Update Linux to v5.10.109
Sourced from [1]
[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.10.109.tar.xz
Change-Id: I19bca9fc6762d4e63bcf3e4cba88bbe560d9c76c
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 2b55016..4a5d35d 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -62,8 +62,6 @@
})
/* hash bits for specific function selection */
-#define FTRACE_HASH_BITS 7
-#define FTRACE_FUNC_HASHSIZE (1 << FTRACE_HASH_BITS)
#define FTRACE_HASH_DEFAULT_BITS 10
#define FTRACE_HASH_MAX_BITS 12
@@ -104,7 +102,7 @@
tr = ops->private;
- return tr->function_pids != NULL;
+ return tr->function_pids != NULL || tr->function_no_pids != NULL;
}
static void ftrace_update_trampoline(struct ftrace_ops *ops);
@@ -145,24 +143,20 @@
struct ftrace_ops *op, struct pt_regs *regs)
{
struct trace_array *tr = op->private;
+ int pid;
- if (tr && this_cpu_read(tr->trace_buffer.data->ftrace_ignore_pid))
- return;
+ if (tr) {
+ pid = this_cpu_read(tr->array_buffer.data->ftrace_ignore_pid);
+ if (pid == FTRACE_PID_IGNORE)
+ return;
+ if (pid != FTRACE_PID_TRACE &&
+ pid != current->pid)
+ return;
+ }
op->saved_func(ip, parent_ip, op, regs);
}
-static void ftrace_sync(struct work_struct *work)
-{
- /*
- * This function is just a stub to implement a hard force
- * of synchronize_rcu(). This requires synchronizing
- * tasks even in userspace and idle.
- *
- * Yes, function tracing is rude.
- */
-}
-
static void ftrace_sync_ipi(void *data)
{
/* Probably not needed, but do it anyway */
@@ -236,7 +230,7 @@
/*
* For static tracing, we need to be a bit more careful.
* The function change takes affect immediately. Thus,
- * we need to coorditate the setting of the function_trace_ops
+ * we need to coordinate the setting of the function_trace_ops
* with the setting of the ftrace_trace_function.
*
* Set the function to the list ops, which will call the
@@ -248,7 +242,7 @@
* Make sure all CPUs see this. Yes this is slow, but static
* tracing is slow and nasty to have enabled.
*/
- schedule_on_each_cpu(ftrace_sync);
+ synchronize_rcu_tasks_rude();
/* Now all cpus are using the list ops. */
function_trace_op = set_function_trace_op;
/* Make sure the function_trace_op is visible on all CPUs */
@@ -326,6 +320,8 @@
if (ops->flags & FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED)
ops->flags |= FTRACE_OPS_FL_SAVE_REGS;
#endif
+ if (!ftrace_enabled && (ops->flags & FTRACE_OPS_FL_PERMANENT))
+ return -EBUSY;
if (!core_kernel_data((unsigned long)ops))
ops->flags |= FTRACE_OPS_FL_DYNAMIC;
@@ -463,10 +459,10 @@
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
/* function graph compares on total time */
-static int function_stat_cmp(void *p1, void *p2)
+static int function_stat_cmp(const void *p1, const void *p2)
{
- struct ftrace_profile *a = p1;
- struct ftrace_profile *b = p2;
+ const struct ftrace_profile *a = p1;
+ const struct ftrace_profile *b = p2;
if (a->time < b->time)
return -1;
@@ -477,10 +473,10 @@
}
#else
/* not function graph compares against hits */
-static int function_stat_cmp(void *p1, void *p2)
+static int function_stat_cmp(const void *p1, const void *p2)
{
- struct ftrace_profile *a = p1;
- struct ftrace_profile *b = p2;
+ const struct ftrace_profile *a = p1;
+ const struct ftrace_profile *b = p2;
if (a->counter < b->counter)
return -1;
@@ -1018,11 +1014,6 @@
# error Dynamic ftrace depends on MCOUNT_RECORD
#endif
-struct ftrace_func_entry {
- struct hlist_node hlist;
- unsigned long ip;
-};
-
struct ftrace_func_probe {
struct ftrace_probe_ops *probe_ops;
struct ftrace_ops ops;
@@ -1106,9 +1097,6 @@
#define ENTRY_SIZE sizeof(struct dyn_ftrace)
#define ENTRIES_PER_PAGE (PAGE_SIZE / ENTRY_SIZE)
-/* estimate from running different kernels */
-#define NR_TO_INIT 10000
-
static struct ftrace_page *ftrace_pages_start;
static struct ftrace_page *ftrace_pages;
@@ -1370,28 +1358,20 @@
static int ftrace_hash_ipmodify_update(struct ftrace_ops *ops,
struct ftrace_hash *new_hash);
-static struct ftrace_hash *
-__ftrace_hash_move(struct ftrace_hash *src)
+static struct ftrace_hash *dup_hash(struct ftrace_hash *src, int size)
{
struct ftrace_func_entry *entry;
- struct hlist_node *tn;
- struct hlist_head *hhd;
struct ftrace_hash *new_hash;
- int size = src->count;
+ struct hlist_head *hhd;
+ struct hlist_node *tn;
int bits = 0;
int i;
/*
- * If the new source is empty, just return the empty_hash.
+ * Use around half the size (max bit of it), but
+ * a minimum of 2 is fine (as size of 0 or 1 both give 1 for bits).
*/
- if (ftrace_hash_empty(src))
- return EMPTY_HASH;
-
- /*
- * Make the hash size about 1/2 the # found
- */
- for (size /= 2; size; size >>= 1)
- bits++;
+ bits = fls(size / 2);
/* Don't allocate too much */
if (bits > FTRACE_HASH_MAX_BITS)
@@ -1411,10 +1391,23 @@
__add_hash_entry(new_hash, entry);
}
}
-
return new_hash;
}
+static struct ftrace_hash *
+__ftrace_hash_move(struct ftrace_hash *src)
+{
+ int size = src->count;
+
+ /*
+ * If the new source is empty, just return the empty_hash.
+ */
+ if (ftrace_hash_empty(src))
+ return EMPTY_HASH;
+
+ return dup_hash(src, size);
+}
+
static int
ftrace_hash_move(struct ftrace_ops *ops, int enable,
struct ftrace_hash **dst, struct ftrace_hash *src)
@@ -1458,7 +1451,7 @@
{
/*
* The function record is a match if it exists in the filter
- * hash and not in the notrace hash. Note, an emty hash is
+ * hash and not in the notrace hash. Note, an empty hash is
* considered a match for the filter hash, but an empty
* notrace hash is considered not in the notrace hash.
