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-rw-r--r--kernel/Makefile2
-rw-r--r--kernel/events/callchain.c38
-rw-r--r--kernel/events/core.c214
-rw-r--r--kernel/events/internal.h82
-rw-r--r--kernel/events/ring_buffer.c10
-rw-r--r--kernel/events/uprobes.c248
-rw-r--r--kernel/fork.c6
-rw-r--r--kernel/kprobes.c247
-rw-r--r--kernel/trace/Kconfig10
-rw-r--r--kernel/trace/Makefile8
-rw-r--r--kernel/trace/ftrace.c322
-rw-r--r--kernel/trace/ring_buffer.c4
-rw-r--r--kernel/trace/trace.c12
-rw-r--r--kernel/trace/trace.h3
-rw-r--r--kernel/trace/trace_event_perf.c3
-rw-r--r--kernel/trace/trace_events.c116
-rw-r--r--kernel/trace/trace_events_filter.c2
-rw-r--r--kernel/trace/trace_functions.c14
-rw-r--r--kernel/trace/trace_functions_graph.c5
-rw-r--r--kernel/trace/trace_irqsoff.c5
-rw-r--r--kernel/trace/trace_sched_wakeup.c5
-rw-r--r--kernel/trace/trace_selftest.c304
-rw-r--r--kernel/trace/trace_stack.c4
-rw-r--r--kernel/trace/trace_syscalls.c2
24 files changed, 1259 insertions, 407 deletions
diff --git a/kernel/Makefile b/kernel/Makefile
index e5602d32acb3..5404911eaee9 100644
--- a/kernel/Makefile
+++ b/kernel/Makefile
@@ -97,7 +97,7 @@ obj-$(CONFIG_COMPAT_BINFMT_ELF) += elfcore.o
obj-$(CONFIG_BINFMT_ELF_FDPIC) += elfcore.o
obj-$(CONFIG_FUNCTION_TRACER) += trace/
obj-$(CONFIG_TRACING) += trace/
-obj-$(CONFIG_X86_DS) += trace/
+obj-$(CONFIG_TRACE_CLOCK) += trace/
obj-$(CONFIG_RING_BUFFER) += trace/
obj-$(CONFIG_TRACEPOINTS) += trace/
obj-$(CONFIG_IRQ_WORK) += irq_work.o
diff --git a/kernel/events/callchain.c b/kernel/events/callchain.c
index 98d4597f43d6..c77206184b8b 100644
--- a/kernel/events/callchain.c
+++ b/kernel/events/callchain.c
@@ -159,6 +159,11 @@ perf_callchain(struct perf_event *event, struct pt_regs *regs)
int rctx;
struct perf_callchain_entry *entry;
+ int kernel = !event->attr.exclude_callchain_kernel;
+ int user = !event->attr.exclude_callchain_user;
+
+ if (!kernel && !user)
+ return NULL;
entry = get_callchain_entry(&rctx);
if (rctx == -1)
@@ -169,24 +174,29 @@ perf_callchain(struct perf_event *event, struct pt_regs *regs)
entry->nr = 0;
- if (!user_mode(regs)) {
+ if (kernel && !user_mode(regs)) {
perf_callchain_store(entry, PERF_CONTEXT_KERNEL);
perf_callchain_kernel(entry, regs);
- if (current->mm)
- regs = task_pt_regs(current);
- else
- regs = NULL;
}
- if (regs) {
- /*
- * Disallow cross-task user callchains.
- */
- if (event->ctx->task && event->ctx->task != current)
- goto exit_put;
-
- perf_callchain_store(entry, PERF_CONTEXT_USER);
- perf_callchain_user(entry, regs);
+ if (user) {
+ if (!user_mode(regs)) {
+ if (current->mm)
+ regs = task_pt_regs(current);
+ else
+ regs = NULL;
+ }
+
+ if (regs) {
+ /*
+ * Disallow cross-task user callchains.
+ */
+ if (event->ctx->task && event->ctx->task != current)
+ goto exit_put;
+
+ perf_callchain_store(entry, PERF_CONTEXT_USER);
+ perf_callchain_user(entry, regs);
+ }
}
exit_put:
diff --git a/kernel/events/core.c b/kernel/events/core.c
index 7fee567153f0..7b9df353ba1b 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -36,6 +36,7 @@
#include <linux/perf_event.h>
#include <linux/ftrace_event.h>
#include <linux/hw_breakpoint.h>
+#include <linux/mm_types.h>
#include "internal.h"
@@ -3764,6 +3765,132 @@ int perf_unregister_guest_info_callbacks(struct perf_guest_info_callbacks *cbs)
}
EXPORT_SYMBOL_GPL(perf_unregister_guest_info_callbacks);
+static void
+perf_output_sample_regs(struct perf_output_handle *handle,
+ struct pt_regs *regs, u64 mask)
+{
+ int bit;
+
+ for_each_set_bit(bit, (const unsigned long *) &mask,
+ sizeof(mask) * BITS_PER_BYTE) {
+ u64 val;
+
+ val = perf_reg_value(regs, bit);
+ perf_output_put(handle, val);
+ }
+}
+
+static void perf_sample_regs_user(struct perf_regs_user *regs_user,
+ struct pt_regs *regs)
+{
+ if (!user_mode(regs)) {
+ if (current->mm)
+ regs = task_pt_regs(current);
+ else
+ regs = NULL;
+ }
+
+ if (regs) {
+ regs_user->regs = regs;
+ regs_user->abi = perf_reg_abi(current);
+ }
+}
+
+/*
+ * Get remaining task size from user stack pointer.
+ *
+ * It'd be better to take stack vma map and limit this more
+ * precisly, but there's no way to get it safely under interrupt,
+ * so using TASK_SIZE as limit.
+ */
+static u64 perf_ustack_task_size(struct pt_regs *regs)
+{
+ unsigned long addr = perf_user_stack_pointer(regs);
+
+ if (!addr || addr >= TASK_SIZE)
+ return 0;
+
+ return TASK_SIZE - addr;
+}
+
+static u16
+perf_sample_ustack_size(u16 stack_size, u16 header_size,
+ struct pt_regs *regs)
+{
+ u64 task_size;
+
+ /* No regs, no stack pointer, no dump. */
+ if (!regs)
+ return 0;
+
+ /*
+ * Check if we fit in with the requested stack size into the:
+ * - TASK_SIZE
+ * If we don't, we limit the size to the TASK_SIZE.
+ *
+ * - remaining sample size
+ * If we don't, we customize the stack size to
+ * fit in to the remaining sample size.
+ */
+
+ task_size = min((u64) USHRT_MAX, perf_ustack_task_size(regs));
+ stack_size = min(stack_size, (u16) task_size);
+
+ /* Current header size plus static size and dynamic size. */
+ header_size += 2 * sizeof(u64);
+
+ /* Do we fit in with the current stack dump size? */
+ if ((u16) (header_size + stack_size) < header_size) {
+ /*
+ * If we overflow the maximum size for the sample,
+ * we customize the stack dump size to fit in.
+ */
+ stack_size = USHRT_MAX - header_size - sizeof(u64);
+ stack_size = round_up(stack_size, sizeof(u64));
+ }
+
+ return stack_size;
+}
+
+static void
+perf_output_sample_ustack(struct perf_output_handle *handle, u64 dump_size,
+ struct pt_regs *regs)
+{
+ /* Case of a kernel thread, nothing to dump */
+ if (!regs) {
+ u64 size = 0;
+ perf_output_put(handle, size);
+ } else {
+ unsigned long sp;
+ unsigned int rem;
+ u64 dyn_size;
+
+ /*
+ * We dump:
+ * static size
+ * - the size requested by user or the best one we can fit
+ * in to the sample max size
+ * data
+ * - user stack dump data
+ * dynamic size
+ * - the actual dumped size
+ */
+
+ /* Static size. */
+ perf_output_put(handle, dump_size);
+
+ /* Data. */
+ sp = perf_user_stack_pointer(regs);
+ rem = __output_copy_user(handle, (void *) sp, dump_size);
+ dyn_size = dump_size - rem;
+
+ perf_output_skip(handle, rem);
+
+ /* Dynamic size. */
+ perf_output_put(handle, dyn_size);
+ }
+}
+
static void __perf_event_header__init_id(struct perf_event_header *header,
struct perf_sample_data *data,
struct perf_event *event)
@@ -4024,6 +4151,28 @@ void perf_output_sample(struct perf_output_handle *handle,
perf_output_put(handle, nr);
}
}
+
+ if (sample_type & PERF_SAMPLE_REGS_USER) {
+ u64 abi = data->regs_user.abi;
+
+ /*
+ * If there are no regs to dump, notice it through
+ * first u64 being zero (PERF_SAMPLE_REGS_ABI_NONE).
+ */
+ perf_output_put(handle, abi);
+
+ if (abi) {
+ u64 mask = event->attr.sample_regs_user;
+ perf_output_sample_regs(handle,
+ data->regs_user.regs,
+ mask);
+ }
+ }
+
+ if (sample_type & PERF_SAMPLE_STACK_USER)
+ perf_output_sample_ustack(handle,
+ data->stack_user_size,
+ data->regs_user.regs);
}
void perf_prepare_sample(struct perf_event_header *header,
@@ -4075,6 +4224,49 @@ void perf_prepare_sample(struct perf_event_header *header,
}
header->size += size;
}
+
+ if (sample_type & PERF_SAMPLE_REGS_USER) {
+ /* regs dump ABI info */
+ int size = sizeof(u64);
+
+ perf_sample_regs_user(&data->regs_user, regs);
+
+ if (data->regs_user.regs) {
+ u64 mask = event->attr.sample_regs_user;
+ size += hweight64(mask) * sizeof(u64);
+ }
+
+ header->size += size;
+ }
+
+ if (sample_type & PERF_SAMPLE_STACK_USER) {
+ /*
+ * Either we need PERF_SAMPLE_STACK_USER bit to be allways
+ * processed as the last one or have additional check added
+ * in case new sample type is added, because we could eat
+ * up the rest of the sample size.
+ */
+ struct perf_regs_user *uregs = &data->regs_user;
+ u16 stack_size = event->attr.sample_stack_user;
+ u16 size = sizeof(u64);
+
+ if (!uregs->abi)
+ perf_sample_regs_user(uregs, regs);
+
+ stack_size = perf_sample_ustack_size(stack_size, header->size,
+ uregs->regs);
+
+ /*
+ * If there is something to dump, add space for the dump
+ * itself and for the field that tells the dynamic size,
+ * which is how many have been actually dumped.
+ */
+ if (stack_size)
+ size += sizeof(u64) + stack_size;
+
+ data->stack_user_size = stack_size;
+ header->size += size;
+ }
}
static void perf_event_output(struct perf_event *event,
@@ -6151,6 +6343,28 @@ static int perf_copy_attr(struct perf_event_attr __user *uattr,
attr->branch_sample_type = mask;
}
}
+
+ if (attr->sample_type & PERF_SAMPLE_REGS_USER) {
+ ret = perf_reg_validate(attr->sample_regs_user);
+ if (ret)
+ return ret;
+ }
+
+ if (attr->sample_type & PERF_SAMPLE_STACK_USER) {
+ if (!arch_perf_have_user_stack_dump())
+ return -ENOSYS;
+
+ /*
+ * We have __u32 type for the size, but so far
+ * we can only use __u16 as maximum due to the
+ * __u16 sample size limit.
