+++ /dev/null
-/*
- * Copyright (C) 2007 Mathieu Desnoyers
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
- */
-//ust// #include <linux/module.h>
-//ust// #include <linux/mutex.h>
-//ust// #include <linux/types.h>
-#include "jhash.h"
-#include "list.h"
-#include "rcupdate.h"
-//ust// #include <linux/marker.h>
-#include <errno.h>
-//ust// #include <linux/slab.h>
-//ust// #include <linux/immediate.h>
-//ust// #include <linux/sched.h>
-//ust// #include <linux/uaccess.h>
-//ust// #include <linux/user_marker.h>
-//ust// #include <linux/ltt-tracer.h>
-
-#include "marker.h"
-#include "kernelcompat.h"
-#include "usterr.h"
-#include "channels.h"
-#include "tracercore.h"
-#include "tracer.h"
-
-extern struct marker __start___markers[] __attribute__((visibility("hidden")));
-extern struct marker __stop___markers[] __attribute__((visibility("hidden")));
-
-/* Set to 1 to enable marker debug output */
-static const int marker_debug;
-
-/*
- * markers_mutex nests inside module_mutex. Markers mutex protects the builtin
- * and module markers and the hash table.
- */
-static DEFINE_MUTEX(markers_mutex);
-
-void lock_markers(void)
-{
- mutex_lock(&markers_mutex);
-}
-
-void unlock_markers(void)
-{
- mutex_unlock(&markers_mutex);
-}
-
-/*
- * Marker hash table, containing the active markers.
- * Protected by module_mutex.
- */
-#define MARKER_HASH_BITS 6
-#define MARKER_TABLE_SIZE (1 << MARKER_HASH_BITS)
-static struct hlist_head marker_table[MARKER_TABLE_SIZE];
-
-/*
- * Note about RCU :
- * It is used to make sure every handler has finished using its private data
- * between two consecutive operation (add or remove) on a given marker. It is
- * also used to delay the free of multiple probes array until a quiescent state
- * is reached.
- * marker entries modifications are protected by the markers_mutex.
- */
-struct marker_entry {
- struct hlist_node hlist;
- char *format;
- char *name;
- /* Probe wrapper */
- void (*call)(const struct marker *mdata, void *call_private, ...);
- struct marker_probe_closure single;
- struct marker_probe_closure *multi;
- int refcount; /* Number of times armed. 0 if disarmed. */
- struct rcu_head rcu;
- void *oldptr;
- int rcu_pending;
- u16 channel_id;
- u16 event_id;
- unsigned char ptype:1;
- unsigned char format_allocated:1;
- char channel[0]; /* Contains channel'\0'name'\0'format'\0' */
-};
-
-#ifdef CONFIG_MARKERS_USERSPACE
-static void marker_update_processes(void);
-#else
-static void marker_update_processes(void)
-{
-}
-#endif
-
-/**
- * __mark_empty_function - Empty probe callback
- * @mdata: marker data
- * @probe_private: probe private data
- * @call_private: call site private data
- * @fmt: format string
- * @...: variable argument list
- *
- * Empty callback provided as a probe to the markers. By providing this to a
- * disabled marker, we make sure the execution flow is always valid even
- * though the function pointer change and the marker enabling are two distinct
- * operations that modifies the execution flow of preemptible code.
- */
-notrace void __mark_empty_function(const struct marker *mdata,
- void *probe_private, void *call_private, const char *fmt, va_list *args)
-{
-}
-//ust// EXPORT_SYMBOL_GPL(__mark_empty_function);
-
-/*
- * marker_probe_cb Callback that prepares the variable argument list for probes.
- * @mdata: pointer of type struct marker
- * @call_private: caller site private data
- * @...: Variable argument list.
- *
- * Since we do not use "typical" pointer based RCU in the 1 argument case, we
- * need to put a full smp_rmb() in this branch. This is why we do not use
- * rcu_dereference() for the pointer read.
- */
-notrace void marker_probe_cb(const struct marker *mdata,
- void *call_private, ...)
-{
- va_list args;
- char ptype;
-
- /*
- * rcu_read_lock_sched does two things : disabling preemption to make
- * sure the teardown of the callbacks can be done correctly when they
- * are in modules and they insure RCU read coherency.
- */
-//ust// rcu_read_lock_sched_notrace();
- ptype = mdata->ptype;
- if (likely(!ptype)) {
- marker_probe_func *func;
- /* Must read the ptype before ptr. They are not data dependant,
- * so we put an explicit smp_rmb() here. */
- smp_rmb();
- func = mdata->single.func;
- /* Must read the ptr before private data. They are not data
- * dependant, so we put an explicit smp_rmb() here. */
- smp_rmb();
- va_start(args, call_private);
- func(mdata, mdata->single.probe_private, call_private,
- mdata->format, &args);
- va_end(args);
- } else {
- struct marker_probe_closure *multi;
- int i;
- /*
- * Read mdata->ptype before mdata->multi.
- */
- smp_rmb();
- multi = mdata->multi;
- /*
- * multi points to an array, therefore accessing the array
- * depends on reading multi. However, even in this case,
- * we must insure that the pointer is read _before_ the array
- * data. Same as rcu_dereference, but we need a full smp_rmb()
- * in the fast path, so put the explicit barrier here.
- */
- smp_read_barrier_depends();
- for (i = 0; multi[i].func; i++) {
- va_start(args, call_private);
- multi[i].func(mdata, multi[i].probe_private,
- call_private, mdata->format, &args);
- va_end(args);
- }
- }
-//ust// rcu_read_unlock_sched_notrace();
-}
-//ust// EXPORT_SYMBOL_GPL(marker_probe_cb);
-
-/*
- * marker_probe_cb Callback that does not prepare the variable argument list.
- * @mdata: pointer of type struct marker
- * @call_private: caller site private data
- * @...: Variable argument list.
- *
- * Should be connected to markers "MARK_NOARGS".
- */
-static notrace void marker_probe_cb_noarg(const struct marker *mdata,
- void *call_private, ...)
