Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-tracegrafted

Pull tracing fixes from Steven Rostedt:

 - Fix error output of boot instance creation failure

   Currently if a boot instance creation fails, instead of printing out
   the name of the instance that failed, it prints "(null)". That is
   because it prints "cur_str" that had already been processed by
   strsep(). Print the saved name instead.

   While at it, print the error code of the failure.

 - Fix use-after-free for same named historgrams

   Histograms can be named so that they can be used in multiple events.
   But if the named histogram has a variable attached, the second event
   that uses the named histogram which duplicates it and needs to free
   the original after duplication leaves the old variable in place and
   still visible. If another histogram uses than variable, it will use
   the stale one which will try to reference the freed duplicate
   histogram and crash the kernel.

   Free the duplicate variables along with the duplicated histogram
   data.

 - Check return value of kthread_run() in event self test

   The events self tests uses a kthread for testing but does not check
   if it succeeded in creating a kthread. If the kthread creation were
   to fail, the code will still try to call kthread_stop() on the error
   returned.

 - Fix race between reading trace_pipe and updating subbuffer size

   If a user is reading the trace_pipe file at the same time they update
   the ring buffer sub-buffer size, can cause the trace_pipe read to
   read stale data. Add trace_access_lock() around updating the ring
   buffer sub-buffer size.

 - Fix eventfs_inode on failure path in creation of the events directory

   In the creation of the "events" directory, if after allocating the
   eventfs_inode a failure is detected, it calls cleanup_ei() which
   calls free_ei(). The free_ei() will test if eventfs_inode being freed
   has no children. It is a bug if it does. But on the failure case of
   the creation of the "events" directory, the children lists have not
   yet been initialized and the free will trigger a warning because
   list_empty() on an uninitialized list returns false.

   Move the initialization into init_ei() where it makes more sense and
   makes sure that a created eventfs_inode has its lists initialized
   upon creation.

 - Check return value of kthread_run() in ftrace direct sample code

   The sample code that shows how to use the ftrace direct calls does
   not test the return of kthread_run() to see if it succeeds. Return a
   failure if the kthread_run() doesn't succeed.

 - Clear user events state on fork in case of alloc failure

   On fork, the child gets a pointer to the parent's user events state.
   It makes a copy of it then updates the child's pointer to it. But if
   the allocation fails, the duplication function leaves the child with
   a pointer to its parent's descriptor. When the child cleans up its
   data, it will free the parent's descriptor while the parent is still
   using it.

   In the duplication function, set the child's user_event_mm to NULL
   before testing if the allocation succeeded, and when it exits it will
   not free the parent's descriptor.

 - Fix retry exhaustion in simple ring buffer reader swap

   simple_ring_buffer_swap_reader_page() starts with retry set to 8 and
   post-decrements it only after a failed link replacement. On the final
   attempt, a successful replacement leaves retry at zero, while a
   failed replacement leaves it at -1.

   But the check for success expects the retry value to be non-zero and
   exits with an error on zero. This is the opposite result. Fix it.

 - Fail nicely when the remote swap_reader_page() returns an error

   Currently, if the swap_reader_page() of a remote buffer fails, it
   triggers a WARN_ON_ONCE() and continues normally. Instead, have it
   exit with an error and a pr_warn() print instead of a full WARNING.

* tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace:
  ring-buffer: Stop remote reader update when page swap fails
  tracing: Fix retry exhaustion in simple ring buffer reader swap
  tracing/user_events: Clear copied tracing state before fork duplication
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify
  samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify
  eventfs: Initialize ei->children and ei->list in init_ei()
  tracing: Fix use-after-free in trace_pipe read on sub-buffer order change
  tracing: Fix crash passing ERR_PTR to kthread_stop()
  tracing: Fix use-after-free with same-name named triggers
  tracing: Fix logged instance name on creation failure

