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-rw-r--r--kernel/Makefile1
-rw-r--r--kernel/marker.c930
-rw-r--r--kernel/module.c18
-rw-r--r--kernel/profile.c45
-rw-r--r--kernel/rcupdate.c48
-rw-r--r--kernel/rcutorture.c43
-rw-r--r--kernel/rcutree.c105
-rw-r--r--kernel/rcutree.h2
-rw-r--r--kernel/rcutree_plugin.h110
-rw-r--r--kernel/rcutree_trace.c2
-rw-r--r--kernel/sched.c29
-rw-r--r--kernel/sched_fair.c65
-rw-r--r--kernel/sched_idletask.c7
-rw-r--r--kernel/sched_rt.c13
-rw-r--r--kernel/trace/ftrace.c23
-rw-r--r--kernel/trace/trace.c57
-rw-r--r--kernel/trace/trace_event_profile.c82
-rw-r--r--kernel/trace/trace_events.c49
-rw-r--r--kernel/trace/trace_printk.c1
-rw-r--r--kernel/trace/trace_syscalls.c97
20 files changed, 471 insertions, 1256 deletions
diff --git a/kernel/Makefile b/kernel/Makefile
index e26a546..187c89b 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -87,7 +87,6 @@ obj-$(CONFIG_RELAY) += relay.o
obj-$(CONFIG_SYSCTL) += utsname_sysctl.o
obj-$(CONFIG_TASK_DELAY_ACCT) += delayacct.o
obj-$(CONFIG_TASKSTATS) += taskstats.o tsacct.o
-obj-$(CONFIG_MARKERS) += marker.o
obj-$(CONFIG_TRACEPOINTS) += tracepoint.o
obj-$(CONFIG_LATENCYTOP) += latencytop.o
obj-$(CONFIG_FUNCTION_TRACER) += trace/
diff --git a/kernel/marker.c b/kernel/marker.c
deleted file mode 100644
index ea54f26..0000000
--- a/kernel/marker.c
+++ /dev/null
@@ -1,930 +0,0 @@
-/*
- * 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.
- */
-#include <linux/module.h>
-#include <linux/mutex.h>
-#include <linux/types.h>
-#include <linux/jhash.h>
-#include <linux/list.h>
-#include <linux/rcupdate.h>
-#include <linux/marker.h>
-#include <linux/err.h>
-#include <linux/slab.h>
-
-extern struct marker __start___markers[];
-extern struct marker __stop___markers[];
-
-/* 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);
-
-/*
- * 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;
- /* 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;
- unsigned char ptype:1;
- unsigned char format_allocated:1;
- char name[0]; /* Contains name'\0'format'\0' */
-};
-
-/**
- * __mark_empty_function - Empty probe callback
- * @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(void *probe_private, void *call_private,
- const char *fmt, va_list *args)
-{
-}
-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.
- */
- 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->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(multi[i].probe_private, call_private,
- mdata->format, &args);
- va_end(args);
- }
- }
- rcu_read_unlock_sched_notrace();
-}
-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;
-
- 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->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(multi[i].probe_private, call_private,
- mdata->format, &args);
- }
- 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 *name)
-{
- struct hlist_head *head;
- struct hlist_node *node;
- struct marker_entry *e;
- u32 hash = jhash(name, strlen(name), 0);
-
- head = &marker_table[hash & ((1 << MARKER_HASH_BITS)-1)];
- hlist_for_each_entry(e, node, head, hlist) {
- if (!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 *name, const char *format)
-{
- struct hlist_head *head;
- struct hlist_node *node;
- struct marker_entry *e;
- size_t name_len = strlen(name) + 1;
- size_t format_len = 0;
- u32 hash = 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(name, e->name)) {
- printk(KERN_NOTICE
- "Marker %s busy\n", 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) + name_len + format_len,
- GFP_KERNEL);
- if (!e)
- return ERR_PTR(-ENOMEM);
- memcpy(&e->name[0], name, name_len);
- if (format) {
- e->format = &e->name[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(core_marker_format, "name %s format %s",
- 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 *name)
-{
- struct hlist_head *head;
- struct hlist_node *node;
- struct marker_entry *e;
- int found = 0;
- size_t len = strlen(name) + 1;
- u32 hash = jhash(name, len-1, 0);
-
- head = &marker_table[hash & ((1 << MARKER_HASH_BITS)-1)];
- hlist_for_each_entry(e, node, head, hlist) {
- if (!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);
- /* 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(core_marker_format, "name %s format %s",
- 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;
- /*
- * 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;
-
- if (elem->tp_name && (active ^ elem->state)) {
- WARN_ON(!elem->tp_cb);
- /*
- * It is ok to directly call the probe registration because type
- * checking has been done in the __trace_mark_tp() macro.
- */
-
- if (active) {
- /*
- * try_module_get should always succeed because we hold
- * lock_module() to get the tp_cb address.
- */
- ret = try_module_get(__module_text_address(
- (unsigned long)elem->tp_cb));
- BUG_ON(!ret);
- ret = tracepoint_probe_register_noupdate(
- elem->tp_name,
- elem->tp_cb);
- } else {
- ret = tracepoint_probe_unregister_noupdate(
- elem->tp_name,
- elem->tp_cb);
- /*
- * tracepoint_probe_update_all() must be called
- * before the module containing tp_cb is unloaded.
- */
- module_put(__module_text_address(
- (unsigned long)elem->tp_cb));
- }
- }
- elem->state = 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. */
- if (elem->tp_name && elem->state) {
- WARN_ON(!elem->tp_cb);
- /*
- * It is ok to directly call the probe registration because type
- * checking has been done in the __trace_mark_tp() macro.
- */
- ret = tracepoint_probe_unregister_noupdate(elem->tp_name,
- elem->tp_cb);
- WARN_ON(ret);
- /*
- * tracepoint_probe_update_all() must be called
- * before the module containing tp_cb is unloaded.
- */
- module_put(__module_text_address((unsigned long)elem->tp_cb));
- }
- elem->state = 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 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->name);
- if (mark_entry) {
- set_marker(mark_entry, iter, !!mark_entry->refcount);
- /*
- * ignore error, continue
- */
- } 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 */
- marker_update_probe_range(__start___markers, __stop___markers);
- /* Markers in modules. */
- module_update_markers();
- tracepoint_probe_update_all();
-}
-
-/**
- * marker_probe_register - Connect a probe to a marker
- * @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 *name, const char *format,
- marker_probe_func *probe, void *probe_private)
-{
- struct marker_entry *entry;
- int ret = 0;
- struct marker_probe_closure *old;
-
- mutex_lock(&markers_mutex);
- entry = get_marker(name);
- if (!entry) {
- entry = add_marker(name, format);
- if (IS_ERR(entry))
- ret = PTR_ERR(entry);
- } 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);
- goto end;
- }
- mutex_unlock(&markers_mutex);
- marker_update_probes();
- mutex_lock(&markers_mutex);
- entry = get_marker(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);
-end:
- mutex_unlock(&markers_mutex);
- return ret;
-}
-EXPORT_SYMBOL_GPL(marker_probe_register);
-
-/**
- * marker_probe_unregister - Disconnect a probe from a marker
- * @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 *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(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(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(name); /* Ignore busy error message */
- ret = 0;
-end:
- mutex_unlock(&markers_mutex);
- return ret;
-}
-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;
-
- 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);
- mutex_unlock(&markers_mutex);
- marker_update_probes();
- mutex_lock(&markers_mutex);
- entry = get_marker_from_private_data(probe, probe_private);
- 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(entry->name); /* Ignore busy error message */
-end:
- mutex_unlock(&markers_mutex);
- return ret;
-}
-EXPORT_SYMBOL_GPL(marker_probe_unregister_private_data);
-
-/**
- * marker_get_private_data - Get a marker's probe private data
- * @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 *name, marker_probe_func *probe,
- int num)
-{
- struct hlist_head *head;
- struct hlist_node *node;
- struct marker_entry *e;
- size_t name_len = strlen(name) + 1;
- u32 hash = jhash(name, name_len-1, 0);
- int i;
-