*/
@@ -1534,6 +1527,28 @@
return 0;
}
+static struct dyn_ftrace *lookup_rec(unsigned long start, unsigned long end)
+{
+ struct ftrace_page *pg;
+ struct dyn_ftrace *rec = NULL;
+ struct dyn_ftrace key;
+
+ key.ip = start;
+ key.flags = end; /* overload flags, as it is unsigned long */
+
+ for (pg = ftrace_pages_start; pg; pg = pg->next) {
+ if (end < pg->records[0].ip ||
+ start >= (pg->records[pg->index - 1].ip + MCOUNT_INSN_SIZE))
+ continue;
+ rec = bsearch(&key, pg->records, pg->index,
+ sizeof(struct dyn_ftrace),
+ ftrace_cmp_recs);
+ if (rec)
+ break;
+ }
+ return rec;
+}
+
/**
* ftrace_location_range - return the first address of a traced location
* if it touches the given ip range
@@ -1548,23 +1563,11 @@
*/
unsigned long ftrace_location_range(unsigned long start, unsigned long end)
{
- struct ftrace_page *pg;
struct dyn_ftrace *rec;
- struct dyn_ftrace key;
- key.ip = start;
- key.flags = end; /* overload flags, as it is unsigned long */
-
- for (pg = ftrace_pages_start; pg; pg = pg->next) {
- if (end < pg->records[0].ip ||
- start >= (pg->records[pg->index - 1].ip + MCOUNT_INSN_SIZE))
- continue;
- rec = bsearch(&key, pg->records, pg->index,
- sizeof(struct dyn_ftrace),
- ftrace_cmp_recs);
- if (rec)
- return rec->ip;
- }
+ rec = lookup_rec(start, end);
+ if (rec)
+ return rec->ip;
return 0;
}
@@ -1717,6 +1720,9 @@
if (FTRACE_WARN_ON(ftrace_rec_count(rec) == FTRACE_REF_MAX))
return false;
+ if (ops->flags & FTRACE_OPS_FL_DIRECT)
+ rec->flags |= FTRACE_FL_DIRECT;
+
/*
* If there's only a single callback registered to a
* function, and the ops has a trampoline registered
@@ -1745,6 +1751,15 @@
rec->flags--;
/*
+ * Only the internal direct_ops should have the
+ * DIRECT flag set. Thus, if it is removing a
+ * function, then that function should no longer
+ * be direct.
+ */
+ if (ops->flags & FTRACE_OPS_FL_DIRECT)
+ rec->flags &= ~FTRACE_FL_DIRECT;
+
+ /*
* If the rec had REGS enabled and the ops that is
* being removed had REGS set, then see if there is
* still any ops for this record that wants regs.
@@ -1956,7 +1971,7 @@
char ins[MCOUNT_INSN_SIZE];
int i;
- if (probe_kernel_read(ins, p, MCOUNT_INSN_SIZE)) {
+ if (copy_from_kernel_nofault(ins, p, MCOUNT_INSN_SIZE)) {
printk(KERN_CONT "%s[FAULT] %px\n", fmt, p);
return;
}
@@ -2006,16 +2021,16 @@
{
unsigned long ip = rec ? rec->ip : 0;
+ pr_info("------------[ ftrace bug ]------------\n");
+
switch (failed) {
case -EFAULT:
- FTRACE_WARN_ON_ONCE(1);
pr_info("ftrace faulted on modifying ");
- print_ip_sym(ip);
+ print_ip_sym(KERN_INFO, ip);
break;
case -EINVAL:
- FTRACE_WARN_ON_ONCE(1);
pr_info("ftrace failed to modify ");
- print_ip_sym(ip);
+ print_ip_sym(KERN_INFO, ip);
print_ip_ins(" actual: ", (unsigned char *)ip);
pr_cont("\n");
if (ftrace_expected) {
@@ -2024,14 +2039,12 @@
}
break;
case -EPERM:
- FTRACE_WARN_ON_ONCE(1);
pr_info("ftrace faulted on writing ");
- print_ip_sym(ip);
+ print_ip_sym(KERN_INFO, ip);
break;
default:
- FTRACE_WARN_ON_ONCE(1);
pr_info("ftrace faulted on unknown error ");
- print_ip_sym(ip);
+ print_ip_sym(KERN_INFO, ip);
}
print_bug_type();
if (rec) {
@@ -2056,6 +2069,8 @@
ip = ftrace_get_addr_curr(rec);
pr_cont("\n expected tramp: %lx\n", ip);
}
+
+ FTRACE_WARN_ON_ONCE(1);
}
static int ftrace_check_record(struct dyn_ftrace *rec, bool enable, bool update)
@@ -2085,15 +2100,34 @@
* If enabling and the REGS flag does not match the REGS_EN, or
* the TRAMP flag doesn't match the TRAMP_EN, then do not ignore
* this record. Set flags to fail the compare against ENABLED.
+ * Same for direct calls.
*/
if (flag) {
- if (!(rec->flags & FTRACE_FL_REGS) !=
+ if (!(rec->flags & FTRACE_FL_REGS) !=
!(rec->flags & FTRACE_FL_REGS_EN))
flag |= FTRACE_FL_REGS;
- if (!(rec->flags & FTRACE_FL_TRAMP) !=
+ if (!(rec->flags & FTRACE_FL_TRAMP) !=
!(rec->flags & FTRACE_FL_TRAMP_EN))
flag |= FTRACE_FL_TRAMP;
+
+ /*
+ * Direct calls are special, as count matters.
+ * We must test the record for direct, if the
+ * DIRECT and DIRECT_EN do not match, but only
+ * if the count is 1. That's because, if the
+ * count is something other than one, we do not
+ * want the direct enabled (it will be done via the
+ * direct helper). But if DIRECT_EN is set, and
+ * the count is not one, we need to clear it.
+ */
+ if (ftrace_rec_count(rec) == 1) {
+ if (!(rec->flags & FTRACE_FL_DIRECT) !=
+ !(rec->flags & FTRACE_FL_DIRECT_EN))
+ flag |= FTRACE_FL_DIRECT;
+ } else if (rec->flags & FTRACE_FL_DIRECT_EN) {
+ flag |= FTRACE_FL_DIRECT;
+ }
}
/* If the state of this record hasn't changed, then do nothing */
@@ -2118,6 +2152,25 @@
else
rec->flags &= ~FTRACE_FL_TRAMP_EN;
}
+ if (flag & FTRACE_FL_DIRECT) {
+ /*
+ * If there's only one user (direct_ops helper)
+ * then we can call the direct function
+ * directly (no ftrace trampoline).
+ */
+ if (ftrace_rec_count(rec) == 1) {
+ if (rec->flags & FTRACE_FL_DIRECT)
+ rec->flags |= FTRACE_FL_DIRECT_EN;
+ else
+ rec->flags &= ~FTRACE_FL_DIRECT_EN;
+ } else {
+ /*
+ * Can only call directly if there's
+ * only one callback to the function.
+ */
+ rec->flags &= ~FTRACE_FL_DIRECT_EN;
+ }
+ }
}
/*
@@ -2147,7 +2200,7 @@
* and REGS states. The _EN flags must be disabled though.
*/
rec->flags &= ~(FTRACE_FL_ENABLED | FTRACE_FL_TRAMP_EN |
- FTRACE_FL_REGS_EN);
+ FTRACE_FL_REGS_EN | FTRACE_FL_DIRECT_EN);
}
ftrace_bug_type = FTRACE_BUG_NOP;
@@ -2230,7 +2283,7 @@
if (hash_contains_ip(ip, op->func_hash))
return op;
- }
+ }
return NULL;
}
@@ -2320,19 +2373,77 @@
return NULL;
}
+#ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
+/* Protected by rcu_tasks for reading, and direct_mutex for writing */
+static struct ftrace_hash *direct_functions = EMPTY_HASH;
+static DEFINE_MUTEX(direct_mutex);
+int ftrace_direct_func_count;
+
+/*
+ * Search the direct_functions hash to see if the given instruction pointer
+ * has a direct caller attached to it.