-{
- va_list args; /* not initialized */
- char ptype;
-
-//ust// rcu_read_lock_sched_notrace();
- ptype = mdata->ptype;
- if (likely(!ptype)) {
- marker_probe_func *func;
- /* Must read the ptype before ptr. They are not data dependant,
- * so we put an explicit smp_rmb() here. */
- smp_rmb();
- func = mdata->single.func;
- /* Must read the ptr before private data. They are not data
- * dependant, so we put an explicit smp_rmb() here. */
- smp_rmb();
- func(mdata, mdata->single.probe_private, call_private,
- mdata->format, &args);
- } else {
- struct marker_probe_closure *multi;
- int i;
- /*
- * Read mdata->ptype before mdata->multi.
- */
- smp_rmb();
- multi = mdata->multi;
- /*
- * multi points to an array, therefore accessing the array
- * depends on reading multi. However, even in this case,
- * we must insure that the pointer is read _before_ the array
- * data. Same as rcu_dereference, but we need a full smp_rmb()
- * in the fast path, so put the explicit barrier here.
- */
- smp_read_barrier_depends();
- for (i = 0; multi[i].func; i++)
- multi[i].func(mdata, multi[i].probe_private,
- call_private, mdata->format, &args);
- }
-//ust// rcu_read_unlock_sched_notrace();
-}
-
-static void free_old_closure(struct rcu_head *head)
-{
- struct marker_entry *entry = container_of(head,
- struct marker_entry, rcu);
- kfree(entry->oldptr);
- /* Make sure we free the data before setting the pending flag to 0 */
- smp_wmb();
- entry->rcu_pending = 0;
-}
-
-static void debug_print_probes(struct marker_entry *entry)
-{
- int i;
-
- if (!marker_debug)
- return;
-
- if (!entry->ptype) {
- printk(KERN_DEBUG "Single probe : %p %p\n",
- entry->single.func,
- entry->single.probe_private);
- } else {
- for (i = 0; entry->multi[i].func; i++)
- printk(KERN_DEBUG "Multi probe %d : %p %p\n", i,
- entry->multi[i].func,
- entry->multi[i].probe_private);
- }
-}
-
-static struct marker_probe_closure *
-marker_entry_add_probe(struct marker_entry *entry,
- marker_probe_func *probe, void *probe_private)
-{
- int nr_probes = 0;
- struct marker_probe_closure *old, *new;
-
- WARN_ON(!probe);
-
- debug_print_probes(entry);
- old = entry->multi;
- if (!entry->ptype) {
- if (entry->single.func == probe &&
- entry->single.probe_private == probe_private)
- return ERR_PTR(-EBUSY);
- if (entry->single.func == __mark_empty_function) {
- /* 0 -> 1 probes */
- entry->single.func = probe;
- entry->single.probe_private = probe_private;
- entry->refcount = 1;
- entry->ptype = 0;
- debug_print_probes(entry);
- return NULL;
- } else {
- /* 1 -> 2 probes */
- nr_probes = 1;
- old = NULL;
- }
- } else {
- /* (N -> N+1), (N != 0, 1) probes */
- for (nr_probes = 0; old[nr_probes].func; nr_probes++)
- if (old[nr_probes].func == probe
- && old[nr_probes].probe_private
- == probe_private)
- return ERR_PTR(-EBUSY);
- }
- /* + 2 : one for new probe, one for NULL func */
- new = kzalloc((nr_probes + 2) * sizeof(struct marker_probe_closure),
- GFP_KERNEL);
- if (new == NULL)
- return ERR_PTR(-ENOMEM);
- if (!old)
- new[0] = entry->single;
- else
- memcpy(new, old,
- nr_probes * sizeof(struct marker_probe_closure));
- new[nr_probes].func = probe;
- new[nr_probes].probe_private = probe_private;
- entry->refcount = nr_probes + 1;
- entry->multi = new;
- entry->ptype = 1;
- debug_print_probes(entry);
- return old;
-}
-
-static struct marker_probe_closure *
-marker_entry_remove_probe(struct marker_entry *entry,
- marker_probe_func *probe, void *probe_private)
-{
- int nr_probes = 0, nr_del = 0, i;
- struct marker_probe_closure *old, *new;
-
- old = entry->multi;
-
- debug_print_probes(entry);
- if (!entry->ptype) {
- /* 0 -> N is an error */
- WARN_ON(entry->single.func == __mark_empty_function);
- /* 1 -> 0 probes */
- WARN_ON(probe && entry->single.func != probe);
- WARN_ON(entry->single.probe_private != probe_private);
- entry->single.func = __mark_empty_function;
- entry->refcount = 0;
- entry->ptype = 0;
- debug_print_probes(entry);
- return NULL;
- } else {
- /* (N -> M), (N > 1, M >= 0) probes */
- for (nr_probes = 0; old[nr_probes].func; nr_probes++) {
- if ((!probe || old[nr_probes].func == probe)
- && old[nr_probes].probe_private
- == probe_private)
- nr_del++;
- }
- }
-
- if (nr_probes - nr_del == 0) {
- /* N -> 0, (N > 1) */
- entry->single.func = __mark_empty_function;
- entry->refcount = 0;
- entry->ptype = 0;
- } else if (nr_probes - nr_del == 1) {
- /* N -> 1, (N > 1) */
- for (i = 0; old[i].func; i++)
- if ((probe && old[i].func != probe) ||
- old[i].probe_private != probe_private)
- entry->single = old[i];
- entry->refcount = 1;
- entry->ptype = 0;
- } else {
- int j = 0;
- /* N -> M, (N > 1, M > 1) */
- /* + 1 for NULL */
- new = kzalloc((nr_probes - nr_del + 1)
- * sizeof(struct marker_probe_closure), GFP_KERNEL);
- if (new == NULL)
- return ERR_PTR(-ENOMEM);
- for (i = 0; old[i].func; i++)
- if ((probe && old[i].func != probe) ||
- old[i].probe_private != probe_private)
- new[j++] = old[i];
- entry->refcount = nr_probes - nr_del;
- entry->ptype = 1;
- entry->multi = new;
- }
- debug_print_probes(entry);
- return old;
-}
-
-/*
- * Get marker if the marker is present in the marker hash table.
- * Must be called with markers_mutex held.
- * Returns NULL if not present.
