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, 331 insertions, 0 deletions

diff --git a/tools/perf/util/machine.h b/tools/perf/util/machine.h
new file mode 100644
index 000000000..26f982706
--- /dev/null
+++ b/tools/perf/util/machine.h
@@ -0,0 +1,331 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __PERF_MACHINE_H
+#define __PERF_MACHINE_H
+
+#include <sys/types.h>
+#include <linux/rbtree.h>
+#include "maps.h"
+#include "dsos.h"
+#include "rwsem.h"
+#include "threads.h"
+
+struct addr_location;
+struct branch_stack;
+struct dso;
+struct dso_id;
+struct evsel;
+struct perf_sample;
+struct symbol;
+struct target;
+struct thread;
+union perf_event;
+struct machines;
+
+/* Native host kernel uses -1 as pid index in machine */
+#define	HOST_KERNEL_ID			(-1)
+#define	DEFAULT_GUEST_KERNEL_ID		(0)
+
+extern const char *ref_reloc_sym_names[];
+
+struct vdso_info;
+
+struct machine {
+	struct rb_node	  rb_node;
+	pid_t		  pid;
+	u16		  id_hdr_size;
+	bool		  comm_exec;
+	bool		  kptr_restrict_warned;
+	bool		  single_address_space;
+	char		  *root_dir;
+	char		  *mmap_name;
+	char		  *kallsyms_filename;
+	struct threads    threads;
+	struct vdso_info  *vdso_info;
+	struct perf_env   *env;
+	struct dsos	  dsos;
+	struct maps	  *kmaps;
+	struct map	  *vmlinux_map;
+	u64		  kernel_start;
+	struct {
+		u64	  text_start;
+		u64	  text_end;
+	} sched, lock, traceiter, trace;
+	/*
+	 * The current parallelism level (number of threads that run on CPUs).
+	 * This value can be less than 1, or larger than the total number
+	 * of CPUs, if events are poorly ordered.
+	 */
+	int		  parallelism;
+	pid_t		  *current_tid;
+	size_t		  current_tid_sz;
+	union { /* Tool specific area */
+		void	  *priv;
+		u64	  db_id;
+	};
+	struct machines   *machines;
+	bool		  trampolines_mapped;
+};
+
+/*
+ * The main kernel (vmlinux) map
+ */
+static inline
+struct map *machine__kernel_map(struct machine *machine)
+{
+	return machine->vmlinux_map;
+}
+
+/*
+ * kernel (the one returned by machine__kernel_map()) plus kernel modules maps
+ */
+static inline
+struct maps *machine__kernel_maps(struct machine *machine)
+{
+	return machine->kmaps;
+}
+
+int machine__get_kernel_start(struct machine *machine);
+
+static inline u64 machine__kernel_start(struct machine *machine)
+{
+	if (!machine->kernel_start)
+		machine__get_kernel_start(machine);
+	return machine->kernel_start;
+}
+
+static inline bool machine__kernel_ip(struct machine *machine, u64 ip)
+{
+	u64 kernel_start = machine__kernel_start(machine);
+
+	return ip >= kernel_start;
+}
+
+u8 machine__addr_cpumode(struct machine *machine, u8 cpumode, u64 addr);
+
+struct thread *machine__find_thread(struct machine *machine, pid_t pid,
+				    pid_t tid);
+struct thread *machine__idle_thread(struct machine *machine);
+struct comm *machine__thread_exec_comm(struct machine *machine,
+				       struct thread *thread);
+
+int machine__process_comm_event(struct machine *machine, union perf_event *event,
+				struct perf_sample *sample);
+int machine__process_exit_event(struct machine *machine, union perf_event *event,
+				struct perf_sample *sample);
+int machine__process_fork_event(struct machine *machine, union perf_event *event,
+				struct perf_sample *sample);
+int machine__process_lost_event(struct machine *machine, union perf_event *event,
+				struct perf_sample *sample);
+int machine__process_lost_samples_event(struct machine *machine, union perf_event *event,
+					struct perf_sample *sample);
+int machine__process_aux_event(struct machine *machine,
+			       union perf_event *event);
+int machine__process_itrace_start_event(struct machine *machine,
+					union perf_event *event);
+int machine__process_aux_output_hw_id_event(struct machine *machine,
+					    union perf_event *event);