- head = &marker_table[hash & ((1 << MARKER_HASH_BITS)-1)];
- hlist_for_each_entry(e, node, head, hlist) {
- if (!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);
-}
-EXPORT_SYMBOL_GPL(marker_get_private_data);
-
-#ifdef CONFIG_MODULES
-
-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,
-};
-
-static int init_markers(void)
-{
- return register_module_notifier(&marker_module_nb);
-}
-__initcall(init_markers);
-
-#endif /* CONFIG_MODULES */
diff --git a/kernel/module.c b/kernel/module.c
index 05ce49c..b6ee424 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -2237,10 +2237,6 @@ static noinline struct module *load_module(void __user *umod,
sizeof(*mod->ctors), &mod->num_ctors);
#endif
-#ifdef CONFIG_MARKERS
- mod->markers = section_objs(hdr, sechdrs, secstrings, "__markers",
- sizeof(*mod->markers), &mod->num_markers);
-#endif
#ifdef CONFIG_TRACEPOINTS
mod->tracepoints = section_objs(hdr, sechdrs, secstrings,
"__tracepoints",
@@ -2958,20 +2954,6 @@ void module_layout(struct module *mod,
EXPORT_SYMBOL(module_layout);
#endif
-#ifdef CONFIG_MARKERS
-void module_update_markers(void)
-{
- struct module *mod;
-
- mutex_lock(&module_mutex);
- list_for_each_entry(mod, &modules, list)
- if (!mod->taints)
- marker_update_probe_range(mod->markers,
- mod->markers + mod->num_markers);
- mutex_unlock(&module_mutex);
-}
-#endif
-
#ifdef CONFIG_TRACEPOINTS
void module_update_tracepoints(void)
{
diff --git a/kernel/profile.c b/kernel/profile.c
index 419250e..a55d3a3 100644
--- a/kernel/profile.c
+++ b/kernel/profile.c
@@ -442,48 +442,51 @@ void profile_tick(int type)
#ifdef CONFIG_PROC_FS
#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
#include <asm/uaccess.h>
-static int prof_cpu_mask_read_proc(char *page, char **start, off_t off,
- int count, int *eof, void *data)
+static int prof_cpu_mask_proc_show(struct seq_file *m, void *v)
{
- int len = cpumask_scnprintf(page, count, data);
- if (count - len < 2)
- return -EINVAL;
- len += sprintf(page + len, "\n");
- return len;
+ seq_cpumask(m, prof_cpu_mask);
+ seq_putc(m, '\n');
+ return 0;
}
-static int prof_cpu_mask_write_proc(struct file *file,
- const char __user *buffer, unsigned long count, void *data)
+static int prof_cpu_mask_proc_open(struct inode *inode, struct file *file)
+{
+ return single_open(file, prof_cpu_mask_proc_show, NULL);
+}
+
+static ssize_t prof_cpu_mask_proc_write(struct file *file,
+ const char __user *buffer, size_t count, loff_t *pos)
{
- struct cpumask *mask = data;
- unsigned long full_count = count, err;
cpumask_var_t new_value;
+ int err;
if (!alloc_cpumask_var(&new_value, GFP_KERNEL))
return -ENOMEM;
err = cpumask_parse_user(buffer, count, new_value);
if (!err) {
- cpumask_copy(mask, new_value);
- err = full_count;
+ cpumask_copy(prof_cpu_mask, new_value);
+ err = count;
}
free_cpumask_var(new_value);
return err;
}
+static const struct file_operations prof_cpu_mask_proc_fops = {
+ .open = prof_cpu_mask_proc_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = single_release,
+ .write = prof_cpu_mask_proc_write,
+};
+
void create_prof_cpu_mask(struct proc_dir_entry *root_irq_dir)
{
- struct proc_dir_entry *entry;
-
/* create /proc/irq/prof_cpu_mask */
- entry = create_proc_entry("prof_cpu_mask", 0600, root_irq_dir);
- if (!entry)
- return;
- entry->data = prof_cpu_mask;
- entry->read_proc = prof_cpu_mask_read_proc;
- entry->write_proc = prof_cpu_mask_write_proc;
+ proc_create("prof_cpu_mask", 0600, root_irq_dir, &prof_cpu_mask_proc_fops);
}
/*
diff --git a/kernel/rcupdate.c b/kernel/rcupdate.c
index bd5d5c8..37ac454 100644
--- a/kernel/rcupdate.c
+++ b/kernel/rcupdate.c
@@ -19,7 +19,7 @@
*
* Authors: Dipankar Sarma <dipankar@in.ibm.com>
* Manfred Spraul <manfred@colorfullife.com>
- *
+ *
* Based on the original work by Paul McKenney <paulmck@us.ibm.com>
* and inputs from Rusty Russell, Andrea Arcangeli and Andi Kleen.
* Papers:
@@ -27,7 +27,7 @@
* http://lse.sourceforge.net/locking/rclock_OLS.2001.05.01c.sc.pdf (OLS2001)
*
* For detailed explanation of Read-Copy Update mechanism see -
- * http://lse.sourceforge.net/locking/rcupdate.html
+ * http://lse.sourceforge.net/locking/rcupdate.html
*
*/
#include <linux/types.h>
@@ -74,6 +74,8 @@ void wakeme_after_rcu(struct rcu_head *head)
complete(&rcu->completion);
}
+#ifdef CONFIG_TREE_PREEMPT_RCU
+
/**
* synchronize_rcu - wait until a grace period has elapsed.
*
@@ -87,7 +89,7 @@ void synchronize_rcu(void)
{
struct rcu_synchronize rcu;
- if (rcu_blocking_is_gp())
+ if (!rcu_scheduler_active)
return;
init_completion(&rcu.completion);
@@ -98,6 +100,46 @@ void synchronize_rcu(void)
}
EXPORT_SYMBOL_GPL(synchronize_rcu);
+#endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */
+
+/**
+ * synchronize_sched - wait until an rcu-sched grace period has elapsed.
+ *
+ * Control will return to the caller some time after a full rcu-sched
+ * grace period has elapsed, in other words after all currently executing
+ * rcu-sched read-side critical sections have completed. These read-side
+ * critical sections are delimited by rcu_read_lock_sched() and
+ * rcu_read_unlock_sched(), and may be nested. Note that preempt_disable(),
+ * local_irq_disable(), and so on may be used in place of
+ * rcu_read_lock_sched().
+ *
+ * This means that all preempt_disable code sequences, including NMI and
+ * hardware-interrupt handlers, in progress on entry will have completed
+ * before this primitive returns. However, this does not guarantee that
+ * softirq handlers will have completed, since in some kernels, these
+ * handlers can run in process context, and can block.
+ *
+ * This primitive provides the guarantees made by the (now removed)
+ * synchronize_kernel() API. In contrast, synchronize_rcu() only
+ * guarantees that rcu_read_lock() sections will have completed.
+ * In "classic RCU", these two guarantees happen to be one and
+ * the same, but can differ in realtime RCU implementations.
+ */
+void synchronize_sched(void)
+{
+ struct rcu_synchronize rcu;
+
+ if (rcu_blocking_is_gp())
+ return;
+
+ init_completion(&rcu.completion);
+ /* Will wake me after RCU finished. */
+ call_rcu_sched(&rcu.head, wakeme_after_rcu);
+ /* Wait for it. */
+ wait_for_completion(&rcu.completion);
+}
+EXPORT_SYMBOL_GPL(synchronize_sched);
+
/**
* synchronize_rcu_bh - wait until an rcu_bh grace period has elapsed.
*
diff --git a/kernel/rcutorture.c b/kernel/rcutorture.c
index b33db53..233768f 100644
--- a/kernel/rcutorture.c
+++ b/kernel/rcutorture.c
@@ -18,7 +18,7 @@
* Copyright (C) IBM Corporation, 2005, 2006
*
* Authors: Paul E. McKenney <paulmck@us.ibm.com>
- * Josh Triplett <josh@freedesktop.org>
+ * Josh Triplett <josh@freedesktop.org>
*
* See also: Documentation/RCU/torture.txt
*/
@@ -50,7 +50,7 @@
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Paul E. McKenney <paulmck@us.ibm.com> and "
- "Josh Triplett <josh@freedesktop.org>");
+ "Josh Triplett <josh@freedesktop.org>");
static int nreaders = -1; /* # reader threads, defaults to 2*ncpus */
static int nfakewriters = 4; /* # fake writer threads */
@@ -110,8 +110,8 @@ struct rcu_torture {
};
static LIST_HEAD(rcu_torture_freelist);
-static struct rcu_torture *rcu_torture_current = NULL;
-static long rcu_torture_current_version = 0;
+static struct rcu_torture *rcu_torture_current;
+static long rcu_torture_current_version;
static struct rcu_torture rcu_tortures[10 * RCU_TORTURE_PIPE_LEN];
static DEFINE_SPINLOCK(rcu_torture_lock);
static DEFINE_PER_CPU(long [RCU_TORTURE_PIPE_LEN + 1], rcu_torture_count) =
@@ -124,11 +124,11 @@ static atomic_t n_rcu_torture_alloc_fail;
static atomic_t n_rcu_torture_free;
static atomic_t n_rcu_torture_mberror;
static atomic_t n_rcu_torture_error;
-static long n_rcu_torture_timers = 0;
+static long n_rcu_torture_timers;
static struct list_head rcu_torture_removed;
static cpumask_var_t shuffle_tmp_mask;
-static int stutter_pause_test = 0;
+static int stutter_pause_test;
#if defined(MODULE) || defined(CONFIG_RCU_TORTURE_TEST_RUNNABLE)
#define RCUTORTURE_RUNNABLE_INIT 1
@@ -267,7 +267,8 @@ struct rcu_torture_ops {
int irq_capable;
char *name;
};
-static struct rcu_torture_ops *cur_ops = NULL;
+
+static struct rcu_torture_ops *cur_ops;
/*
* Definitions for rcu torture testing.