- */
-static struct marker_entry *get_marker(const char *channel, const char *name)
-{
- struct hlist_head *head;
- struct hlist_node *node;
- struct marker_entry *e;
- size_t channel_len = strlen(channel) + 1;
- size_t name_len = strlen(name) + 1;
- u32 hash;
-
- hash = jhash(channel, channel_len-1, 0) ^ jhash(name, name_len-1, 0);
- head = &marker_table[hash & ((1 << MARKER_HASH_BITS)-1)];
- hlist_for_each_entry(e, node, head, hlist) {
- if (!strcmp(channel, e->channel) && !strcmp(name, e->name))
- return e;
- }
- return NULL;
-}
-
-/*
- * Add the marker to the marker hash table. Must be called with markers_mutex
- * held.
- */
-static struct marker_entry *add_marker(const char *channel, const char *name,
- const char *format)
-{
- struct hlist_head *head;
- struct hlist_node *node;
- struct marker_entry *e;
- size_t channel_len = strlen(channel) + 1;
- size_t name_len = strlen(name) + 1;
- size_t format_len = 0;
- u32 hash;
-
- hash = jhash(channel, channel_len-1, 0) ^ jhash(name, name_len-1, 0);
- if (format)
- format_len = strlen(format) + 1;
- head = &marker_table[hash & ((1 << MARKER_HASH_BITS)-1)];
- hlist_for_each_entry(e, node, head, hlist) {
- if (!strcmp(channel, e->channel) && !strcmp(name, e->name)) {
- printk(KERN_NOTICE
- "Marker %s.%s busy\n", channel, name);
- return ERR_PTR(-EBUSY); /* Already there */
- }
- }
- /*
- * Using kmalloc here to allocate a variable length element. Could
- * cause some memory fragmentation if overused.
- */
- e = kmalloc(sizeof(struct marker_entry)
- + channel_len + name_len + format_len,
- GFP_KERNEL);
- if (!e)
- return ERR_PTR(-ENOMEM);
- memcpy(e->channel, channel, channel_len);
- e->name = &e->channel[channel_len];
- memcpy(e->name, name, name_len);
- if (format) {
- e->format = &e->name[channel_len + name_len];
- memcpy(e->format, format, format_len);
- if (strcmp(e->format, MARK_NOARGS) == 0)
- e->call = marker_probe_cb_noarg;
- else
- e->call = marker_probe_cb;
- trace_mark(metadata, core_marker_format,
- "channel %s name %s format %s",
- e->channel, e->name, e->format);
- } else {
- e->format = NULL;
- e->call = marker_probe_cb;
- }
- e->single.func = __mark_empty_function;
- e->single.probe_private = NULL;
- e->multi = NULL;
- e->ptype = 0;
- e->format_allocated = 0;
- e->refcount = 0;
- e->rcu_pending = 0;
- hlist_add_head(&e->hlist, head);
- return e;
-}
-
-/*
- * Remove the marker from the marker hash table. Must be called with mutex_lock
- * held.
- */
-static int remove_marker(const char *channel, const char *name)
-{
- struct hlist_head *head;
- struct hlist_node *node;
- struct marker_entry *e;
- int found = 0;
- size_t channel_len = strlen(channel) + 1;
- size_t name_len = strlen(name) + 1;
- u32 hash;
- int ret;
-
- hash = jhash(channel, channel_len-1, 0) ^ jhash(name, name_len-1, 0);
- head = &marker_table[hash & ((1 << MARKER_HASH_BITS)-1)];
- hlist_for_each_entry(e, node, head, hlist) {
- if (!strcmp(channel, e->channel) && !strcmp(name, e->name)) {
- found = 1;
- break;
- }
- }
- if (!found)
- return -ENOENT;
- if (e->single.func != __mark_empty_function)
- return -EBUSY;
- hlist_del(&e->hlist);
- if (e->format_allocated)
- kfree(e->format);
- ret = ltt_channels_unregister(e->channel);
- WARN_ON(ret);
- /* Make sure the call_rcu has been executed */
- if (e->rcu_pending)
- rcu_barrier_sched();
- kfree(e);
- return 0;
-}
-
-/*
- * Set the mark_entry format to the format found in the element.
- */
-static int marker_set_format(struct marker_entry *entry, const char *format)
-{
- entry->format = kstrdup(format, GFP_KERNEL);
- if (!entry->format)
- return -ENOMEM;
- entry->format_allocated = 1;
-
- trace_mark(metadata, core_marker_format,
- "channel %s name %s format %s",
- entry->channel, entry->name, entry->format);
- return 0;
-}
-
-/*
- * Sets the probe callback corresponding to one marker.
- */
-static int set_marker(struct marker_entry *entry, struct marker *elem,
- int active)
-{
- int ret = 0;
- WARN_ON(strcmp(entry->name, elem->name) != 0);
-
- if (entry->format) {
- if (strcmp(entry->format, elem->format) != 0) {
- printk(KERN_NOTICE
- "Format mismatch for probe %s "
- "(%s), marker (%s)\n",
- entry->name,
- entry->format,
- elem->format);
- return -EPERM;
- }
- } else {
- ret = marker_set_format(entry, elem->format);
- if (ret)
- return ret;
- }
-
- /*
- * probe_cb setup (statically known) is done here. It is
- * asynchronous with the rest of execution, therefore we only
- * pass from a "safe" callback (with argument) to an "unsafe"
- * callback (does not set arguments).
- */
- elem->call = entry->call;
- elem->channel_id = entry->channel_id;
- elem->event_id = entry->event_id;
- /*
- * Sanity check :
- * We only update the single probe private data when the ptr is
- * set to a _non_ single probe! (0 -> 1 and N -> 1, N != 1)
- */
- WARN_ON(elem->single.func != __mark_empty_function
- && elem->single.probe_private != entry->single.probe_private
- && !elem->ptype);
- elem->single.probe_private = entry->single.probe_private;
- /*
- * Make sure the private data is valid when we update the
- * single probe ptr.
- */
- smp_wmb();
- elem->single.func = entry->single.func;
- /*
- * We also make sure that the new probe callbacks array is consistent
- * before setting a pointer to it.
- */
- rcu_assign_pointer(elem->multi, entry->multi);
- /*
- * Update the function or multi probe array pointer before setting the
- * ptype.