+int machine__process_switch_event(struct machine *machine,
+				  union perf_event *event);
+int machine__process_namespaces_event(struct machine *machine,
+				      union perf_event *event,
+				      struct perf_sample *sample);
+int machine__process_cgroup_event(struct machine *machine,
+				  union perf_event *event,
+				  struct perf_sample *sample);
+int machine__process_mmap_event(struct machine *machine, union perf_event *event,
+				struct perf_sample *sample);
+int machine__process_mmap2_event(struct machine *machine, union perf_event *event,
+				 struct perf_sample *sample);
+int machine__process_ksymbol(struct machine *machine,
+			     union perf_event *event,
+			     struct perf_sample *sample);
+int machine__process_text_poke(struct machine *machine,
+			       union perf_event *event,
+			       struct perf_sample *sample);
+int machine__process_event(struct machine *machine, union perf_event *event,
+				struct perf_sample *sample);
+
+typedef void (*machine__process_t)(struct machine *machine, void *data);
+
+struct machines {
+	struct machine host;
+	struct rb_root_cached guests;
+};
+
+int machines__init(struct machines *machines);
+void machines__exit(struct machines *machines);
+
+void machines__process_guests(struct machines *machines,
+			      machine__process_t process, void *data);
+
+struct machine *machines__add(struct machines *machines, pid_t pid,
+			      const char *root_dir);
+struct machine *machines__find(struct machines *machines, pid_t pid);
+struct machine *machines__findnew(struct machines *machines, pid_t pid);
+struct machine *machines__find_guest(struct machines *machines, pid_t pid);
+struct thread *machines__findnew_guest_code(struct machines *machines, pid_t pid);
+struct thread *machine__findnew_guest_code(struct machine *machine, pid_t pid);
+
+void machines__set_id_hdr_size(struct machines *machines, u16 id_hdr_size);
+void machines__set_comm_exec(struct machines *machines, bool comm_exec);
+
+struct machine *machine__new_host(struct perf_env *host_env);
+struct machine *machine__new_kallsyms(struct perf_env *host_env);
+struct machine *machine__new_live(struct perf_env *host_env, bool kernel_maps, pid_t pid);
+int machine__init(struct machine *machine, const char *root_dir, pid_t pid);
+void machine__exit(struct machine *machine);
+void machine__delete_threads(struct machine *machine);
+void machine__delete(struct machine *machine);
+void machine__remove_thread(struct machine *machine, struct thread *th);
+
+struct branch_info *sample__resolve_bstack(struct perf_sample *sample,
+					   struct addr_location *al);
+struct mem_info *sample__resolve_mem(struct perf_sample *sample,
+				     struct addr_location *al);
+
+struct callchain_cursor;
+
+int __thread__resolve_callchain(struct thread *thread,
+				struct callchain_cursor *cursor,
+				struct perf_sample *sample,
+				struct symbol **parent,
+				struct addr_location *root_al,
+				int max_stack,
+				bool symbols);
+
+static inline int thread__resolve_callchain(struct thread *thread,
+					    struct callchain_cursor *cursor,
+					    struct perf_sample *sample,
+					    struct symbol **parent,
+					    struct addr_location *root_al,
+					    int max_stack)
+{
+	return __thread__resolve_callchain(thread,
+					   cursor,
+					   sample,
+					   parent,
+					   root_al,
+					   max_stack,
+					   /*symbols=*/true);
+}
+
+/*
+ * Default guest kernel is defined by parameter --guestkallsyms
+ * and --guestmodules
+ */
+static inline bool machine__is_default_guest(struct machine *machine)
+{
+	return machine ? machine->pid == DEFAULT_GUEST_KERNEL_ID : false;
+}
+
+static inline bool machine__is_host(struct machine *machine)
+{
+	return machine ? machine->pid == HOST_KERNEL_ID : false;
+}
+
+bool machine__is_lock_function(struct machine *machine, u64 addr);