+ */
+ if (attr->sample_stack_user >= USHRT_MAX)
+ ret = -EINVAL;
+ else if (!IS_ALIGNED(attr->sample_stack_user, sizeof(u64)))
+ ret = -EINVAL;
+ }
+
out:
return ret;
diff --git a/kernel/events/internal.h b/kernel/events/internal.h
index a096c19f2c2a..d56a64c99a8b 100644
--- a/kernel/events/internal.h
+++ b/kernel/events/internal.h
@@ -2,6 +2,7 @@
#define _KERNEL_EVENTS_INTERNAL_H
#include <linux/hardirq.h>
+#include <linux/uaccess.h>
/* Buffer handling */
@@ -76,30 +77,53 @@ static inline unsigned long perf_data_size(struct ring_buffer *rb)
return rb->nr_pages << (PAGE_SHIFT + page_order(rb));
}
-static inline void
-__output_copy(struct perf_output_handle *handle,
- const void *buf, unsigned int len)
+#define DEFINE_OUTPUT_COPY(func_name, memcpy_func) \
+static inline unsigned int \
+func_name(struct perf_output_handle *handle, \
+ const void *buf, unsigned int len) \
+{ \
+ unsigned long size, written; \
+ \
+ do { \
+ size = min_t(unsigned long, handle->size, len); \
+ \
+ written = memcpy_func(handle->addr, buf, size); \
+ \
+ len -= written; \
+ handle->addr += written; \
+ buf += written; \
+ handle->size -= written; \
+ if (!handle->size) { \
+ struct ring_buffer *rb = handle->rb; \
+ \
+ handle->page++; \
+ handle->page &= rb->nr_pages - 1; \
+ handle->addr = rb->data_pages[handle->page]; \
+ handle->size = PAGE_SIZE << page_order(rb); \
+ } \
+ } while (len && written == size); \
+ \
+ return len; \
+}
+
+static inline int memcpy_common(void *dst, const void *src, size_t n)
{
- do {
- unsigned long size = min_t(unsigned long, handle->size, len);
-
- memcpy(handle->addr, buf, size);
-
- len -= size;
- handle->addr += size;
- buf += size;
- handle->size -= size;
- if (!handle->size) {
- struct ring_buffer *rb = handle->rb;
-
- handle->page++;
- handle->page &= rb->nr_pages - 1;
- handle->addr = rb->data_pages[handle->page];
- handle->size = PAGE_SIZE << page_order(rb);
- }
- } while (len);
+ memcpy(dst, src, n);
+ return n;
}
+DEFINE_OUTPUT_COPY(__output_copy, memcpy_common)
+
+#define MEMCPY_SKIP(dst, src, n) (n)
+
+DEFINE_OUTPUT_COPY(__output_skip, MEMCPY_SKIP)
+
+#ifndef arch_perf_out_copy_user
+#define arch_perf_out_copy_user __copy_from_user_inatomic
+#endif
+
+DEFINE_OUTPUT_COPY(__output_copy_user, arch_perf_out_copy_user)
+
/* Callchain handling */
extern struct perf_callchain_entry *
perf_callchain(struct perf_event *event, struct pt_regs *regs);
@@ -134,4 +158,20 @@ static inline void put_recursion_context(int *recursion, int rctx)
recursion[rctx]--;
}
+#ifdef CONFIG_HAVE_PERF_USER_STACK_DUMP
+static inline bool arch_perf_have_user_stack_dump(void)
+{
+ return true;
+}
+
+#define perf_user_stack_pointer(regs) user_stack_pointer(regs)
+#else
+static inline bool arch_perf_have_user_stack_dump(void)
+{
+ return false;
+}
+
+#define perf_user_stack_pointer(regs) 0
+#endif /* CONFIG_HAVE_PERF_USER_STACK_DUMP */
+
#endif /* _KERNEL_EVENTS_INTERNAL_H */
diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c
index 6ddaba43fb7a..23cb34ff3973 100644
--- a/kernel/events/ring_buffer.c
+++ b/kernel/events/ring_buffer.c
@@ -182,10 +182,16 @@ out:
return -ENOSPC;
}
-void perf_output_copy(struct perf_output_handle *handle,
+unsigned int perf_output_copy(struct perf_output_handle *handle,
const void *buf, unsigned int len)
{
- __output_copy(handle, buf, len);
+ return __output_copy(handle, buf, len);
+}
+
+unsigned int perf_output_skip(struct perf_output_handle *handle,
+ unsigned int len)
+{
+ return __output_skip(handle, NULL, len);
}
void perf_output_end(struct perf_output_handle *handle)
diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
index c08a22d02f72..912ef48d28ab 100644
--- a/kernel/events/uprobes.c
+++ b/kernel/events/uprobes.c
@@ -280,12 +280,10 @@ static int read_opcode(struct mm_struct *mm, unsigned long vaddr, uprobe_opcode_
if (ret <= 0)
return ret;
- lock_page(page);
vaddr_new = kmap_atomic(page);
vaddr &= ~PAGE_MASK;
memcpy(opcode, vaddr_new + vaddr, UPROBE_SWBP_INSN_SIZE);
kunmap_atomic(vaddr_new);
- unlock_page(page);
put_page(page);
@@ -334,7 +332,7 @@ int __weak set_swbp(struct arch_uprobe *auprobe, struct mm_struct *mm, unsigned
*/
result = is_swbp_at_addr(mm, vaddr);
if (result == 1)
- return -EEXIST;
+ return 0;
if (result)
return result;
@@ -347,24 +345,22 @@ int __weak set_swbp(struct arch_uprobe *auprobe, struct mm_struct *mm, unsigned
* @mm: the probed process address space.
* @auprobe: arch specific probepoint information.
* @vaddr: the virtual address to insert the opcode.
- * @verify: if true, verify existance of breakpoint instruction.
*
* For mm @mm, restore the original opcode (opcode) at @vaddr.
* Return 0 (success) or a negative errno.
*/
int __weak
-set_orig_insn(struct arch_uprobe *auprobe, struct mm_struct *mm, unsigned long vaddr, bool verify)
+set_orig_insn(struct arch_uprobe *auprobe, struct mm_struct *mm, unsigned long vaddr)
{
- if (verify) {
- int result;
+ int result;
+
+ result = is_swbp_at_addr(mm, vaddr);
+ if (!result)
+ return -EINVAL;
- result = is_swbp_at_addr(mm, vaddr);
- if (!result)
- return -EINVAL;
+ if (result != 1)
+ return result;
- if (result != 1)
- return result;
- }
return write_opcode(auprobe, mm, vaddr, *(uprobe_opcode_t *)auprobe->insn);
}
@@ -415,11 +411,10 @@ static struct uprobe *__find_uprobe(struct inode *inode, loff_t offset)
static struct uprobe *find_uprobe(struct inode *inode, loff_t offset)
{
struct uprobe *uprobe;
- unsigned long flags;
- spin_lock_irqsave(&uprobes_treelock, flags);
+ spin_lock(&uprobes_treelock);
uprobe = __find_uprobe(inode, offset);
- spin_unlock_irqrestore(&uprobes_treelock, flags);
+ spin_unlock(&uprobes_treelock);
return uprobe;
}
@@ -466,12 +461,11 @@ static struct uprobe *__insert_uprobe(struct uprobe *uprobe)
*/
static struct uprobe *insert_uprobe(struct uprobe *uprobe)
{
- unsigned long flags;
struct uprobe *u;
- spin_lock_irqsave(&uprobes_treelock, flags);
+ spin_lock(&uprobes_treelock);
u = __insert_uprobe(uprobe);
- spin_unlock_irqrestore(&uprobes_treelock, flags);
+ spin_unlock(&uprobes_treelock);
/* For now assume that the instruction need not be single-stepped */
uprobe->flags |= UPROBE_SKIP_SSTEP;
@@ -649,6 +643,7 @@ static int
install_breakpoint(struct uprobe *uprobe, struct mm_struct *mm,
struct vm_area_struct *vma, unsigned long vaddr)
{
+ bool first_uprobe;
int ret;
/*
@@ -659,7 +654,7 @@ install_breakpoint(struct uprobe *uprobe, struct mm_struct *mm,
* Hence behave as if probe already existed.
*/
if (!uprobe->consumers)
- return -EEXIST;
+ return 0;
if (!(uprobe->flags & UPROBE_COPY_INSN)) {
ret = copy_insn(uprobe, vma->vm_file);
@@ -681,17 +676,18 @@ install_breakpoint(struct uprobe *uprobe, struct mm_struct *mm,
}
/*
- * Ideally, should be updating the probe count after the breakpoint
- * has been successfully inserted. However a thread could hit the
- * breakpoint we just inserted even before the probe count is
- * incremented. If this is the first breakpoint placed, breakpoint
- * notifier might ignore uprobes and pass the trap to the thread.
- * Hence increment before and decrement on failure.
+ * set MMF_HAS_UPROBES in advance for uprobe_pre_sstep_notifier(),
+ * the task can hit this breakpoint right after __replace_page().
*/
- atomic_inc(&mm->uprobes_state.count);
+ first_uprobe = !test_bit(MMF_HAS_UPROBES, &mm->flags);
+ if (first_uprobe)
+ set_bit(MMF_HAS_UPROBES, &mm->flags);
+
ret = set_swbp(&uprobe->arch, mm, vaddr);
- if (ret)
- atomic_dec(&mm->uprobes_state.count);
+ if (!ret)
+ clear_bit(MMF_RECALC_UPROBES, &mm->flags);
+ else if (first_uprobe)
+ clear_bit(MMF_HAS_UPROBES, &mm->flags);
return ret;
}
@@ -699,8 +695,12 @@ install_breakpoint(struct uprobe *uprobe, struct mm_struct *mm,
static void
remove_breakpoint(struct uprobe *uprobe, struct mm_struct *mm, unsigned long vaddr)
{
- if (!set_orig_insn(&uprobe->arch, mm, vaddr, true))
- atomic_dec(&mm->uprobes_state.count);
+ /* can happen if uprobe_register() fails */
+ if (!test_bit(MMF_HAS_UPROBES, &mm->flags))
+ return;
+
+ set_bit(MMF_RECALC_UPROBES, &mm->flags);
+ set_orig_insn(&uprobe->arch, mm, vaddr);
}
/*
@@ -710,11 +710,9 @@ remove_breakpoint(struct uprobe *uprobe, struct mm_struct *mm, unsigned long vad
*/
static void delete_uprobe(struct uprobe *uprobe)
{
- unsigned long flags;
-
- spin_lock_irqsave(&uprobes_treelock, flags);
+ spin_lock(&uprobes_treelock);
rb_erase(&uprobe->rb_node, &uprobes_tree);
- spin_unlock_irqrestore(&uprobes_treelock, flags);
+ spin_unlock(&uprobes_treelock);
iput(uprobe->inode);
put_uprobe(uprobe);
atomic_dec(&uprobe_events);
@@ -831,17 +829,11 @@ static int register_for_each_vma(struct uprobe *uprobe, bool is_register)
vaddr_to_offset(vma, info->vaddr) != uprobe->offset)
goto unlock;
- if (is_register) {
+ if (is_register)
err = install_breakpoint(uprobe, mm, vma, info->vaddr);
- /*
- * We can race against uprobe_mmap(), see the
- * comment near uprobe_hash().
- */
- if (err == -EEXIST)
- err = 0;
- } else {
+ else
remove_breakpoint(uprobe, mm, info->vaddr);
- }
+
unlock:
up_write(&mm->mmap_sem);
free:
@@ -908,7 +900,8 @@ int uprobe_register(struct inode *inode, loff_t offset, struct uprobe_consumer *
}
mutex_unlock(uprobes_hash(inode));
- put_uprobe(uprobe);
+ if (uprobe)
+ put_uprobe(uprobe);
return ret;
}
@@ -978,7 +971,6 @@ static void build_probe_list(struct inode *inode,
struct list_head *head)
{
loff_t min, max;
- unsigned long flags;
struct rb_node *n, *t;
struct uprobe *u;
@@ -986,7 +978,7 @@ static void build_probe_list(struct inode *inode,
min = vaddr_to_offset(vma, start);
max = min + (end - start) - 1;
- spin_lock_irqsave(&uprobes_treelock, flags);
+ spin_lock(&uprobes_treelock);
n = find_node_in_range(inode, min, max);
if (n) {
for (t = n; t; t = rb_prev(t)) {
@@ -1004,27 +996,20 @@ static void build_probe_list(struct inode *inode,
atomic_inc(&u->ref);
}
}
- spin_unlock_irqrestore(&uprobes_treelock, flags);
+ spin_unlock(&uprobes_treelock);
}
/*
- * Called from mmap_region.
- * called with mm->mmap_sem acquired.
+ * Called from mmap_region/vma_adjust with mm->mmap_sem acquired.
*
- * Return -ve no if we fail to insert probes and we cannot
- * bail-out.
- * Return 0 otherwise. i.e:
- *
- * - successful insertion of probes
- * - (or) no possible probes to be inserted.
- * - (or) insertion of probes failed but we can bail-out.
+ * Currently we ignore all errors and always return 0, the callers
+ * can't handle the failure anyway.
*/
int uprobe_mmap(struct vm_area_struct *vma)
{
struct list_head tmp_list;
struct uprobe *uprobe, *u;
struct inode *inode;
- int ret, count;
if (!atomic_read(&uprobe_events) || !valid_vma(vma, true))
return 0;
@@ -1036,44 +1021,35 @@ int uprobe_mmap(struct vm_area_struct *vma)
mutex_lock(uprobes_mmap_hash(inode));
build_probe_list(inode, vma, vma->vm_start, vma->vm_end, &tmp_list);
- ret = 0;
- count = 0;
-
list_for_each_entry_safe(uprobe, u, &tmp_list, pending_list) {
- if (!ret) {
+ if (!fatal_signal_pending(current)) {
unsigned long vaddr = offset_to_vaddr(vma, uprobe->offset);
-
- ret = install_breakpoint(uprobe, vma->vm_mm, vma, vaddr);
- /*
- * We can race against uprobe_register(), see the
- * comment near uprobe_hash().
- */
- if (ret == -EEXIST) {
- ret = 0;
-
- if (!is_swbp_at_addr(vma->vm_mm, vaddr))
- continue;
-
- /*
- * Unable to insert a breakpoint, but
- * breakpoint lies underneath. Increment the
- * probe count.
