[ltt-dev] Make lttctl use new interface

Mathieu Desnoyers compudj at krystal.dyndns.org
Fri Nov 28 07:38:50 EST 2008


* Zhaolei (zhaolei at cn.fujitsu.com) wrote:
> Hi, Mathieu
> 
> I modified lttctl for support debugfs-based ltt-trace-control.
> 
> This patch only modified interior method of control ltt trace,
> so command args are not changed.
> 
> We can use this code without modify our user-manual, and lttv need not change
> too.
> 
> But personaly, I'd like to design a set of new command arguments for lttctl in
> next step, for support each-channel buffer and overwrite control.
> And old cmd-args as -X, -V, -B, -z, -x, -v may be dropped(or change for easy
> to remember)
> For example:
> -c Create a trace
> -C Create a trace and start
> -d Destroy trace channels
> -D Stop and destroy trace channels
> ...
> or
> -c  Create a trace
> -cs Create a trace and start
> -d  Destroy trace channels
> -td Terminate and destroy trace channels
> ...
> But it we do, our unlucky users must read our new manual again : (
> What is your opinion?
> 

Your patch looks great :) But I'd go directly for a command-line
breakage so we don't end up keeping legacy options. The sooner the
better.

I really like the -c, -C, -d, -D approach. Maybe we could have both of
your suggestions supported as aliases ?

If we change this, we should also update the lttv QUICKSTART file
accordingly.

