Commit 40db8ff5 authored by Adrian Hunter's avatar Adrian Hunter Committed by Arnaldo Carvalho de Melo
Browse files

perf tools: Handle read errors from ctl_fd 



Handle read errors from ctl_fd such as EINTR, EAGAIN and EWOULDBLOCK.

Signed-off-by: default avatarAdrian Hunter <adrian.hunter@intel.com>
Acked-by: default avatarAlexey Budankov <alexey.budankov@linux.intel.com>
Acked-by: default avatarJiri Olsa <jolsa@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: http://lore.kernel.org/lkml/20200901093758.32293-3-adrian.hunter@intel.com


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent 9864a66d

tools/perf/util/evlist.c

+11 −5
Original line number Diff line number Diff line
@@ -1802,6 +1802,7 @@ static int evlist__ctlfd_recv(struct evlist *evlist, enum evlist_ctl_cmd *cmd, 
	char c;

	size_t bytes_read = 0;



	*cmd = EVLIST_CTL_CMD_UNSUPPORTED;

	memset(cmd_data, 0, data_size);

	data_size--;
@@ -1813,17 +1814,22 @@ static int evlist__ctlfd_recv(struct evlist *evlist, enum evlist_ctl_cmd *cmd, 
			cmd_data[bytes_read++] = c;

			if (bytes_read == data_size)

				break;

		} else {

			if (err == -1)

			continue;

		} else if (err == -1) {

			if (errno == EINTR)

				continue;

			if (errno == EAGAIN || errno == EWOULDBLOCK)

				err = 0;

			else

				pr_err("Failed to read from ctlfd %d: %m\n", evlist->ctl_fd.fd);

			break;

		}

		break;

	} while (1);



	pr_debug("Message from ctl_fd: \"%s%s\"\n", cmd_data,

		 bytes_read == data_size ? "" : c == '\n' ? "\\n" : "\\0");



	if (err > 0) {

	if (bytes_read > 0) {

		if (!strncmp(cmd_data, EVLIST_CTL_CMD_ENABLE_TAG,

			     (sizeof(EVLIST_CTL_CMD_ENABLE_TAG)-1))) {

			*cmd = EVLIST_CTL_CMD_ENABLE;
@@ -1833,7 +1839,7 @@ static int evlist__ctlfd_recv(struct evlist *evlist, enum evlist_ctl_cmd *cmd, 
		}

	}



	return err;

	return bytes_read ? (int)bytes_read : err;

}



static int evlist__ctlfd_ack(struct evlist *evlist)