- */
- atomic_inc(&vma->vm_mm->uprobes_state.count);
- }
-
- if (!ret)
- count++;
+ install_breakpoint(uprobe, vma->vm_mm, vma, vaddr);
}
put_uprobe(uprobe);
}
-
mutex_unlock(uprobes_mmap_hash(inode));
- if (ret)
- atomic_sub(count, &vma->vm_mm->uprobes_state.count);
+ return 0;
+}
- return ret;
+static bool
+vma_has_uprobes(struct vm_area_struct *vma, unsigned long start, unsigned long end)
+{
+ loff_t min, max;
+ struct inode *inode;
+ struct rb_node *n;
+
+ inode = vma->vm_file->f_mapping->host;
+
+ min = vaddr_to_offset(vma, start);
+ max = min + (end - start) - 1;
+
+ spin_lock(&uprobes_treelock);
+ n = find_node_in_range(inode, min, max);
+ spin_unlock(&uprobes_treelock);
+
+ return !!n;
}
/*
@@ -1081,37 +1057,18 @@ int uprobe_mmap(struct vm_area_struct *vma)
*/
void uprobe_munmap(struct vm_area_struct *vma, unsigned long start, unsigned long end)
{
- struct list_head tmp_list;
- struct uprobe *uprobe, *u;
- struct inode *inode;
-
if (!atomic_read(&uprobe_events) || !valid_vma(vma, false))
return;
if (!atomic_read(&vma->vm_mm->mm_users)) /* called by mmput() ? */
return;
- if (!atomic_read(&vma->vm_mm->uprobes_state.count))
- return;
-
- inode = vma->vm_file->f_mapping->host;
- if (!inode)
+ if (!test_bit(MMF_HAS_UPROBES, &vma->vm_mm->flags) ||
+ test_bit(MMF_RECALC_UPROBES, &vma->vm_mm->flags))
return;
- mutex_lock(uprobes_mmap_hash(inode));
- build_probe_list(inode, vma, start, end, &tmp_list);
-
- list_for_each_entry_safe(uprobe, u, &tmp_list, pending_list) {
- unsigned long vaddr = offset_to_vaddr(vma, uprobe->offset);
- /*
- * An unregister could have removed the probe before
- * unmap. So check before we decrement the count.
- */
- if (is_swbp_at_addr(vma->vm_mm, vaddr) == 1)
- atomic_dec(&vma->vm_mm->uprobes_state.count);
- put_uprobe(uprobe);
- }
- mutex_unlock(uprobes_mmap_hash(inode));
+ if (vma_has_uprobes(vma, start, end))
+ set_bit(MMF_RECALC_UPROBES, &vma->vm_mm->flags);
}
/* Slot allocation for XOL */
@@ -1213,13 +1170,15 @@ void uprobe_clear_state(struct mm_struct *mm)
kfree(area);
}
-/*
- * uprobe_reset_state - Free the area allocated for slots.
- */
-void uprobe_reset_state(struct mm_struct *mm)
+void uprobe_dup_mmap(struct mm_struct *oldmm, struct mm_struct *newmm)
{
- mm->uprobes_state.xol_area = NULL;
- atomic_set(&mm->uprobes_state.count, 0);
+ newmm->uprobes_state.xol_area = NULL;
+
+ if (test_bit(MMF_HAS_UPROBES, &oldmm->flags)) {
+ set_bit(MMF_HAS_UPROBES, &newmm->flags);
+ /* unconditionally, dup_mmap() skips VM_DONTCOPY vmas */
+ set_bit(MMF_RECALC_UPROBES, &newmm->flags);
+ }
}
/*
@@ -1437,6 +1396,25 @@ static bool can_skip_sstep(struct uprobe *uprobe, struct pt_regs *regs)
return false;
}
+static void mmf_recalc_uprobes(struct mm_struct *mm)
+{
+ struct vm_area_struct *vma;
+
+ for (vma = mm->mmap; vma; vma = vma->vm_next) {
+ if (!valid_vma(vma, false))
+ continue;
+ /*
+ * This is not strictly accurate, we can race with
+ * uprobe_unregister() and see the already removed
+ * uprobe if delete_uprobe() was not yet called.
+ */
+ if (vma_has_uprobes(vma, vma->vm_start, vma->vm_end))
+ return;
+ }
+
+ clear_bit(MMF_HAS_UPROBES, &mm->flags);
+}
+
static struct uprobe *find_active_uprobe(unsigned long bp_vaddr, int *is_swbp)
{
struct mm_struct *mm = current->mm;
@@ -1458,11 +1436,24 @@ static struct uprobe *find_active_uprobe(unsigned long bp_vaddr, int *is_swbp)
} else {
*is_swbp = -EFAULT;
}
+
+ if (!uprobe && test_and_clear_bit(MMF_RECALC_UPROBES, &mm->flags))
+ mmf_recalc_uprobes(mm);
up_read(&mm->mmap_sem);
return uprobe;
}
+void __weak arch_uprobe_enable_step(struct arch_uprobe *arch)
+{
+ user_enable_single_step(current);
+}
+
+void __weak arch_uprobe_disable_step(struct arch_uprobe *arch)
+{
+ user_disable_single_step(current);
+}
+
/*
* Run handler and ask thread to singlestep.
* Ensure all non-fatal signals cannot interrupt thread while it singlesteps.
@@ -1509,7 +1500,7 @@ static void handle_swbp(struct pt_regs *regs)
utask->state = UTASK_SSTEP;
if (!pre_ssout(uprobe, regs, bp_vaddr)) {
- user_enable_single_step(current);
+ arch_uprobe_enable_step(&uprobe->arch);
return;
}
@@ -1518,17 +1509,15 @@ cleanup_ret:
utask->active_uprobe = NULL;
utask->state = UTASK_RUNNING;
}
- if (uprobe) {
- if (!(uprobe->flags & UPROBE_SKIP_SSTEP))
+ if (!(uprobe->flags & UPROBE_SKIP_SSTEP))
- /*
- * cannot singlestep; cannot skip instruction;
- * re-execute the instruction.
- */
- instruction_pointer_set(regs, bp_vaddr);
+ /*
+ * cannot singlestep; cannot skip instruction;
+ * re-execute the instruction.
+ */
+ instruction_pointer_set(regs, bp_vaddr);
- put_uprobe(uprobe);
- }
+ put_uprobe(uprobe);
}
/*
@@ -1547,10 +1536,10 @@ static void handle_singlestep(struct uprobe_task *utask, struct pt_regs *regs)
else
WARN_ON_ONCE(1);
+ arch_uprobe_disable_step(&uprobe->arch);
put_uprobe(uprobe);
utask->active_uprobe = NULL;
utask->state = UTASK_RUNNING;
- user_disable_single_step(current);
xol_free_insn_slot(current);
spin_lock_irq(&current->sighand->siglock);
@@ -1589,8 +1578,7 @@ int uprobe_pre_sstep_notifier(struct pt_regs *regs)
{
struct uprobe_task *utask;
- if (!current->mm || !atomic_read(&current->mm->uprobes_state.count))
- /* task is currently not uprobed */
+ if (!current->mm || !test_bit(MMF_HAS_UPROBES, &current->mm->flags))
return 0;
utask = current->utask;
diff --git a/kernel/fork.c b/kernel/fork.c
index 2c8857e12855..2343c9eaaaf4 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -353,6 +353,7 @@ static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm)
down_write(&oldmm->mmap_sem);
flush_cache_dup_mm(oldmm);
+ uprobe_dup_mmap(oldmm, mm);
/*
* Not linked in yet - no deadlock potential:
*/
@@ -454,9 +455,6 @@ static int dup_mmap(struct mm_struct *mm, struct mm_struct *oldmm)
if (retval)
goto out;
-
- if (file)
- uprobe_mmap(tmp);
}
/* a new mm has just been created */
arch_dup_mmap(oldmm, mm);
@@ -839,8 +837,6 @@ struct mm_struct *dup_mm(struct task_struct *tsk)
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
mm->pmd_huge_pte = NULL;
#endif
- uprobe_reset_state(mm);
-
if (!mm_init(mm, tsk))
goto fail_nomem;
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index c62b8546cc90..098f396aa409 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -561,9 +561,9 @@ static __kprobes void kprobe_optimizer(struct work_struct *work)
{
LIST_HEAD(free_list);
+ mutex_lock(&kprobe_mutex);
/* Lock modules while optimizing kprobes */
mutex_lock(&module_mutex);
- mutex_lock(&kprobe_mutex);
/*
* Step 1: Unoptimize kprobes and collect cleaned (unused and disarmed)
@@ -586,8 +586,8 @@ static __kprobes void kprobe_optimizer(struct work_struct *work)
/* Step 4: Free cleaned kprobes after quiesence period */
do_free_cleaned_kprobes(&free_list);
- mutex_unlock(&kprobe_mutex);
mutex_unlock(&module_mutex);
+ mutex_unlock(&kprobe_mutex);
/* Step 5: Kick optimizer again if needed */
if (!list_empty(&optimizing_list) || !list_empty(&unoptimizing_list))
@@ -759,20 +759,32 @@ static __kprobes void try_to_optimize_kprobe(struct kprobe *p)
struct kprobe *ap;
struct optimized_kprobe *op;
+ /* Impossible to optimize ftrace-based kprobe */
+ if (kprobe_ftrace(p))
+ return;
+
+ /* For preparing optimization, jump_label_text_reserved() is called */
+ jump_label_lock();
+ mutex_lock(&text_mutex);
+
ap = alloc_aggr_kprobe(p);
if (!ap)
- return;
+ goto out;
op = container_of(ap, struct optimized_kprobe, kp);
if (!arch_prepared_optinsn(&op->optinsn)) {
/* If failed to setup optimizing, fallback to kprobe */
arch_remove_optimized_kprobe(op);
kfree(op);
- return;
+ goto out;
}
init_aggr_kprobe(ap, p);
- optimize_kprobe(ap);
+ optimize_kprobe(ap); /* This just kicks optimizer thread */
+
+out:
+ mutex_unlock(&text_mutex);
+ jump_label_unlock();
}
#ifdef CONFIG_SYSCTL
@@ -907,9 +919,64 @@ static __kprobes struct kprobe *alloc_aggr_kprobe(struct kprobe *p)
}
#endif /* CONFIG_OPTPROBES */
+#ifdef KPROBES_CAN_USE_FTRACE
+static struct ftrace_ops kprobe_ftrace_ops __read_mostly = {
+ .func = kprobe_ftrace_handler,
+ .flags = FTRACE_OPS_FL_SAVE_REGS,
+};
+static int kprobe_ftrace_enabled;
+
+/* Must ensure p->addr is really on ftrace */
+static int __kprobes prepare_kprobe(struct kprobe *p)
+{
+ if (!kprobe_ftrace(p))
+ return arch_prepare_kprobe(p);
+
+ return arch_prepare_kprobe_ftrace(p);
+}
+
+/* Caller must lock kprobe_mutex */
+static void __kprobes arm_kprobe_ftrace(struct kprobe *p)
+{
+ int ret;
+
+ ret = ftrace_set_filter_ip(&kprobe_ftrace_ops,
+ (unsigned long)p->addr, 0, 0);
+ WARN(ret < 0, "Failed to arm kprobe-ftrace at %p (%d)\n", p->addr, ret);
+ kprobe_ftrace_enabled++;
+ if (kprobe_ftrace_enabled == 1) {
+ ret = register_ftrace_function(&kprobe_ftrace_ops);
+ WARN(ret < 0, "Failed to init kprobe-ftrace (%d)\n", ret);
+ }
+}
+
+/* Caller must lock kprobe_mutex */
+static void __kprobes disarm_kprobe_ftrace(struct kprobe *p)
+{
+ int ret;
+
+ kprobe_ftrace_enabled--;
+ if (kprobe_ftrace_enabled == 0) {
+ ret = unregister_ftrace_function(&kprobe_ftrace_ops);
+ WARN(ret < 0, "Failed to init kprobe-ftrace (%d)\n", ret);
+ }
+ ret = ftrace_set_filter_ip(&kprobe_ftrace_ops,
+ (unsigned long)p->addr, 1, 0);
+ WARN(ret < 0, "Failed to disarm kprobe-ftrace at %p (%d)\n", p->addr, ret);
+}
+#else /* !KPROBES_CAN_USE_FTRACE */
+#define prepare_kprobe(p) arch_prepare_kprobe(p)
+#define arm_kprobe_ftrace(p) do {} while (0)
+#define disarm_kprobe_ftrace(p) do {} while (0)
+#endif
+
/* Arm a kprobe with text_mutex */
static void __kprobes arm_kprobe(struct kprobe *kp)
{
+ if (unlikely(kprobe_ftrace(kp))) {
+ arm_kprobe_ftrace(kp);
+ return;
+ }
/*
* Here, since __arm_kprobe() doesn't use stop_machine(),
* this doesn't cause deadlock on text_mutex. So, we don't
@@ -921,11 +988,15 @@ static void __kprobes arm_kprobe(struct kprobe *kp)
}
/* Disarm a kprobe with text_mutex */
-static void __kprobes disarm_kprobe(struct kprobe *kp)
+static void __kprobes disarm_kprobe(struct kprobe *kp, bool reopt)
{
+ if (unlikely(kprobe_ftrace(kp))) {
+ disarm_kprobe_ftrace(kp);
+ return;
+ }
/* Ditto */
mutex_lock(&text_mutex);
- __disarm_kprobe(kp, true);
+ __disarm_kprobe(kp, reopt);
mutex_unlock(&text_mutex);
}
@@ -1144,12 +1215,6 @@ static int __kprobes add_new_kprobe(struct kprobe *ap, struct kprobe *p)
if (p->post_handler && !ap->post_handler)
ap->post_handler = aggr_post_handler;
- if (kprobe_disabled(ap) && !kprobe_disabled(p)) {
- ap->flags &= ~KPROBE_FLAG_DISABLED;
- if (!kprobes_all_disarmed)
- /* Arm the breakpoint again. */
- __arm_kprobe(ap);
- }
return 0;
}
@@ -1189,11 +1254,22 @@ static int __kprobes register_aggr_kprobe(struct kprobe *orig_p,
int ret = 0;
struct kprobe *ap = orig_p;
+ /* For preparing optimization, jump_label_text_reserved() is called */
+ jump_label_lock();
+ /*
+ * Get online CPUs to avoid text_mutex deadlock.with stop machine,
+ * which is invoked by unoptimize_kprobe() in add_new_kprobe()
+ */
+ get_online_cpus();
+ mutex_lock(&text_mutex);
+
if (!kprobe_aggrprobe(orig_p)) {
/* If orig_p is not an aggr_kprobe, create new aggr_kprobe. */
ap = alloc_aggr_kprobe(orig_p);
- if (!ap)
- return -ENOMEM;
+ if (!ap) {
+ ret = -ENOMEM;
+ goto out;
+ }
init_aggr_kprobe(ap, orig_p);
} else if (kprobe_unused(ap))
/* This probe is going to die. Rescue it */
@@ -1213,7 +1289,7 @@ static int __kprobes register_aggr_kprobe(struct kprobe *orig_p,
* free aggr_probe. It will be used next time, or
* freed by unregister_kprobe.