1 files changed, 322 insertions, 0 deletions

diff --git a/tools/perf/util/annotate-data.h b/tools/perf/util/annotate-data.h
new file mode 100644
index 000000000..c26130744
--- /dev/null
+++ b/tools/perf/util/annotate-data.h
@@ -0,0 +1,322 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _PERF_ANNOTATE_DATA_H
+#define _PERF_ANNOTATE_DATA_H
+
+#include <errno.h>
+#include <linux/compiler.h>
+#include <linux/rbtree.h>
+#include <linux/types.h>
+#include "dwarf-regs.h"
+#include "annotate.h"
+
+#ifdef HAVE_LIBDW_SUPPORT
+#include "debuginfo.h"
+#endif
+
+struct annotated_op_loc;
+struct debuginfo;
+struct evsel;
+struct hist_browser_timer;
+struct hist_entry;
+struct map_symbol;
+struct thread;
+
+#define pr_debug_dtp(fmt, ...)					\
+do {								\
+	if (debug_type_profile)					\
+		pr_info(fmt, ##__VA_ARGS__);			\
+	else							\
+		pr_debug3(fmt, ##__VA_ARGS__);			\
+} while (0)
+
+enum type_state_kind {
+	TSR_KIND_INVALID = 0,
+	TSR_KIND_TYPE,
+	TSR_KIND_PERCPU_BASE,
+	TSR_KIND_CONST,
+	TSR_KIND_PERCPU_POINTER,
+	TSR_KIND_POINTER,
+	TSR_KIND_CANARY,
+};
+
+/**
+ * struct annotated_member - Type of member field
+ * @node: List entry in the parent list
+ * @children: List head for child nodes
+ * @type_name: Name of the member type
+ * @var_name: Name of the member variable
+ * @offset: Offset from the outer data type
+ * @size: Size of the member field
+ *
+ * This represents a member type in a data type.
+ */
+struct annotated_member {
+	struct list_head node;
+	struct list_head children;
+	char *type_name;
+	char *var_name;
+	int offset;
+	int size;
+};
+
+/**
+ * struct type_hist_entry - Histogram entry per offset
+ * @nr_samples: Number of samples
+ * @period: Count of event
+ */
+struct type_hist_entry {
+	int nr_samples;
+	u64 period;
+};
+
+/**
+ * struct type_hist - Type histogram for each event
+ * @nr_samples: Total number of samples in this data type
+ * @period: Total count of the event in this data type
+ * @offset: Array of histogram entry
+ */
+struct type_hist {
+	u64			nr_samples;
+	u64			period;
+	struct type_hist_entry	addr[];
+};
+
+/**
+ * struct annotated_data_type - Data type to profile
+ * @node: RB-tree node for dso->type_tree
+ * @self: Actual type information
+ * @nr_histogram: Number of histogram entries
+ * @histograms: An array of pointers to histograms
+ *
+ * This represents a data type accessed by samples in the profile data.
+ */
+struct annotated_data_type {
+	struct rb_node node;
+	struct annotated_member self;
+	int nr_histograms;
+	struct type_hist **histograms;
+};
+
+extern struct annotated_data_type unknown_type;
+extern struct annotated_data_type stackop_type;
+extern struct annotated_data_type canary_type;
+
+/**
+ * struct data_loc_info - Data location information
+ * @arch: CPU architecture info
+ * @thread: Thread info
+ * @ms: Map and Symbol info
+ * @ip: Instruction address
+ * @var_addr: Data address (for global variables)
+ * @cpumode: CPU execution mode
+ * @op: Instruction operand location (regs and offset)
+ * @di: Debug info
+ * @fbreg: Frame base register
+ * @fb_cfa: Whether the frame needs to check CFA
+ * @type_offset: Final offset in the type
+ */
+struct data_loc_info {
+	/* These are input field, should be filled by caller */
+	const struct arch *arch;
+	struct thread *thread;
+	struct map_symbol *ms;
+	u64 ip;
+	u64 var_addr;
+	u8 cpumode;
+	struct annotated_op_loc *op;
+	struct debuginfo *di;
+
+	/* These are used internally */
+	int fbreg;
+	bool fb_cfa;
+
+	/* This is for the result */
+	int type_offset;
+};
+
+/**
+ * struct annotated_data_stat - Debug statistics
+ * @total: Total number of entry
+ * @no_sym: No symbol or map found
+ * @no_insn: Failed to get disasm line
+ * @no_insn_ops: The instruction has no operands
+ * @no_mem_ops: The instruction has no memory operands
+ * @no_reg: Failed to extract a register from the operand
+ * @no_dbginfo: The binary has no debug information
+ * @no_cuinfo: Failed to find a compile_unit
+ * @no_var: Failed to find a matching variable
+ * @no_typeinfo: Failed to get a type info for the variable
+ * @invalid_size: Failed to get a size info of the type
+ * @bad_offset: The access offset is out of the type
+ */
+struct annotated_data_stat {
+	int total;
+	int no_sym;
+	int no_insn;
+	int no_insn_ops;
+	int no_mem_ops;
+	int no_reg;
+	int no_dbginfo;
+	int no_cuinfo;
+	int no_var;
+	int no_typeinfo;
+	int invalid_size;
+	int bad_offset;
+	int insn_track;
+};
+extern struct annotated_data_stat ann_data_stat;
+
+#ifdef HAVE_LIBDW_SUPPORT
+/*
+ * Type information in a register, valid when @ok is true.
+ * The @caller_saved registers are invalidated after a function call.
+ */
+struct type_state_reg {
+	Dwarf_Die type;
+	u32 imm_value;