+int machine__nr_cpus_avail(struct machine *machine);
+
+struct thread *machine__findnew_thread(struct machine *machine, pid_t pid, pid_t tid);
+
+struct dso *machine__findnew_dso_id(struct machine *machine, const char *filename,
+				    const struct dso_id *id);
+struct dso *machine__findnew_dso(struct machine *machine, const char *filename);
+
+size_t machine__fprintf(struct machine *machine, FILE *fp);
+
+static inline
+struct symbol *machine__find_kernel_symbol(struct machine *machine, u64 addr,
+					   struct map **mapp)
+{
+	return maps__find_symbol(machine->kmaps, addr, mapp);
+}
+
+static inline
+struct symbol *machine__find_kernel_symbol_by_name(struct machine *machine,
+						   const char *name,
+						   struct map **mapp)
+{
+	return maps__find_symbol_by_name(machine->kmaps, name, mapp);
+}
+
+int arch__fix_module_text_start(u64 *start, u64 *size, const char *name);
+
+int machine__load_kallsyms(struct machine *machine, const char *filename);
+
+int machine__load_vmlinux_path(struct machine *machine);
+
+size_t machine__fprintf_dsos_buildid(struct machine *machine, FILE *fp,
+				     bool (skip)(struct dso *dso, int parm), int parm);
+size_t machines__fprintf_dsos(struct machines *machines, FILE *fp);
+size_t machines__fprintf_dsos_buildid(struct machines *machines, FILE *fp,
+				     bool (skip)(struct dso *dso, int parm), int parm);
+
+void machine__destroy_kernel_maps(struct machine *machine);
+int machine__create_kernel_maps(struct machine *machine);
+
+int machines__create_kernel_maps(struct machines *machines, pid_t pid);
+int machines__create_guest_kernel_maps(struct machines *machines);
+void machines__destroy_kernel_maps(struct machines *machines);
+
+typedef int (*machine__dso_t)(struct dso *dso, struct machine *machine, void *priv);
+
+int machine__for_each_dso(struct machine *machine, machine__dso_t fn,
+			  void *priv);
+
+typedef int (*machine__map_t)(struct map *map, void *priv);
+int machine__for_each_kernel_map(struct machine *machine, machine__map_t fn,
+				 void *priv);
+
+int machine__for_each_thread(struct machine *machine,
+			     int (*fn)(struct thread *thread, void *p),
+			     void *priv);
+int machines__for_each_thread(struct machines *machines,
+			      int (*fn)(struct thread *thread, void *p),
+			      void *priv);
+
+struct thread_list {
+	struct list_head	 list;
+	struct thread		*thread;
+};
+
+/* Make a list of struct thread_list based on threads in the machine. */
+int machine__thread_list(struct machine *machine, struct list_head *list);
+/* Free up the nodes within the thread_list list. */
+void thread_list__delete(struct list_head *list);
+
+pid_t machine__get_current_tid(struct machine *machine, int cpu);
+int machine__set_current_tid(struct machine *machine, int cpu, pid_t pid,
+			     pid_t tid);
+/*
+ * For use with libtraceevent's tep_set_function_resolver()
+ */
+char *machine__resolve_kernel_addr(void *vmachine, unsigned long long *addrp, char **modp);
+
+void machine__get_kallsyms_filename(struct machine *machine, char *buf,
+				    size_t bufsz);
+
+int machine__create_extra_kernel_maps(struct machine *machine,
+				      struct dso *kernel);
+
+/* Kernel-space maps for symbols that are outside the main kernel map and module maps */
+struct extra_kernel_map {
+	u64 start;
+	u64 end;
+	u64 pgoff;
+	char name[KMAP_NAME_LEN];
+};
+
+int machine__create_extra_kernel_map(struct machine *machine,
+				     struct dso *kernel,
+				     struct extra_kernel_map *xm);
+
+int machine__map_x86_64_entry_trampolines(struct machine *machine,
+					  struct dso *kernel);
+
+int machine__resolve(struct machine *machine, struct addr_location *al,
+		     struct perf_sample *sample);
+
+int machine__hit_all_dsos(struct machine *machine);
+
+#endif /* __PERF_MACHINE_H */