+ */
+unsigned long ftrace_find_rec_direct(unsigned long ip)
+{
+ struct ftrace_func_entry *entry;
+
+ entry = __ftrace_lookup_ip(direct_functions, ip);
+ if (!entry)
+ return 0;
+
+ return entry->direct;
+}
+
+static void call_direct_funcs(unsigned long ip, unsigned long pip,
+ struct ftrace_ops *ops, struct pt_regs *regs)
+{
+ unsigned long addr;
+
+ addr = ftrace_find_rec_direct(ip);
+ if (!addr)
+ return;
+
+ arch_ftrace_set_direct_caller(regs, addr);
+}
+
+struct ftrace_ops direct_ops = {
+ .func = call_direct_funcs,
+ .flags = FTRACE_OPS_FL_IPMODIFY | FTRACE_OPS_FL_RECURSION_SAFE
+ | FTRACE_OPS_FL_DIRECT | FTRACE_OPS_FL_SAVE_REGS
+ | FTRACE_OPS_FL_PERMANENT,
+ /*
+ * By declaring the main trampoline as this trampoline
+ * it will never have one allocated for it. Allocated
+ * trampolines should not call direct functions.
+ * The direct_ops should only be called by the builtin
+ * ftrace_regs_caller trampoline.
+ */
+ .trampoline = FTRACE_REGS_ADDR,
+};
+#endif /* CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS */
+
/**
* ftrace_get_addr_new - Get the call address to set to
* @rec: The ftrace record descriptor
*
* If the record has the FTRACE_FL_REGS set, that means that it
* wants to convert to a callback that saves all regs. If FTRACE_FL_REGS
- * is not not set, then it wants to convert to the normal callback.
+ * is not set, then it wants to convert to the normal callback.
*
* Returns the address of the trampoline to set to
*/
unsigned long ftrace_get_addr_new(struct dyn_ftrace *rec)
{
struct ftrace_ops *ops;
+ unsigned long addr;
+
+ if ((rec->flags & FTRACE_FL_DIRECT) &&
+ (ftrace_rec_count(rec) == 1)) {
+ addr = ftrace_find_rec_direct(rec->ip);
+ if (addr)
+ return addr;
+ WARN_ON_ONCE(1);
+ }
/* Trampolines take precedence over regs */
if (rec->flags & FTRACE_FL_TRAMP) {
@@ -2365,6 +2476,15 @@
unsigned long ftrace_get_addr_curr(struct dyn_ftrace *rec)
{
struct ftrace_ops *ops;
+ unsigned long addr;
+
+ /* Direct calls take precedence over trampolines */
+ if (rec->flags & FTRACE_FL_DIRECT_EN) {
+ addr = ftrace_find_rec_direct(rec->ip);
+ if (addr)
+ return addr;
+ WARN_ON_ONCE(1);
+ }
/* Trampolines take precedence over regs */
if (rec->flags & FTRACE_FL_TRAMP_EN) {
@@ -2520,14 +2640,14 @@
}
static int
-ftrace_code_disable(struct module *mod, struct dyn_ftrace *rec)
+ftrace_nop_initialize(struct module *mod, struct dyn_ftrace *rec)
{
int ret;
if (unlikely(ftrace_disabled))
return 0;
- ret = ftrace_make_nop(mod, rec, MCOUNT_ADDR);
+ ret = ftrace_init_nop(mod, rec);
if (ret) {
ftrace_bug_type = FTRACE_BUG_INIT;
ftrace_bug(ret, rec);
@@ -2675,6 +2795,51 @@
{
}
+/* List of trace_ops that have allocated trampolines */
+static LIST_HEAD(ftrace_ops_trampoline_list);
+
+static void ftrace_add_trampoline_to_kallsyms(struct ftrace_ops *ops)
+{
+ lockdep_assert_held(&ftrace_lock);
+ list_add_rcu(&ops->list, &ftrace_ops_trampoline_list);
+}
+
+static void ftrace_remove_trampoline_from_kallsyms(struct ftrace_ops *ops)
+{
+ lockdep_assert_held(&ftrace_lock);
+ list_del_rcu(&ops->list);
+ synchronize_rcu();
+}
+
+/*
+ * "__builtin__ftrace" is used as a module name in /proc/kallsyms for symbols
+ * for pages allocated for ftrace purposes, even though "__builtin__ftrace" is
+ * not a module.
+ */
+#define FTRACE_TRAMPOLINE_MOD "__builtin__ftrace"
+#define FTRACE_TRAMPOLINE_SYM "ftrace_trampoline"
+
+static void ftrace_trampoline_free(struct ftrace_ops *ops)
+{
+ if (ops && (ops->flags & FTRACE_OPS_FL_ALLOC_TRAMP) &&
+ ops->trampoline) {
+ /*
+ * Record the text poke event before the ksymbol unregister
+ * event.
+ */
+ perf_event_text_poke((void *)ops->trampoline,
+ (void *)ops->trampoline,
+ ops->trampoline_size, NULL, 0);
+ perf_event_ksymbol(PERF_RECORD_KSYMBOL_TYPE_OOL,
+ ops->trampoline, ops->trampoline_size,
+ true, FTRACE_TRAMPOLINE_SYM);
+ /* Remove from kallsyms after the perf events */
+ ftrace_remove_trampoline_from_kallsyms(ops);
+ }
+
+ arch_ftrace_trampoline_free(ops);
+}
+
static void ftrace_startup_enable(int command)
{
if (saved_ftrace_func != ftrace_trace_function) {
@@ -2724,6 +2889,8 @@
__unregister_ftrace_function(ops);
ftrace_start_up--;
ops->flags &= ~FTRACE_OPS_FL_ENABLED;
+ if (ops->flags & FTRACE_OPS_FL_DYNAMIC)
+ ftrace_trampoline_free(ops);
return ret;
}
@@ -2832,10 +2999,10 @@
* infrastructure to do the synchronization, thus we must do it
* ourselves.
*/
- schedule_on_each_cpu(ftrace_sync);
+ synchronize_rcu_tasks_rude();
/*
- * When the kernel is preeptive, tasks can be preempted
+ * When the kernel is preemptive, tasks can be preempted
* while on a ftrace trampoline. Just scheduling a task on
* a CPU is not good enough to flush them. Calling
* synchornize_rcu_tasks() will wait for those tasks to
@@ -2845,7 +3012,7 @@
synchronize_rcu_tasks();
free_ops:
- arch_ftrace_trampoline_free(ops);
+ ftrace_trampoline_free(ops);
}
return 0;
@@ -2887,6 +3054,8 @@
static u64 ftrace_update_time;
unsigned long ftrace_update_tot_cnt;
+unsigned long ftrace_number_of_pages;
+unsigned long ftrace_number_of_groups;
static inline int ops_traces_mod(struct ftrace_ops *ops)
{
@@ -2969,7 +3138,7 @@
* to the NOP instructions.