Mathieu


> Signed-off-by: Zhao Lei <zhaolei at cn.fujitsu.com>
> ---
> diff -Nur ltt-control-0.58-23112008.org/liblttctl/liblttctl.c ltt-control-0.58-23112008/liblttctl/liblttctl.c
> --- ltt-control-0.58-23112008.org/liblttctl/liblttctl.c	2008-11-28 15:08:35.000000000 +0800
> +++ ltt-control-0.58-23112008/liblttctl/liblttctl.c	2008-11-28 15:08:35.000000000 +0800
> @@ -2,10 +2,7 @@
>   *
>   * Linux Trace Toolkit Netlink Control Library
>   *
> - * Controls the ltt-control kernel module through a netlink socket.
> - *
> - * Heavily inspired from libipq.c (iptables) made by 
> - * James Morris <jmorris at intercode.com.au>
> + * Controls the ltt-control kernel module through debugfs.
>   *
>   * Copyright 2005 -
>   * 	Mathieu Desnoyers <mathieu.desnoyers at polymtl.ca>
> @@ -20,7 +17,7 @@
>   * but WITHOUT ANY WARRANTY; without even the implied warranty of
>   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	See the
>   * GNU General Public License for more details.
> - * 	
> + *
>   */
>  
>  #ifdef HAVE_CONFIG_H
> @@ -30,462 +27,557 @@
>  #include <liblttctl/lttctl.h>
>  #include <errno.h>
>  #include <stdio.h>
> -#include <error.h>
> -#include <stdlib.h>
> -#include <sys/types.h>
> -#include <unistd.h>
>  #include <string.h>
> +#include <dirent.h>
> +#include <limits.h>
> +#include <fcntl.h>
> +
> +struct chan_info_struct {
> +	const char *name;
> +	int buf_type; /* 0: low 1: med 2: high */
> +} chan_infos[] = {
> +	{"cpu", 2},
> +	{"processes", 1},
> +	{"interrupts", 0},
> +	{"network", 0},
> +	{"modules", 0},
> +	{"metadata", 0},
> +};
>  
> +static char debugfsmntdir[PATH_MAX];
> +static int initdebugfsmntdir(void)
> +{
> +	char mnt_dir[PATH_MAX];
> +	char mnt_type[PATH_MAX];
>  
> +	FILE *fp = fopen("/proc/mounts", "r");
> +	if (!fp) {
> +		fprintf(stderr, "%s: Can't open /proc/mounts\n", __func__);
> +		return 1;
> +	}
> +
> +	while (1) {
> +		if (fscanf(fp, "%*s %s %s %*s %*s %*s", mnt_dir, mnt_type)
> +			<= 0) {
> +			fprintf(stderr, "%s: debugfs mountpoint not found\n",
> +				__func__);
> +			return 1;
> +		}
> +		if (!strcmp(mnt_type, "debugfs")) {
> +			strcpy(debugfsmntdir, mnt_dir);
> +			return 0;
> +		}
> +	}
> +}
>  
> -/* Private interface */
> +int lttctl_init(void)
> +{
> +	int ret;
> +	DIR *dir;
> +	char controldirname[PATH_MAX];
>  
> -enum {
> -	LTTCTL_ERR_NONE = 0,
> -	LTTCTL_ERR_IMPL,
> -	LTTCTL_ERR_HANDLE,
> -	LTTCTL_ERR_SOCKET,
> -	LTTCTL_ERR_BIND,
> -	LTTCTL_ERR_BUFFER,
> -	LTTCTL_ERR_RECV,
> -	LTTCTL_ERR_NLEOF,
> -	LTTCTL_ERR_ADDRLEN,
> -	LTTCTL_ERR_STRUNC,
> -	LTTCTL_ERR_RTRUNC,
> -	LTTCTL_ERR_NLRECV,
> -	LTTCTL_ERR_SEND,
> -	LTTCTL_ERR_SUPP,
> -	LTTCTL_ERR_RECVBUF,
> -	LTTCTL_ERR_TIMEOUT,
> -	LTTCTL_ERR_PROTOCOL,
> -};
> -#define LTTCTL_MAXERR LTTCTL_ERR_PROTOCOL
> +	ret = initdebugfsmntdir();
> +	if (ret) {
> +		fprintf(stderr, "Debugfs mount point not found\n");
> +		return 1;
> +	}
>  
> +	/* check ltt control's debugfs dir */
> +	sprintf(controldirname, "%s/ltt/control/", debugfsmntdir);
>  
> -struct lttctl_errmap_t {
> -	int errcode;
> -	char *message;
> -} lttctl_errmap[] = {
> -	{ LTTCTL_ERR_NONE, "Unknown error" },
> -	{ LTTCTL_ERR_IMPL, "Implementation error" },
> -	{ LTTCTL_ERR_HANDLE, "Unable to create netlink handle" },
> -	{ LTTCTL_ERR_SOCKET, "Unable to create netlink socket" },
> -	{ LTTCTL_ERR_BIND, "Unable to bind netlink socket" },
> -	{ LTTCTL_ERR_BUFFER, "Unable to allocate buffer" },
> -	{ LTTCTL_ERR_RECV, "Failed to receive netlink message" },
> -	{ LTTCTL_ERR_NLEOF, "Received EOF on netlink socket" },
> -	{ LTTCTL_ERR_ADDRLEN, "Invalid peer address length" },
> -	{ LTTCTL_ERR_STRUNC, "Sent message truncated" },
> -	{ LTTCTL_ERR_RTRUNC, "Received message truncated" },