@@ -281,14 +282,17 @@ static int rcu_torture_read_lock(void) __acquires(RCU)
static void rcu_read_delay(struct rcu_random_state *rrsp)
{
- long delay;
- const long longdelay = 200;
+ const unsigned long shortdelay_us = 200;
+ const unsigned long longdelay_ms = 50;
- /* We want there to be long-running readers, but not all the time. */
+ /* We want a short delay sometimes to make a reader delay the grace
+ * period, and we want a long delay occasionally to trigger
+ * force_quiescent_state. */
- delay = rcu_random(rrsp) % (nrealreaders * 2 * longdelay);
- if (!delay)
- udelay(longdelay);
+ if (!(rcu_random(rrsp) % (nrealreaders * 2000 * longdelay_ms)))
+ mdelay(longdelay_ms);
+ if (!(rcu_random(rrsp) % (nrealreaders * 2 * shortdelay_us)))
+ udelay(shortdelay_us);
}
static void rcu_torture_read_unlock(int idx) __releases(RCU)
@@ -339,8 +343,8 @@ static struct rcu_torture_ops rcu_ops = {
.sync = synchronize_rcu,
.cb_barrier = rcu_barrier,
.stats = NULL,
- .irq_capable = 1,
- .name = "rcu"
+ .irq_capable = 1,
+ .name = "rcu"
};
static void rcu_sync_torture_deferred_free(struct rcu_torture *p)
@@ -638,7 +642,8 @@ rcu_torture_writer(void *arg)
do {
schedule_timeout_uninterruptible(1);
- if ((rp = rcu_torture_alloc()) == NULL)
+ rp = rcu_torture_alloc();
+ if (rp == NULL)
continue;
rp->rtort_pipe_count = 0;
udelay(rcu_random(&rand) & 0x3ff);
@@ -1110,7 +1115,7 @@ rcu_torture_init(void)
printk(KERN_ALERT "rcutorture: invalid torture type: \"%s\"\n",
torture_type);
mutex_unlock(&fullstop_mutex);
- return (-EINVAL);
+ return -EINVAL;
}
if (cur_ops->init)
cur_ops->init(); /* no "goto unwind" prior to this point!!! */
@@ -1161,7 +1166,7 @@ rcu_torture_init(void)
goto unwind;
}
fakewriter_tasks = kzalloc(nfakewriters * sizeof(fakewriter_tasks[0]),
- GFP_KERNEL);
+ GFP_KERNEL);
if (fakewriter_tasks == NULL) {
VERBOSE_PRINTK_ERRSTRING("out of memory");
firsterr = -ENOMEM;
@@ -1170,7 +1175,7 @@ rcu_torture_init(void)
for (i = 0; i < nfakewriters; i++) {
VERBOSE_PRINTK_STRING("Creating rcu_torture_fakewriter task");
fakewriter_tasks[i] = kthread_run(rcu_torture_fakewriter, NULL,
- "rcu_torture_fakewriter");
+ "rcu_torture_fakewriter");
if (IS_ERR(fakewriter_tasks[i])) {
firsterr = PTR_ERR(fakewriter_tasks[i]);
VERBOSE_PRINTK_ERRSTRING("Failed to create fakewriter");
diff --git a/kernel/rcutree.c b/kernel/rcutree.c
index 6b11b07..52b06f6 100644
--- a/kernel/rcutree.c
+++ b/kernel/rcutree.c
@@ -25,7 +25,7 @@
* and inputs from Rusty Russell, Andrea Arcangeli and Andi Kleen.
*
* For detailed explanation of Read-Copy Update mechanism see -
- * Documentation/RCU
+ * Documentation/RCU
*/
#include <linux/types.h>
#include <linux/kernel.h>
@@ -107,27 +107,23 @@ static void __cpuinit rcu_init_percpu_data(int cpu, struct rcu_state *rsp,
*/
void rcu_sched_qs(int cpu)
{
- unsigned long flags;
struct rcu_data *rdp;
- local_irq_save(flags);
rdp = &per_cpu(rcu_sched_data, cpu);
- rdp->passed_quiesc = 1;
rdp->passed_quiesc_completed = rdp->completed;
- rcu_preempt_qs(cpu);
- local_irq_restore(flags);
+ barrier();
+ rdp->passed_quiesc = 1;
+ rcu_preempt_note_context_switch(cpu);
}
void rcu_bh_qs(int cpu)
{
- unsigned long flags;
struct rcu_data *rdp;
- local_irq_save(flags);
rdp = &per_cpu(rcu_bh_data, cpu);
- rdp->passed_quiesc = 1;
rdp->passed_quiesc_completed = rdp->completed;
- local_irq_restore(flags);
+ barrier();
+ rdp->passed_quiesc = 1;
}
#ifdef CONFIG_NO_HZ
@@ -605,8 +601,6 @@ rcu_start_gp(struct rcu_state *rsp, unsigned long flags)
{
struct rcu_data *rdp = rsp->rda[smp_processor_id()];
struct rcu_node *rnp = rcu_get_root(rsp);
- struct rcu_node *rnp_cur;
- struct rcu_node *rnp_end;
if (!cpu_needs_another_gp(rsp, rdp)) {
spin_unlock_irqrestore(&rnp->lock, flags);
@@ -615,6 +609,7 @@ rcu_start_gp(struct rcu_state *rsp, unsigned long flags)
/* Advance to a new grace period and initialize state. */
rsp->gpnum++;
+ WARN_ON_ONCE(rsp->signaled == RCU_GP_INIT);
rsp->signaled = RCU_GP_INIT; /* Hold off force_quiescent_state. */
rsp->jiffies_force_qs = jiffies + RCU_JIFFIES_TILL_FORCE_QS;
record_gp_stall_check_time(rsp);
@@ -631,7 +626,9 @@ rcu_start_gp(struct rcu_state *rsp, unsigned long flags)
/* Special-case the common single-level case. */
if (NUM_RCU_NODES == 1) {
+ rcu_preempt_check_blocked_tasks(rnp);
rnp->qsmask = rnp->qsmaskinit;
+ rnp->gpnum = rsp->gpnum;
rsp->signaled = RCU_SIGNAL_INIT; /* force_quiescent_state OK. */
spin_unlock_irqrestore(&rnp->lock, flags);
return;
@@ -644,42 +641,28 @@ rcu_start_gp(struct rcu_state *rsp, unsigned long flags)
spin_lock(&rsp->onofflock); /* irqs already disabled. */
/*
- * Set the quiescent-state-needed bits in all the non-leaf RCU
- * nodes for all currently online CPUs. This operation relies
- * on the layout of the hierarchy within the rsp->node[] array.
- * Note that other CPUs will access only the leaves of the
- * hierarchy, which still indicate that no grace period is in
- * progress. In addition, we have excluded CPU-hotplug operations.
- *
- * We therefore do not need to hold any locks. Any required
- * memory barriers will be supplied by the locks guarding the
- * leaf rcu_nodes in the hierarchy.
- */
-
- rnp_end = rsp->level[NUM_RCU_LVLS - 1];
- for (rnp_cur = &rsp->node[0]; rnp_cur < rnp_end; rnp_cur++)
- rnp_cur->qsmask = rnp_cur->qsmaskinit;
-
- /*
- * Now set up the leaf nodes. Here we must be careful. First,
- * we need to hold the lock in order to exclude other CPUs, which
- * might be contending for the leaf nodes' locks. Second, as
- * soon as we initialize a given leaf node, its CPUs might run
- * up the rest of the hierarchy. We must therefore acquire locks
- * for each node that we touch during this stage. (But we still
- * are excluding CPU-hotplug operations.)
+ * Set the quiescent-state-needed bits in all the rcu_node
+ * structures for all currently online CPUs in breadth-first
+ * order, starting from the root rcu_node structure. This
+ * operation relies on the layout of the hierarchy within the
+ * rsp->node[] array. Note that other CPUs will access only
+ * the leaves of the hierarchy, which still indicate that no
+ * grace period is in progress, at least until the corresponding
+ * leaf node has been initialized. In addition, we have excluded
+ * CPU-hotplug operations.
*
* Note that the grace period cannot complete until we finish
* the initialization process, as there will be at least one
* qsmask bit set in the root node until that time, namely the
- * one corresponding to this CPU.
+ * one corresponding to this CPU, due to the fact that we have
+ * irqs disabled.