- */
- smp_wmb();
- elem->ptype = entry->ptype;
-
-//ust// if (elem->tp_name && (active ^ _imv_read(elem->state))) {
-//ust// WARN_ON(!elem->tp_cb);
-//ust// /*
-//ust// * It is ok to directly call the probe registration because type
-//ust// * checking has been done in the __trace_mark_tp() macro.
-//ust// */
-//ust//
-//ust// if (active) {
-//ust// /*
-//ust// * try_module_get should always succeed because we hold
-//ust// * markers_mutex to get the tp_cb address.
-//ust// */
-//ust// ret = try_module_get(__module_text_address(
-//ust// (unsigned long)elem->tp_cb));
-//ust// BUG_ON(!ret);
-//ust// ret = tracepoint_probe_register_noupdate(
-//ust// elem->tp_name,
-//ust// elem->tp_cb);
-//ust// } else {
-//ust// ret = tracepoint_probe_unregister_noupdate(
-//ust// elem->tp_name,
-//ust// elem->tp_cb);
-//ust// /*
-//ust// * tracepoint_probe_update_all() must be called
-//ust// * before the module containing tp_cb is unloaded.
-//ust// */
-//ust// module_put(__module_text_address(
-//ust// (unsigned long)elem->tp_cb));
-//ust// }
-//ust// }
- elem->state__imv = active;
-
- return ret;
-}
-
-/*
- * Disable a marker and its probe callback.
- * Note: only waiting an RCU period after setting elem->call to the empty
- * function insures that the original callback is not used anymore. This insured
- * by rcu_read_lock_sched around the call site.
- */
-static void disable_marker(struct marker *elem)
-{
- int ret;
-
- /* leave "call" as is. It is known statically. */
-//ust// if (elem->tp_name && _imv_read(elem->state)) {
-//ust// WARN_ON(!elem->tp_cb);
-//ust// /*
-//ust// * It is ok to directly call the probe registration because type
-//ust// * checking has been done in the __trace_mark_tp() macro.
-//ust// */
-//ust// ret = tracepoint_probe_unregister_noupdate(elem->tp_name,
-//ust// elem->tp_cb);
-//ust// WARN_ON(ret);
-//ust// /*
-//ust// * tracepoint_probe_update_all() must be called
-//ust// * before the module containing tp_cb is unloaded.
-//ust// */
-//ust// module_put(__module_text_address((unsigned long)elem->tp_cb));
-//ust// }
- elem->state__imv = 0;
- elem->single.func = __mark_empty_function;
- /* Update the function before setting the ptype */
- smp_wmb();
- elem->ptype = 0; /* single probe */
- /*
- * Leave the private data and channel_id/event_id there, because removal
- * is racy and should be done only after an RCU period. These are never
- * used until the next initialization anyway.
- */
-}
-
-/**
- * marker_update_probe_range - Update a probe range
- * @begin: beginning of the range
- * @end: end of the range
- *
- * Updates the probe callback corresponding to a range of markers.
- */
-void marker_update_probe_range(struct marker *begin,
- struct marker *end)
-{
- struct marker *iter;
- struct marker_entry *mark_entry;
-
- mutex_lock(&markers_mutex);
- for (iter = begin; iter < end; iter++) {
- mark_entry = get_marker(iter->channel, iter->name);
- if (mark_entry) {
- set_marker(mark_entry, iter, !!mark_entry->refcount);
- /*
- * ignore error, continue
- */
-
- /* This is added for UST. We emit a core_marker_id event
- * for markers that are already registered to a probe
- * upon library load. Otherwise, no core_marker_id will
- * be generated for these markers. Is this the right thing
- * to do?
- */
- trace_mark(metadata, core_marker_id,
- "channel %s name %s event_id %hu "
- "int #1u%zu long #1u%zu pointer #1u%zu "
- "size_t #1u%zu alignment #1u%u",
- iter->channel, iter->name, mark_entry->event_id,
- sizeof(int), sizeof(long), sizeof(void *),
- sizeof(size_t), ltt_get_alignment());
- } else {
- disable_marker(iter);
- }
- }
- mutex_unlock(&markers_mutex);
-}
-
-/*
- * Update probes, removing the faulty probes.
- *
- * Internal callback only changed before the first probe is connected to it.
- * Single probe private data can only be changed on 0 -> 1 and 2 -> 1
- * transitions. All other transitions will leave the old private data valid.
- * This makes the non-atomicity of the callback/private data updates valid.
- *
- * "special case" updates :
- * 0 -> 1 callback
- * 1 -> 0 callback
- * 1 -> 2 callbacks
- * 2 -> 1 callbacks
- * Other updates all behave the same, just like the 2 -> 3 or 3 -> 2 updates.
- * Site effect : marker_set_format may delete the marker entry (creating a
- * replacement).
- */
-static void marker_update_probes(void)
-{
- /* Core kernel markers */
-//ust// marker_update_probe_range(__start___markers, __stop___markers);
- /* Markers in modules. */
-//ust// module_update_markers();
- lib_update_markers();
-//ust// tracepoint_probe_update_all();
- /* Update immediate values */
- core_imv_update();
-//ust// module_imv_update(); /* FIXME: need to port for libs? */
- marker_update_processes();
-}
-
-/**
- * marker_probe_register - Connect a probe to a marker
- * @channel: marker channel
- * @name: marker name
- * @format: format string
- * @probe: probe handler
- * @probe_private: probe private data
- *
- * private data must be a valid allocated memory address, or NULL.
- * Returns 0 if ok, error value on error.
- * The probe address must at least be aligned on the architecture pointer size.
