Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull perf fixes from Ingo Molnar:
 "Various fixlets:

  On the kernel side:

   - fix a race
   - fix a bug in the handling of the perf ring-buffer data page

  On the tooling side:

   - fix the handling of certain corrupted perf.data files
   - fix a bug in 'perf probe'
   - fix a bug in 'perf record + perf sched'
   - fix a bug in 'make install'
   - fix a bug in libaudit feature-detection on certain distros"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf session: Fix infinite loop on invalid perf.data file
  perf tools: Fix installation of libexec components
  perf probe: Fix to find line information for probe list
  perf tools: Fix libaudit test
  perf stat: Set child_pid after perf_evlist__prepare_workload()
  perf tools: Add default handler for mmap2 events
  perf/x86: Clean up cap_user_time* setting
  perf: Fix perf_pmu_migrate_context

arch/x86/kernel/cpu/perf_event.c

@@ -1888,10 +1888,7 @@ void arch_perf_update_userpage(struct perf_event_mmap_page *userpg, u64 now)
 	userpg->cap_user_rdpmc = x86_pmu.attr_rdpmc;
 	userpg->pmc_width = x86_pmu.cntval_bits;
 
-	if (!boot_cpu_has(X86_FEATURE_CONSTANT_TSC))
-		return;
-
-	if (!boot_cpu_has(X86_FEATURE_NONSTOP_TSC))
+	if (!sched_clock_stable)
 		return;
 
 	userpg->cap_user_time = 1;
@@ -1899,10 +1896,8 @@ void arch_perf_update_userpage(struct perf_event_mmap_page *userpg, u64 now)
 	userpg->time_shift = CYC2NS_SCALE_FACTOR;
 	userpg->time_offset = this_cpu_read(cyc2ns_offset) - now;
 
-	if (sched_clock_stable && !check_tsc_disabled()) {
 	userpg->cap_user_time_zero = 1;
 	userpg->time_zero = this_cpu_read(cyc2ns_offset);
-	}
 }
 
 /*

include/linux/perf_event.h

@@ -294,9 +294,31 @@ struct ring_buffer;
  */
 struct perf_event {
 #ifdef CONFIG_PERF_EVENTS
-	struct list_head		group_entry;
+	/*
+	 * entry onto perf_event_context::event_list;
+	 *   modifications require ctx->lock
+	 *   RCU safe iterations.
+	 */
 	struct list_head		event_entry;
+
+	/*
+	 * XXX: group_entry and sibling_list should be mutually exclusive;
+	 * either you're a sibling on a group, or you're the group leader.
+	 * Rework the code to always use the same list element.
+	 *
+	 * Locked for modification by both ctx->mutex and ctx->lock; holding
+	 * either sufficies for read.
+	 */
+	struct list_head		group_entry;
 	struct list_head		sibling_list;
+
+	/*
+	 * We need storage to track the entries in perf_pmu_migrate_context; we
+	 * cannot use the event_entry because of RCU and we want to keep the
+	 * group in tact which avoids us using the other two entries.
+	 */
+	struct list_head		migrate_entry;
+
 	struct hlist_node		hlist_entry;
 	int				nr_siblings;
 	int				group_flags;

kernel/events/core.c

@@ -7234,15 +7234,15 @@ void perf_pmu_migrate_context(struct pmu *pmu, int src_cpu, int dst_cpu)
 		perf_remove_from_context(event);
 		unaccount_event_cpu(event, src_cpu);
 		put_ctx(src_ctx);
-		list_add(&event->event_entry, &events);
+		list_add(&event->migrate_entry, &events);
 	}
 	mutex_unlock(&src_ctx->mutex);
 
 	synchronize_rcu();
 
 	mutex_lock(&dst_ctx->mutex);
-	list_for_each_entry_safe(event, tmp, &events, event_entry) {
-		list_del(&event->event_entry);
+	list_for_each_entry_safe(event, tmp, &events, migrate_entry) {
+		list_del(&event->migrate_entry);
 		if (event->state >= PERF_EVENT_STATE_OFF)
 			event->state = PERF_EVENT_STATE_INACTIVE;
 		account_event_cpu(event, dst_cpu);

tools/perf/Makefile

@@ -770,6 +770,7 @@ check: $(OUTPUT)common-cmds.h
 install-bin: all
 	$(INSTALL) -d -m 755 '$(DESTDIR_SQ)$(bindir_SQ)'
 	$(INSTALL) $(OUTPUT)perf '$(DESTDIR_SQ)$(bindir_SQ)'
+	$(INSTALL) -d -m 755 '$(DESTDIR_SQ)$(perfexec_instdir_SQ)'
 	$(INSTALL) $(OUTPUT)perf-archive -t '$(DESTDIR_SQ)$(perfexec_instdir_SQ)'
 ifndef NO_LIBPERL
 	$(INSTALL) -d -m 755 '$(DESTDIR_SQ)$(perfexec_instdir_SQ)/scripts/perl/Perf-Trace-Util/lib/Perf/Trace'