*/
if (!__is_defined(CC_USING_NOP_MCOUNT) &&
- !ftrace_code_disable(mod, p))
+ !ftrace_nop_initialize(mod, p))
break;
update_cnt++;
@@ -2986,18 +3155,20 @@
static int ftrace_allocate_records(struct ftrace_page *pg, int count)
{
int order;
+ int pages;
int cnt;
if (WARN_ON(!count))
return -EINVAL;
- order = get_count_order(DIV_ROUND_UP(count, ENTRIES_PER_PAGE));
+ pages = DIV_ROUND_UP(count, ENTRIES_PER_PAGE);
+ order = get_count_order(pages);
/*
* We want to fill as much as possible. No more than a page
* may be empty.
*/
- while ((PAGE_SIZE << order) / ENTRY_SIZE >= count + ENTRIES_PER_PAGE)
+ if (!is_power_of_2(pages))
order--;
again:
@@ -3011,6 +3182,9 @@
goto again;
}
+ ftrace_number_of_pages += 1 << order;
+ ftrace_number_of_groups++;
+
cnt = (PAGE_SIZE << order) / ENTRY_SIZE;
pg->size = cnt;
@@ -3062,10 +3236,13 @@
pg = start_pg;
while (pg) {
order = get_count_order(pg->size / ENTRIES_PER_PAGE);
- free_pages((unsigned long)pg->records, order);
+ if (order >= 0)
+ free_pages((unsigned long)pg->records, order);
start_pg = pg->next;
kfree(pg);
pg = start_pg;
+ ftrace_number_of_pages -= 1 << order;
+ ftrace_number_of_groups--;
}
pr_info("ftrace: FAILED to allocate memory for functions\n");
return NULL;
@@ -3476,10 +3653,11 @@
if (iter->flags & FTRACE_ITER_ENABLED) {
struct ftrace_ops *ops;
- seq_printf(m, " (%ld)%s%s",
+ seq_printf(m, " (%ld)%s%s%s",
ftrace_rec_count(rec),
rec->flags & FTRACE_FL_REGS ? " R" : " ",
- rec->flags & FTRACE_FL_IPMODIFY ? " I" : " ");
+ rec->flags & FTRACE_FL_IPMODIFY ? " I" : " ",
+ rec->flags & FTRACE_FL_DIRECT ? " D" : " ");
if (rec->flags & FTRACE_FL_TRAMP_EN) {
ops = ftrace_find_tramp_ops_any(rec);
if (ops) {
@@ -3495,7 +3673,14 @@
} else {
add_trampoline_func(m, NULL, rec);
}
- }
+ if (rec->flags & FTRACE_FL_DIRECT) {
+ unsigned long direct;
+
+ direct = ftrace_find_rec_direct(rec->ip);
+ if (direct)
+ seq_printf(m, "\n\tdirect-->%pS", (void *)direct);
+ }
+ }
seq_putc(m, '\n');
@@ -4212,7 +4397,7 @@
* @ip: The instruction pointer address to map @data to
* @data: The data to map to @ip
*
- * Returns 0 on succes otherwise an error.
+ * Returns 0 on success otherwise an error.
*/
int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper,
unsigned long ip, void *data)
@@ -4380,7 +4565,7 @@
/*
* Note, there's a small window here that the func_hash->filter_hash
- * may be NULL or empty. Need to be carefule when reading the loop.
+ * may be NULL or empty. Need to be careful when reading the loop.
*/
mutex_lock(&probe->ops.func_hash->regex_lock);
@@ -4826,6 +5011,400 @@
return ftrace_set_hash(ops, NULL, 0, ip, remove, reset, enable);
}
+#ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
+
+struct ftrace_direct_func {
+ struct list_head next;
+ unsigned long addr;
+ int count;
+};
+
+static LIST_HEAD(ftrace_direct_funcs);
+
+/**
+ * ftrace_find_direct_func - test an address if it is a registered direct caller
+ * @addr: The address of a registered direct caller
+ *
+ * This searches to see if a ftrace direct caller has been registered
+ * at a specific address, and if so, it returns a descriptor for it.
+ *
+ * This can be used by architecture code to see if an address is
+ * a direct caller (trampoline) attached to a fentry/mcount location.
+ * This is useful for the function_graph tracer, as it may need to
+ * do adjustments if it traced a location that also has a direct
+ * trampoline attached to it.
+ */
+struct ftrace_direct_func *ftrace_find_direct_func(unsigned long addr)
+{
+ struct ftrace_direct_func *entry;
+ bool found = false;
+
+ /* May be called by fgraph trampoline (protected by rcu tasks) */
+ list_for_each_entry_rcu(entry, &ftrace_direct_funcs, next) {
+ if (entry->addr == addr) {
+ found = true;
+ break;
+ }
+ }
+ if (found)
+ return entry;
+
+ return NULL;
+}
+
+static struct ftrace_direct_func *ftrace_alloc_direct_func(unsigned long addr)
+{
+ struct ftrace_direct_func *direct;
+
+ direct = kmalloc(sizeof(*direct), GFP_KERNEL);
+ if (!direct)
+ return NULL;
+ direct->addr = addr;
+ direct->count = 0;
+ list_add_rcu(&direct->next, &ftrace_direct_funcs);
+ ftrace_direct_func_count++;
+ return direct;
+}
+
+/**
+ * register_ftrace_direct - Call a custom trampoline directly
+ * @ip: The address of the nop at the beginning of a function
+ * @addr: The address of the trampoline to call at @ip
+ *
+ * This is used to connect a direct call from the nop location (@ip)
+ * at the start of ftrace traced functions. The location that it calls
+ * (@addr) must be able to handle a direct call, and save the parameters
+ * of the function being traced, and restore them (or inject new ones
+ * if needed), before returning.
+ *
+ * Returns:
+ * 0 on success
+ * -EBUSY - Another direct function is already attached (there can be only one)
+ * -ENODEV - @ip does not point to a ftrace nop location (or not supported)
+ * -ENOMEM - There was an allocation failure.
+ */
+int register_ftrace_direct(unsigned long ip, unsigned long addr)
+{
+ struct ftrace_direct_func *direct;
+ struct ftrace_func_entry *entry;
+ struct ftrace_hash *free_hash = NULL;
+ struct dyn_ftrace *rec;
+ int ret = -EBUSY;
+
+ mutex_lock(&direct_mutex);
+
+ /* See if there's a direct function at @ip already */
+ if (ftrace_find_rec_direct(ip))
+ goto out_unlock;
+
+ ret = -ENODEV;
+ rec = lookup_rec(ip, ip);
+ if (!rec)
+ goto out_unlock;
+
+ /*
+ * Check if the rec says it has a direct call but we didn't
+ * find one earlier?