*/
- rnp_end = &rsp->node[NUM_RCU_NODES];
- rnp_cur = rsp->level[NUM_RCU_LVLS - 1];
- for (; rnp_cur < rnp_end; rnp_cur++) {
- spin_lock(&rnp_cur->lock); /* irqs already disabled. */
- rnp_cur->qsmask = rnp_cur->qsmaskinit;
- spin_unlock(&rnp_cur->lock); /* irqs already disabled. */
+ for (rnp = &rsp->node[0]; rnp < &rsp->node[NUM_RCU_NODES]; rnp++) {
+ spin_lock(&rnp->lock); /* irqs already disabled. */
+ rcu_preempt_check_blocked_tasks(rnp);
+ rnp->qsmask = rnp->qsmaskinit;
+ rnp->gpnum = rsp->gpnum;
+ spin_unlock(&rnp->lock); /* irqs already disabled. */
}
rsp->signaled = RCU_SIGNAL_INIT; /* force_quiescent_state now OK. */
@@ -722,6 +705,7 @@ rcu_process_gp_end(struct rcu_state *rsp, struct rcu_data *rdp)
static void cpu_quiet_msk_finish(struct rcu_state *rsp, unsigned long flags)
__releases(rnp->lock)
{
+ WARN_ON_ONCE(rsp->completed == rsp->gpnum);
rsp->completed = rsp->gpnum;
rcu_process_gp_end(rsp, rsp->rda[smp_processor_id()]);
rcu_start_gp(rsp, flags); /* releases root node's rnp->lock. */
@@ -739,6 +723,8 @@ cpu_quiet_msk(unsigned long mask, struct rcu_state *rsp, struct rcu_node *rnp,
unsigned long flags)
__releases(rnp->lock)
{
+ struct rcu_node *rnp_c;
+
/* Walk up the rcu_node hierarchy. */
for (;;) {
if (!(rnp->qsmask & mask)) {
@@ -762,8 +748,10 @@ cpu_quiet_msk(unsigned long mask, struct rcu_state *rsp, struct rcu_node *rnp,
break;
}
spin_unlock_irqrestore(&rnp->lock, flags);
+ rnp_c = rnp;
rnp = rnp->parent;
spin_lock_irqsave(&rnp->lock, flags);
+ WARN_ON_ONCE(rnp_c->qsmask);
}
/*
@@ -776,10 +764,10 @@ cpu_quiet_msk(unsigned long mask, struct rcu_state *rsp, struct rcu_node *rnp,
/*
* Record a quiescent state for the specified CPU, which must either be
- * the current CPU or an offline CPU. The lastcomp argument is used to
- * make sure we are still in the grace period of interest. We don't want
- * to end the current grace period based on quiescent states detected in
- * an earlier grace period!
+ * the current CPU. The lastcomp argument is used to make sure we are
+ * still in the grace period of interest. We don't want to end the current
+ * grace period based on quiescent states detected in an earlier grace
+ * period!
*/
static void
cpu_quiet(int cpu, struct rcu_state *rsp, struct rcu_data *rdp, long lastcomp)
@@ -814,7 +802,6 @@ cpu_quiet(int cpu, struct rcu_state *rsp, struct rcu_data *rdp, long lastcomp)
* This GP can't end until cpu checks in, so all of our
* callbacks can be processed during the next GP.
*/
- rdp = rsp->rda[smp_processor_id()];
rdp->nxttail[RCU_NEXT_READY_TAIL] = rdp->nxttail[RCU_NEXT_TAIL];
cpu_quiet_msk(mask, rsp, rnp, flags); /* releases rnp->lock */
@@ -872,7 +859,7 @@ static void __rcu_offline_cpu(int cpu, struct rcu_state *rsp)
spin_lock_irqsave(&rsp->onofflock, flags);
/* Remove the outgoing CPU from the masks in the rcu_node hierarchy. */
- rnp = rdp->mynode;
+ rnp = rdp->mynode; /* this is the outgoing CPU's rnp. */
mask = rdp->grpmask; /* rnp->grplo is constant. */
do {
spin_lock(&rnp->lock); /* irqs already disabled. */
@@ -881,7 +868,7 @@ static void __rcu_offline_cpu(int cpu, struct rcu_state *rsp)
spin_unlock(&rnp->lock); /* irqs remain disabled. */
break;
}
- rcu_preempt_offline_tasks(rsp, rnp);
+ rcu_preempt_offline_tasks(rsp, rnp, rdp);
mask = rnp->grpmask;
spin_unlock(&rnp->lock); /* irqs remain disabled. */
rnp = rnp->parent;
@@ -890,9 +877,6 @@ static void __rcu_offline_cpu(int cpu, struct rcu_state *rsp)
spin_unlock(&rsp->onofflock); /* irqs remain disabled. */
- /* Being offline is a quiescent state, so go record it. */
- cpu_quiet(cpu, rsp, rdp, lastcomp);
-
/*
* Move callbacks from the outgoing CPU to the running CPU.
* Note that the outgoing CPU is now quiscent, so it is now
@@ -1457,20 +1441,7 @@ rcu_init_percpu_data(int cpu, struct rcu_state *rsp, int preemptable)
rnp = rnp->parent;
} while (rnp != NULL && !(rnp->qsmaskinit & mask));
- spin_unlock(&rsp->onofflock); /* irqs remain disabled. */
-
- /*
- * A new grace period might start here. If so, we will be part of
- * it, and its gpnum will be greater than ours, so we will
- * participate. It is also possible for the gpnum to have been
- * incremented before this function was called, and the bitmasks
- * to not be filled out until now, in which case we will also
- * participate due to our gpnum being behind.
- */
-
- /* Since it is coming online, the CPU is in a quiescent state. */
- cpu_quiet(cpu, rsp, rdp, lastcomp);
- local_irq_restore(flags);
+ spin_unlock_irqrestore(&rsp->onofflock, flags);
}
static void __cpuinit rcu_online_cpu(int cpu)
diff --git a/kernel/rcutree.h b/kernel/rcutree.h
index bf8a6f9..8e8287a 100644
--- a/kernel/rcutree.h
+++ b/kernel/rcutree.h
@@ -142,7 +142,7 @@ struct rcu_data {
*/
struct rcu_head *nxtlist;
struct rcu_head **nxttail[RCU_NEXT_SIZE];
- long qlen; /* # of queued callbacks */
+ long qlen; /* # of queued callbacks */
long blimit; /* Upper limit on a processed batch */
#ifdef CONFIG_NO_HZ
diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h
index 4778936..1cee04f 100644
--- a/kernel/rcutree_plugin.h
+++ b/kernel/rcutree_plugin.h
@@ -64,22 +64,31 @@ EXPORT_SYMBOL_GPL(rcu_batches_completed);
* not in a quiescent state. There might be any number of tasks blocked
* while in an RCU read-side critical section.
*/
-static void rcu_preempt_qs_record(int cpu)
+static void rcu_preempt_qs(int cpu)
{
struct rcu_data *rdp = &per_cpu(rcu_preempt_data, cpu);
- rdp->passed_quiesc = 1;
rdp->passed_quiesc_completed = rdp->completed;
+ barrier();
+ rdp->passed_quiesc = 1;
}
/*
- * We have entered the scheduler or are between softirqs in ksoftirqd.
- * If we are in an RCU read-side critical section, we need to reflect
- * that in the state of the rcu_node structure corresponding to this CPU.
- * Caller must disable hardirqs.
+ * We have entered the scheduler, and the current task might soon be
+ * context-switched away from. If this task is in an RCU read-side
+ * critical section, we will no longer be able to rely on the CPU to
+ * record that fact, so we enqueue the task on the appropriate entry
+ * of the blocked_tasks[] array. The task will dequeue itself when
+ * it exits the outermost enclosing RCU read-side critical section.
+ * Therefore, the current grace period cannot be permitted to complete
+ * until the blocked_tasks[] entry indexed by the low-order bit of
+ * rnp->gpnum empties.
+ *
+ * Caller must disable preemption.
*/
-static void rcu_preempt_qs(int cpu)
+static void rcu_preempt_note_context_switch(int cpu)
{
struct task_struct *t = current;
+ unsigned long flags;
int phase;
struct rcu_data *rdp;
struct rcu_node *rnp;
@@ -90,7 +99,7 @@ static void rcu_preempt_qs(int cpu)
/* Possibly blocking in an RCU read-side critical section. */
rdp = rcu_preempt_state.rda[cpu];
rnp = rdp->mynode;
- spin_lock(&rnp->lock);
+ spin_lock_irqsave(&rnp->lock, flags);
t->rcu_read_unlock_special |= RCU_READ_UNLOCK_BLOCKED;
t->rcu_blocked_node = rnp;
@@ -103,11 +112,15 @@ static void rcu_preempt_qs(int cpu)
* state for the current grace period), then as long
* as that task remains queued, the current grace period
* cannot end.
+ *
+ * But first, note that the current CPU must still be
+ * on line!