*/
- return ret;
+ goto out;
/* Prepare optimized instructions if possible. */
prepare_optimized_kprobe(ap);
@@ -1228,7 +1304,20 @@ static int __kprobes register_aggr_kprobe(struct kprobe *orig_p,
/* Copy ap's insn slot to p */
copy_kprobe(ap, p);
- return add_new_kprobe(ap, p);
+ ret = add_new_kprobe(ap, p);
+
+out:
+ mutex_unlock(&text_mutex);
+ put_online_cpus();
+ jump_label_unlock();
+
+ if (ret == 0 && kprobe_disabled(ap) && !kprobe_disabled(p)) {
+ ap->flags &= ~KPROBE_FLAG_DISABLED;
+ if (!kprobes_all_disarmed)
+ /* Arm the breakpoint again. */
+ arm_kprobe(ap);
+ }
+ return ret;
}
static int __kprobes in_kprobes_functions(unsigned long addr)
@@ -1313,71 +1402,96 @@ static inline int check_kprobe_rereg(struct kprobe *p)
return ret;
}
-int __kprobes register_kprobe(struct kprobe *p)
+static __kprobes int check_kprobe_address_safe(struct kprobe *p,
+ struct module **probed_mod)
{
int ret = 0;
- struct kprobe *old_p;
- struct module *probed_mod;
- kprobe_opcode_t *addr;
-
- addr = kprobe_addr(p);
- if (IS_ERR(addr))
- return PTR_ERR(addr);
- p->addr = addr;
+ unsigned long ftrace_addr;
- ret = check_kprobe_rereg(p);
- if (ret)
- return ret;
+ /*
+ * If the address is located on a ftrace nop, set the
+ * breakpoint to the following instruction.
+ */
+ ftrace_addr = ftrace_location((unsigned long)p->addr);
+ if (ftrace_addr) {
+#ifdef KPROBES_CAN_USE_FTRACE
+ /* Given address is not on the instruction boundary */
+ if ((unsigned long)p->addr != ftrace_addr)
+ return -EILSEQ;
+ p->flags |= KPROBE_FLAG_FTRACE;
+#else /* !KPROBES_CAN_USE_FTRACE */
+ return -EINVAL;
+#endif
+ }
jump_label_lock();
preempt_disable();
+
+ /* Ensure it is not in reserved area nor out of text */
if (!kernel_text_address((unsigned long) p->addr) ||
in_kprobes_functions((unsigned long) p->addr) ||
- ftrace_text_reserved(p->addr, p->addr) ||
jump_label_text_reserved(p->addr, p->addr)) {
ret = -EINVAL;
- goto cannot_probe;
+ goto out;
}
- /* User can pass only KPROBE_FLAG_DISABLED to register_kprobe */
- p->flags &= KPROBE_FLAG_DISABLED;
-
- /*
- * Check if are we probing a module.
- */
- probed_mod = __module_text_address((unsigned long) p->addr);
- if (probed_mod) {
- /* Return -ENOENT if fail. */
- ret = -ENOENT;
+ /* Check if are we probing a module */
+ *probed_mod = __module_text_address((unsigned long) p->addr);
+ if (*probed_mod) {
/*
* We must hold a refcount of the probed module while updating
* its code to prohibit unexpected unloading.
*/
- if (unlikely(!try_module_get(probed_mod)))
- goto cannot_probe;
+ if (unlikely(!try_module_get(*probed_mod))) {
+ ret = -ENOENT;
+ goto out;
+ }
/*
* If the module freed .init.text, we couldn't insert
* kprobes in there.
*/
- if (within_module_init((unsigned long)p->addr, probed_mod) &&
- probed_mod->state != MODULE_STATE_COMING) {
- module_put(probed_mod);
- goto cannot_probe;
+ if (within_module_init((unsigned long)p->addr, *probed_mod) &&
+ (*probed_mod)->state != MODULE_STATE_COMING) {
+ module_put(*probed_mod);
+ *probed_mod = NULL;
+ ret = -ENOENT;
}
- /* ret will be updated by following code */
}
+out:
preempt_enable();
jump_label_unlock();
+ return ret;
+}
+
+int __kprobes register_kprobe(struct kprobe *p)
+{
+ int ret;
+ struct kprobe *old_p;
+ struct module *probed_mod;
+ kprobe_opcode_t *addr;
+
+ /* Adjust probe address from symbol */
+ addr = kprobe_addr(p);
+ if (IS_ERR(addr))
+ return PTR_ERR(addr);
+ p->addr = addr;
+
+ ret = check_kprobe_rereg(p);
+ if (ret)
+ return ret;
+
+ /* User can pass only KPROBE_FLAG_DISABLED to register_kprobe */
+ p->flags &= KPROBE_FLAG_DISABLED;
p->nmissed = 0;
INIT_LIST_HEAD(&p->list);
- mutex_lock(&kprobe_mutex);
- jump_label_lock(); /* needed to call jump_label_text_reserved() */
+ ret = check_kprobe_address_safe(p, &probed_mod);
+ if (ret)
+ return ret;
- get_online_cpus(); /* For avoiding text_mutex deadlock. */
- mutex_lock(&text_mutex);
+ mutex_lock(&kprobe_mutex);
old_p = get_kprobe(p->addr);
if (old_p) {
@@ -1386,7 +1500,9 @@ int __kprobes register_kprobe(struct kprobe *p)
goto out;
}
- ret = arch_prepare_kprobe(p);
+ mutex_lock(&text_mutex); /* Avoiding text modification */
+ ret = prepare_kprobe(p);
+ mutex_unlock(&text_mutex);
if (ret)
goto out;
@@ -1395,26 +1511,18 @@ int __kprobes register_kprobe(struct kprobe *p)
&kprobe_table[hash_ptr(p->addr, KPROBE_HASH_BITS)]);
if (!kprobes_all_disarmed && !kprobe_disabled(p))
- __arm_kprobe(p);
+ arm_kprobe(p);
/* Try to optimize kprobe */
try_to_optimize_kprobe(p);
out:
- mutex_unlock(&text_mutex);
- put_online_cpus();
- jump_label_unlock();
mutex_unlock(&kprobe_mutex);
if (probed_mod)
module_put(probed_mod);
return ret;
-
-cannot_probe:
- preempt_enable();
- jump_label_unlock();
- return ret;
}
EXPORT_SYMBOL_GPL(register_kprobe);
@@ -1451,7 +1559,7 @@ static struct kprobe *__kprobes __disable_kprobe(struct kprobe *p)
/* Try to disarm and disable this/parent probe */
if (p == orig_p || aggr_kprobe_disabled(orig_p)) {
- disarm_kprobe(orig_p);
+ disarm_kprobe(orig_p, true);
orig_p->flags |= KPROBE_FLAG_DISABLED;
}
}
@@ -2049,10 +2157,11 @@ static void __kprobes report_probe(struct seq_file *pi, struct kprobe *p,
if (!pp)
pp = p;
- seq_printf(pi, "%s%s%s\n",
+ seq_printf(pi, "%s%s%s%s\n",
(kprobe_gone(p) ? "[GONE]" : ""),
((kprobe_disabled(p) && !kprobe_gone(p)) ? "[DISABLED]" : ""),
- (kprobe_optimized(pp) ? "[OPTIMIZED]" : ""));
+ (kprobe_optimized(pp) ? "[OPTIMIZED]" : ""),
+ (kprobe_ftrace(pp) ? "[FTRACE]" : ""));
}
static void __kprobes *kprobe_seq_start(struct seq_file *f, loff_t *pos)
@@ -2131,14 +2240,12 @@ static void __kprobes arm_all_kprobes(void)
goto already_enabled;
/* Arming kprobes doesn't optimize kprobe itself */
- mutex_lock(&text_mutex);
for (i = 0; i < KPROBE_TABLE_SIZE; i++) {
head = &kprobe_table[i];
hlist_for_each_entry_rcu(p, node, head, hlist)
if (!kprobe_disabled(p))
- __arm_kprobe(p);
+ arm_kprobe(p);
}
- mutex_unlock(&text_mutex);
kprobes_all_disarmed = false;
printk(KERN_INFO "Kprobes globally enabled\n");
@@ -2166,15 +2273,13 @@ static void __kprobes disarm_all_kprobes(void)
kprobes_all_disarmed = true;
printk(KERN_INFO "Kprobes globally disabled\n");
- mutex_lock(&text_mutex);
for (i = 0; i < KPROBE_TABLE_SIZE; i++) {
head = &kprobe_table[i];
hlist_for_each_entry_rcu(p, node, head, hlist) {
if (!arch_trampoline_kprobe(p) && !kprobe_disabled(p))
- __disarm_kprobe(p, false);
+ disarm_kprobe(p, false);
}
}
- mutex_unlock(&text_mutex);
mutex_unlock(&kprobe_mutex);
/* Wait for disarming all kprobes by optimizer */
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index 8c4c07071cc5..4cea4f41c1d9 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -49,6 +49,11 @@ config HAVE_SYSCALL_TRACEPOINTS
help
See Documentation/trace/ftrace-design.txt
+config HAVE_FENTRY
+ bool
+ help
+ Arch supports the gcc options -pg with -mfentry
+
config HAVE_C_RECORDMCOUNT
bool
help
@@ -57,8 +62,12 @@ config HAVE_C_RECORDMCOUNT
config TRACER_MAX_TRACE
bool
+config TRACE_CLOCK
+ bool
+
config RING_BUFFER
bool
+ select TRACE_CLOCK
config FTRACE_NMI_ENTER
bool
@@ -109,6 +118,7 @@ config TRACING
select NOP_TRACER
select BINARY_PRINTF
select EVENT_TRACING
+ select TRACE_CLOCK
config GENERIC_TRACER
bool
diff --git a/kernel/trace/Makefile b/kernel/trace/Makefile
index b831087c8200..d7e2068e4b71 100644
--- a/kernel/trace/Makefile
+++ b/kernel/trace/Makefile
@@ -5,10 +5,12 @@ ifdef CONFIG_FUNCTION_TRACER
ORIG_CFLAGS := $(KBUILD_CFLAGS)
KBUILD_CFLAGS = $(subst -pg,,$(ORIG_CFLAGS))
+ifdef CONFIG_FTRACE_SELFTEST
# selftest needs instrumentation
CFLAGS_trace_selftest_dynamic.o = -pg
obj-y += trace_selftest_dynamic.o
endif
+endif
# If unlikely tracing is enabled, do not trace these files
ifdef CONFIG_TRACING_BRANCHES
@@ -17,11 +19,7 @@ endif
CFLAGS_trace_events_filter.o := -I$(src)
-#
-# Make the trace clocks available generally: it's infrastructure
-# relied on by ptrace for example:
-#
-obj-y += trace_clock.o
+obj-$(CONFIG_TRACE_CLOCK) += trace_clock.o
obj-$(CONFIG_FUNCTION_TRACER) += libftrace.o
obj-$(CONFIG_RING_BUFFER) += ring_buffer.o
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index b4f20fba09fc..9dcf15d38380 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -64,12 +64,20 @@
#define FL_GLOBAL_CONTROL_MASK (FTRACE_OPS_FL_GLOBAL | FTRACE_OPS_FL_CONTROL)
+static struct ftrace_ops ftrace_list_end __read_mostly = {
+ .func = ftrace_stub,
+ .flags = FTRACE_OPS_FL_RECURSION_SAFE,
+};
+
/* ftrace_enabled is a method to turn ftrace on or off */
int ftrace_enabled __read_mostly;
static int last_ftrace_enabled;
/* Quick disabling of function tracer. */
-int function_trace_stop;
+int function_trace_stop __read_mostly;
+
+/* Current function tracing op */
+struct ftrace_ops *function_trace_op __read_mostly = &ftrace_list_end;
/* List for set_ftrace_pid's pids. */
LIST_HEAD(ftrace_pids);
@@ -86,22 +94,43 @@ static int ftrace_disabled __read_mostly;
static DEFINE_MUTEX(ftrace_lock);
-static struct ftrace_ops ftrace_list_end __read_mostly = {
- .func = ftrace_stub,
-};
-
static struct ftrace_ops *ftrace_global_list __read_mostly = &ftrace_list_end;
static struct ftrace_ops *ftrace_control_list __read_mostly = &ftrace_list_end;
static struct ftrace_ops *ftrace_ops_list __read_mostly = &ftrace_list_end;
ftrace_func_t ftrace_trace_function __read_mostly = ftrace_stub;
-static ftrace_func_t __ftrace_trace_function_delay __read_mostly = ftrace_stub;
-ftrace_func_t __ftrace_trace_function __read_mostly = ftrace_stub;
ftrace_func_t ftrace_pid_function __read_mostly = ftrace_stub;
static struct ftrace_ops global_ops;
static struct ftrace_ops control_ops;
-static void
-ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip);
+#if ARCH_SUPPORTS_FTRACE_OPS
+static void ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip,
+ struct ftrace_ops *op, struct pt_regs *regs);
+#else
+/* See comment below, where ftrace_ops_list_func is defined */
+static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip);
+#define ftrace_ops_list_func ((ftrace_func_t)ftrace_ops_no_ops)
+#endif
+
+/**
+ * ftrace_nr_registered_ops - return number of ops registered
+ *
+ * Returns the number of ftrace_ops registered and tracing functions
+ */
+int ftrace_nr_registered_ops(void)
+{
+ struct ftrace_ops *ops;
+ int cnt = 0;
+
+ mutex_lock(&ftrace_lock);
+
+ for (ops = ftrace_ops_list;
+ ops != &ftrace_list_end; ops = ops->next)
+ cnt++;
+
+ mutex_unlock(&ftrace_lock);
+
+ return cnt;
+}
/*
* Traverse the ftrace_global_list, invoking all entries. The reason that we
@@ -112,29 +141,29 @@ ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip);
*
* Silly Alpha and silly pointer-speculation compiler optimizations!
