Merge tag 'perf-urgent-2020-04-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull more perf updates from Thomas Gleixner:
 "Perf updates all over the place:

  core:

   - Support for cgroup tracking in samples to allow cgroup based
     analysis

  tools:

   - Support for cgroup analysis

   - Commandline option and hotkey for perf top to change the sort order

   - A set of fixes all over the place

   - Various build system related improvements

   - Updates of the X86 pmu event JSON data

   - Documentation updates"

* tag 'perf-urgent-2020-04-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (55 commits)
  perf python: Fix clang detection to strip out options passed in $CC
  perf tools: Support Python 3.8+ in Makefile
  perf script: Fix invalid read of directory entry after closedir()
  perf script report: Fix SEGFAULT when using DWARF mode
  perf script: add -S/--symbols documentation
  perf pmu-events x86: Use CPU_CLK_UNHALTED.THREAD in Kernel_Utilization metric
  perf events parser: Add missing Intel CPU events to parser
  perf script: Allow --symbol to accept hexadecimal addresses
  perf report/top TUI: Fix title line formatting
  perf top: Support hotkey to change sort order
  perf top: Support --group-sort-idx to change the sort order
  perf symbols: Fix arm64 gap between kernel start and module end
  perf build-test: Honour JOBS to override detection of number of cores
  perf script: Add --show-cgroup-events option
  perf top: Add --all-cgroups option
  perf record: Add --all-cgroups option
  perf record: Support synthesizing cgroup events
  perf report: Add 'cgroup' sort key
  perf cgroup: Maintain cgroup hierarchy
  perf tools: Basic support for CGROUP event
  ...

1 files changed, 130 insertions, 0 deletions

diff --git a/tools/perf/util/synthetic-events.c b/tools/perf/util/synthetic-events.c
index 3f28af39f9c6..a661b122d9d8 100644
--- a/tools/perf/util/synthetic-events.c
+++ b/tools/perf/util/synthetic-events.c
@@ -16,6 +16,7 @@
 #include "util/synthetic-events.h"
 #include "util/target.h"
 #include "util/time-utils.h"
+#include "util/cgroup.h"
 #include <linux/bitops.h>
 #include <linux/kernel.h>
 #include <linux/string.h>
@@ -414,6 +415,127 @@ out:
 	return rc;
 }
 
+#ifdef HAVE_FILE_HANDLE
+static int perf_event__synthesize_cgroup(struct perf_tool *tool,
+					 union perf_event *event,
+					 char *path, size_t mount_len,
+					 perf_event__handler_t process,
+					 struct machine *machine)
+{
+	size_t event_size = sizeof(event->cgroup) - sizeof(event->cgroup.path);
+	size_t path_len = strlen(path) - mount_len + 1;
+	struct {
+		struct file_handle fh;
+		uint64_t cgroup_id;
+	} handle;
+	int mount_id;
+
+	while (path_len % sizeof(u64))
+		path[mount_len + path_len++] = '\0';
+
+	memset(&event->cgroup, 0, event_size);
+
+	event->cgroup.header.type = PERF_RECORD_CGROUP;
+	event->cgroup.header.size = event_size + path_len + machine->id_hdr_size;
+
+	handle.fh.handle_bytes = sizeof(handle.cgroup_id);
+	if (name_to_handle_at(AT_FDCWD, path, &handle.fh, &mount_id, 0) < 0) {
+		pr_debug("stat failed: %s\n", path);
+		return -1;
+	}
+
+	event->cgroup.id = handle.cgroup_id;
+	strncpy(event->cgroup.path, path + mount_len, path_len);
+	memset(event->cgroup.path + path_len, 0, machine->id_hdr_size);
+
+	if (perf_tool__process_synth_event(tool, event, machine, process) < 0) {
+		pr_debug("process synth event failed\n");
+		return -1;
+	}
+
+	return 0;
+}
+
+static int perf_event__walk_cgroup_tree(struct perf_tool *tool,
+					union perf_event *event,
+					char *path, size_t mount_len,
+					perf_event__handler_t process,
+					struct machine *machine)
+{
+	size_t pos = strlen(path);
+	DIR *d;
+	struct dirent *dent;
+	int ret = 0;
+
+	if (perf_event__synthesize_cgroup(tool, event, path, mount_len,
+					  process, machine) < 0)
+		return -1;
+
+	d = opendir(path);
+	if (d == NULL) {
+		pr_debug("failed to open directory: %s\n", path);
+		return -1;
+	}
+
+	while ((dent = readdir(d)) != NULL) {
+		if (dent->d_type != DT_DIR)
+			continue;
+		if (!strcmp(dent->d_name, ".") ||
+		    !strcmp(dent->d_name, ".."))
+			continue;
+
+		/* any sane path should be less than PATH_MAX */
+		if (strlen(path) + strlen(dent->d_name) + 1 >= PATH_MAX)
+			continue;
+
+		if (path[pos - 1] != '/')
+			strcat(path, "/");
+		strcat(path, dent->d_name);
+
+		ret = perf_event__walk_cgroup_tree(tool, event, path,
+						   mount_len, process, machine);
+		if (ret < 0)
+			break;
+
+		path[pos] = '\0';
+	}
+
+	closedir(d);
+	return ret;
+}
+
+int perf_event__synthesize_cgroups(struct perf_tool *tool,
+				   perf_event__handler_t process,
+				   struct machine *machine)
+{
+	union perf_event event;
+	char cgrp_root[PATH_MAX];
+	size_t mount_len;  /* length of mount point in the path */
+
+	if (cgroupfs_find_mountpoint(cgrp_root, PATH_MAX, "perf_event") < 0) {
+		pr_debug("cannot find cgroup mount point\n");
+		return -1;
+	}
+
+	mount_len = strlen(cgrp_root);
+	/* make sure the path starts with a slash (after mount point) */
+	strcat(cgrp_root, "/");
+
+	if (perf_event__walk_cgroup_tree(tool, &event, cgrp_root, mount_len,
+					 process, machine) < 0)
+		return -1;
+
+	return 0;
+}
+#else
+int perf_event__synthesize_cgroups(struct perf_tool *tool __maybe_unused,
+				   perf_event__handler_t process __maybe_unused,
+				   struct machine *machine __maybe_unused)
+{
+	return -1;
+}
+#endif
+
 int perf_event__synthesize_modules(struct perf_tool *tool, perf_event__handler_t process,
 				   struct machine *machine)
 {
@@ -1230,6 +1352,9 @@ size_t perf_event__sample_event_size(const struct perf_sample *sample, u64 type,
 	if (type & PERF_SAMPLE_PHYS_ADDR)
 		result += sizeof(u64);
 
+	if (type & PERF_SAMPLE_CGROUP)
+		result += sizeof(u64);
+
 	if (type & PERF_SAMPLE_AUX) {
 		result += sizeof(u64);
 		result += sample->aux_sample.size;
@@ -1404,6 +1529,11 @@ int perf_event__synthesize_sample(union perf_event *event, u64 type, u64 read_fo
 		array++;
 	}
 
+	if (type & PERF_SAMPLE_CGROUP) {
+		*array = sample->cgroup;
+		array++;
+	}
+
 	if (type & PERF_SAMPLE_AUX) {
 		sz = sample->aux_sample.size;
 		*array++ = sz;