+	/*
+	 * The offset within the struct that the register points to.
+	 * A value of 0 means the register points to the beginning.
+	 * type_offset = op->offset + reg->offset
+	 */
+	s32 offset;
+	bool ok;
+	bool caller_saved;
+	/* DWARF location range tracking for register lifetime */
+	bool lifetime_active;
+	u64 lifetime_end;
+	u8 kind;
+	u8 copied_from;
+};
+
+/* Type information in a stack location, dynamically allocated */
+struct type_state_stack {
+	struct list_head list;
+	Dwarf_Die type;
+	int offset;
+	/* pointer offset, saves tsr->offset on the stack state */
+	int ptr_offset;
+	int size;
+	bool compound;
+	u8 kind;
+};
+
+/*
+ * Maximum number of registers tracked in type_state.
+ *
+ * This limit must cover all supported architectures, since perf
+ * may analyze perf.data files generated on systems with a different
+ * register set. Use 32 as a safe upper bound instead of relying on
+ * build-arch specific values.
+ */
+#define TYPE_STATE_MAX_REGS  32
+
+/*
+ * State table to maintain type info in each register and stack location.
+ * It'll be updated when new variable is allocated or type info is moved
+ * to a new location (register or stack).  As it'd be used with the
+ * shortest path of basic blocks, it only maintains a single table.
+ */
+struct type_state {
+	/* state of general purpose registers */
+	struct type_state_reg regs[TYPE_STATE_MAX_REGS];
+	/* state of stack location */
+	struct list_head stack_vars;
+	/* return value register */
+	int ret_reg;
+	/* stack pointer register */
+	int stack_reg;
+};
+
+/* Returns data type at the location (ip, reg, offset) */
+struct annotated_data_type *find_data_type(struct data_loc_info *dloc);
+
+/* Update type access histogram at the given offset */
+int annotated_data_type__update_samples(struct annotated_data_type *adt,
+					struct evsel *evsel, int offset,
+					int nr_samples, u64 period);
+
+/* Release all data type information in the tree */
+void annotated_data_type__tree_delete(struct rb_root *root);
+
+/* Release all global variable information in the tree */
+void global_var_type__tree_delete(struct rb_root *root);
+
+/* Print data type annotation (including members) on stdout */
+int hist_entry__annotate_data_tty(struct hist_entry *he, struct evsel *evsel);
+
+/* Get name of member field at the given offset in the data type */
+int annotated_data_type__get_member_name(struct annotated_data_type *adt,
+					 char *buf, size_t sz, int member_offset);
+
+bool has_reg_type(struct type_state *state, int reg);
+struct type_state_stack *findnew_stack_state(struct type_state *state,
+						int offset, u8 kind,
+						Dwarf_Die *type_die,
+						int ptr_offset);
+void set_stack_state(struct type_state_stack *stack, int offset, u8 kind,
+				Dwarf_Die *type_die, int ptr_offset);
+struct type_state_stack *find_stack_state(struct type_state *state,
+						int offset);
+bool get_global_var_type(Dwarf_Die *cu_die, struct data_loc_info *dloc,
+				u64 ip, u64 var_addr, int *var_offset,
+				Dwarf_Die *type_die);
+bool get_global_var_info(struct data_loc_info *dloc, u64 addr,
+				const char **var_name, int *var_offset);
+void pr_debug_type_name(Dwarf_Die *die, enum type_state_kind kind);
+
+#else /* HAVE_LIBDW_SUPPORT */
+
+static inline struct annotated_data_type *
+find_data_type(struct data_loc_info *dloc __maybe_unused)
+{
+	return NULL;
+}
+
+static inline int
+annotated_data_type__update_samples(struct annotated_data_type *adt __maybe_unused,
+				    struct evsel *evsel __maybe_unused,
+				    int offset __maybe_unused,
+				    int nr_samples __maybe_unused,
+				    u64 period __maybe_unused)
+{
+	return -1;
+}
+
+static inline void annotated_data_type__tree_delete(struct rb_root *root __maybe_unused)
+{
+}
+
+static inline void global_var_type__tree_delete(struct rb_root *root __maybe_unused)
+{
+}
+
+static inline int hist_entry__annotate_data_tty(struct hist_entry *he __maybe_unused,
+						struct evsel *evsel __maybe_unused)
+{
+	return -1;
+}
+
+static inline int annotated_data_type__get_member_name(struct annotated_data_type *adt __maybe_unused,
+						       char *buf __maybe_unused,
+						       size_t sz __maybe_unused,
+						       int member_offset __maybe_unused)
+{
+	return -1;
+}
+
+#endif /* HAVE_LIBDW_SUPPORT */
+
+#ifdef HAVE_SLANG_SUPPORT
+int hist_entry__annotate_data_tui(struct hist_entry *he, struct evsel *evsel,
+				  struct hist_browser_timer *hbt);
+#else
+static inline int hist_entry__annotate_data_tui(struct hist_entry *he __maybe_unused,
+						struct evsel *evsel __maybe_unused,
+						struct hist_browser_timer *hbt __maybe_unused)
+{
+	return -1;
+}
+#endif /* HAVE_SLANG_SUPPORT */
+
+#endif /* _PERF_ANNOTATE_DATA_H */