*/
-static void ftrace_global_list_func(unsigned long ip,
- unsigned long parent_ip)
+static void
+ftrace_global_list_func(unsigned long ip, unsigned long parent_ip,
+ struct ftrace_ops *op, struct pt_regs *regs)
{
- struct ftrace_ops *op;
-
if (unlikely(trace_recursion_test(TRACE_GLOBAL_BIT)))
return;
trace_recursion_set(TRACE_GLOBAL_BIT);
op = rcu_dereference_raw(ftrace_global_list); /*see above*/
while (op != &ftrace_list_end) {
- op->func(ip, parent_ip);
+ op->func(ip, parent_ip, op, regs);
op = rcu_dereference_raw(op->next); /*see above*/
};
trace_recursion_clear(TRACE_GLOBAL_BIT);
}
-static void ftrace_pid_func(unsigned long ip, unsigned long parent_ip)
+static void ftrace_pid_func(unsigned long ip, unsigned long parent_ip,
+ struct ftrace_ops *op, struct pt_regs *regs)
{
if (!test_tsk_trace_trace(current))
return;
- ftrace_pid_function(ip, parent_ip);
+ ftrace_pid_function(ip, parent_ip, op, regs);
}
static void set_ftrace_pid_function(ftrace_func_t func)
@@ -153,25 +182,9 @@ static void set_ftrace_pid_function(ftrace_func_t func)
void clear_ftrace_function(void)
{
ftrace_trace_function = ftrace_stub;
- __ftrace_trace_function = ftrace_stub;
- __ftrace_trace_function_delay = ftrace_stub;
ftrace_pid_function = ftrace_stub;
}
-#ifndef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST
-/*
- * For those archs that do not test ftrace_trace_stop in their
- * mcount call site, we need to do it from C.
- */
-static void ftrace_test_stop_func(unsigned long ip, unsigned long parent_ip)
-{
- if (function_trace_stop)
- return;
-
- __ftrace_trace_function(ip, parent_ip);
-}
-#endif
-
static void control_ops_disable_all(struct ftrace_ops *ops)
{
int cpu;
@@ -230,28 +243,27 @@ static void update_ftrace_function(void)
/*
* If we are at the end of the list and this ops is
- * not dynamic, then have the mcount trampoline call
- * the function directly
+ * recursion safe and not dynamic and the arch supports passing ops,
+ * then have the mcount trampoline call the function directly.
*/
if (ftrace_ops_list == &ftrace_list_end ||
(ftrace_ops_list->next == &ftrace_list_end &&
- !(ftrace_ops_list->flags & FTRACE_OPS_FL_DYNAMIC)))
+ !(ftrace_ops_list->flags & FTRACE_OPS_FL_DYNAMIC) &&
+ (ftrace_ops_list->flags & FTRACE_OPS_FL_RECURSION_SAFE) &&
+ !FTRACE_FORCE_LIST_FUNC)) {
+ /* Set the ftrace_ops that the arch callback uses */
+ if (ftrace_ops_list == &global_ops)
+ function_trace_op = ftrace_global_list;
+ else
+ function_trace_op = ftrace_ops_list;
func = ftrace_ops_list->func;
- else
+ } else {
+ /* Just use the default ftrace_ops */
+ function_trace_op = &ftrace_list_end;
func = ftrace_ops_list_func;
+ }
-#ifdef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST
ftrace_trace_function = func;
-#else
-#ifdef CONFIG_DYNAMIC_FTRACE
- /* do not update till all functions have been modified */
- __ftrace_trace_function_delay = func;
-#else
- __ftrace_trace_function = func;
-#endif
- ftrace_trace_function =
- (func == ftrace_stub) ? func : ftrace_test_stop_func;
-#endif
}
static void add_ftrace_ops(struct ftrace_ops **list, struct ftrace_ops *ops)
@@ -325,6 +337,20 @@ static int __register_ftrace_function(struct ftrace_ops *ops)
if ((ops->flags & FL_GLOBAL_CONTROL_MASK) == FL_GLOBAL_CONTROL_MASK)
return -EINVAL;
+#ifndef ARCH_SUPPORTS_FTRACE_SAVE_REGS
+ /*
+ * If the ftrace_ops specifies SAVE_REGS, then it only can be used
+ * if the arch supports it, or SAVE_REGS_IF_SUPPORTED is also set.
+ * Setting SAVE_REGS_IF_SUPPORTED makes SAVE_REGS irrelevant.
+ */
+ if (ops->flags & FTRACE_OPS_FL_SAVE_REGS &&
+ !(ops->flags & FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED))
+ return -EINVAL;
+
+ if (ops->flags & FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED)
+ ops->flags |= FTRACE_OPS_FL_SAVE_REGS;
+#endif
+
if (!core_kernel_data((unsigned long)ops))
ops->flags |= FTRACE_OPS_FL_DYNAMIC;
@@ -773,7 +799,8 @@ ftrace_profile_alloc(struct ftrace_profile_stat *stat, unsigned long ip)
}
static void
-function_profile_call(unsigned long ip, unsigned long parent_ip)
+function_profile_call(unsigned long ip, unsigned long parent_ip,
+ struct ftrace_ops *ops, struct pt_regs *regs)
{
struct ftrace_profile_stat *stat;
struct ftrace_profile *rec;
@@ -803,7 +830,7 @@ function_profile_call(unsigned long ip, unsigned long parent_ip)
#ifdef CONFIG_FUNCTION_GRAPH_TRACER
static int profile_graph_entry(struct ftrace_graph_ent *trace)
{
- function_profile_call(trace->func, 0);
+ function_profile_call(trace->func, 0, NULL, NULL);
return 1;
}
@@ -863,6 +890,7 @@ static void unregister_ftrace_profiler(void)
#else
static struct ftrace_ops ftrace_profile_ops __read_mostly = {
.func = function_profile_call,
+ .flags = FTRACE_OPS_FL_RECURSION_SAFE,
};
static int register_ftrace_profiler(void)
@@ -1045,6 +1073,7 @@ static struct ftrace_ops global_ops = {
.func = ftrace_stub,
.notrace_hash = EMPTY_HASH,
.filter_hash = EMPTY_HASH,
+ .flags = FTRACE_OPS_FL_RECURSION_SAFE,
};
static DEFINE_MUTEX(ftrace_regex_lock);
@@ -1525,6 +1554,12 @@ static void __ftrace_hash_rec_update(struct ftrace_ops *ops,
rec->flags++;
if (FTRACE_WARN_ON((rec->flags & ~FTRACE_FL_MASK) == FTRACE_REF_MAX))
return;
+ /*
+ * If any ops wants regs saved for this function
+ * then all ops will get saved regs.
+ */
+ if (ops->flags & FTRACE_OPS_FL_SAVE_REGS)
+ rec->flags |= FTRACE_FL_REGS;
} else {
if (FTRACE_WARN_ON((rec->flags & ~FTRACE_FL_MASK) == 0))
return;
@@ -1616,18 +1651,59 @@ static int ftrace_check_record(struct dyn_ftrace *rec, int enable, int update)
if (enable && (rec->flags & ~FTRACE_FL_MASK))
flag = FTRACE_FL_ENABLED;
+ /*
+ * If enabling and the REGS flag does not match the REGS_EN, then
+ * do not ignore this record. Set flags to fail the compare against
+ * ENABLED.
+ */
+ if (flag &&
+ (!(rec->flags & FTRACE_FL_REGS) != !(rec->flags & FTRACE_FL_REGS_EN)))
+ flag |= FTRACE_FL_REGS;
+
/* If the state of this record hasn't changed, then do nothing */
if ((rec->flags & FTRACE_FL_ENABLED) == flag)
return FTRACE_UPDATE_IGNORE;
if (flag) {
- if (update)
+ /* Save off if rec is being enabled (for return value) */
+ flag ^= rec->flags & FTRACE_FL_ENABLED;
+
+ if (update) {
rec->flags |= FTRACE_FL_ENABLED;
- return FTRACE_UPDATE_MAKE_CALL;
+ if (flag & FTRACE_FL_REGS) {
+ if (rec->flags & FTRACE_FL_REGS)
+ rec->flags |= FTRACE_FL_REGS_EN;
+ else
+ rec->flags &= ~FTRACE_FL_REGS_EN;
+ }
+ }
+
+ /*
+ * If this record is being updated from a nop, then
+ * return UPDATE_MAKE_CALL.
+ * Otherwise, if the EN flag is set, then return
+ * UPDATE_MODIFY_CALL_REGS to tell the caller to convert
+ * from the non-save regs, to a save regs function.
+ * Otherwise,
+ * return UPDATE_MODIFY_CALL to tell the caller to convert
+ * from the save regs, to a non-save regs function.