+ */
+ if (WARN_ON(rec->flags & FTRACE_FL_DIRECT))
+ goto out_unlock;
+
+ /* Make sure the ip points to the exact record */
+ if (ip != rec->ip) {
+ ip = rec->ip;
+ /* Need to check this ip for a direct. */
+ if (ftrace_find_rec_direct(ip))
+ goto out_unlock;
+ }
+
+ ret = -ENOMEM;
+ if (ftrace_hash_empty(direct_functions) ||
+ direct_functions->count > 2 * (1 << direct_functions->size_bits)) {
+ struct ftrace_hash *new_hash;
+ int size = ftrace_hash_empty(direct_functions) ? 0 :
+ direct_functions->count + 1;
+
+ if (size < 32)
+ size = 32;
+
+ new_hash = dup_hash(direct_functions, size);
+ if (!new_hash)
+ goto out_unlock;
+
+ free_hash = direct_functions;
+ direct_functions = new_hash;
+ }
+
+ entry = kmalloc(sizeof(*entry), GFP_KERNEL);
+ if (!entry)
+ goto out_unlock;
+
+ direct = ftrace_find_direct_func(addr);
+ if (!direct) {
+ direct = ftrace_alloc_direct_func(addr);
+ if (!direct) {
+ kfree(entry);
+ goto out_unlock;
+ }
+ }
+
+ entry->ip = ip;
+ entry->direct = addr;
+ __add_hash_entry(direct_functions, entry);
+
+ ret = ftrace_set_filter_ip(&direct_ops, ip, 0, 0);
+ if (ret)
+ remove_hash_entry(direct_functions, entry);
+
+ if (!ret && !(direct_ops.flags & FTRACE_OPS_FL_ENABLED)) {
+ ret = register_ftrace_function(&direct_ops);
+ if (ret)
+ ftrace_set_filter_ip(&direct_ops, ip, 1, 0);
+ }
+
+ if (ret) {
+ kfree(entry);
+ if (!direct->count) {
+ list_del_rcu(&direct->next);
+ synchronize_rcu_tasks();
+ kfree(direct);
+ if (free_hash)
+ free_ftrace_hash(free_hash);
+ free_hash = NULL;
+ ftrace_direct_func_count--;
+ }
+ } else {
+ direct->count++;
+ }
+ out_unlock:
+ mutex_unlock(&direct_mutex);
+
+ if (free_hash) {
+ synchronize_rcu_tasks();
+ free_ftrace_hash(free_hash);
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(register_ftrace_direct);
+
+static struct ftrace_func_entry *find_direct_entry(unsigned long *ip,
+ struct dyn_ftrace **recp)
+{
+ struct ftrace_func_entry *entry;
+ struct dyn_ftrace *rec;
+
+ rec = lookup_rec(*ip, *ip);
+ if (!rec)
+ return NULL;
+
+ entry = __ftrace_lookup_ip(direct_functions, rec->ip);
+ if (!entry) {
+ WARN_ON(rec->flags & FTRACE_FL_DIRECT);
+ return NULL;
+ }
+
+ WARN_ON(!(rec->flags & FTRACE_FL_DIRECT));
+
+ /* Passed in ip just needs to be on the call site */
+ *ip = rec->ip;
+
+ if (recp)
+ *recp = rec;
+
+ return entry;
+}
+
+int unregister_ftrace_direct(unsigned long ip, unsigned long addr)
+{
+ struct ftrace_direct_func *direct;
+ struct ftrace_func_entry *entry;
+ int ret = -ENODEV;
+
+ mutex_lock(&direct_mutex);
+
+ entry = find_direct_entry(&ip, NULL);
+ if (!entry)
+ goto out_unlock;
+
+ if (direct_functions->count == 1)
+ unregister_ftrace_function(&direct_ops);
+
+ ret = ftrace_set_filter_ip(&direct_ops, ip, 1, 0);
+
+ WARN_ON(ret);
+
+ remove_hash_entry(direct_functions, entry);
+
+ direct = ftrace_find_direct_func(addr);
+ if (!WARN_ON(!direct)) {
+ /* This is the good path (see the ! before WARN) */
+ direct->count--;
+ WARN_ON(direct->count < 0);
+ if (!direct->count) {
+ list_del_rcu(&direct->next);
+ synchronize_rcu_tasks();
+ kfree(direct);
+ kfree(entry);
+ ftrace_direct_func_count--;
+ }
+ }
+ out_unlock:
+ mutex_unlock(&direct_mutex);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(unregister_ftrace_direct);
+
+static struct ftrace_ops stub_ops = {
+ .func = ftrace_stub,
+};
+
+/**
+ * ftrace_modify_direct_caller - modify ftrace nop directly
+ * @entry: The ftrace hash entry of the direct helper for @rec
+ * @rec: The record representing the function site to patch
+ * @old_addr: The location that the site at @rec->ip currently calls
+ * @new_addr: The location that the site at @rec->ip should call
+ *
+ * An architecture may overwrite this function to optimize the
+ * changing of the direct callback on an ftrace nop location.
+ * This is called with the ftrace_lock mutex held, and no other
+ * ftrace callbacks are on the associated record (@rec). Thus,
+ * it is safe to modify the ftrace record, where it should be
+ * currently calling @old_addr directly, to call @new_addr.
+ *
+ * Safety checks should be made to make sure that the code at
+ * @rec->ip is currently calling @old_addr. And this must
+ * also update entry->direct to @new_addr.
+ */
+int __weak ftrace_modify_direct_caller(struct ftrace_func_entry *entry,
+ struct dyn_ftrace *rec,
+ unsigned long old_addr,
+ unsigned long new_addr)
+{
+ unsigned long ip = rec->ip;
+ int ret;
+
+ /*
+ * The ftrace_lock was used to determine if the record
+ * had more than one registered user to it. If it did,
+ * we needed to prevent that from changing to do the quick
+ * switch. But if it did not (only a direct caller was attached)
+ * then this function is called. But this function can deal
+ * with attached callers to the rec that we care about, and
+ * since this function uses standard ftrace calls that take
+ * the ftrace_lock mutex, we need to release it.
+ */
+ mutex_unlock(&ftrace_lock);
+
+ /*
+ * By setting a stub function at the same address, we force
+ * the code to call the iterator and the direct_ops helper.
+ * This means that @ip does not call the direct call, and
+ * we can simply modify it.
+ */
+ ret = ftrace_set_filter_ip(&stub_ops, ip, 0, 0);
+ if (ret)
+ goto out_lock;
+
+ ret = register_ftrace_function(&stub_ops);
+ if (ret) {
+ ftrace_set_filter_ip(&stub_ops, ip, 1, 0);
+ goto out_lock;
+ }
+
+ entry->direct = new_addr;
+
+ /*
+ * By removing the stub, we put back the direct call, calling
+ * the @new_addr.
+ */
+ unregister_ftrace_function(&stub_ops);
+ ftrace_set_filter_ip(&stub_ops, ip, 1, 0);
+
+ out_lock:
+ mutex_lock(&ftrace_lock);
+
+ return ret;
+}
+
+/**
+ * modify_ftrace_direct - Modify an existing direct call to call something else
+ * @ip: The instruction pointer to modify
+ * @old_addr: The address that the current @ip calls directly
+ * @new_addr: The address that the @ip should call
+ *
+ * This modifies a ftrace direct caller at an instruction pointer without
+ * having to disable it first. The direct call will switch over to the
+ * @new_addr without missing anything.