*/
- phase = !(rnp->qsmask & rdp->grpmask) ^ (rnp->gpnum & 0x1);
+ WARN_ON_ONCE((rdp->grpmask & rnp->qsmaskinit) == 0);
+ WARN_ON_ONCE(!list_empty(&t->rcu_node_entry));
+ phase = (rnp->gpnum + !(rnp->qsmask & rdp->grpmask)) & 0x1;
list_add(&t->rcu_node_entry, &rnp->blocked_tasks[phase]);
- smp_mb(); /* Ensure later ctxt swtch seen after above. */
- spin_unlock(&rnp->lock);
+ spin_unlock_irqrestore(&rnp->lock, flags);
}
/*
@@ -119,9 +132,10 @@ static void rcu_preempt_qs(int cpu)
* grace period, then the fact that the task has been enqueued
* means that we continue to block the current grace period.
*/
- rcu_preempt_qs_record(cpu);
- t->rcu_read_unlock_special &= ~(RCU_READ_UNLOCK_NEED_QS |
- RCU_READ_UNLOCK_GOT_QS);
+ rcu_preempt_qs(cpu);
+ local_irq_save(flags);
+ t->rcu_read_unlock_special &= ~RCU_READ_UNLOCK_NEED_QS;
+ local_irq_restore(flags);
}
/*
@@ -157,7 +171,7 @@ static void rcu_read_unlock_special(struct task_struct *t)
special = t->rcu_read_unlock_special;
if (special & RCU_READ_UNLOCK_NEED_QS) {
t->rcu_read_unlock_special &= ~RCU_READ_UNLOCK_NEED_QS;
- t->rcu_read_unlock_special |= RCU_READ_UNLOCK_GOT_QS;
+ rcu_preempt_qs(smp_processor_id());
}
/* Hardware IRQ handlers cannot block. */
@@ -177,10 +191,10 @@ static void rcu_read_unlock_special(struct task_struct *t)
*/
for (;;) {
rnp = t->rcu_blocked_node;
- spin_lock(&rnp->lock);
+ spin_lock(&rnp->lock); /* irqs already disabled. */
if (rnp == t->rcu_blocked_node)
break;
- spin_unlock(&rnp->lock);
+ spin_unlock(&rnp->lock); /* irqs remain disabled. */
}
empty = list_empty(&rnp->blocked_tasks[rnp->gpnum & 0x1]);
list_del_init(&t->rcu_node_entry);
@@ -194,9 +208,8 @@ static void rcu_read_unlock_special(struct task_struct *t)
*/
if (!empty && rnp->qsmask == 0 &&
list_empty(&rnp->blocked_tasks[rnp->gpnum & 0x1])) {
- t->rcu_read_unlock_special &=
- ~(RCU_READ_UNLOCK_NEED_QS |
- RCU_READ_UNLOCK_GOT_QS);
+ struct rcu_node *rnp_p;
+
if (rnp->parent == NULL) {
/* Only one rcu_node in the tree. */
cpu_quiet_msk_finish(&rcu_preempt_state, flags);
@@ -205,9 +218,10 @@ static void rcu_read_unlock_special(struct task_struct *t)
/* Report up the rest of the hierarchy. */
mask = rnp->grpmask;
spin_unlock_irqrestore(&rnp->lock, flags);
- rnp = rnp->parent;
- spin_lock_irqsave(&rnp->lock, flags);
- cpu_quiet_msk(mask, &rcu_preempt_state, rnp, flags);
+ rnp_p = rnp->parent;
+ spin_lock_irqsave(&rnp_p->lock, flags);
+ WARN_ON_ONCE(rnp->qsmask);
+ cpu_quiet_msk(mask, &rcu_preempt_state, rnp_p, flags);
return;
}
spin_unlock(&rnp->lock);
@@ -259,6 +273,19 @@ static void rcu_print_task_stall(struct rcu_node *rnp)
#endif /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */
/*
+ * Check that the list of blocked tasks for the newly completed grace
+ * period is in fact empty. It is a serious bug to complete a grace
+ * period that still has RCU readers blocked! This function must be
+ * invoked -before- updating this rnp's ->gpnum, and the rnp's ->lock
+ * must be held by the caller.
+ */
+static void rcu_preempt_check_blocked_tasks(struct rcu_node *rnp)
+{
+ WARN_ON_ONCE(!list_empty(&rnp->blocked_tasks[rnp->gpnum & 0x1]));
+ WARN_ON_ONCE(rnp->qsmask);
+}
+
+/*
* Check for preempted RCU readers for the specified rcu_node structure.
* If the caller needs a reliable answer, it must hold the rcu_node's
* >lock.
@@ -280,7 +307,8 @@ static int rcu_preempted_readers(struct rcu_node *rnp)
* The caller must hold rnp->lock with irqs disabled.
*/
static void rcu_preempt_offline_tasks(struct rcu_state *rsp,
- struct rcu_node *rnp)
+ struct rcu_node *rnp,
+ struct rcu_data *rdp)
{
int i;
struct list_head *lp;
@@ -292,6 +320,9 @@ static void rcu_preempt_offline_tasks(struct rcu_state *rsp,
WARN_ONCE(1, "Last CPU thought to be offlined?");
return; /* Shouldn't happen: at least one CPU online. */
}
+ WARN_ON_ONCE(rnp != rdp->mynode &&
+ (!list_empty(&rnp->blocked_tasks[0]) ||
+ !list_empty(&rnp->blocked_tasks[1])));
/*
* Move tasks up to root rcu_node. Rely on the fact that the
@@ -335,20 +366,12 @@ static void rcu_preempt_check_callbacks(int cpu)
struct task_struct *t = current;
if (t->rcu_read_lock_nesting == 0) {
- t->rcu_read_unlock_special &=
- ~(RCU_READ_UNLOCK_NEED_QS | RCU_READ_UNLOCK_GOT_QS);
- rcu_preempt_qs_record(cpu);
+ t->rcu_read_unlock_special &= ~RCU_READ_UNLOCK_NEED_QS;
+ rcu_preempt_qs(cpu);
return;
}
- if (per_cpu(rcu_preempt_data, cpu).qs_pending) {
- if (t->rcu_read_unlock_special & RCU_READ_UNLOCK_GOT_QS) {
- rcu_preempt_qs_record(cpu);
- t->rcu_read_unlock_special &= ~RCU_READ_UNLOCK_GOT_QS;
- } else if (!(t->rcu_read_unlock_special &
- RCU_READ_UNLOCK_NEED_QS)) {
- t->rcu_read_unlock_special |= RCU_READ_UNLOCK_NEED_QS;
- }
- }
+ if (per_cpu(rcu_preempt_data, cpu).qs_pending)
+ t->rcu_read_unlock_special |= RCU_READ_UNLOCK_NEED_QS;
}
/*
@@ -434,7 +457,7 @@ EXPORT_SYMBOL_GPL(rcu_batches_completed);
* Because preemptable RCU does not exist, we never have to check for
* CPUs being in quiescent states.
*/
-static void rcu_preempt_qs(int cpu)
+static void rcu_preempt_note_context_switch(int cpu)
{
}
@@ -451,6 +474,16 @@ static void rcu_print_task_stall(struct rcu_node *rnp)
#endif /* #ifdef CONFIG_RCU_CPU_STALL_DETECTOR */
/*
+ * Because there is no preemptable RCU, there can be no readers blocked,
+ * so there is no need to check for blocked tasks. So check only for
+ * bogus qsmask values.
+ */
+static void rcu_preempt_check_blocked_tasks(struct rcu_node *rnp)
+{
+ WARN_ON_ONCE(rnp->qsmask);
+}
+
+/*
* Because preemptable RCU does not exist, there are never any preempted
* RCU readers.
*/
@@ -466,7 +499,8 @@ static int rcu_preempted_readers(struct rcu_node *rnp)
* tasks that were blocked within RCU read-side critical sections.
*/
static void rcu_preempt_offline_tasks(struct rcu_state *rsp,
- struct rcu_node *rnp)
+ struct rcu_node *rnp,
+ struct rcu_data *rdp)
{
}
diff --git a/kernel/rcutree_trace.c b/kernel/rcutree_trace.c
index 0ea1bff..c89f5e9 100644
--- a/kernel/rcutree_trace.c
+++ b/kernel/rcutree_trace.c
@@ -20,7 +20,7 @@
* Papers: http://www.rdrop.com/users/paulmck/RCU
*
* For detailed explanation of Read-Copy Update mechanism see -
- * Documentation/RCU
+ * Documentation/RCU
*
*/
#include <linux/types.h>
diff --git a/kernel/sched.c b/kernel/sched.c
index 291c8d2..91843ba 100644
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -681,15 +681,9 @@ inline void update_rq_clock(struct rq *rq)
* This interface allows printk to be called with the runqueue lock
* held and know whether or not it is OK to wake up the klogd.