+ */
+ if (flag & FTRACE_FL_ENABLED)
+ return FTRACE_UPDATE_MAKE_CALL;
+ else if (rec->flags & FTRACE_FL_REGS_EN)
+ return FTRACE_UPDATE_MODIFY_CALL_REGS;
+ else
+ return FTRACE_UPDATE_MODIFY_CALL;
}
- if (update)
- rec->flags &= ~FTRACE_FL_ENABLED;
+ if (update) {
+ /* If there's no more users, clear all flags */
+ if (!(rec->flags & ~FTRACE_FL_MASK))
+ rec->flags = 0;
+ else
+ /* Just disable the record (keep REGS state) */
+ rec->flags &= ~FTRACE_FL_ENABLED;
+ }
return FTRACE_UPDATE_MAKE_NOP;
}
@@ -1662,13 +1738,17 @@ int ftrace_test_record(struct dyn_ftrace *rec, int enable)
static int
__ftrace_replace_code(struct dyn_ftrace *rec, int enable)
{
+ unsigned long ftrace_old_addr;
unsigned long ftrace_addr;
int ret;
- ftrace_addr = (unsigned long)FTRACE_ADDR;
-
ret = ftrace_update_record(rec, enable);
+ if (rec->flags & FTRACE_FL_REGS)
+ ftrace_addr = (unsigned long)FTRACE_REGS_ADDR;
+ else
+ ftrace_addr = (unsigned long)FTRACE_ADDR;
+
switch (ret) {
case FTRACE_UPDATE_IGNORE:
return 0;
@@ -1678,6 +1758,15 @@ __ftrace_replace_code(struct dyn_ftrace *rec, int enable)
case FTRACE_UPDATE_MAKE_NOP:
return ftrace_make_nop(NULL, rec, ftrace_addr);
+
+ case FTRACE_UPDATE_MODIFY_CALL_REGS:
+ case FTRACE_UPDATE_MODIFY_CALL:
+ if (rec->flags & FTRACE_FL_REGS)
+ ftrace_old_addr = (unsigned long)FTRACE_ADDR;
+ else
+ ftrace_old_addr = (unsigned long)FTRACE_REGS_ADDR;
+
+ return ftrace_modify_call(rec, ftrace_old_addr, ftrace_addr);
}
return -1; /* unknow ftrace bug */
@@ -1882,16 +1971,6 @@ static void ftrace_run_update_code(int command)
*/
arch_ftrace_update_code(command);
-#ifndef CONFIG_HAVE_FUNCTION_TRACE_MCOUNT_TEST
- /*
- * For archs that call ftrace_test_stop_func(), we must
- * wait till after we update all the function callers
- * before we update the callback. This keeps different
- * ops that record different functions from corrupting
- * each other.
- */
- __ftrace_trace_function = __ftrace_trace_function_delay;
-#endif
function_trace_stop--;
ret = ftrace_arch_code_modify_post_process();
@@ -2441,8 +2520,9 @@ static int t_show(struct seq_file *m, void *v)
seq_printf(m, "%ps", (void *)rec->ip);
if (iter->flags & FTRACE_ITER_ENABLED)
- seq_printf(m, " (%ld)",
- rec->flags & ~FTRACE_FL_MASK);
+ seq_printf(m, " (%ld)%s",
+ rec->flags & ~FTRACE_FL_MASK,
+ rec->flags & FTRACE_FL_REGS ? " R" : "");
seq_printf(m, "\n");
return 0;
@@ -2790,8 +2870,8 @@ static int __init ftrace_mod_cmd_init(void)
}
device_initcall(ftrace_mod_cmd_init);
-static void
-function_trace_probe_call(unsigned long ip, unsigned long parent_ip)
+static void function_trace_probe_call(unsigned long ip, unsigned long parent_ip,
+ struct ftrace_ops *op, struct pt_regs *pt_regs)
{
struct ftrace_func_probe *entry;
struct hlist_head *hhd;
@@ -3162,8 +3242,27 @@ ftrace_notrace_write(struct file *file, const char __user *ubuf,
}
static int
-ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len,
- int reset, int enable)
+ftrace_match_addr(struct ftrace_hash *hash, unsigned long ip, int remove)
+{
+ struct ftrace_func_entry *entry;
+
+ if (!ftrace_location(ip))
+ return -EINVAL;
+
+ if (remove) {
+ entry = ftrace_lookup_ip(hash, ip);
+ if (!entry)
+ return -ENOENT;
+ free_hash_entry(hash, entry);
+ return 0;
+ }
+
+ return add_hash_entry(hash, ip);
+}
+
+static int
+ftrace_set_hash(struct ftrace_ops *ops, unsigned char *buf, int len,
+ unsigned long ip, int remove, int reset, int enable)
{
struct ftrace_hash **orig_hash;
struct ftrace_hash *hash;
@@ -3192,6 +3291,11 @@ ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len,
ret = -EINVAL;
goto out_regex_unlock;
}
+ if (ip) {
+ ret = ftrace_match_addr(hash, ip, remove);
+ if (ret < 0)
+ goto out_regex_unlock;
+ }
mutex_lock(&ftrace_lock);
ret = ftrace_hash_move(ops, enable, orig_hash, hash);
@@ -3208,6 +3312,37 @@ ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len,
return ret;
}
+static int
+ftrace_set_addr(struct ftrace_ops *ops, unsigned long ip, int remove,
+ int reset, int enable)
+{
+ return ftrace_set_hash(ops, 0, 0, ip, remove, reset, enable);
+}
+
+/**
+ * ftrace_set_filter_ip - set a function to filter on in ftrace by address
+ * @ops - the ops to set the filter with
+ * @ip - the address to add to or remove from the filter.
+ * @remove - non zero to remove the ip from the filter
+ * @reset - non zero to reset all filters before applying this filter.
+ *
+ * Filters denote which functions should be enabled when tracing is enabled
+ * If @ip is NULL, it failes to update filter.
+ */
+int ftrace_set_filter_ip(struct ftrace_ops *ops, unsigned long ip,
+ int remove, int reset)
+{
+ return ftrace_set_addr(ops, ip, remove, reset, 1);
+}
+EXPORT_SYMBOL_GPL(ftrace_set_filter_ip);
+
+static int
+ftrace_set_regex(struct ftrace_ops *ops, unsigned char *buf, int len,
+ int reset, int enable)
+{
+ return ftrace_set_hash(ops, buf, len, 0, 0, reset, enable);
+}
+
/**
* ftrace_set_filter - set a function to filter on in ftrace
* @ops - the ops to set the filter with
@@ -3912,6 +4047,7 @@ void __init ftrace_init(void)
static struct ftrace_ops global_ops = {
.func = ftrace_stub,
+ .flags = FTRACE_OPS_FL_RECURSION_SAFE,
};
static int __init ftrace_nodyn_init(void)
@@ -3942,10 +4078,9 @@ ftrace_ops_test(struct ftrace_ops *ops, unsigned long ip)
#endif /* CONFIG_DYNAMIC_FTRACE */
static void
-ftrace_ops_control_func(unsigned long ip, unsigned long parent_ip)
+ftrace_ops_control_func(unsigned long ip, unsigned long parent_ip,
+ struct ftrace_ops *op, struct pt_regs *regs)
{
- struct ftrace_ops *op;
-
if (unlikely(trace_recursion_test(TRACE_CONTROL_BIT)))
return;
@@ -3959,7 +4094,7 @@ ftrace_ops_control_func(unsigned long ip, unsigned long parent_ip)
while (op != &ftrace_list_end) {
if (!ftrace_function_local_disabled(op) &&
ftrace_ops_test(op, ip))
- op->func(ip, parent_ip);
+ op->func(ip, parent_ip, op, regs);
op = rcu_dereference_raw(op->next);
};
@@ -3969,13 +4104,18 @@ ftrace_ops_control_func(unsigned long ip, unsigned long parent_ip)
static struct ftrace_ops control_ops = {
.func = ftrace_ops_control_func,
+ .flags = FTRACE_OPS_FL_RECURSION_SAFE,
};
-static void
-ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip)
+static inline void
+__ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip,
+ struct ftrace_ops *ignored, struct pt_regs *regs)
{
struct ftrace_ops *op;
+ if (function_trace_stop)
+ return;
+
if (unlikely(trace_recursion_test(TRACE_INTERNAL_BIT)))
return;
@@ -3988,13 +4128,39 @@ ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip)
op = rcu_dereference_raw(ftrace_ops_list);
while (op != &ftrace_list_end) {
if (ftrace_ops_test(op, ip))
- op->func(ip, parent_ip);
+ op->func(ip, parent_ip, op, regs);
op = rcu_dereference_raw(op->next);
};
preempt_enable_notrace();
trace_recursion_clear(TRACE_INTERNAL_BIT);
}
+/*
+ * Some archs only support passing ip and parent_ip. Even though
+ * the list function ignores the op parameter, we do not want any
+ * C side effects, where a function is called without the caller
+ * sending a third parameter.
+ * Archs are to support both the regs and ftrace_ops at the same time.
+ * If they support ftrace_ops, it is assumed they support regs.
+ * If call backs want to use regs, they must either check for regs
+ * being NULL, or ARCH_SUPPORTS_FTRACE_SAVE_REGS.
+ * Note, ARCH_SUPPORT_SAVE_REGS expects a full regs to be saved.
+ * An architecture can pass partial regs with ftrace_ops and still
+ * set the ARCH_SUPPORT_FTARCE_OPS.
+ */
+#if ARCH_SUPPORTS_FTRACE_OPS
+static void ftrace_ops_list_func(unsigned long ip, unsigned long parent_ip,
+ struct ftrace_ops *op, struct pt_regs *regs)
+{
+ __ftrace_ops_list_func(ip, parent_ip, NULL, regs);
+}
+#else
+static void ftrace_ops_no_ops(unsigned long ip, unsigned long parent_ip)
+{
+ __ftrace_ops_list_func(ip, parent_ip, NULL, NULL);
+}
+#endif
+
static void clear_ftrace_swapper(void)
{
struct task_struct *p;
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 49491fa7daa2..b32ed0e385a5 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -2816,7 +2816,7 @@ EXPORT_SYMBOL_GPL(ring_buffer_record_enable);
* to the buffer after this will fail and return NULL.
*
* This is different than ring_buffer_record_disable() as
- * it works like an on/off switch, where as the disable() verison
+ * it works like an on/off switch, where as the disable() version
* must be paired with a enable().
*/
void ring_buffer_record_off(struct ring_buffer *buffer)
@@ -2839,7 +2839,7 @@ EXPORT_SYMBOL_GPL(ring_buffer_record_off);
* ring_buffer_record_off().
*
* This is different than ring_buffer_record_enable() as
- * it works like an on/off switch, where as the enable() verison
+ * it works like an on/off switch, where as the enable() version
* must be paired with a disable().