+ *
+ * Returns: zero on success. Non zero on error, which includes:
+ * -ENODEV : the @ip given has no direct caller attached
+ * -EINVAL : the @old_addr does not match the current direct caller
+ */
+int modify_ftrace_direct(unsigned long ip,
+ unsigned long old_addr, unsigned long new_addr)
+{
+ struct ftrace_direct_func *direct, *new_direct = NULL;
+ struct ftrace_func_entry *entry;
+ struct dyn_ftrace *rec;
+ int ret = -ENODEV;
+
+ mutex_lock(&direct_mutex);
+
+ mutex_lock(&ftrace_lock);
+ entry = find_direct_entry(&ip, &rec);
+ if (!entry)
+ goto out_unlock;
+
+ ret = -EINVAL;
+ if (entry->direct != old_addr)
+ goto out_unlock;
+
+ direct = ftrace_find_direct_func(old_addr);
+ if (WARN_ON(!direct))
+ goto out_unlock;
+ if (direct->count > 1) {
+ ret = -ENOMEM;
+ new_direct = ftrace_alloc_direct_func(new_addr);
+ if (!new_direct)
+ goto out_unlock;
+ direct->count--;
+ new_direct->count++;
+ } else {
+ direct->addr = new_addr;
+ }
+
+ /*
+ * If there's no other ftrace callback on the rec->ip location,
+ * then it can be changed directly by the architecture.
+ * If there is another caller, then we just need to change the
+ * direct caller helper to point to @new_addr.
+ */
+ if (ftrace_rec_count(rec) == 1) {
+ ret = ftrace_modify_direct_caller(entry, rec, old_addr, new_addr);
+ } else {
+ entry->direct = new_addr;
+ ret = 0;
+ }
+
+ if (unlikely(ret && new_direct)) {
+ direct->count++;
+ list_del_rcu(&new_direct->next);
+ synchronize_rcu_tasks();
+ kfree(new_direct);
+ ftrace_direct_func_count--;
+ }
+
+ out_unlock:
+ mutex_unlock(&ftrace_lock);
+ mutex_unlock(&direct_mutex);
+ return ret;
+}
+EXPORT_SYMBOL_GPL(modify_ftrace_direct);
+#endif /* CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS */
+
/**
* ftrace_set_filter_ip - set a function to filter on in ftrace by address
* @ops - the ops to set the filter with
@@ -4996,7 +5575,7 @@
struct ftrace_hash *hash;
hash = alloc_ftrace_hash(FTRACE_HASH_DEFAULT_BITS);
- if (WARN_ON(!hash))
+ if (MEM_FAIL(!hash, "Failed to allocate hash\n"))
return;
while (buf) {
@@ -5415,7 +5994,7 @@
* infrastructure to do the synchronization, thus we must do it
* ourselves.
*/
- schedule_on_each_cpu(ftrace_sync);
+ synchronize_rcu_tasks_rude();
free_ftrace_hash(old_hash);
}
@@ -5716,6 +6295,27 @@
unsigned int num_funcs;
};
+static int ftrace_get_trampoline_kallsym(unsigned int symnum,
+ unsigned long *value, char *type,
+ char *name, char *module_name,
+ int *exported)
+{
+ struct ftrace_ops *op;
+
+ list_for_each_entry_rcu(op, &ftrace_ops_trampoline_list, list) {
+ if (!op->trampoline || symnum--)
+ continue;
+ *value = op->trampoline;
+ *type = 't';
+ strlcpy(name, FTRACE_TRAMPOLINE_SYM, KSYM_NAME_LEN);
+ strlcpy(module_name, FTRACE_TRAMPOLINE_MOD, MODULE_NAME_LEN);
+ *exported = 0;
+ return 0;
+ }
+
+ return -ERANGE;
+}
+
#ifdef CONFIG_MODULES
#define next_to_ftrace_page(p) container_of(p, struct ftrace_page, next)
@@ -5729,9 +6329,17 @@
for (ops = ftrace_ops_list; ops != &ftrace_list_end; ops = ops->next) {
if (ops_references_rec(ops, rec)) {
+ if (WARN_ON_ONCE(ops->flags & FTRACE_OPS_FL_DIRECT))
+ continue;
+ if (WARN_ON_ONCE(ops->flags & FTRACE_OPS_FL_IPMODIFY))
+ continue;
cnt++;
if (ops->flags & FTRACE_OPS_FL_SAVE_REGS)
rec->flags |= FTRACE_FL_REGS;
+ if (cnt == 1 && ops->trampoline)
+ rec->flags |= FTRACE_FL_TRAMP;
+ else
+ rec->flags &= ~FTRACE_FL_TRAMP;
}
}
@@ -5854,9 +6462,12 @@
clear_mod_from_hashes(pg);
order = get_count_order(pg->size / ENTRIES_PER_PAGE);
- free_pages((unsigned long)pg->records, order);
+ if (order >= 0)
+ free_pages((unsigned long)pg->records, order);
tmp_page = pg->next;
kfree(pg);
+ ftrace_number_of_pages -= 1 << order;
+ ftrace_number_of_groups--;
}
}
@@ -6053,6 +6664,7 @@
{
struct ftrace_mod_map *mod_map;
struct ftrace_mod_func *mod_func;
+ int ret;
preempt_disable();
list_for_each_entry_rcu(mod_map, &ftrace_mod_maps, list) {
@@ -6079,8 +6691,10 @@
WARN_ON(1);
break;
}
+ ret = ftrace_get_trampoline_kallsym(symnum, value, type, name,
+ module_name, exported);
preempt_enable();
- return -ERANGE;
+ return ret;
}
#else
@@ -6092,6 +6706,18 @@
{
return NULL;
}
+int ftrace_mod_get_kallsym(unsigned int symnum, unsigned long *value,
+ char *type, char *name, char *module_name,
+ int *exported)
+{
+ int ret;
+
+ preempt_disable();
+ ret = ftrace_get_trampoline_kallsym(symnum, value, type, name,
+ module_name, exported);
+ preempt_enable();
+ return ret;
+}
#endif /* CONFIG_MODULES */
struct ftrace_init_func {
@@ -6139,7 +6765,7 @@
func = kmalloc(sizeof(*func), GFP_KERNEL);
if (!func) {
- WARN_ONCE(1, "alloc failure, ftrace filter could be stale\n");
+ MEM_FAIL(1, "alloc failure, ftrace filter could be stale\n");
return;
}
@@ -6197,7 +6823,10 @@
if (!pg->index) {
*last_pg = pg->next;
order = get_count_order(pg->size / ENTRIES_PER_PAGE);
- free_pages((unsigned long)pg->records, order);
+ if (order >= 0)
+ free_pages((unsigned long)pg->records, order);
+ ftrace_number_of_pages -= 1 << order;
+ ftrace_number_of_groups--;
kfree(pg);
pg = container_of(last_pg, struct ftrace_page, next);
if (!(*last_pg))
@@ -6253,6 +6882,9 @@
__start_mcount_loc,
__stop_mcount_loc);
+ pr_info("ftrace: allocated %ld pages with %ld groups\n",
+ ftrace_number_of_pages, ftrace_number_of_groups);
+
set_ftrace_early_filters();
return;
@@ -6267,7 +6899,24 @@
static void ftrace_update_trampoline(struct ftrace_ops *ops)
{
+ unsigned long trampoline = ops->trampoline;
+
arch_ftrace_update_trampoline(ops);
+ if (ops->trampoline && ops->trampoline != trampoline &&
+ (ops->flags & FTRACE_OPS_FL_ALLOC_TRAMP)) {
+ /* Add to kallsyms before the perf events */
+ ftrace_add_trampoline_to_kallsyms(ops);
+ perf_event_ksymbol(PERF_RECORD_KSYMBOL_TYPE_OOL,
+ ops->trampoline, ops->trampoline_size, false,
+ FTRACE_TRAMPOLINE_SYM);
+ /*
+ * Record the perf text poke event after the ksymbol register
+ * event.