tools/perf/builtin-stat.c

@@ -457,6 +457,7 @@ static int __run_perf_stat(int argc, const char **argv)
 			perror("failed to prepare workload");
 			return -1;
 		}
+		child_pid = evsel_list->workload.pid;
 	}
 
 	if (group)

tools/perf/config/feature-tests.mak

@@ -219,7 +219,7 @@ define SOURCE_LIBAUDIT
 
 int main(void)
 {
-	printf(\"error message: %s\n\", audit_errno_to_name(0));
+	printf(\"error message: %s\", audit_errno_to_name(0));
 	return audit_open();
 }
 endef

tools/perf/util/dwarf-aux.c

@@ -426,7 +426,7 @@ static int __die_search_func_cb(Dwarf_Die *fn_die, void *data)
  * @die_mem: a buffer for result DIE
  *
  * Search a non-inlined function DIE which includes @addr. Stores the
- * DIE to @die_mem and returns it if found. Returns NULl if failed.
+ * DIE to @die_mem and returns it if found. Returns NULL if failed.
  */
 Dwarf_Die *die_find_realfunc(Dwarf_Die *cu_die, Dwarf_Addr addr,
 				    Dwarf_Die *die_mem)
@@ -453,16 +453,33 @@ static int __die_find_inline_cb(Dwarf_Die *die_mem, void *data)
 	return DIE_FIND_CB_CONTINUE;
 }
 
+/**
+ * die_find_top_inlinefunc - Search the top inlined function at given address
+ * @sp_die: a subprogram DIE which including @addr
+ * @addr: target address
+ * @die_mem: a buffer for result DIE
+ *
+ * Search an inlined function DIE which includes @addr. Stores the
+ * DIE to @die_mem and returns it if found. Returns NULL if failed.
+ * Even if several inlined functions are expanded recursively, this
+ * doesn't trace it down, and returns the topmost one.
+ */
+Dwarf_Die *die_find_top_inlinefunc(Dwarf_Die *sp_die, Dwarf_Addr addr,
+				   Dwarf_Die *die_mem)
+{
+	return die_find_child(sp_die, __die_find_inline_cb, &addr, die_mem);
+}
+
 /**
  * die_find_inlinefunc - Search an inlined function at given address
- * @cu_die: a CU DIE which including @addr
+ * @sp_die: a subprogram DIE which including @addr
  * @addr: target address
  * @die_mem: a buffer for result DIE
  *
  * Search an inlined function DIE which includes @addr. Stores the
- * DIE to @die_mem and returns it if found. Returns NULl if failed.
+ * DIE to @die_mem and returns it if found. Returns NULL if failed.
  * If several inlined functions are expanded recursively, this trace
- * it and returns deepest one.
+ * it down and returns deepest one.
  */
 Dwarf_Die *die_find_inlinefunc(Dwarf_Die *sp_die, Dwarf_Addr addr,
 			       Dwarf_Die *die_mem)

tools/perf/util/dwarf-aux.h

@@ -79,7 +79,11 @@ extern Dwarf_Die *die_find_child(Dwarf_Die *rt_die,
 extern Dwarf_Die *die_find_realfunc(Dwarf_Die *cu_die, Dwarf_Addr addr,
 				    Dwarf_Die *die_mem);
 
-/* Search an inlined function including given address */
+/* Search the top inlined function including given address */
+extern Dwarf_Die *die_find_top_inlinefunc(Dwarf_Die *sp_die, Dwarf_Addr addr,
+					  Dwarf_Die *die_mem);
+
+/* Search the deepest inlined function including given address */
 extern Dwarf_Die *die_find_inlinefunc(Dwarf_Die *sp_die, Dwarf_Addr addr,
 				      Dwarf_Die *die_mem);
 

tools/perf/util/header.c

@@ -2768,6 +2768,18 @@ int perf_session__read_header(struct perf_session *session)
 	if (perf_file_header__read(&f_header, header, fd) < 0)
 		return -EINVAL;
 