*/
void ring_buffer_record_on(struct ring_buffer *buffer)
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 5c38c81496ce..1ec5c1dab629 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -328,7 +328,7 @@ static DECLARE_WAIT_QUEUE_HEAD(trace_wait);
unsigned long trace_flags = TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK |
TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | TRACE_ITER_SLEEP_TIME |
TRACE_ITER_GRAPH_TIME | TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE |
- TRACE_ITER_IRQ_INFO;
+ TRACE_ITER_IRQ_INFO | TRACE_ITER_MARKERS;
static int trace_stop_count;
static DEFINE_RAW_SPINLOCK(tracing_start_lock);
@@ -426,15 +426,15 @@ __setup("trace_buf_size=", set_buf_size);
static int __init set_tracing_thresh(char *str)
{
- unsigned long threshhold;
+ unsigned long threshold;
int ret;
if (!str)
return 0;
- ret = strict_strtoul(str, 0, &threshhold);
+ ret = strict_strtoul(str, 0, &threshold);
if (ret < 0)
return 0;
- tracing_thresh = threshhold * 1000;
+ tracing_thresh = threshold * 1000;
return 1;
}
__setup("tracing_thresh=", set_tracing_thresh);
@@ -470,6 +470,7 @@ static const char *trace_options[] = {
"overwrite",
"disable_on_free",
"irq-info",
+ "markers",
NULL
};
@@ -3886,6 +3887,9 @@ tracing_mark_write(struct file *filp, const char __user *ubuf,
if (tracing_disabled)
return -EINVAL;
+ if (!(trace_flags & TRACE_ITER_MARKERS))
+ return -EINVAL;
+
if (cnt > TRACE_BUF_SIZE)
cnt = TRACE_BUF_SIZE;
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 55e1f7f0db12..63a2da0b9a6e 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -472,11 +472,11 @@ extern void trace_find_cmdline(int pid, char comm[]);
#ifdef CONFIG_DYNAMIC_FTRACE
extern unsigned long ftrace_update_tot_cnt;
+#endif
#define DYN_FTRACE_TEST_NAME trace_selftest_dynamic_test_func
extern int DYN_FTRACE_TEST_NAME(void);
#define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2
extern int DYN_FTRACE_TEST_NAME2(void);
-#endif
extern int ring_buffer_expanded;
extern bool tracing_selftest_disabled;
@@ -680,6 +680,7 @@ enum trace_iterator_flags {
TRACE_ITER_OVERWRITE = 0x200000,
TRACE_ITER_STOP_ON_FREE = 0x400000,
TRACE_ITER_IRQ_INFO = 0x800000,
+ TRACE_ITER_MARKERS = 0x1000000,
};
/*
diff --git a/kernel/trace/trace_event_perf.c b/kernel/trace/trace_event_perf.c
index 8a6d2ee2086c..84b1e045faba 100644
--- a/kernel/trace/trace_event_perf.c
+++ b/kernel/trace/trace_event_perf.c
@@ -258,7 +258,8 @@ EXPORT_SYMBOL_GPL(perf_trace_buf_prepare);
#ifdef CONFIG_FUNCTION_TRACER
static void
-perf_ftrace_function_call(unsigned long ip, unsigned long parent_ip)
+perf_ftrace_function_call(unsigned long ip, unsigned long parent_ip,
+ struct ftrace_ops *ops, struct pt_regs *pt_regs)
{
struct ftrace_entry *entry;
struct hlist_head *head;
diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c
index 29111da1d100..d608d09d08c0 100644
--- a/kernel/trace/trace_events.c
+++ b/kernel/trace/trace_events.c
@@ -1199,6 +1199,31 @@ event_create_dir(struct ftrace_event_call *call, struct dentry *d_events,
return 0;
}
+static void event_remove(struct ftrace_event_call *call)
+{
+ ftrace_event_enable_disable(call, 0);
+ if (call->event.funcs)
+ __unregister_ftrace_event(&call->event);
+ list_del(&call->list);
+}
+
+static int event_init(struct ftrace_event_call *call)
+{
+ int ret = 0;
+
+ if (WARN_ON(!call->name))
+ return -EINVAL;
+
+ if (call->class->raw_init) {
+ ret = call->class->raw_init(call);
+ if (ret < 0 && ret != -ENOSYS)
+ pr_warn("Could not initialize trace events/%s\n",
+ call->name);
+ }
+
+ return ret;
+}
+
static int
__trace_add_event_call(struct ftrace_event_call *call, struct module *mod,
const struct file_operations *id,
@@ -1209,19 +1234,9 @@ __trace_add_event_call(struct ftrace_event_call *call, struct module *mod,
struct dentry *d_events;
int ret;
- /* The linker may leave blanks */
- if (!call->name)
- return -EINVAL;
-
- if (call->class->raw_init) {
- ret = call->class->raw_init(call);
- if (ret < 0) {
- if (ret != -ENOSYS)
- pr_warning("Could not initialize trace events/%s\n",
- call->name);
- return ret;
- }
- }
+ ret = event_init(call);
+ if (ret < 0)
+ return ret;
d_events = event_trace_events_dir();
if (!d_events)
@@ -1272,13 +1287,10 @@ static void remove_subsystem_dir(const char *name)
*/
static void __trace_remove_event_call(struct ftrace_event_call *call)
{
- ftrace_event_enable_disable(call, 0);
- if (call->event.funcs)
- __unregister_ftrace_event(&call->event);
- debugfs_remove_recursive(call->dir);
- list_del(&call->list);
+ event_remove(call);
trace_destroy_fields(call);
destroy_preds(call);
+ debugfs_remove_recursive(call->dir);
remove_subsystem_dir(call->class->system);
}
@@ -1450,15 +1462,43 @@ static __init int setup_trace_event(char *str)
}
__setup("trace_event=", setup_trace_event);
+static __init int event_trace_enable(void)
+{
+ struct ftrace_event_call **iter, *call;
+ char *buf = bootup_event_buf;
+ char *token;
+ int ret;
+
+ for_each_event(iter, __start_ftrace_events, __stop_ftrace_events) {
+
+ call = *iter;
+ ret = event_init(call);
+ if (!ret)
+ list_add(&call->list, &ftrace_events);
+ }
+
+ while (true) {
+ token = strsep(&buf, ",");
+
+ if (!token)
+ break;
+ if (!*token)
+ continue;
+
+ ret = ftrace_set_clr_event(token, 1);
+ if (ret)
+ pr_warn("Failed to enable trace event: %s\n", token);
+ }
+ return 0;
+}
+
static __init int event_trace_init(void)
{
- struct ftrace_event_call **call;
+ struct ftrace_event_call *call;
struct dentry *d_tracer;
struct dentry *entry;
struct dentry *d_events;
int ret;
- char *buf = bootup_event_buf;
- char *token;
d_tracer = tracing_init_dentry();
if (!d_tracer)
@@ -1497,24 +1537,19 @@ static __init int event_trace_init(void)
if (trace_define_common_fields())
pr_warning("tracing: Failed to allocate common fields");
- for_each_event(call, __start_ftrace_events, __stop_ftrace_events) {
- __trace_add_event_call(*call, NULL, &ftrace_event_id_fops,
+ /*
+ * Early initialization already enabled ftrace event.
+ * Now it's only necessary to create the event directory.
+ */
+ list_for_each_entry(call, &ftrace_events, list) {
+
+ ret = event_create_dir(call, d_events,
+ &ftrace_event_id_fops,
&ftrace_enable_fops,
&ftrace_event_filter_fops,
&ftrace_event_format_fops);
- }
-
- while (true) {
- token = strsep(&buf, ",");
-
- if (!token)
- break;
- if (!*token)
- continue;
-
- ret = ftrace_set_clr_event(token, 1);
- if (ret)
- pr_warning("Failed to enable trace event: %s\n", token);
+ if (ret < 0)
+ event_remove(call);
}
ret = register_module_notifier(&trace_module_nb);
@@ -1523,6 +1558,7 @@ static __init int event_trace_init(void)
return 0;
}
+core_initcall(event_trace_enable);
fs_initcall(event_trace_init);
#ifdef CONFIG_FTRACE_STARTUP_TEST
@@ -1646,9 +1682,11 @@ static __init void event_trace_self_tests(void)
event_test_stuff();
ret = __ftrace_set_clr_event(NULL, system->name, NULL, 0);
- if (WARN_ON_ONCE(ret))
+ if (WARN_ON_ONCE(ret)) {
pr_warning("error disabling system %s\n",
system->name);
+ continue;
+ }
pr_cont("OK\n");
}
@@ -1681,7 +1719,8 @@ static __init void event_trace_self_tests(void)
static DEFINE_PER_CPU(atomic_t, ftrace_test_event_disable);
static void
-function_test_events_call(unsigned long ip, unsigned long parent_ip)
+function_test_events_call(unsigned long ip, unsigned long parent_ip,
+ struct ftrace_ops *op, struct pt_regs *pt_regs)
{
struct ring_buffer_event *event;
struct ring_buffer *buffer;
@@ -1720,6 +1759,7 @@ function_test_events_call(unsigned long ip, unsigned long parent_ip)
static struct ftrace_ops trace_ops __initdata =
{
.func = function_test_events_call,
+ .flags = FTRACE_OPS_FL_RECURSION_SAFE,
};
static __init void event_trace_self_test_with_function(void)
diff --git a/kernel/trace/trace_events_filter.c b/kernel/trace/trace_events_filter.c
index 431dba8b7542..c154797a7ff7 100644
--- a/kernel/trace/trace_events_filter.c
+++ b/kernel/trace/trace_events_filter.c
@@ -2002,7 +2002,7 @@ static int ftrace_function_set_regexp(struct ftrace_ops *ops, int filter,
static int __ftrace_function_set_filter(int filter, char *buf, int len,
struct function_filter_data *data)
{
- int i, re_cnt, ret;
+ int i, re_cnt, ret = -EINVAL;
int *reset;
char **re;
diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c
index a426f410c060..483162a9f908 100644
--- a/kernel/trace/trace_functions.c
+++ b/kernel/trace/trace_functions.c
@@ -49,7 +49,8 @@ static void function_trace_start(struct trace_array *tr)
}
static void
-function_trace_call_preempt_only(unsigned long ip, unsigned long parent_ip)
+function_trace_call_preempt_only(unsigned long ip, unsigned long parent_ip,
+ struct ftrace_ops *op, struct pt_regs *pt_regs)
{
struct trace_array *tr = func_trace;
struct trace_array_cpu *data;
@@ -84,7 +85,9 @@ enum {
static struct tracer_flags func_flags;
static void
-function_trace_call(unsigned long ip, unsigned long parent_ip)
+function_trace_call(unsigned long ip, unsigned long parent_ip,
+ struct ftrace_ops *op, struct pt_regs *pt_regs)
+
{
struct trace_array *tr = func_trace;
struct trace_array_cpu *data;
@@ -121,7 +124,8 @@ function_trace_call(unsigned long ip, unsigned long parent_ip)
}
static void
-function_stack_trace_call(unsigned long ip, unsigned long parent_ip)
+function_stack_trace_call(unsigned long ip, unsigned long parent_ip,
+ struct ftrace_ops *op, struct pt_regs *pt_regs)
{
struct trace_array *tr = func_trace;
struct trace_array_cpu *data;
@@ -164,13 +168,13 @@ function_stack_trace_call(unsigned long ip, unsigned long parent_ip)
static struct ftrace_ops trace_ops __read_mostly =
{
.func = function_trace_call,
- .flags = FTRACE_OPS_FL_GLOBAL,
+ .flags = FTRACE_OPS_FL_GLOBAL | FTRACE_OPS_FL_RECURSION_SAFE,
};
static struct ftrace_ops trace_stack_ops __read_mostly =
{
.func = function_stack_trace_call,
- .flags = FTRACE_OPS_FL_GLOBAL,
+ .flags = FTRACE_OPS_FL_GLOBAL | FTRACE_OPS_FL_RECURSION_SAFE,
};
static struct tracer_opt func_opts[] = {
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index ce27c8ba8d31..99b4378393d5 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -143,7 +143,7 @@ ftrace_pop_return_trace(struct ftrace_graph_ret *trace, unsigned long *ret,
return;
}
-#ifdef CONFIG_HAVE_FUNCTION_GRAPH_FP_TEST
+#if defined(CONFIG_HAVE_FUNCTION_GRAPH_FP_TEST) && !defined(CC_USING_FENTRY)
/*
* The arch may choose to record the frame pointer used
* and check it here to make sure that it is what we expect it
@@ -154,6 +154,9 @@ ftrace_pop_return_trace(struct ftrace_graph_ret *trace, unsigned long *ret,
*
* Currently, x86_32 with optimize for size (-Os) makes the latest
* gcc do the above.
+ *
+ * Note, -mfentry does not use frame pointers, and this test
+ * is not needed if CC_USING_FENTRY is set.
*/
if (unlikely(current->ret_stack[index].fp != frame_pointer)) {
ftrace_graph_stop();
diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c
index 99d20e920368..d98ee8283b29 100644
--- a/kernel/trace/trace_irqsoff.c
+++ b/kernel/trace/trace_irqsoff.c
@@ -136,7 +136,8 @@ static int func_prolog_dec(struct trace_array *tr,
* irqsoff uses its own tracer function to keep the overhead down:
*/
static void
-irqsoff_tracer_call(unsigned long ip, unsigned long parent_ip)
+irqsoff_tracer_call(unsigned long ip, unsigned long parent_ip,
+ struct ftrace_ops *op, struct pt_regs *pt_regs)
{
struct trace_array *tr = irqsoff_trace;
struct trace_array_cpu *data;
@@ -153,7 +154,7 @@ irqsoff_tracer_call(unsigned long ip, unsigned long parent_ip)
static struct ftrace_ops trace_ops __read_mostly =
{
.func = irqsoff_tracer_call,
- .flags = FTRACE_OPS_FL_GLOBAL,
+ .flags = FTRACE_OPS_FL_GLOBAL | FTRACE_OPS_FL_RECURSION_SAFE,
};
#endif /* CONFIG_FUNCTION_TRACER */
diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c
index ff791ea48b57..02170c00c413 100644
--- a/kernel/trace/trace_sched_wakeup.c
+++ b/kernel/trace/trace_sched_wakeup.c
@@ -108,7 +108,8 @@ out_enable:
* wakeup uses its own tracer function to keep the overhead down:
*/
static void
-wakeup_tracer_call(unsigned long ip, unsigned long parent_ip)
+wakeup_tracer_call(unsigned long ip, unsigned long parent_ip,
+ struct ftrace_ops *op, struct pt_regs *pt_regs)
{
struct trace_array *tr = wakeup_trace;
struct trace_array_cpu *data;
@@ -129,7 +130,7 @@ wakeup_tracer_call(unsigned long ip, unsigned long parent_ip)
static struct ftrace_ops trace_ops __read_mostly =
{
.func = wakeup_tracer_call,
- .flags = FTRACE_OPS_FL_GLOBAL,
+ .flags = FTRACE_OPS_FL_GLOBAL | FTRACE_OPS_FL_RECURSION_SAFE,
};
#endif /* CONFIG_FUNCTION_TRACER */
diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c
index 288541f977fb..2c00a691a540 100644
--- a/kernel/trace/trace_selftest.c
+++ b/kernel/trace/trace_selftest.c
@@ -103,54 +103,67 @@ static inline void warn_failed_init_tracer(struct tracer *trace, int init_ret)
static int trace_selftest_test_probe1_cnt;
static void trace_selftest_test_probe1_func(unsigned long ip,
- unsigned long pip)
+ unsigned long pip,
+ struct ftrace_ops *op,
+ struct pt_regs *pt_regs)
{
trace_selftest_test_probe1_cnt++;
}
static int trace_selftest_test_probe2_cnt;
static void trace_selftest_test_probe2_func(unsigned long ip,
- unsigned long pip)
+ unsigned long pip,
+ struct ftrace_ops *op,
+ struct pt_regs *pt_regs)
{
trace_selftest_test_probe2_cnt++;
}
static int trace_selftest_test_probe3_cnt;
static void trace_selftest_test_probe3_func(unsigned long ip,
- unsigned long pip)
+ unsigned long pip,
+ struct ftrace_ops *op,
+ struct pt_regs *pt_regs)
{
trace_selftest_test_probe3_cnt++;
}
static int trace_selftest_test_global_cnt;
static void trace_selftest_test_global_func(unsigned long ip,
- unsigned long pip)
+ unsigned long pip,
+ struct ftrace_ops *op,
+ struct pt_regs *pt_regs)
{
trace_selftest_test_global_cnt++;
}
static int trace_selftest_test_dyn_cnt;
static void trace_selftest_test_dyn_func(unsigned long ip,
- unsigned long pip)
+ unsigned long pip,
+ struct ftrace_ops *op,
+ struct pt_regs *pt_regs)
{
trace_selftest_test_dyn_cnt++;
}
static struct ftrace_ops test_probe1 = {
.func = trace_selftest_test_probe1_func,
+ .flags = FTRACE_OPS_FL_RECURSION_SAFE,
};
static struct ftrace_ops test_probe2 = {
.func = trace_selftest_test_probe2_func,
+ .flags = FTRACE_OPS_FL_RECURSION_SAFE,
};
static struct ftrace_ops test_probe3 = {
.func = trace_selftest_test_probe3_func,
+ .flags = FTRACE_OPS_FL_RECURSION_SAFE,
};
static struct ftrace_ops test_global = {
- .func = trace_selftest_test_global_func,
- .flags = FTRACE_OPS_FL_GLOBAL,
+ .func = trace_selftest_test_global_func,
+ .flags = FTRACE_OPS_FL_GLOBAL | FTRACE_OPS_FL_RECURSION_SAFE,
};
static void print_counts(void)
@@ -393,10 +406,253 @@ int trace_selftest_startup_dynamic_tracing(struct tracer *trace,
return ret;
}
+
+static int trace_selftest_recursion_cnt;
+static void trace_selftest_test_recursion_func(unsigned long ip,
+ unsigned long pip,
+ struct ftrace_ops *op,
+ struct pt_regs *pt_regs)
+{
+ /*
+ * This function is registered without the recursion safe flag.