+ */
+ perf_event_text_poke((void *)ops->trampoline, NULL, 0,
+ (void *)ops->trampoline,
+ ops->trampoline_size);
+ }
}
void ftrace_init_trace_array(struct trace_array *tr)
@@ -6336,7 +6985,7 @@
struct ftrace_ops *op;
int bit;
- bit = trace_test_and_set_recursion(TRACE_LIST_START, TRACE_LIST_MAX);
+ bit = trace_test_and_set_recursion(TRACE_LIST_START);
if (bit < 0)
return;
@@ -6411,7 +7060,7 @@
{
int bit;
- bit = trace_test_and_set_recursion(TRACE_LIST_START, TRACE_LIST_MAX);
+ bit = trace_test_and_set_recursion(TRACE_LIST_START);
if (bit < 0)
return;
@@ -6455,11 +7104,17 @@
{
struct trace_array *tr = data;
struct trace_pid_list *pid_list;
+ struct trace_pid_list *no_pid_list;
pid_list = rcu_dereference_sched(tr->function_pids);
+ no_pid_list = rcu_dereference_sched(tr->function_no_pids);
- this_cpu_write(tr->trace_buffer.data->ftrace_ignore_pid,
- trace_ignore_this_task(pid_list, next));
+ if (trace_ignore_this_task(pid_list, no_pid_list, next))
+ this_cpu_write(tr->array_buffer.data->ftrace_ignore_pid,
+ FTRACE_PID_IGNORE);
+ else
+ this_cpu_write(tr->array_buffer.data->ftrace_ignore_pid,
+ next->pid);
}
static void
@@ -6472,6 +7127,9 @@
pid_list = rcu_dereference_sched(tr->function_pids);
trace_filter_add_remove_task(pid_list, self, task);
+
+ pid_list = rcu_dereference_sched(tr->function_no_pids);
+ trace_filter_add_remove_task(pid_list, self, task);
}
static void
@@ -6482,6 +7140,9 @@
pid_list = rcu_dereference_sched(tr->function_pids);
trace_filter_add_remove_task(pid_list, NULL, task);
+
+ pid_list = rcu_dereference_sched(tr->function_no_pids);
+ trace_filter_add_remove_task(pid_list, NULL, task);
}
void ftrace_pid_follow_fork(struct trace_array *tr, bool enable)
@@ -6499,42 +7160,57 @@
}
}
-static void clear_ftrace_pids(struct trace_array *tr)
+static void clear_ftrace_pids(struct trace_array *tr, int type)
{
struct trace_pid_list *pid_list;
+ struct trace_pid_list *no_pid_list;
int cpu;
pid_list = rcu_dereference_protected(tr->function_pids,
lockdep_is_held(&ftrace_lock));
- if (!pid_list)
+ no_pid_list = rcu_dereference_protected(tr->function_no_pids,
+ lockdep_is_held(&ftrace_lock));
+
+ /* Make sure there's something to do */
+ if (!pid_type_enabled(type, pid_list, no_pid_list))
return;
- unregister_trace_sched_switch(ftrace_filter_pid_sched_switch_probe, tr);
+ /* See if the pids still need to be checked after this */
+ if (!still_need_pid_events(type, pid_list, no_pid_list)) {
+ unregister_trace_sched_switch(ftrace_filter_pid_sched_switch_probe, tr);
+ for_each_possible_cpu(cpu)
+ per_cpu_ptr(tr->array_buffer.data, cpu)->ftrace_ignore_pid = FTRACE_PID_TRACE;
+ }
- for_each_possible_cpu(cpu)
- per_cpu_ptr(tr->trace_buffer.data, cpu)->ftrace_ignore_pid = false;
+ if (type & TRACE_PIDS)
+ rcu_assign_pointer(tr->function_pids, NULL);
- rcu_assign_pointer(tr->function_pids, NULL);
+ if (type & TRACE_NO_PIDS)
+ rcu_assign_pointer(tr->function_no_pids, NULL);
/* Wait till all users are no longer using pid filtering */
synchronize_rcu();
- trace_free_pid_list(pid_list);
+ if ((type & TRACE_PIDS) && pid_list)
+ trace_free_pid_list(pid_list);
+
+ if ((type & TRACE_NO_PIDS) && no_pid_list)
+ trace_free_pid_list(no_pid_list);
}
void ftrace_clear_pids(struct trace_array *tr)
{
mutex_lock(&ftrace_lock);
- clear_ftrace_pids(tr);
+ clear_ftrace_pids(tr, TRACE_PIDS | TRACE_NO_PIDS);
mutex_unlock(&ftrace_lock);
}
-static void ftrace_pid_reset(struct trace_array *tr)
+static void ftrace_pid_reset(struct trace_array *tr, int type)
{
mutex_lock(&ftrace_lock);
- clear_ftrace_pids(tr);
+ clear_ftrace_pids(tr, type);
ftrace_update_pid_func();
ftrace_startup_all(0);
@@ -6598,9 +7274,45 @@
.show = fpid_show,
};
-static int
-ftrace_pid_open(struct inode *inode, struct file *file)
+static void *fnpid_start(struct seq_file *m, loff_t *pos)
+ __acquires(RCU)
{
+ struct trace_pid_list *pid_list;
+ struct trace_array *tr = m->private;
+
+ mutex_lock(&ftrace_lock);
+ rcu_read_lock_sched();
+
+ pid_list = rcu_dereference_sched(tr->function_no_pids);
+
+ if (!pid_list)
+ return !(*pos) ? FTRACE_NO_PIDS : NULL;
+
+ return trace_pid_start(pid_list, pos);
+}
+
+static void *fnpid_next(struct seq_file *m, void *v, loff_t *pos)
+{
+ struct trace_array *tr = m->private;
+ struct trace_pid_list *pid_list = rcu_dereference_sched(tr->function_no_pids);
+
+ if (v == FTRACE_NO_PIDS) {
+ (*pos)++;
+ return NULL;
+ }
+ return trace_pid_next(pid_list, v, pos);
+}
+
+static const struct seq_operations ftrace_no_pid_sops = {
+ .start = fnpid_start,
+ .next = fnpid_next,
+ .stop = fpid_stop,
+ .show = fpid_show,
+};
+
+static int pid_open(struct inode *inode, struct file *file, int type)
+{
+ const struct seq_operations *seq_ops;
struct trace_array *tr = inode->i_private;
struct seq_file *m;
int ret = 0;
@@ -6611,9 +7323,22 @@
if ((file->f_mode & FMODE_WRITE) &&
(file->f_flags & O_TRUNC))
- ftrace_pid_reset(tr);
+ ftrace_pid_reset(tr, type);
- ret = seq_open(file, &ftrace_pid_sops);
+ switch (type) {
+ case TRACE_PIDS:
+ seq_ops = &ftrace_pid_sops;
+ break;