- */
-int marker_probe_register(const char *channel, const char *name,
- const char *format, marker_probe_func *probe,
- void *probe_private)
-{
- struct marker_entry *entry;
- int ret = 0, ret_err;
- struct marker_probe_closure *old;
- int first_probe = 0;
-
- mutex_lock(&markers_mutex);
- entry = get_marker(channel, name);
- if (!entry) {
- first_probe = 1;
- entry = add_marker(channel, name, format);
- if (IS_ERR(entry))
- ret = PTR_ERR(entry);
- if (ret)
- goto end;
- ret = ltt_channels_register(channel);
- if (ret)
- goto error_remove_marker;
- ret = ltt_channels_get_index_from_name(channel);
- if (ret < 0)
- goto error_unregister_channel;
- entry->channel_id = ret;
- ret = ltt_channels_get_event_id(channel, name);
- if (ret < 0)
- goto error_unregister_channel;
- entry->event_id = ret;
- ret = 0;
- trace_mark(metadata, core_marker_id,
- "channel %s name %s event_id %hu "
- "int #1u%zu long #1u%zu pointer #1u%zu "
- "size_t #1u%zu alignment #1u%u",
- channel, name, entry->event_id,
- sizeof(int), sizeof(long), sizeof(void *),
- sizeof(size_t), ltt_get_alignment());
- } else if (format) {
- if (!entry->format)
- ret = marker_set_format(entry, format);
- else if (strcmp(entry->format, format))
- ret = -EPERM;
- if (ret)
- goto end;
- }
-
- /*
- * If we detect that a call_rcu is pending for this marker,
- * make sure it's executed now.
- */
- if (entry->rcu_pending)
- rcu_barrier_sched();
- old = marker_entry_add_probe(entry, probe, probe_private);
- if (IS_ERR(old)) {
- ret = PTR_ERR(old);
- if (first_probe)
- goto error_unregister_channel;
- else
- goto end;
- }
- mutex_unlock(&markers_mutex);
-
- marker_update_probes();
-
- mutex_lock(&markers_mutex);
- entry = get_marker(channel, name);
- if (!entry)
- goto end;
- if (entry->rcu_pending)
- rcu_barrier_sched();
- entry->oldptr = old;
- entry->rcu_pending = 1;
- /* write rcu_pending before calling the RCU callback */
- smp_wmb();
- call_rcu_sched(&entry->rcu, free_old_closure);
- /*synchronize_rcu(); free_old_closure();*/
- goto end;
-
-error_unregister_channel:
- ret_err = ltt_channels_unregister(channel);
- WARN_ON(ret_err);
-error_remove_marker:
- ret_err = remove_marker(channel, name);
- WARN_ON(ret_err);
-end:
- mutex_unlock(&markers_mutex);
- return ret;
-}
-//ust// EXPORT_SYMBOL_GPL(marker_probe_register);
-
-/**
- * marker_probe_unregister - Disconnect a probe from a marker
- * @channel: marker channel
- * @name: marker name
- * @probe: probe function pointer
- * @probe_private: probe private data
- *
- * Returns the private data given to marker_probe_register, or an ERR_PTR().
- * We do not need to call a synchronize_sched to make sure the probes have
- * finished running before doing a module unload, because the module unload
- * itself uses stop_machine(), which insures that every preempt disabled section
- * have finished.
- */
-int marker_probe_unregister(const char *channel, const char *name,
- marker_probe_func *probe, void *probe_private)
-{
- struct marker_entry *entry;
- struct marker_probe_closure *old;
- int ret = -ENOENT;
-
- mutex_lock(&markers_mutex);
- entry = get_marker(channel, name);
- if (!entry)
- goto end;
- if (entry->rcu_pending)
- rcu_barrier_sched();
- old = marker_entry_remove_probe(entry, probe, probe_private);
- mutex_unlock(&markers_mutex);
-
- marker_update_probes();
-
- mutex_lock(&markers_mutex);
- entry = get_marker(channel, name);
- if (!entry)
- goto end;
- if (entry->rcu_pending)
- rcu_barrier_sched();
- entry->oldptr = old;
- entry->rcu_pending = 1;
- /* write rcu_pending before calling the RCU callback */
- smp_wmb();
- call_rcu_sched(&entry->rcu, free_old_closure);
- remove_marker(channel, name); /* Ignore busy error message */
- ret = 0;
-end:
- mutex_unlock(&markers_mutex);
- return ret;
-}
-//ust// EXPORT_SYMBOL_GPL(marker_probe_unregister);
-
-static struct marker_entry *
-get_marker_from_private_data(marker_probe_func *probe, void *probe_private)
-{
- struct marker_entry *entry;
- unsigned int i;
- struct hlist_head *head;
- struct hlist_node *node;
-
- for (i = 0; i < MARKER_TABLE_SIZE; i++) {
- head = &marker_table[i];
- hlist_for_each_entry(entry, node, head, hlist) {
- if (!entry->ptype) {
- if (entry->single.func == probe
- && entry->single.probe_private
- == probe_private)
- return entry;
- } else {
- struct marker_probe_closure *closure;
- closure = entry->multi;
- for (i = 0; closure[i].func; i++) {
- if (closure[i].func == probe &&
- closure[i].probe_private
- == probe_private)
- return entry;
- }
- }
- }
- }
- return NULL;
-}
-
-/**
- * marker_probe_unregister_private_data - Disconnect a probe from a marker
- * @probe: probe function
- * @probe_private: probe private data
- *
- * Unregister a probe by providing the registered private data.
- * Only removes the first marker found in hash table.
- * Return 0 on success or error value.
- * We do not need to call a synchronize_sched to make sure the probes have
- * finished running before doing a module unload, because the module unload
- * itself uses stop_machine(), which insures that every preempt disabled section
- * have finished.
- */
-int marker_probe_unregister_private_data(marker_probe_func *probe,
- void *probe_private)
-{
- struct marker_entry *entry;
- int ret = 0;
- struct marker_probe_closure *old;
- const char *channel = NULL, *name = NULL;
-
- mutex_lock(&markers_mutex);
- entry = get_marker_from_private_data(probe, probe_private);
- if (!entry) {
- ret = -ENOENT;
- goto end;
- }
- if (entry->rcu_pending)
- rcu_barrier_sched();
- old = marker_entry_remove_probe(entry, NULL, probe_private);
- channel = kstrdup(entry->channel, GFP_KERNEL);
- name = kstrdup(entry->name, GFP_KERNEL);
- mutex_unlock(&markers_mutex);
-
- marker_update_probes();
-
- mutex_lock(&markers_mutex);
- entry = get_marker(channel, name);
- if (!entry)
- goto end;
- if (entry->rcu_pending)
- rcu_barrier_sched();
- entry->oldptr = old;
- entry->rcu_pending = 1;
- /* write rcu_pending before calling the RCU callback */
- smp_wmb();
- call_rcu_sched(&entry->rcu, free_old_closure);
- /* Ignore busy error message */
- remove_marker(channel, name);
-end:
- mutex_unlock(&markers_mutex);
- kfree(channel);
- kfree(name);
- return ret;
-}
-//ust// EXPORT_SYMBOL_GPL(marker_probe_unregister_private_data);
-
-/**
- * marker_get_private_data - Get a marker's probe private data
- * @channel: marker channel
- * @name: marker name
- * @probe: probe to match
- * @num: get the nth matching probe's private data
- *
- * Returns the nth private data pointer (starting from 0) matching, or an
- * ERR_PTR.