+ * The ftrace infrastructure should provide the recursion
+ * protection. If not, this will crash the kernel!
+ */
+ trace_selftest_recursion_cnt++;
+ DYN_FTRACE_TEST_NAME();
+}
+
+static void trace_selftest_test_recursion_safe_func(unsigned long ip,
+ unsigned long pip,
+ struct ftrace_ops *op,
+ struct pt_regs *pt_regs)
+{
+ /*
+ * We said we would provide our own recursion. By calling
+ * this function again, we should recurse back into this function
+ * and count again. But this only happens if the arch supports
+ * all of ftrace features and nothing else is using the function
+ * tracing utility.
+ */
+ if (trace_selftest_recursion_cnt++)
+ return;
+ DYN_FTRACE_TEST_NAME();
+}
+
+static struct ftrace_ops test_rec_probe = {
+ .func = trace_selftest_test_recursion_func,
+};
+
+static struct ftrace_ops test_recsafe_probe = {
+ .func = trace_selftest_test_recursion_safe_func,
+ .flags = FTRACE_OPS_FL_RECURSION_SAFE,
+};
+
+static int
+trace_selftest_function_recursion(void)
+{
+ int save_ftrace_enabled = ftrace_enabled;
+ int save_tracer_enabled = tracer_enabled;
+ char *func_name;
+ int len;
+ int ret;
+ int cnt;
+
+ /* The previous test PASSED */
+ pr_cont("PASSED\n");
+ pr_info("Testing ftrace recursion: ");
+
+
+ /* enable tracing, and record the filter function */
+ ftrace_enabled = 1;
+ tracer_enabled = 1;
+
+ /* Handle PPC64 '.' name */
+ func_name = "*" __stringify(DYN_FTRACE_TEST_NAME);
+ len = strlen(func_name);
+
+ ret = ftrace_set_filter(&test_rec_probe, func_name, len, 1);
+ if (ret) {
+ pr_cont("*Could not set filter* ");
+ goto out;
+ }
+
+ ret = register_ftrace_function(&test_rec_probe);
+ if (ret) {
+ pr_cont("*could not register callback* ");
+ goto out;
+ }
+
+ DYN_FTRACE_TEST_NAME();
+
+ unregister_ftrace_function(&test_rec_probe);
+
+ ret = -1;
+ if (trace_selftest_recursion_cnt != 1) {
+ pr_cont("*callback not called once (%d)* ",
+ trace_selftest_recursion_cnt);
+ goto out;
+ }
+
+ trace_selftest_recursion_cnt = 1;
+
+ pr_cont("PASSED\n");
+ pr_info("Testing ftrace recursion safe: ");
+
+ ret = ftrace_set_filter(&test_recsafe_probe, func_name, len, 1);
+ if (ret) {
+ pr_cont("*Could not set filter* ");
+ goto out;
+ }
+
+ ret = register_ftrace_function(&test_recsafe_probe);
+ if (ret) {
+ pr_cont("*could not register callback* ");
+ goto out;
+ }
+
+ DYN_FTRACE_TEST_NAME();
+
+ unregister_ftrace_function(&test_recsafe_probe);
+
+ /*
+ * If arch supports all ftrace features, and no other task
+ * was on the list, we should be fine.
+ */
+ if (!ftrace_nr_registered_ops() && !FTRACE_FORCE_LIST_FUNC)
+ cnt = 2; /* Should have recursed */
+ else
+ cnt = 1;
+
+ ret = -1;
+ if (trace_selftest_recursion_cnt != cnt) {
+ pr_cont("*callback not called expected %d times (%d)* ",
+ cnt, trace_selftest_recursion_cnt);
+ goto out;
+ }
+
+ ret = 0;
+out:
+ ftrace_enabled = save_ftrace_enabled;
+ tracer_enabled = save_tracer_enabled;
+
+ return ret;
+}
#else
# define trace_selftest_startup_dynamic_tracing(trace, tr, func) ({ 0; })
+# define trace_selftest_function_recursion() ({ 0; })
#endif /* CONFIG_DYNAMIC_FTRACE */
+static enum {
+ TRACE_SELFTEST_REGS_START,
+ TRACE_SELFTEST_REGS_FOUND,
+ TRACE_SELFTEST_REGS_NOT_FOUND,
+} trace_selftest_regs_stat;
+
+static void trace_selftest_test_regs_func(unsigned long ip,
+ unsigned long pip,
+ struct ftrace_ops *op,
+ struct pt_regs *pt_regs)
+{
+ if (pt_regs)
+ trace_selftest_regs_stat = TRACE_SELFTEST_REGS_FOUND;
+ else
+ trace_selftest_regs_stat = TRACE_SELFTEST_REGS_NOT_FOUND;
+}
+
+static struct ftrace_ops test_regs_probe = {
+ .func = trace_selftest_test_regs_func,
+ .flags = FTRACE_OPS_FL_RECURSION_SAFE | FTRACE_OPS_FL_SAVE_REGS,
+};
+
+static int
+trace_selftest_function_regs(void)
+{
+ int save_ftrace_enabled = ftrace_enabled;
+ int save_tracer_enabled = tracer_enabled;
+ char *func_name;
+ int len;
+ int ret;
+ int supported = 0;
+
+#ifdef ARCH_SUPPORTS_FTRACE_SAVE_REGS
+ supported = 1;
+#endif
+
+ /* The previous test PASSED */
+ pr_cont("PASSED\n");
+ pr_info("Testing ftrace regs%s: ",
+ !supported ? "(no arch support)" : "");
+
+ /* enable tracing, and record the filter function */
+ ftrace_enabled = 1;
+ tracer_enabled = 1;
+
+ /* Handle PPC64 '.' name */
+ func_name = "*" __stringify(DYN_FTRACE_TEST_NAME);
+ len = strlen(func_name);
+
+ ret = ftrace_set_filter(&test_regs_probe, func_name, len, 1);
+ /*
+ * If DYNAMIC_FTRACE is not set, then we just trace all functions.
+ * This test really doesn't care.
+ */
+ if (ret && ret != -ENODEV) {
+ pr_cont("*Could not set filter* ");
+ goto out;
+ }
+
+ ret = register_ftrace_function(&test_regs_probe);
+ /*
+ * Now if the arch does not support passing regs, then this should
+ * have failed.
+ */
+ if (!supported) {
+ if (!ret) {
+ pr_cont("*registered save-regs without arch support* ");
+ goto out;
+ }
+ test_regs_probe.flags |= FTRACE_OPS_FL_SAVE_REGS_IF_SUPPORTED;
+ ret = register_ftrace_function(&test_regs_probe);
+ }
+ if (ret) {
+ pr_cont("*could not register callback* ");
+ goto out;
+ }
+
+
+ DYN_FTRACE_TEST_NAME();
+
+ unregister_ftrace_function(&test_regs_probe);
+
+ ret = -1;
+
+ switch (trace_selftest_regs_stat) {
+ case TRACE_SELFTEST_REGS_START:
+ pr_cont("*callback never called* ");
+ goto out;
+
+ case TRACE_SELFTEST_REGS_FOUND:
+ if (supported)
+ break;
+ pr_cont("*callback received regs without arch support* ");
+ goto out;
+
+ case TRACE_SELFTEST_REGS_NOT_FOUND:
+ if (!supported)
+ break;
+ pr_cont("*callback received NULL regs* ");
+ goto out;
+ }
+
+ ret = 0;
+out:
+ ftrace_enabled = save_ftrace_enabled;
+ tracer_enabled = save_tracer_enabled;
+
+ return ret;
+}
+
/*
* Simple verification test of ftrace function tracer.
* Enable ftrace, sleep 1/10 second, and then read the trace
@@ -442,7 +698,14 @@ trace_selftest_startup_function(struct tracer *trace, struct trace_array *tr)
ret = trace_selftest_startup_dynamic_tracing(trace, tr,
DYN_FTRACE_TEST_NAME);
+ if (ret)
+ goto out;
+ ret = trace_selftest_function_recursion();
+ if (ret)
+ goto out;
+
+ ret = trace_selftest_function_regs();
out:
ftrace_enabled = save_ftrace_enabled;
tracer_enabled = save_tracer_enabled;
@@ -778,6 +1041,8 @@ static int trace_wakeup_test_thread(void *data)
set_current_state(TASK_INTERRUPTIBLE);
schedule();
+ complete(x);
+
/* we are awake, now wait to disappear */
while (!kthread_should_stop()) {
/*
@@ -821,24 +1086,21 @@ trace_selftest_startup_wakeup(struct tracer *trace, struct trace_array *tr)
/* reset the max latency */
tracing_max_latency = 0;
- /* sleep to let the RT thread sleep too */
- msleep(100);
+ while (p->on_rq) {
+ /*
+ * Sleep to make sure the RT thread is asleep too.
+ * On virtual machines we can't rely on timings,
+ * but we want to make sure this test still works.
+ */
+ msleep(100);
+ }
- /*
- * Yes this is slightly racy. It is possible that for some
- * strange reason that the RT thread we created, did not
- * call schedule for 100ms after doing the completion,
- * and we do a wakeup on a task that already is awake.
- * But that is extremely unlikely, and the worst thing that
- * happens in such a case, is that we disable tracing.
- * Honestly, if this race does happen something is horrible
- * wrong with the system.
- */
+ init_completion(&isrt);
wake_up_process(p);
- /* give a little time to let the thread wake up */
- msleep(100);
+ /* Wait for the task to wake up */
+ wait_for_completion(&isrt);
/* stop the tracing. */
tracing_stop();
diff --git a/kernel/trace/trace_stack.c b/kernel/trace/trace_stack.c
index d4545f49242e..0c1b165778e5 100644
--- a/kernel/trace/trace_stack.c
+++ b/kernel/trace/trace_stack.c
@@ -111,7 +111,8 @@ static inline void check_stack(void)
}
static void
-stack_trace_call(unsigned long ip, unsigned long parent_ip)
+stack_trace_call(unsigned long ip, unsigned long parent_ip,
+ struct ftrace_ops *op, struct pt_regs *pt_regs)
{
int cpu;
@@ -136,6 +137,7 @@ stack_trace_call(unsigned long ip, unsigned long parent_ip)
static struct ftrace_ops trace_ops __read_mostly =
{
.func = stack_trace_call,
+ .flags = FTRACE_OPS_FL_RECURSION_SAFE,
};
static ssize_t
diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c
index 6b245f64c8dd..2485a7d09b11 100644
--- a/kernel/trace/trace_syscalls.c
+++ b/kernel/trace/trace_syscalls.c
@@ -487,7 +487,7 @@ int __init init_ftrace_syscalls(void)
return 0;
}
-core_initcall(init_ftrace_syscalls);
+early_initcall(init_ftrace_syscalls);
#ifdef CONFIG_PERF_EVENTS
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-11 22:56:50 +0000