+ case TRACE_NO_PIDS:
+ seq_ops = &ftrace_no_pid_sops;
+ break;
+ default:
+ trace_array_put(tr);
+ WARN_ON_ONCE(1);
+ return -EINVAL;
+ }
+
+ ret = seq_open(file, seq_ops);
if (ret < 0) {
trace_array_put(tr);
} else {
@@ -6625,10 +7350,23 @@
return ret;
}
+static int
+ftrace_pid_open(struct inode *inode, struct file *file)
+{
+ return pid_open(inode, file, TRACE_PIDS);
+}
+
+static int
+ftrace_no_pid_open(struct inode *inode, struct file *file)
+{
+ return pid_open(inode, file, TRACE_NO_PIDS);
+}
+
static void ignore_task_cpu(void *data)
{
struct trace_array *tr = data;
struct trace_pid_list *pid_list;
+ struct trace_pid_list *no_pid_list;
/*
* This function is called by on_each_cpu() while the
@@ -6636,18 +7374,25 @@
*/
pid_list = rcu_dereference_protected(tr->function_pids,
mutex_is_locked(&ftrace_lock));
+ no_pid_list = rcu_dereference_protected(tr->function_no_pids,
+ mutex_is_locked(&ftrace_lock));
- this_cpu_write(tr->trace_buffer.data->ftrace_ignore_pid,
- trace_ignore_this_task(pid_list, current));
+ if (trace_ignore_this_task(pid_list, no_pid_list, current))
+ this_cpu_write(tr->array_buffer.data->ftrace_ignore_pid,
+ FTRACE_PID_IGNORE);
+ else
+ this_cpu_write(tr->array_buffer.data->ftrace_ignore_pid,
+ current->pid);
}
static ssize_t
-ftrace_pid_write(struct file *filp, const char __user *ubuf,
- size_t cnt, loff_t *ppos)
+pid_write(struct file *filp, const char __user *ubuf,
+ size_t cnt, loff_t *ppos, int type)
{
struct seq_file *m = filp->private_data;
struct trace_array *tr = m->private;
- struct trace_pid_list *filtered_pids = NULL;
+ struct trace_pid_list *filtered_pids;
+ struct trace_pid_list *other_pids;
struct trace_pid_list *pid_list;
ssize_t ret;
@@ -6656,19 +7401,43 @@
mutex_lock(&ftrace_lock);
- filtered_pids = rcu_dereference_protected(tr->function_pids,
+ switch (type) {
+ case TRACE_PIDS:
+ filtered_pids = rcu_dereference_protected(tr->function_pids,
lockdep_is_held(&ftrace_lock));
+ other_pids = rcu_dereference_protected(tr->function_no_pids,
+ lockdep_is_held(&ftrace_lock));
+ break;
+ case TRACE_NO_PIDS:
+ filtered_pids = rcu_dereference_protected(tr->function_no_pids,
+ lockdep_is_held(&ftrace_lock));
+ other_pids = rcu_dereference_protected(tr->function_pids,
+ lockdep_is_held(&ftrace_lock));
+ break;
+ default:
+ ret = -EINVAL;
+ WARN_ON_ONCE(1);
+ goto out;
+ }
ret = trace_pid_write(filtered_pids, &pid_list, ubuf, cnt);
if (ret < 0)
goto out;
- rcu_assign_pointer(tr->function_pids, pid_list);
+ switch (type) {
+ case TRACE_PIDS:
+ rcu_assign_pointer(tr->function_pids, pid_list);
+ break;
+ case TRACE_NO_PIDS:
+ rcu_assign_pointer(tr->function_no_pids, pid_list);
+ break;
+ }
+
if (filtered_pids) {
synchronize_rcu();
trace_free_pid_list(filtered_pids);
- } else if (pid_list) {
+ } else if (pid_list && !other_pids) {
/* Register a probe to set whether to ignore the tracing of a task */
register_trace_sched_switch(ftrace_filter_pid_sched_switch_probe, tr);
}
@@ -6691,6 +7460,20 @@
return ret;
}
+static ssize_t
+ftrace_pid_write(struct file *filp, const char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ return pid_write(filp, ubuf, cnt, ppos, TRACE_PIDS);
+}
+
+static ssize_t
+ftrace_no_pid_write(struct file *filp, const char __user *ubuf,
+ size_t cnt, loff_t *ppos)
+{
+ return pid_write(filp, ubuf, cnt, ppos, TRACE_NO_PIDS);
+}
+
static int
ftrace_pid_release(struct inode *inode, struct file *file)
{
@@ -6709,10 +7492,20 @@
.release = ftrace_pid_release,
};
+static const struct file_operations ftrace_no_pid_fops = {
+ .open = ftrace_no_pid_open,
+ .write = ftrace_no_pid_write,
+ .read = seq_read,
+ .llseek = tracing_lseek,
+ .release = ftrace_pid_release,
+};
+
void ftrace_init_tracefs(struct trace_array *tr, struct dentry *d_tracer)
{
trace_create_file("set_ftrace_pid", 0644, d_tracer,
tr, &ftrace_pid_fops);
+ trace_create_file("set_ftrace_notrace_pid", 0644, d_tracer,
+ tr, &ftrace_no_pid_fops);
}
void __init ftrace_init_tracefs_toplevel(struct trace_array *tr,
@@ -6792,10 +7585,21 @@
}
EXPORT_SYMBOL_GPL(unregister_ftrace_function);
+static bool is_permanent_ops_registered(void)
+{
+ struct ftrace_ops *op;
+
+ do_for_each_ftrace_op(op, ftrace_ops_list) {
+ if (op->flags & FTRACE_OPS_FL_PERMANENT)
+ return true;
+ } while_for_each_ftrace_op(op);
+
+ return false;
+}
+
int
ftrace_enable_sysctl(struct ctl_table *table, int write,
- void __user *buffer, size_t *lenp,
- loff_t *ppos)
+ void *buffer, size_t *lenp, loff_t *ppos)
{
int ret = -ENODEV;
@@ -6809,8 +7613,6 @@
if (ret || !write || (last_ftrace_enabled == !!ftrace_enabled))
goto out;
- last_ftrace_enabled = !!ftrace_enabled;
-
if (ftrace_enabled) {
/* we are starting ftrace again */
@@ -6821,12 +7623,19 @@
ftrace_startup_sysctl();
} else {
+ if (is_permanent_ops_registered()) {
+ ftrace_enabled = true;
+ ret = -EBUSY;
+ goto out;
+ }
+
/* stopping ftrace calls (just send to ftrace_stub) */
ftrace_trace_function = ftrace_stub;
ftrace_shutdown_sysctl();
}
+ last_ftrace_enabled = !!ftrace_enabled;
out:
mutex_unlock(&ftrace_lock);
return ret;