- * Returns the private data pointer, or an ERR_PTR.
- * The private data pointer should _only_ be dereferenced if the caller is the
- * owner of the data, or its content could vanish. This is mostly used to
- * confirm that a caller is the owner of a registered probe.
- */
-void *marker_get_private_data(const char *channel, const char *name,
- marker_probe_func *probe, int num)
-{
- struct hlist_head *head;
- struct hlist_node *node;
- struct marker_entry *e;
- size_t channel_len = strlen(channel) + 1;
- size_t name_len = strlen(name) + 1;
- int i;
- u32 hash;
-
- hash = jhash(channel, channel_len-1, 0) ^ jhash(name, name_len-1, 0);
- head = &marker_table[hash & ((1 << MARKER_HASH_BITS)-1)];
- hlist_for_each_entry(e, node, head, hlist) {
- if (!strcmp(channel, e->channel) && !strcmp(name, e->name)) {
- if (!e->ptype) {
- if (num == 0 && e->single.func == probe)
- return e->single.probe_private;
- } else {
- struct marker_probe_closure *closure;
- int match = 0;
- closure = e->multi;
- for (i = 0; closure[i].func; i++) {
- if (closure[i].func != probe)
- continue;
- if (match++ == num)
- return closure[i].probe_private;
- }
- }
- break;
- }
- }
- return ERR_PTR(-ENOENT);
-}
-//ust// EXPORT_SYMBOL_GPL(marker_get_private_data);
-
-/**
- * markers_compact_event_ids - Compact markers event IDs and reassign channels
- *
- * Called when no channel users are active by the channel infrastructure.
- * Called with lock_markers() and channel mutex held.
- */
-//ust// void markers_compact_event_ids(void)
-//ust// {
-//ust// struct marker_entry *entry;
-//ust// unsigned int i;
-//ust// struct hlist_head *head;
-//ust// struct hlist_node *node;
-//ust// int ret;
-//ust//
-//ust// for (i = 0; i < MARKER_TABLE_SIZE; i++) {
-//ust// head = &marker_table[i];
-//ust// hlist_for_each_entry(entry, node, head, hlist) {
-//ust// ret = ltt_channels_get_index_from_name(entry->channel);
-//ust// WARN_ON(ret < 0);
-//ust// entry->channel_id = ret;
-//ust// ret = _ltt_channels_get_event_id(entry->channel,
-//ust// entry->name);
-//ust// WARN_ON(ret < 0);
-//ust// entry->event_id = ret;
-//ust// }
-//ust// }
-//ust// }
-
-//ust//#ifdef CONFIG_MODULES
-
-/**
- * marker_get_iter_range - Get a next marker iterator given a range.
- * @marker: current markers (in), next marker (out)
- * @begin: beginning of the range
- * @end: end of the range
- *
- * Returns whether a next marker has been found (1) or not (0).
- * Will return the first marker in the range if the input marker is NULL.
- */
-int marker_get_iter_range(struct marker **marker, struct marker *begin,
- struct marker *end)
-{
- if (!*marker && begin != end) {
- *marker = begin;
- return 1;
- }
- if (*marker >= begin && *marker < end)
- return 1;
- return 0;
-}
-//ust// EXPORT_SYMBOL_GPL(marker_get_iter_range);
-
-static void marker_get_iter(struct marker_iter *iter)
-{
- int found = 0;
-
- /* Core kernel markers */
- if (!iter->lib) {
- /* ust FIXME: how come we cannot disable the following line? we shouldn't need core stuff */
- found = marker_get_iter_range(&iter->marker,
- __start___markers, __stop___markers);
- if (found)
- goto end;
- }
- /* Markers in modules. */
- found = lib_get_iter_markers(iter);
-end:
- if (!found)
- marker_iter_reset(iter);
-}
-
-void marker_iter_start(struct marker_iter *iter)
-{
- marker_get_iter(iter);
-}
-//ust// EXPORT_SYMBOL_GPL(marker_iter_start);
-
-void marker_iter_next(struct marker_iter *iter)
-{
- iter->marker++;
- /*
- * iter->marker may be invalid because we blindly incremented it.
- * Make sure it is valid by marshalling on the markers, getting the
- * markers from following modules if necessary.