*/
-int runqueue_is_locked(void)
+int runqueue_is_locked(int cpu)
{
- int cpu = get_cpu();
- struct rq *rq = cpu_rq(cpu);
- int ret;
-
- ret = spin_is_locked(&rq->lock);
- put_cpu();
- return ret;
+ return spin_is_locked(&cpu_rq(cpu)->lock);
}
/*
@@ -6825,23 +6819,8 @@ SYSCALL_DEFINE2(sched_rr_get_interval, pid_t, pid,
if (retval)
goto out_unlock;
- /*
- * Time slice is 0 for SCHED_FIFO tasks and for SCHED_OTHER
- * tasks that are on an otherwise idle runqueue:
- */
- time_slice = 0;
- if (p->policy == SCHED_RR) {
- time_slice = DEF_TIMESLICE;
- } else if (p->policy != SCHED_FIFO) {
- struct sched_entity *se = &p->se;
- unsigned long flags;
- struct rq *rq;
+ time_slice = p->sched_class->get_rr_interval(p);
- rq = task_rq_lock(p, &flags);
- if (rq->cfs.load.weight)
- time_slice = NS_TO_JIFFIES(sched_slice(&rq->cfs, se));
- task_rq_unlock(rq, &flags);
- }
read_unlock(&tasklist_lock);
jiffies_to_timespec(time_slice, &t);
retval = copy_to_user(interval, &t, sizeof(t)) ? -EFAULT : 0;
@@ -9171,6 +9150,7 @@ void __init sched_init_smp(void)
cpumask_var_t non_isolated_cpus;
alloc_cpumask_var(&non_isolated_cpus, GFP_KERNEL);
+ alloc_cpumask_var(&fallback_doms, GFP_KERNEL);
#if defined(CONFIG_NUMA)
sched_group_nodes_bycpu = kzalloc(nr_cpu_ids * sizeof(void **),
@@ -9202,7 +9182,6 @@ void __init sched_init_smp(void)
sched_init_granularity();
free_cpumask_var(non_isolated_cpus);
- alloc_cpumask_var(&fallback_doms, GFP_KERNEL);
init_sched_rt_class();
}
#else
diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c
index 990b188..ecc637a 100644
--- a/kernel/sched_fair.c
+++ b/kernel/sched_fair.c
@@ -710,31 +710,28 @@ place_entity(struct cfs_rq *cfs_rq, struct sched_entity *se, int initial)
if (initial && sched_feat(START_DEBIT))
vruntime += sched_vslice(cfs_rq, se);
- if (!initial) {
- /* sleeps upto a single latency don't count. */
- if (sched_feat(FAIR_SLEEPERS)) {
- unsigned long thresh = sysctl_sched_latency;
+ /* sleeps up to a single latency don't count. */
+ if (!initial && sched_feat(FAIR_SLEEPERS)) {
+ unsigned long thresh = sysctl_sched_latency;
- /*
- * Convert the sleeper threshold into virtual time.
- * SCHED_IDLE is a special sub-class. We care about
- * fairness only relative to other SCHED_IDLE tasks,
- * all of which have the same weight.
- */
- if (sched_feat(NORMALIZED_SLEEPER) &&
- (!entity_is_task(se) ||
- task_of(se)->policy != SCHED_IDLE))
- thresh = calc_delta_fair(thresh, se);
+ /*
+ * Convert the sleeper threshold into virtual time.
+ * SCHED_IDLE is a special sub-class. We care about
+ * fairness only relative to other SCHED_IDLE tasks,
+ * all of which have the same weight.
+ */
+ if (sched_feat(NORMALIZED_SLEEPER) && (!entity_is_task(se) ||
+ task_of(se)->policy != SCHED_IDLE))
+ thresh = calc_delta_fair(thresh, se);
- /*
- * Halve their sleep time's effect, to allow
- * for a gentler effect of sleepers:
- */
- if (sched_feat(GENTLE_FAIR_SLEEPERS))
- thresh >>= 1;
+ /*
+ * Halve their sleep time's effect, to allow
+ * for a gentler effect of sleepers:
+ */
+ if (sched_feat(GENTLE_FAIR_SLEEPERS))
+ thresh >>= 1;
- vruntime -= thresh;
- }
+ vruntime -= thresh;
}
/* ensure we never gain time by being placed backwards. */
@@ -1343,7 +1340,8 @@ static int select_task_rq_fair(struct task_struct *p, int sd_flag, int wake_flag
int sync = wake_flags & WF_SYNC;
if (sd_flag & SD_BALANCE_WAKE) {
- if (sched_feat(AFFINE_WAKEUPS))
+ if (sched_feat(AFFINE_WAKEUPS) &&
+ cpumask_test_cpu(cpu, &p->cpus_allowed))
want_affine = 1;
new_cpu = prev_cpu;
}
@@ -1941,6 +1939,25 @@ static void moved_group_fair(struct task_struct *p)
}
#endif
+unsigned int get_rr_interval_fair(struct task_struct *task)
+{
+ struct sched_entity *se = &task->se;
+ unsigned long flags;
+ struct rq *rq;
+ unsigned int rr_interval = 0;
+
+ /*
+ * Time slice is 0 for SCHED_OTHER tasks that are on an otherwise
+ * idle runqueue:
+ */
+ rq = task_rq_lock(task, &flags);
+ if (rq->cfs.load.weight)
+ rr_interval = NS_TO_JIFFIES(sched_slice(&rq->cfs, se));
+ task_rq_unlock(rq, &flags);
+
+ return rr_interval;
+}
+
/*
* All the scheduling class methods:
*/
@@ -1969,6 +1986,8 @@ static const struct sched_class fair_sched_class = {
.prio_changed = prio_changed_fair,
.switched_to = switched_to_fair,
+ .get_rr_interval = get_rr_interval_fair,
+
#ifdef CONFIG_FAIR_GROUP_SCHED
.moved_group = moved_group_fair,
#endif
diff --git a/kernel/sched_idletask.c b/kernel/sched_idletask.c
index a8b448a..b133a28 100644
--- a/kernel/sched_idletask.c
+++ b/kernel/sched_idletask.c
@@ -97,6 +97,11 @@ static void prio_changed_idle(struct rq *rq, struct task_struct *p,
check_preempt_curr(rq, p, 0);
}
+unsigned int get_rr_interval_idle(struct task_struct *task)
+{
+ return 0;
+}
+
/*
* Simple, special scheduling class for the per-CPU idle tasks:
*/
@@ -122,6 +127,8 @@ static const struct sched_class idle_sched_class = {
.set_curr_task = set_curr_task_idle,
.task_tick = task_tick_idle,
+ .get_rr_interval = get_rr_interval_idle,
+
.prio_changed = prio_changed_idle,
.switched_to = switched_to_idle,
diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c
index 13de712..a4d790c 100644
--- a/kernel/sched_rt.c
+++ b/kernel/sched_rt.c
@@ -1734,6 +1734,17 @@ static void set_curr_task_rt(struct rq *rq)
dequeue_pushable_task(rq, p);
}
+unsigned int get_rr_interval_rt(struct task_struct *task)
+{
+ /*
+ * Time slice is 0 for SCHED_FIFO tasks
+ */
+ if (task->policy == SCHED_RR)
+ return DEF_TIMESLICE;
+ else
+ return 0;
+}
+
static const struct sched_class rt_sched_class = {
.next = &fair_sched_class,
.enqueue_task = enqueue_task_rt,
@@ -1762,6 +1773,8 @@ static const struct sched_class rt_sched_class = {
.set_curr_task = set_curr_task_rt,
.task_tick = task_tick_rt,
+ .get_rr_interval = get_rr_interval_rt,
+
.prio_changed = prio_changed_rt,
.switched_to = switched_to_rt,
};
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index cc615f8..c71e91b 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -2414,11 +2414,9 @@ unsigned long ftrace_graph_funcs[FTRACE_GRAPH_MAX_FUNCS] __read_mostly;
static void *
__g_next(struct seq_file *m, loff_t *pos)
{
- unsigned long *array = m->private;
-
if (*pos >= ftrace_graph_count)
return NULL;
- return &array[*pos];
+ return &ftrace_graph_funcs[*pos];
}
static void *
@@ -2482,16 +2480,10 @@ ftrace_graph_open(struct inode *inode, struct file *file)
ftrace_graph_count = 0;
memset(ftrace_graph_funcs, 0, sizeof(ftrace_graph_funcs));
}
+ mutex_unlock(&graph_lock);
- if (file->f_mode & FMODE_READ) {
+ if (file->f_mode & FMODE_READ)
ret = seq_open(file, &ftrace_graph_seq_ops);
- if (!ret) {
- struct seq_file *m = file->private_data;
- m->private = ftrace_graph_funcs;
- }
- } else
- file->private_data = ftrace_graph_funcs;
- mutex_unlock(&graph_lock);
return ret;
}
@@ -2560,7 +2552,6 @@ ftrace_graph_write(struct file *file, const char __user *ubuf,
size_t cnt, loff_t *ppos)
{
struct trace_parser parser;
- unsigned long *array;
size_t read = 0;
ssize_t ret;
@@ -2574,12 +2565,6 @@ ftrace_graph_write(struct file *file, const char __user *ubuf,
goto out;
}
- if (file->f_mode & FMODE_READ) {
- struct seq_file *m = file->private_data;
- array = m->private;
- } else
- array = file->private_data;
-
if (trace_parser_get_init(&parser, FTRACE_BUFF_MAX)) {
ret = -ENOMEM;
goto out;
@@ -2591,7 +2576,7 @@ ftrace_graph_write(struct file *file, const char __user *ubuf,
parser.buffer[parser.idx] = 0;
/* we allow only one expression at a time */
- ret = ftrace_set_func(array, &ftrace_graph_count,
+ ret = ftrace_set_func(ftrace_graph_funcs, &ftrace_graph_count,
parser.buffer);
if (ret)
goto out;
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index fd52a19..a35925d 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -125,13 +125,13 @@ int ftrace_dump_on_oops;
static int tracing_set_tracer(const char *buf);
-#define BOOTUP_TRACER_SIZE 100
-static char bootup_tracer_buf[BOOTUP_TRACER_SIZE] __initdata;
+#define MAX_TRACER_SIZE 100
+static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata;
static char *default_bootup_tracer;
static int __init set_ftrace(char *str)
{
- strncpy(bootup_tracer_buf, str, BOOTUP_TRACER_SIZE);
+ strncpy(bootup_tracer_buf, str, MAX_TRACER_SIZE);
default_bootup_tracer = bootup_tracer_buf;
/* We are using ftrace early, expand it */
ring_buffer_expanded = 1;
@@ -242,13 +242,6 @@ static struct tracer *trace_types __read_mostly;
static struct tracer *current_trace __read_mostly;
/*
- * max_tracer_type_len is used to simplify the allocating of
- * buffers to read userspace tracer names. We keep track of
- * the longest tracer name registered.