+	/*
+	 * Sanity check that perf.data was written cleanly; data size is
+	 * initialized to 0 and updated only if the on_exit function is run.
+	 * If data size is still 0 then the file contains only partial
+	 * information.  Just warn user and process it as much as it can.
+	 */
+	if (f_header.data.size == 0) {
+		pr_warning("WARNING: The %s file's data size field is 0 which is unexpected.\n"
+			   "Was the 'perf record' command properly terminated?\n",
+			   session->filename);
+	}
+
 	nr_attrs = f_header.attrs.size / f_header.attr_size;
 	lseek(fd, f_header.attrs.offset, SEEK_SET);
 

tools/perf/util/probe-finder.c

@@ -1327,8 +1327,8 @@ int debuginfo__find_probe_point(struct debuginfo *self, unsigned long addr,
 				struct perf_probe_point *ppt)
 {
 	Dwarf_Die cudie, spdie, indie;
-	Dwarf_Addr _addr, baseaddr;
-	const char *fname = NULL, *func = NULL, *tmp;
+	Dwarf_Addr _addr = 0, baseaddr = 0;
+	const char *fname = NULL, *func = NULL, *basefunc = NULL, *tmp;
 	int baseline = 0, lineno = 0, ret = 0;
 
 	/* Adjust address with bias */
@@ -1349,27 +1349,36 @@ int debuginfo__find_probe_point(struct debuginfo *self, unsigned long addr,
 	/* Find a corresponding function (name, baseline and baseaddr) */
 	if (die_find_realfunc(&cudie, (Dwarf_Addr)addr, &spdie)) {
 		/* Get function entry information */
-		tmp = dwarf_diename(&spdie);
-		if (!tmp ||
+		func = basefunc = dwarf_diename(&spdie);
+		if (!func ||
 		    dwarf_entrypc(&spdie, &baseaddr) != 0 ||
-		    dwarf_decl_line(&spdie, &baseline) != 0)
+		    dwarf_decl_line(&spdie, &baseline) != 0) {
+			lineno = 0;
 			goto post;
-		func = tmp;
+		}
 
-		if (addr == (unsigned long)baseaddr)
+		if (addr == (unsigned long)baseaddr) {
 			/* Function entry - Relative line number is 0 */
 			lineno = baseline;
-		else if (die_find_inlinefunc(&spdie, (Dwarf_Addr)addr,
+			fname = dwarf_decl_file(&spdie);
+			goto post;
+		}
+
+		/* Track down the inline functions step by step */
+		while (die_find_top_inlinefunc(&spdie, (Dwarf_Addr)addr,
 						&indie)) {
+			/* There is an inline function */
 			if (dwarf_entrypc(&indie, &_addr) == 0 &&
-			    _addr == addr)
+			    _addr == addr) {
 				/*
 				 * addr is at an inline function entry.
 				 * In this case, lineno should be the call-site
-				 * line number.
+				 * line number. (overwrite lineinfo)
 				 */
 				lineno = die_get_call_lineno(&indie);
-			else {
+				fname = die_get_call_file(&indie);
+				break;
+			} else {
 				/*
 				 * addr is in an inline function body.
 				 * Since lineno points one of the lines
@@ -1377,19 +1386,27 @@ int debuginfo__find_probe_point(struct debuginfo *self, unsigned long addr,
 				 * be the entry line of the inline function.
 				 */
 				tmp = dwarf_diename(&indie);
-				if (tmp &&
-				    dwarf_decl_line(&spdie, &baseline) == 0)
+				if (!tmp ||
+				    dwarf_decl_line(&indie, &baseline) != 0)
+					break;
 				func = tmp;
+				spdie = indie;
 			}
 		}
+		/* Verify the lineno and baseline are in a same file */
+		tmp = dwarf_decl_file(&spdie);
+		if (!tmp || strcmp(tmp, fname) != 0)
+			lineno = 0;
 	}
 
 post:
 	/* Make a relative line number or an offset */
 	if (lineno)
 		ppt->line = lineno - baseline;
-	else if (func)
+	else if (basefunc) {
 		ppt->offset = addr - (unsigned long)baseaddr;
+		func = basefunc;
+	}
 
 	/* Duplicate strings */
 	if (func) {

tools/perf/util/session.c

@@ -256,6 +256,8 @@ void perf_tool__fill_defaults(struct perf_tool *tool)
 		tool->sample = process_event_sample_stub;
 	if (tool->mmap == NULL)
 		tool->mmap = process_event_stub;
+	if (tool->mmap2 == NULL)
+		tool->mmap2 = process_event_stub;
 	if (tool->comm == NULL)
 		tool->comm = process_event_stub;
 	if (tool->fork == NULL)
@@ -1310,7 +1312,7 @@ int __perf_session__process_events(struct perf_session *session,
 	file_offset = page_offset;
 	head = data_offset - page_offset;
 
-	if (data_offset + data_size < file_size)
+	if (data_size && (data_offset + data_size < file_size))
 		file_size = data_offset + data_size;
 
 	progress_next = file_size / 16;