- */
- marker_get_iter(iter);
-}
-//ust// EXPORT_SYMBOL_GPL(marker_iter_next);
-
-void marker_iter_stop(struct marker_iter *iter)
-{
-}
-//ust// EXPORT_SYMBOL_GPL(marker_iter_stop);
-
-void marker_iter_reset(struct marker_iter *iter)
-{
- iter->lib = NULL;
- iter->marker = NULL;
-}
-//ust// EXPORT_SYMBOL_GPL(marker_iter_reset);
-
-#ifdef CONFIG_MARKERS_USERSPACE
-/*
- * must be called with current->user_markers_mutex held
- */
-static void free_user_marker(char __user *state, struct hlist_head *head)
-{
- struct user_marker *umark;
- struct hlist_node *pos, *n;
-
- hlist_for_each_entry_safe(umark, pos, n, head, hlist) {
- if (umark->state == state) {
- hlist_del(&umark->hlist);
- kfree(umark);
- }
- }
-}
-
-//ust// asmlinkage long sys_marker(char __user *name, char __user *format,
-//ust// char __user *state, int reg)
-//ust// {
-//ust// struct user_marker *umark;
-//ust// long len;
-//ust// struct marker_entry *entry;
-//ust// int ret = 0;
-//ust//
-//ust// printk(KERN_DEBUG "Program %s %s marker [%p, %p]\n",
-//ust// current->comm, reg ? "registers" : "unregisters",
-//ust// name, state);
-//ust// if (reg) {
-//ust// umark = kmalloc(sizeof(struct user_marker), GFP_KERNEL);
-//ust// umark->name[MAX_USER_MARKER_NAME_LEN - 1] = '\0';
-//ust// umark->format[MAX_USER_MARKER_FORMAT_LEN - 1] = '\0';
-//ust// umark->state = state;
-//ust// len = strncpy_from_user(umark->name, name,
-//ust// MAX_USER_MARKER_NAME_LEN - 1);
-//ust// if (len < 0) {
-//ust// ret = -EFAULT;
-//ust// goto error;
-//ust// }
-//ust// len = strncpy_from_user(umark->format, format,
-//ust// MAX_USER_MARKER_FORMAT_LEN - 1);
-//ust// if (len < 0) {
-//ust// ret = -EFAULT;
-//ust// goto error;
-//ust// }
-//ust// printk(KERN_DEBUG "Marker name : %s, format : %s", umark->name,
-//ust// umark->format);
-//ust// mutex_lock(&markers_mutex);
-//ust// entry = get_marker("userspace", umark->name);
-//ust// if (entry) {
-//ust// if (entry->format &&
-//ust// strcmp(entry->format, umark->format) != 0) {
-//ust// printk(" error, wrong format in process %s",
-//ust// current->comm);
-//ust// ret = -EPERM;
-//ust// goto error_unlock;
-//ust// }
-//ust// printk(" %s", !!entry->refcount
-//ust// ? "enabled" : "disabled");
-//ust// if (put_user(!!entry->refcount, state)) {
-//ust// ret = -EFAULT;
-//ust// goto error_unlock;
-//ust// }
-//ust// printk("\n");
-//ust// } else {
-//ust// printk(" disabled\n");
-//ust// if (put_user(0, umark->state)) {
-//ust// printk(KERN_WARNING
-//ust// "Marker in %s caused a fault\n",
-//ust// current->comm);
-//ust// goto error_unlock;
-//ust// }
-//ust// }
-//ust// mutex_lock(¤t->group_leader->user_markers_mutex);
-//ust// hlist_add_head(&umark->hlist,
-//ust// ¤t->group_leader->user_markers);
-//ust// current->group_leader->user_markers_sequence++;
-//ust// mutex_unlock(¤t->group_leader->user_markers_mutex);
-//ust// mutex_unlock(&markers_mutex);
-//ust// } else {
-//ust// mutex_lock(¤t->group_leader->user_markers_mutex);
-//ust// free_user_marker(state,
-//ust// ¤t->group_leader->user_markers);
-//ust// current->group_leader->user_markers_sequence++;
-//ust// mutex_unlock(¤t->group_leader->user_markers_mutex);
-//ust// }
-//ust// goto end;
-//ust// error_unlock:
-//ust// mutex_unlock(&markers_mutex);
-//ust// error:
-//ust// kfree(umark);
-//ust// end:
-//ust// return ret;
-//ust// }
-//ust//
-//ust// /*
-//ust// * Types :
-//ust// * string : 0
-//ust// */
-//ust// asmlinkage long sys_trace(int type, uint16_t id,
-//ust// char __user *ubuf)
-//ust// {
-//ust// long ret = -EPERM;
-//ust// char *page;
-//ust// int len;
-//ust//
-//ust// switch (type) {
-//ust// case 0: /* String */
-//ust// ret = -ENOMEM;
-//ust// page = (char *)__get_free_page(GFP_TEMPORARY);
-//ust// if (!page)
-//ust// goto string_out;
-//ust// len = strncpy_from_user(page, ubuf, PAGE_SIZE);
-//ust// if (len < 0) {
-//ust// ret = -EFAULT;
-//ust// goto string_err;
-//ust// }
-//ust// trace_mark(userspace, string, "string %s", page);
-//ust// string_err:
-//ust// free_page((unsigned long) page);
-//ust// string_out:
-//ust// break;
-//ust// default:
-//ust// break;
-//ust// }
-//ust// return ret;
-//ust// }
-
-//ust// static void marker_update_processes(void)
-//ust// {
-//ust// struct task_struct *g, *t;
-//ust//
-//ust// /*
-//ust// * markers_mutex is taken to protect the p->user_markers read.
-//ust// */
-//ust// mutex_lock(&markers_mutex);
-//ust// read_lock(&tasklist_lock);
-//ust// for_each_process(g) {
-//ust// WARN_ON(!thread_group_leader(g));
-//ust// if (hlist_empty(&g->user_markers))
-//ust// continue;
-//ust// if (strcmp(g->comm, "testprog") == 0)
-//ust// printk(KERN_DEBUG "set update pending for testprog\n");
-//ust// t = g;
-//ust// do {
-//ust// /* TODO : implement this thread flag in each arch. */
-//ust// set_tsk_thread_flag(t, TIF_MARKER_PENDING);
-//ust// } while ((t = next_thread(t)) != g);
-//ust// }
-//ust// read_unlock(&tasklist_lock);
-//ust// mutex_unlock(&markers_mutex);
-//ust// }
-
-/*
- * Update current process.
- * Note that we have to wait a whole scheduler period before we are sure that
- * every running userspace threads have their markers updated.
- * (synchronize_sched() can be used to insure this).
- */
-void marker_update_process(void)
-{
- struct user_marker *umark;
- struct hlist_node *pos;
- struct marker_entry *entry;
-
- mutex_lock(&markers_mutex);
- mutex_lock(¤t->group_leader->user_markers_mutex);
- if (strcmp(current->comm, "testprog") == 0)
- printk(KERN_DEBUG "do update pending for testprog\n");
- hlist_for_each_entry(umark, pos,
- ¤t->group_leader->user_markers, hlist) {
- printk(KERN_DEBUG "Updating marker %s in %s\n",
- umark->name, current->comm);
- entry = get_marker("userspace", umark->name);
- if (entry) {
- if (entry->format &&
- strcmp(entry->format, umark->format) != 0) {
- printk(KERN_WARNING
- " error, wrong format in process %s\n",
- current->comm);
- break;
- }
- if (put_user(!!entry->refcount, umark->state)) {
- printk(KERN_WARNING
- "Marker in %s caused a fault\n",
- current->comm);
- break;
- }
- } else {
- if (put_user(0, umark->state)) {
- printk(KERN_WARNING
- "Marker in %s caused a fault\n",
- current->comm);
- break;
- }
- }
- }
- clear_thread_flag(TIF_MARKER_PENDING);
- mutex_unlock(¤t->group_leader->user_markers_mutex);
- mutex_unlock(&markers_mutex);
-}
-
-/*
- * Called at process exit and upon do_execve().