> -	{ LTTCTL_ERR_NLRECV, "Received error from netlink" },
> -	{ LTTCTL_ERR_SEND, "Failed to send netlink message" },
> -	{ LTTCTL_ERR_SUPP, "Operation not supported" },
> -	{ LTTCTL_ERR_RECVBUF, "Receive buffer size invalid" },
> -	{ LTTCTL_ERR_TIMEOUT, "Timeout"},
> -	{ LTTCTL_ERR_PROTOCOL, "Invalid protocol specified" }
> -};
> +	dir = opendir(controldirname);
> +	if (!dir) {
> +		fprintf(stderr, "ltt-trace-control's debugfs dir not found\n");
> +		closedir(dir);
> +		return -errno;
> +	}
>  
> -static int lttctl_errno = LTTCTL_ERR_NONE;
> +	closedir(dir);
>  
> +	return 0;
> +}
>  
> -static ssize_t lttctl_netlink_sendto(const struct lttctl_handle *h,
> -																	const void *msg, size_t len);
> +int lttctl_destroy(void)
> +{
> +	return 0;
> +}
>  
> -static ssize_t lttctl_netlink_recvfrom(const struct lttctl_handle *h,
> -																		unsigned char *buf, size_t len,
> -																		int timeout);
> +static int lttctl_sendop(const char *fname, const char *op)
> +{
> +	int fd;
>  
> -static ssize_t lttctl_netlink_sendmsg(const struct lttctl_handle *h,
> -																	 const struct msghdr *msg,
> -																	 unsigned int flags);
> +	if (!fname) {
> +		fprintf(stderr, "%s: args invalid\n", __func__);
> +		return 1;
> +	}
>  
> -static char *lttctl_strerror(int errcode);
> +	fd = open(fname, O_WRONLY);
> +	if (fd == -1) {
> +		fprintf(stderr, "%s: open %s failed: %s\n", __func__, fname,
> +			strerror(errno));
> +		return errno;
> +	}
>  
> -void lttctl_perror(const char *s);
> +	if (write(fd, op, strlen(op)) == -1) {
> +		fprintf(stderr, "%s: write %s to %s failed: %s\n", __func__, op,
> +			fname, strerror(errno));
> +		close(fd);
> +		return 1;
> +	}
>  
> -static ssize_t lttctl_netlink_sendto(const struct lttctl_handle *h,
> -																	const void *msg, size_t len)
> -{
> -	int status = sendto(h->fd, msg, len, 0,
> -			(struct sockaddr *)&h->peer, sizeof(h->peer));
> -	if (status < 0)
> -		lttctl_errno = LTTCTL_ERR_SEND;
> -	
> -	return status;
> -}
> +	close(fd);
>  
> -static ssize_t lttctl_netlink_sendmsg(const struct lttctl_handle *h,
> -																	 const struct msghdr *msg,
> -																	 unsigned int flags)
> -{
> -	int status = sendmsg(h->fd, msg, flags);
> -	if (status < 0)
> -		lttctl_errno = LTTCTL_ERR_SEND;
> -	return status;
> +	return 0;
>  }
>  
> -static ssize_t lttctl_netlink_recvfrom(const struct lttctl_handle *h,
> -																		unsigned char *buf, size_t len,
> -																		int timeout)
> +/*
> + * check is trace exist(check debugfsmntdir too)
> + * expect:
> + *   0: expect that trace not exist
> + *   !0: expect that trace exist
> + *
> + * ret:
> + *   0: check pass
> + *   1: check failed
> + *   -ERRNO: error happened (no check)
> + */
> +static int lttctl_check_trace(const char *name, int expect)
>  {
> -	int addrlen, status;
> -	struct nlmsghdr *nlh;
> +	char tracedirname[PATH_MAX];
> +	DIR *dir;
> +	int exist;
>  
> -	if (len < sizeof(struct nlmsghdr)) {
> -		lttctl_errno = LTTCTL_ERR_RECVBUF;
> -		lttctl_perror("Netlink recvfrom");
> -		return -1;
> +	if (!name) {
> +		fprintf(stderr, "%s: args invalid\n", __func__);
> +		return -EINVAL;
>  	}
> -	addrlen = sizeof(h->peer);
>  
> -	if (timeout != 0) {
> -		int ret;
> -		struct timeval tv;
> -		fd_set read_fds;
> -		
> -		if (timeout < 0) {
> -			/* non-block non-timeout */
> -			tv.tv_sec = 0;
> -			tv.tv_usec = 0;
> -		} else {
> -			tv.tv_sec = timeout / 1000000;
> -			tv.tv_usec = timeout % 1000000;
> -		}
> +	if (!debugfsmntdir[0]) {
> +		fprintf(stderr, "%s: debugfsmntdir not valid\n", __func__);
> +		return -EINVAL;
> +	}
>  
> -		FD_ZERO(&read_fds);