- */
-static int max_tracer_type_len;
-
-/*
* trace_types_lock is used to protect the trace_types list.
* This lock is also used to keep user access serialized.
* Accesses from userspace will grab this lock while userspace
@@ -275,12 +268,18 @@ static DEFINE_SPINLOCK(tracing_start_lock);
*/
void trace_wake_up(void)
{
+ int cpu;
+
+ if (trace_flags & TRACE_ITER_BLOCK)
+ return;
/*
* The runqueue_is_locked() can fail, but this is the best we
* have for now:
*/
- if (!(trace_flags & TRACE_ITER_BLOCK) && !runqueue_is_locked())
+ cpu = get_cpu();
+ if (!runqueue_is_locked(cpu))
wake_up(&trace_wait);
+ put_cpu();
}
static int __init set_buf_size(char *str)
@@ -619,7 +618,6 @@ __releases(kernel_lock)
__acquires(kernel_lock)
{
struct tracer *t;
- int len;
int ret = 0;
if (!type->name) {
@@ -627,6 +625,11 @@ __acquires(kernel_lock)
return -1;
}
+ if (strlen(type->name) > MAX_TRACER_SIZE) {
+ pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE);
+ return -1;
+ }
+
/*
* When this gets called we hold the BKL which means that
* preemption is disabled. Various trace selftests however
@@ -641,7 +644,7 @@ __acquires(kernel_lock)
for (t = trace_types; t; t = t->next) {
if (strcmp(type->name, t->name) == 0) {
/* already found */
- pr_info("Trace %s already registered\n",
+ pr_info("Tracer %s already registered\n",
type->name);
ret = -1;
goto out;
@@ -692,9 +695,6 @@ __acquires(kernel_lock)
type->next = trace_types;
trace_types = type;
- len = strlen(type->name);
- if (len > max_tracer_type_len)
- max_tracer_type_len = len;
out:
tracing_selftest_running = false;
@@ -703,7 +703,7 @@ __acquires(kernel_lock)
if (ret || !default_bootup_tracer)
goto out_unlock;
- if (strncmp(default_bootup_tracer, type->name, BOOTUP_TRACER_SIZE))
+ if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE))
goto out_unlock;
printk(KERN_INFO "Starting tracer '%s'\n", type->name);
@@ -725,14 +725,13 @@ __acquires(kernel_lock)
void unregister_tracer(struct tracer *type)
{
struct tracer **t;
- int len;
mutex_lock(&trace_types_lock);
for (t = &trace_types; *t; t = &(*t)->next) {
if (*t == type)
goto found;
}
- pr_info("Trace %s not registered\n", type->name);
+ pr_info("Tracer %s not registered\n", type->name);
goto out;
found:
@@ -745,17 +744,7 @@ void unregister_tracer(struct tracer *type)
current_trace->stop(&global_trace);
current_trace = &nop_trace;
}
-
- if (strlen(type->name) != max_tracer_type_len)
- goto out;
-
- max_tracer_type_len = 0;
- for (t = &trace_types; *t; t = &(*t)->next) {
- len = strlen((*t)->name);
- if (len > max_tracer_type_len)
- max_tracer_type_len = len;
- }
- out:
+out:
mutex_unlock(&trace_types_lock);
}
@@ -2604,7 +2593,7 @@ static ssize_t
tracing_set_trace_read(struct file *filp, char __user *ubuf,
size_t cnt, loff_t *ppos)
{
- char buf[max_tracer_type_len+2];
+ char buf[MAX_TRACER_SIZE+2];
int r;
mutex_lock(&trace_types_lock);
@@ -2754,15 +2743,15 @@ static ssize_t
tracing_set_trace_write(struct file *filp, const char __user *ubuf,
size_t cnt, loff_t *ppos)
{
- char buf[max_tracer_type_len+1];
+ char buf[MAX_TRACER_SIZE+1];
int i;
size_t ret;
int err;
ret = cnt;
- if (cnt > max_tracer_type_len)
- cnt = max_tracer_type_len;
+ if (cnt > MAX_TRACER_SIZE)
+ cnt = MAX_TRACER_SIZE;
if (copy_from_user(&buf, ubuf, cnt))
return -EFAULT;
diff --git a/kernel/trace/trace_event_profile.c b/kernel/trace/trace_event_profile.c
index 55a25c9..dd44b87 100644
--- a/kernel/trace/trace_event_profile.c
+++ b/kernel/trace/trace_event_profile.c
@@ -8,6 +8,57 @@
#include <linux/module.h>
#include "trace.h"
+/*
+ * We can't use a size but a type in alloc_percpu()
+ * So let's create a dummy type that matches the desired size
+ */
+typedef struct {char buf[FTRACE_MAX_PROFILE_SIZE];} profile_buf_t;
+
+char *trace_profile_buf;
+EXPORT_SYMBOL_GPL(trace_profile_buf);
+
+char *trace_profile_buf_nmi;
+EXPORT_SYMBOL_GPL(trace_profile_buf_nmi);
+
+/* Count the events in use (per event id, not per instance) */
+static int total_profile_count;
+
+static int ftrace_profile_enable_event(struct ftrace_event_call *event)
+{
+ char *buf;
+ int ret = -ENOMEM;
+
+ if (atomic_inc_return(&event->profile_count))
+ return 0;
+
+ if (!total_profile_count++) {
+ buf = (char *)alloc_percpu(profile_buf_t);
+ if (!buf)
+ goto fail_buf;
+
+ rcu_assign_pointer(trace_profile_buf, buf);
+
+ buf = (char *)alloc_percpu(profile_buf_t);
+ if (!buf)
+ goto fail_buf_nmi;
+
+ rcu_assign_pointer(trace_profile_buf_nmi, buf);
+ }
+
+ ret = event->profile_enable();
+ if (!ret)
+ return 0;
+
+ kfree(trace_profile_buf_nmi);
+fail_buf_nmi:
+ kfree(trace_profile_buf);
+fail_buf:
+ total_profile_count--;
+ atomic_dec(&event->profile_count);
+
+ return ret;
+}
+
int ftrace_profile_enable(int event_id)
{
struct ftrace_event_call *event;
@@ -17,7 +68,7 @@ int ftrace_profile_enable(int event_id)
list_for_each_entry(event, &ftrace_events, list) {
if (event->id == event_id && event->profile_enable &&
try_module_get(event->mod)) {
- ret = event->profile_enable(event);
+ ret = ftrace_profile_enable_event(event);
break;
}
}
@@ -26,6 +77,33 @@ int ftrace_profile_enable(int event_id)
return ret;
}
+static void ftrace_profile_disable_event(struct ftrace_event_call *event)
+{
+ char *buf, *nmi_buf;
+
+ if (!atomic_add_negative(-1, &event->profile_count))
+ return;
+
+ event->profile_disable();
+
+ if (!--total_profile_count) {
+ buf = trace_profile_buf;
+ rcu_assign_pointer(trace_profile_buf, NULL);
+
+ nmi_buf = trace_profile_buf_nmi;
+ rcu_assign_pointer(trace_profile_buf_nmi, NULL);
+
+ /*
+ * Ensure every events in profiling have finished before
+ * releasing the buffers
+ */
+ synchronize_sched();
+
+ free_percpu(buf);
+ free_percpu(nmi_buf);
+ }
+}
+
void ftrace_profile_disable(int event_id)
{
struct ftrace_event_call *event;
@@ -33,7 +111,7 @@ void ftrace_profile_disable(int event_id)
mutex_lock(&event_mutex);
list_for_each_entry(event, &ftrace_events, list) {
if (event->id == event_id) {
- event->profile_disable(event);
+ ftrace_profile_disable_event(event);
module_put(event->mod);
break;
}
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 56c260b..6f03c8a 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -271,42 +271,32 @@ ftrace_event_write(struct file *file, const char __user *ubuf,
static void *
t_next(struct seq_file *m, void *v, loff_t *pos)
{
- struct list_head *list = m->private;
- struct ftrace_event_call *call;
+ struct ftrace_event_call *call = v;
(*pos)++;
- for (;;) {
- if (list == &ftrace_events)
- return NULL;
-
- call = list_entry(list, struct ftrace_event_call, list);
-
+ list_for_each_entry_continue(call, &ftrace_events, list) {
/*
* The ftrace subsystem is for showing formats only.