- * We assume that when the leader exits, no more references can be done to the
- * leader structure by the other threads.
- */
-void exit_user_markers(struct task_struct *p)
-{
- struct user_marker *umark;
- struct hlist_node *pos, *n;
-
- if (thread_group_leader(p)) {
- mutex_lock(&markers_mutex);
- mutex_lock(&p->user_markers_mutex);
- hlist_for_each_entry_safe(umark, pos, n, &p->user_markers,
- hlist)
- kfree(umark);
- INIT_HLIST_HEAD(&p->user_markers);
- p->user_markers_sequence++;
- mutex_unlock(&p->user_markers_mutex);
- mutex_unlock(&markers_mutex);
- }
-}
-
-int is_marker_enabled(const char *channel, const char *name)
-{
- struct marker_entry *entry;
-
- mutex_lock(&markers_mutex);
- entry = get_marker(channel, name);
- mutex_unlock(&markers_mutex);
-
- return entry && !!entry->refcount;
-}
-//ust// #endif
-
-int marker_module_notify(struct notifier_block *self,
- unsigned long val, void *data)
-{
- struct module *mod = data;
-
- switch (val) {
- case MODULE_STATE_COMING:
- marker_update_probe_range(mod->markers,
- mod->markers + mod->num_markers);
- break;
- case MODULE_STATE_GOING:
- marker_update_probe_range(mod->markers,
- mod->markers + mod->num_markers);
- break;
- }
- return 0;
-}
-
-struct notifier_block marker_module_nb = {
- .notifier_call = marker_module_notify,
- .priority = 0,
-};
-
-//ust// static int init_markers(void)
-//ust// {
-//ust// return register_module_notifier(&marker_module_nb);
-//ust// }
-//ust// __initcall(init_markers);
-/* TODO: call marker_module_nb() when a library is linked at runtime (dlopen)? */
-
-#endif /* CONFIG_MODULES */
-
-void ltt_dump_marker_state(struct ltt_trace_struct *trace)
-{
- struct marker_iter iter;
- struct ltt_probe_private_data call_data;
- const char *channel;
-
- call_data.trace = trace;
- call_data.serializer = NULL;
-
- marker_iter_reset(&iter);
- marker_iter_start(&iter);
- for (; iter.marker != NULL; marker_iter_next(&iter)) {
- if (!_imv_read(iter.marker->state))
- continue;
- channel = ltt_channels_get_name_from_index(
- iter.marker->channel_id);
- __trace_mark(0, metadata, core_marker_id,
- &call_data,
- "channel %s name %s event_id %hu "
- "int #1u%zu long #1u%zu pointer #1u%zu "
- "size_t #1u%zu alignment #1u%u",
- channel,
- iter.marker->name,
- iter.marker->event_id,
- sizeof(int), sizeof(long),
- sizeof(void *), sizeof(size_t),
- ltt_get_alignment());
- if (iter.marker->format)
- __trace_mark(0, metadata,
- core_marker_format,
- &call_data,
- "channel %s name %s format %s",
- channel,
- iter.marker->name,
- iter.marker->format);
- }
- marker_iter_stop(&iter);
-}
-//ust// EXPORT_SYMBOL_GPL(ltt_dump_marker_state);
-
-
-static LIST_HEAD(libs);
-
-/*
- * Returns 0 if current not found.
- * Returns 1 if current found.
- */
-int lib_get_iter_markers(struct marker_iter *iter)
-{
- struct lib *iter_lib;
- int found = 0;
-
-//ust// mutex_lock(&module_mutex);
- list_for_each_entry(iter_lib, &libs, list) {
- if (iter_lib < iter->lib)
- continue;
- else if (iter_lib > iter->lib)
- iter->marker = NULL;
- found = marker_get_iter_range(&iter->marker,
- iter_lib->markers_start,
- iter_lib->markers_start + iter_lib->markers_count);
- if (found) {
- iter->lib = iter_lib;
- break;
- }
- }
-//ust// mutex_unlock(&module_mutex);
- return found;
-}
-
-void lib_update_markers(void)
-{
- struct lib *lib;
-
-//ust// mutex_lock(&module_mutex);
- list_for_each_entry(lib, &libs, list)
- marker_update_probe_range(lib->markers_start,
- lib->markers_start + lib->markers_count);
-//ust// mutex_unlock(&module_mutex);
-}
-
-static void (*new_marker_cb)(struct marker *) = NULL;
-
-void marker_set_new_marker_cb(void (*cb)(struct marker *))
-{
- new_marker_cb = cb;
-}
-
-static void new_markers(struct marker *start, struct marker *end)
-{
- if(new_marker_cb) {
- struct marker *m;
- for(m=start; m < end; m++) {
- new_marker_cb(m);
- }
- }
-}
-
-int marker_register_lib(struct marker *markers_start, int markers_count)
-{
- struct lib *pl;
-
- pl = (struct lib *) malloc(sizeof(struct lib));
-
- pl->markers_start = markers_start;
- pl->markers_count = markers_count;
-
- /* FIXME: maybe protect this with its own mutex? */
- lock_markers();
- list_add(&pl->list, &libs);
- unlock_markers();
-
- new_markers(markers_start, markers_start + markers_count);
-
- /* FIXME: update just the loaded lib */
- lib_update_markers();
-
- DBG("just registered a markers section from %p and having %d markers", markers_start, markers_count);
-
- return 0;
-}
-
-int marker_unregister_lib(struct marker *markers_start, int markers_count)
-{
- /*FIXME: implement; but before implementing, marker_register_lib must
- have appropriate locking. */
-
- return 0;
-}
-
-static int initialized = 0;
-
-void __attribute__((constructor)) init_markers(void)
-{
- if(!initialized) {
- marker_register_lib(__start___markers, (((long)__stop___markers)-((long)__start___markers))/sizeof(struct marker));
- printf("markers_start: %p, markers_stop: %p\n", __start___markers, __stop___markers);
- initialized = 1;
- }
-}
projects / ust.git / blobdiff