X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=liblttng-ust%2Flttng-ust-comm.c;h=d0641c5c6e510b01d0538d9c36b07c5c430644c6;hb=f194f3b00d042154c35f1f9ec262e25f2cd83b8a;hp=336510003a01006afb722cab4dbb056d89976fbd;hpb=8236ba105157889ebc49554b20a6c46211f1a663;p=lttng-ust.git

diff --git a/liblttng-ust/lttng-ust-comm.c b/liblttng-ust/lttng-ust-comm.c
index 33651000..d0641c5c 100644
--- a/liblttng-ust/lttng-ust-comm.c
+++ b/liblttng-ust/lttng-ust-comm.c
@@ -22,7 +22,6 @@
 #define _LGPL_SOURCE
 #include <sys/types.h>
 #include <sys/socket.h>
-#include <sys/prctl.h>
 #include <sys/mman.h>
 #include <sys/stat.h>
 #include <sys/types.h>
@@ -46,6 +45,7 @@
 #include <usterr-signal-safe.h>
 #include "tracepoint-internal.h"
 #include "ltt-tracer-core.h"
+#include "compat.h"
 
 /*
  * Has lttng ust comm constructor been called ?
@@ -159,7 +159,6 @@ static
 int register_app_to_sessiond(int socket)
 {
 	ssize_t ret;
-	int prctl_ret;
 	struct {
 		uint32_t major;
 		uint32_t minor;
@@ -178,11 +177,7 @@ int register_app_to_sessiond(int socket)
 	reg_msg.uid = getuid();
 	reg_msg.gid = getgid();
 	reg_msg.bits_per_long = CAA_BITS_PER_LONG;
-	prctl_ret = prctl(PR_GET_NAME, (unsigned long) reg_msg.name, 0, 0, 0);
-	if (prctl_ret) {
-		ERR("Error executing prctl");
-		return -errno;
-	}
+	lttng_ust_getprocname(reg_msg.name);
 
 	ret = ustcomm_send_unix_sock(socket, &reg_msg, sizeof(reg_msg));
 	if (ret >= 0 && ret != sizeof(reg_msg))
@@ -239,6 +234,7 @@ int handle_message(struct sock_info *sock_info,
 	const struct lttng_ust_objd_ops *ops;
 	struct ustcomm_ust_reply lur;
 	int shm_fd, wait_fd;
+	union ust_args args;
 
 	ust_lock();
 
@@ -271,7 +267,8 @@ int handle_message(struct sock_info *sock_info,
 	default:
 		if (ops->cmd)
 			ret = ops->cmd(lum->handle, lum->cmd,
-					(unsigned long) &lum->u);
+					(unsigned long) &lum->u,
+					&args);
 		else
 			ret = -ENOSYS;
 		break;
@@ -293,23 +290,21 @@ end:
 		 * Special-case reply to send stream info.
 		 * Use lum.u output.
 		 */
-		lur.u.stream.memory_map_size = lum->u.stream.memory_map_size;
-		shm_fd = lum->u.stream.shm_fd;
-		wait_fd = lum->u.stream.wait_fd;
+		lur.u.stream.memory_map_size = *args.stream.memory_map_size;
+		shm_fd = *args.stream.shm_fd;
+		wait_fd = *args.stream.wait_fd;
 		break;
 	case LTTNG_UST_METADATA:
 	case LTTNG_UST_CHANNEL:
-		lur.u.channel.memory_map_size = lum->u.channel.memory_map_size;
-		shm_fd = lum->u.channel.shm_fd;
-		wait_fd = lum->u.channel.wait_fd;
+		lur.u.channel.memory_map_size = *args.channel.memory_map_size;
+		shm_fd = *args.channel.shm_fd;
+		wait_fd = *args.channel.wait_fd;
 		break;
 	case LTTNG_UST_TRACER_VERSION:
 		lur.u.version = lum->u.version;
 		break;
 	case LTTNG_UST_TRACEPOINT_LIST_GET:
-		memcpy(lur.u.tracepoint_list_entry,
-			lum->u.tracepoint_list_entry,
-			LTTNG_UST_SYM_NAME_LEN);
+		memcpy(&lur.u.tracepoint, &lum->u.tracepoint, sizeof(lur.u.tracepoint));
 		break;
 	}
 	ret = send_reply(sock, &lur);
@@ -338,6 +333,50 @@ end:
 			goto error;
 		}
 	}
+	/*
+	 * We still have the memory map reference, and the fds have been
+	 * sent to the sessiond. We can therefore close those fds. Note
+	 * that we keep the write side of the wait_fd open, but close
+	 * the read side.
+	 */
+	if (lur.ret_code == USTCOMM_OK) {
+		switch (lum->cmd) {
+		case LTTNG_UST_STREAM:
+			if (shm_fd >= 0) {
+				ret = close(shm_fd);
+				if (ret) {
+					PERROR("Error closing stream shm_fd");
+				}
+				*args.stream.shm_fd = -1;
+			}
+			if (wait_fd >= 0) {
+				ret = close(wait_fd);
+				if (ret) {
+					PERROR("Error closing stream wait_fd");
+				}
+				*args.stream.wait_fd = -1;
+			}
+			break;
+		case LTTNG_UST_METADATA:
+		case LTTNG_UST_CHANNEL:
+			if (shm_fd >= 0) {
+				ret = close(shm_fd);
+				if (ret) {
+					PERROR("Error closing channel shm_fd");
+				}
+				*args.channel.shm_fd = -1;
+			}
+			if (wait_fd >= 0) {
+				ret = close(wait_fd);
+				if (ret) {
+					PERROR("Error closing channel wait_fd");
+				}
+				*args.channel.wait_fd = -1;
+			}
+			break;
+		}
+	}
+
 error:
 	ust_unlock();
 	return ret;
@@ -415,7 +454,7 @@ int get_wait_shm(struct sock_info *sock_info, size_t mmap_size)
 		 * shared memory map will have been created.
 		 */
 		pid = wait(&status);
-		if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) {
+		if (pid < 0 || !WIFEXITED(status) || WEXITSTATUS(status) != 0) {
 			wait_shm_fd = -1;
 			goto end;
 		}
@@ -563,14 +602,15 @@ void wait_for_sessiond(struct sock_info *sock_info)
 		if (ret < 0) {
 			if (errno == EFAULT) {
 				wait_poll_fallback = 1;
-				WARN(
+				DBG(
 "Linux kernels 2.6.33 to 3.0 (with the exception of stable versions) "
 "do not support FUTEX_WAKE on read-only memory mappings correctly. "
 "Please upgrade your kernel "
 "(fix is commit 9ea71503a8ed9184d2d0b8ccc4d269d05f7940ae in Linux kernel "
 "mainline). LTTng-UST will use polling mode fallback.");
+				if (ust_debug())
+					PERROR("futex");
 			}
-			PERROR("futex");
 		}
 	}
 	return;