diff --git a/tools/perf/builtin-inject.c b/tools/perf/builtin-inject.c
index ddccc0eb7390..6007f1844b01 100644
--- a/tools/perf/builtin-inject.c
+++ b/tools/perf/builtin-inject.c
@@ -43,6 +43,8 @@ struct perf_inject {
 	bool			have_auxtrace;
 	bool			strip;
 	bool			jit_mode;
+	bool			in_place_update;
+	bool			in_place_update_dry_run;
 	const char		*input_name;
 	struct perf_data	output;
 	u64			bytes_written;
@@ -701,7 +703,7 @@ static int __cmd_inject(struct perf_inject *inject)
 	int ret = -EINVAL;
 	struct perf_session *session = inject->session;
 	struct perf_data *data_out = &inject->output;
-	int fd = perf_data__fd(data_out);
+	int fd = inject->in_place_update ? -1 : perf_data__fd(data_out);
 	u64 output_data_offset;
 
 	signal(SIGINT, sig_handler);
@@ -759,14 +761,14 @@ static int __cmd_inject(struct perf_inject *inject)
 	if (!inject->itrace_synth_opts.set)
 		auxtrace_index__free(&session->auxtrace_index);
 
-	if (!data_out->is_pipe)
+	if (!data_out->is_pipe && !inject->in_place_update)
 		lseek(fd, output_data_offset, SEEK_SET);
 
 	ret = perf_session__process_events(session);
 	if (ret)
 		return ret;
 
-	if (!data_out->is_pipe) {
+	if (!data_out->is_pipe && !inject->in_place_update) {
 		if (inject->build_ids)
 			perf_header__set_feat(&session->header,
 					      HEADER_BUILD_ID);
@@ -900,7 +902,23 @@ int cmd_inject(int argc, const char **argv)
 		return -1;
 	}
 
-	if (perf_data__open(&inject.output)) {
+	if (inject.in_place_update) {
+		if (!strcmp(inject.input_name, "-")) {
+			pr_err("Input file name required for in-place updating\n");
+			return -1;
+		}
+		if (strcmp(inject.output.path, "-")) {
+			pr_err("Output file name must not be specified for in-place updating\n");
+			return -1;
+		}
+		if (!data.force && !inject.in_place_update_dry_run) {
+			pr_err("The input file would be updated in place, "
+				"the --force option is required.\n");
+			return -1;
+		}
+		if (!inject.in_place_update_dry_run)
+			data.in_place_update = true;
+	} else if (perf_data__open(&inject.output)) {
 		perror("failed to create output file");
 		return -1;
 	}
diff --git a/tools/perf/util/data.c b/tools/perf/util/data.c
index 8fca4779ae6a..a9c102e8e3c0 100644
--- a/tools/perf/util/data.c
+++ b/tools/perf/util/data.c
@@ -240,11 +240,12 @@ static bool is_dir(struct perf_data *data)
 
 static int open_file_read(struct perf_data *data)
 {
+	int flags = data->in_place_update ? O_RDWR : O_RDONLY;
 	struct stat st;
 	int fd;
 	char sbuf[STRERR_BUFSIZE];
 
-	fd = open(data->file.path, O_RDONLY);
+	fd = open(data->file.path, flags);
 	if (fd < 0) {
 		int err = errno;
 
diff --git a/tools/perf/util/data.h b/tools/perf/util/data.h
index 62a3e66fbee8..c9de82af5584 100644
--- a/tools/perf/util/data.h
+++ b/tools/perf/util/data.h
@@ -31,6 +31,7 @@ struct perf_data {
 	bool			 is_dir;
 	bool			 force;
 	bool			 use_stdio;
+	bool			 in_place_update;
 	enum perf_data_mode	 mode;
 
 	struct {
diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index aa1e42518d37..02b13c7a23be 100644
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -3814,6 +3814,11 @@ int perf_session__read_header(struct perf_session *session)
 	if (perf_file_header__read(&f_header, header, fd) < 0)
 		return -EINVAL;
 
+	if (header->needs_swap && data->in_place_update) {
+		pr_err("In-place update not supported when byte-swapping is required\n");
+		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.
diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
index 106b3d60881a..0dbb4f2628f3 100644
--- a/tools/perf/util/session.c
+++ b/tools/perf/util/session.c
@@ -2155,6 +2155,7 @@ struct reader {
 	u64		 data_size;
 	u64		 data_offset;
 	reader_cb_t	 process;
+	bool		 in_place_update;
 };
 
 static int
@@ -2188,7 +2189,9 @@ reader__process_events(struct reader *rd, struct perf_session *session,
 	mmap_prot  = PROT_READ;
 	mmap_flags = MAP_SHARED;
 
-	if (session->header.needs_swap) {
+	if (rd->in_place_update) {
+		mmap_prot  |= PROT_WRITE;
+	} else if (session->header.needs_swap) {
 		mmap_prot  |= PROT_WRITE;
 		mmap_flags = MAP_PRIVATE;
 	}
@@ -2274,6 +2277,7 @@ static int __perf_session__process_events(struct perf_session *session)
 		.data_size	= session->header.data_size,
 		.data_offset	= session->header.data_offset,
 		.process	= process_simple,
+		.in_place_update = session->data->in_place_update,
 	};
 	struct ordered_events *oe = &session->ordered_events;
 	struct perf_tool *tool = session->tool;