* They can not be enabled or disabled via the event files.
*/
if (call->regfunc)
- break;
-
- list = list->next;
+ return call;
}
- m->private = list->next;
-
- return call;
+ return NULL;
}
static void *t_start(struct seq_file *m, loff_t *pos)
{
- struct ftrace_event_call *call = NULL;
+ struct ftrace_event_call *call;
loff_t l;
mutex_lock(&event_mutex);
- m->private = ftrace_events.next;
+ call = list_entry(&ftrace_events, struct ftrace_event_call, list);
for (l = 0; l <= *pos; ) {
- call = t_next(m, NULL, &l);
+ call = t_next(m, call, &l);
if (!call)
break;
}
@@ -316,37 +306,28 @@ static void *t_start(struct seq_file *m, loff_t *pos)
static void *
s_next(struct seq_file *m, void *v, loff_t *pos)
{
- struct list_head *list = m->private;
- struct ftrace_event_call *call;
+ struct ftrace_event_call *call = v;
(*pos)++;
- retry:
- if (list == &ftrace_events)
- return NULL;
-
- call = list_entry(list, struct ftrace_event_call, list);
-
- if (!call->enabled) {
- list = list->next;
- goto retry;
+ list_for_each_entry_continue(call, &ftrace_events, list) {
+ if (call->enabled)
+ return call;
}
- m->private = list->next;
-
- return call;
+ return NULL;
}
static void *s_start(struct seq_file *m, loff_t *pos)
{
- struct ftrace_event_call *call = NULL;
+ struct ftrace_event_call *call;
loff_t l;
mutex_lock(&event_mutex);
- m->private = ftrace_events.next;
+ call = list_entry(&ftrace_events, struct ftrace_event_call, list);
for (l = 0; l <= *pos; ) {
- call = s_next(m, NULL, &l);
+ call = s_next(m, call, &l);
if (!call)
break;
}
diff --git a/kernel/trace/trace_printk.c b/kernel/trace/trace_printk.c
index 687699d..2547d88 100644
--- a/kernel/trace/trace_printk.c
+++ b/kernel/trace/trace_printk.c
@@ -11,7 +11,6 @@
#include <linux/ftrace.h>
#include <linux/string.h>
#include <linux/module.h>
-#include <linux/marker.h>
#include <linux/mutex.h>
#include <linux/ctype.h>
#include <linux/list.h>
diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index 233f348..9fbce6c 100644
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@ -384,10 +384,13 @@ static int sys_prof_refcount_exit;
static void prof_syscall_enter(struct pt_regs *regs, long id)
{
- struct syscall_trace_enter *rec;
struct syscall_metadata *sys_data;
+ struct syscall_trace_enter *rec;
+ unsigned long flags;
+ char *raw_data;
int syscall_nr;
int size;
+ int cpu;
syscall_nr = syscall_get_nr(current, regs);
if (!test_bit(syscall_nr, enabled_prof_enter_syscalls))
@@ -402,20 +405,38 @@ static void prof_syscall_enter(struct pt_regs *regs, long id)
size = ALIGN(size + sizeof(u32), sizeof(u64));
size -= sizeof(u32);
- do {
- char raw_data[size];
+ if (WARN_ONCE(size > FTRACE_MAX_PROFILE_SIZE,
+ "profile buffer not large enough"))
+ return;
+
+ /* Protect the per cpu buffer, begin the rcu read side */
+ local_irq_save(flags);
- /* zero the dead bytes from align to not leak stack to user */
- *(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL;
+ cpu = smp_processor_id();
+
+ if (in_nmi())
+ raw_data = rcu_dereference(trace_profile_buf_nmi);
+ else
+ raw_data = rcu_dereference(trace_profile_buf);
+
+ if (!raw_data)
+ goto end;
- rec = (struct syscall_trace_enter *) raw_data;
- tracing_generic_entry_update(&rec->ent, 0, 0);
- rec->ent.type = sys_data->enter_id;
- rec->nr = syscall_nr;
- syscall_get_arguments(current, regs, 0, sys_data->nb_args,
- (unsigned long *)&rec->args);
- perf_tp_event(sys_data->enter_id, 0, 1, rec, size);
- } while(0);
+ raw_data = per_cpu_ptr(raw_data, cpu);
+
+ /* zero the dead bytes from align to not leak stack to user */
+ *(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL;
+
+ rec = (struct syscall_trace_enter *) raw_data;
+ tracing_generic_entry_update(&rec->ent, 0, 0);
+ rec->ent.type = sys_data->enter_id;
+ rec->nr = syscall_nr;
+ syscall_get_arguments(current, regs, 0, sys_data->nb_args,
+ (unsigned long *)&rec->args);
+ perf_tp_event(sys_data->enter_id, 0, 1, rec, size);
+
+end:
+ local_irq_restore(flags);
}
int reg_prof_syscall_enter(char *name)
@@ -460,8 +481,12 @@ void unreg_prof_syscall_enter(char *name)
static void prof_syscall_exit(struct pt_regs *regs, long ret)
{
struct syscall_metadata *sys_data;
- struct syscall_trace_exit rec;
+ struct syscall_trace_exit *rec;
+ unsigned long flags;
int syscall_nr;
+ char *raw_data;
+ int size;
+ int cpu;
syscall_nr = syscall_get_nr(current, regs);
if (!test_bit(syscall_nr, enabled_prof_exit_syscalls))
@@ -471,12 +496,46 @@ static void prof_syscall_exit(struct pt_regs *regs, long ret)
if (!sys_data)
return;
- tracing_generic_entry_update(&rec.ent, 0, 0);
- rec.ent.type = sys_data->exit_id;
- rec.nr = syscall_nr;
- rec.ret = syscall_get_return_value(current, regs);
+ /* We can probably do that at build time */
+ size = ALIGN(sizeof(*rec) + sizeof(u32), sizeof(u64));
+ size -= sizeof(u32);
- perf_tp_event(sys_data->exit_id, 0, 1, &rec, sizeof(rec));
+ /*
+ * Impossible, but be paranoid with the future
+ * How to put this check outside runtime?
+ */
+ if (WARN_ONCE(size > FTRACE_MAX_PROFILE_SIZE,
+ "exit event has grown above profile buffer size"))
+ return;
+
+ /* Protect the per cpu buffer, begin the rcu read side */
+ local_irq_save(flags);
+ cpu = smp_processor_id();
+
+ if (in_nmi())
+ raw_data = rcu_dereference(trace_profile_buf_nmi);
+ else
+ raw_data = rcu_dereference(trace_profile_buf);
+
+ if (!raw_data)
+ goto end;
+
+ raw_data = per_cpu_ptr(raw_data, cpu);
+
+ /* zero the dead bytes from align to not leak stack to user */
+ *(u64 *)(&raw_data[size - sizeof(u64)]) = 0ULL;
+
+ rec = (struct syscall_trace_exit *)raw_data;
+
+ tracing_generic_entry_update(&rec->ent, 0, 0);
+ rec->ent.type = sys_data->exit_id;
+ rec->nr = syscall_nr;
+ rec->ret = syscall_get_return_value(current, regs);
+
+ perf_tp_event(sys_data->exit_id, 0, 1, rec, size);
+
+end:
+ local_irq_restore(flags);
}
int reg_prof_syscall_exit(char *name)
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