem { > > + struct list_head list; > > + const char *name; > > + struct dentry *entry; > > + struct filter_pred **preds; > > +}; > > + > > +#define events_for_each(event) \ > > + for (event = __start_ftrace_events; \ > > + (unsigned long)event < (unsigned long)__stop_ftrace_events; \ > > + event++) > > + > > #define MAX_FILTER_PRED 8 > > > > struct filter_pred; > > @@ -832,6 +844,9 @@ extern int filter_add_pred(struct ftrace_event_call *call, > > struct filter_pred *pred); > > extern void filter_free_preds(struct ftrace_event_call *call); > > extern int filter_match_preds(struct ftrace_event_call *call, void *rec); > > +extern void filter_free_subsystem_preds(struct event_subsystem *system); > > +extern int filter_add_subsystem_pred(struct event_subsystem *system, > > + struct filter_pred *pred); > > > > void event_trace_printk(unsigned long ip, const char *fmt, ...); > > extern struct ftrace_event_call __start_ftrace_events[]; > > diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c > > index 97470c4..97d4daa 100644 > > --- a/kernel/trace/trace_events.c > > +++ b/kernel/trace/trace_events.c > > @@ -524,6 +524,71 @@ event_filter_write(struct file *filp, const char __user *ubuf, size_t cnt, > > return cnt; > > } > > > > +static ssize_t > > +subsystem_filter_read(struct file *filp, char __user *ubuf, size_t cnt, > > + loff_t *ppos) > > +{ > > + struct event_subsystem *system = filp->private_data; > > + struct trace_seq *s; > > Again, trace_seq is not used, might as well use your own buffer. > > > + int r; > > + > > + if (*ppos) > > + return 0; > > + > > + s = kmalloc(sizeof(*s), GFP_KERNEL); > > + if (!s) > > + return -ENOMEM; > > + > > + trace_seq_init(s); > > + > > + r = filter_print_preds(system->preds, s->buffer); > > + r = simple_read_from_buffer(ubuf, cnt, ppos, s->buffer, r); > > + > > + kfree(s); > > + > > + return r; > > +} > > + > > +static ssize_t > > +subsystem_filter_write(struct file *filp, const char __user *ubuf, size_t cnt, > > + loff_t *ppos) > > +{ > > + struct event_subsystem *system = filp->private_data; > > + char buf[64], *pbuf = buf; > > + struct filter_pred *pred; > > + int err; > > + > > + if (cnt >= sizeof(buf)) > > + return -EINVAL; > > + > > + if (copy_from_user(&buf, ubuf, cnt)) > > + return -EFAULT; > > + > > + pred = kzalloc(sizeof(*pred), GFP_KERNEL); > > + if (!pred) > > + return -ENOMEM; > > + > > + err = filter_parse(&pbuf, pred); > > + if (err < 0) { > > + filter_free_pred(pred); > > + return err; > > + } > > + > > + if (pred->clear) { > > + filter_free_subsystem_preds(system); > > is "system" correct here? Do you mean the naming i.e. would be better as "subsystem"? Otherwise, I think it's correct. > > > + return cnt; > > + } > > + > > + if (filter_add_subsystem_pred(system, pred)) { > > + filter_free_pred(pred); > > + return -EINVAL; > > + } > > + > > + *ppos += cnt; > > + > > + return cnt; > > +} > > + > > static const struct seq_operations show_event_seq_ops = { > > .start = t_start, > > .next = t_next, > > @@ -575,6 +640,12 @@ static const struct file_operations ftrace_event_filter_fops = { > > .write = event_filter_write, > > }; > > > > +static const struct file_operations ftrace_subsystem_filter_fops = { > > + .open = tracing_open_generic, > > + .read = subsystem_filter_read, > > + .write = subsystem_filter_write, > > +}; > > + > > static struct dentry *event_trace_events_dir(void) > > { > > static struct dentry *d_tracer; > > @@ -595,18 +666,13 @@ static struct dentry *event_trace_events_dir(void) > > return d_events; > > } > > > > -struct event_subsystem { > > - struct list_head list; > > - const char *name; > > - struct dentry *entry; > > -}; > > - > > static LIST_HEAD(event_subsystems); > > > > static struct dentry * > > event_subsystem_dir(const char *name, struct dentry *d_events) > > { > > struct event_subsystem *system; > > + struct dentry *entry; > > > > /* First see if we did not already create this dir */ > > list_for_each_entry(system, &event_subsystems, list) { > > @@ -633,6 +699,14 @@ event_subsystem_dir(const char *name, struct dentry *d_events) > > system->name = name; > > list_add(&system->list, &event_subsystems); > > > > + system->preds = NULL; > > + > > + entry = debugfs_create_file("filter", 0444, system->entry, system, > > + &ftrace_subsystem_filter_fops); > > + if (!entry) > > + pr_warning("Could not create debugfs " > > + "'%s/filter' entry\n", name); > > + > > return system->entry; > > } > > > > diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c > > index 8e8c5fa..1ab20ce 100644 > > --- a/kernel/trace/trace_events_filter.c > > +++ b/kernel/trace/trace_events_filter.c > > @@ -181,6 +181,27 @@ void filter_free_preds(struct ftrace_event_call *call) > > } > > } > > > > +void filter_free_subsystem_preds(struct event_subsystem *system) > > +{ > > + struct ftrace_event_call *call = __start_ftrace_events; > > + int i; > > + > > + if (system->preds) { > > + for (i = 0; i < MAX_FILTER_PRED; i++) > > + filter_free_pred(system->preds[i]); > > + kfree(system->preds); > > + system->preds = NULL; > > + } > > + > > + events_for_each(call) { > > + if (!call->name || !call->regfunc) > > + continue; > > + > > + if (!strcmp(call->system, system->name)) > > + filter_free_preds(call); > > + } > > +} > > + > > static int __filter_add_pred(struct ftrace_event_call *call, > > struct filter_pred *pred) > > { > > @@ -250,6 +271,65 @@ int filter_add_pred(struct ftrace_event_call *call, struct filter_pred *pred) > > return __filter_add_pred(call, pred); > > } > > > > +static struct filter_pred *copy_pred(struct filter_pred *pred) > > +{ > > + struct filter_pred *new_pred = kmalloc(sizeof(*pred), GFP_KERNEL); > > + if (!new_pred) > > + return NULL; > > + > > + memcpy(new_pred, pred, sizeof(*pred)); > > + if (pred->str_val) { > > + new_pred->str_val = kstrdup(pred->str_val, GFP_KERNEL); > > + new_pred->field_name = kstrdup(pred->field_name, GFP_KERNEL); > > + if (!new_pred->str_val) { > > + kfree(new_pred); > > Shouldn't there be a check for field_name too? > Yes - I posted a patch to copy_pred() yesterday to fix that. Tom > -- Steve > > > + return NULL; > > + } > > + } > > + > > + return new_pred; > > +} > > + -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/