> -		FD_SET(h->fd, &read_fds);
> -		ret = select(h->fd+1, &read_fds, NULL, NULL, &tv);
> -		if (ret < 0) {
> -			if (errno == EINTR) {
> -				printf("eintr\n");
> -				return 0;
> -			} else {
> -				lttctl_errno = LTTCTL_ERR_RECV;
> -				lttctl_perror("Netlink recvfrom");
> -				return -1;
> -			}
> -		}
> -		if (!FD_ISSET(h->fd, &read_fds)) {
> -			lttctl_errno = LTTCTL_ERR_TIMEOUT;
> -			printf("timeout\n");
> -			return 0;
> +	sprintf(tracedirname, "%s/ltt/control/%s", debugfsmntdir, name);
> +
> +	dir = opendir(tracedirname);
> +	if (dir) {
> +		exist = 1;
> +	} else {
> +		if (errno != ENOENT) {
> +			fprintf(stderr, "%s: %s\n", __func__, strerror(errno));
> +			return -EINVAL;
>  		}
> +		exist = 0;
>  	}
> -	status = recvfrom(h->fd, buf, len, 0,
> -			(struct sockaddr *)&h->peer, &addrlen);
> -	
> -	if (status < 0) {
> -		lttctl_errno = LTTCTL_ERR_RECV;
> -		lttctl_perror("Netlink recvfrom");
> -		return status;
> +
> +	closedir(dir);
> +
> +	if (!expect != !exist) {
> +		if (exist)
> +			fprintf(stderr, "Trace %s already exist\n", name);
> +		else
> +			fprintf(stderr, "Trace %s not exist\n", name);
> +		return 1;
>  	}
> -	if (addrlen != sizeof(h->peer)) {
> -		lttctl_errno = LTTCTL_ERR_RECV;
> -		lttctl_perror("Netlink recvfrom");
> -		return -1;
> +
> +	return 0;
> +}
> +
> +int lttctl_setup_trace(const char *name)
> +{
> +	int ret;
> +	char ctlfname[PATH_MAX];
> +
> +	if (!name) {
> +		fprintf(stderr, "%s: args invalid\n", __func__);
> +		ret = -EINVAL;
> +		goto arg_error;
>  	}
> -	if (h->peer.nl_pid != 0) {
> -		lttctl_errno = LTTCTL_ERR_RECV;
> -		lttctl_perror("Netlink recvfrom");
> -		return -1;
> +
> +	ret = lttctl_check_trace(name, 0);
> +	if (ret)
> +		goto arg_error;
> +
> +	sprintf(ctlfname, "%s/ltt/setup_trace", debugfsmntdir);
> +
> +	ret = lttctl_sendop(ctlfname, name);
> +	if (ret) {
> +		fprintf(stderr, "Setup trace failed\n");
> +		goto op_err;
>  	}
> -	if (status == 0) {
> -		lttctl_errno = LTTCTL_ERR_NLEOF;
> -		lttctl_perror("Netlink recvfrom");
> -		return -1;
> +
> +	return 0;
> +
> +op_err:
> +arg_error:
> +	return ret;
> +}
> +
> +int lttctl_destroy_trace(const char *name)
> +{
> +	int ret;
> +	char ctlfname[PATH_MAX];
> +
> +	if (!name) {
> +		fprintf(stderr, "%s: args invalid\n", __func__);
> +		ret = -EINVAL;
> +		goto arg_error;
>  	}
> -	nlh = (struct nlmsghdr *)buf;
> -	if (nlh->nlmsg_flags & MSG_TRUNC || nlh->nlmsg_len > status) {
> -		lttctl_errno = LTTCTL_ERR_RTRUNC;
> -		lttctl_perror("Netlink recvfrom");
> -		return -1;
> +
> +	ret = lttctl_check_trace(name, 1);
> +	if (ret)
> +		goto arg_error;
> +
> +	sprintf(ctlfname, "%s/ltt/destroy_trace", debugfsmntdir);
> +
> +	ret = lttctl_sendop(ctlfname, name);
> +	if (ret) {
> +		fprintf(stderr, "Destroy trace failed\n");
> +		goto op_err;
>  	}
> -	
>  
> -	return status;
> -}
> +	return 0;
>  
> +op_err:
> +arg_error:
> +	return ret;
> +}
>  
> -static char *lttctl_strerror(int errcode)
> +int lttctl_alloc_trace(const char *name)
>  {
> -	if (errcode < 0 || errcode > LTTCTL_MAXERR)
> -		errcode = LTTCTL_ERR_IMPL;
> -	return lttctl_errmap[errcode].message;
> -}
> +	int ret;
> +	char ctlfname[PATH_MAX];
> +
> +	if (!name) {
> +		fprintf(stderr, "%s: args invalid\n", __func__);
> +		ret = -EINVAL;
> +		goto arg_error;
> +	}
>  
> +	ret = lttctl_check_trace(name, 1);
> +	if (ret)
> +		goto arg_error;
>  
> -char *lttctl_errstr(void)
> -{
> -	return lttctl_strerror(lttctl_errno);
> +	sprintf(ctlfname, "%s/ltt/control/%s/alloc", debugfsmntdir, name);
> +
> +	ret = lttctl_sendop(ctlfname, "1");
> +	if (ret) {
> +		fprintf(stderr, "Allocate trace failed\n");
> +		goto op_err;
> +	}
> +
> +	return 0;
> +
> +op_err:
> +arg_error:
> +	return ret;
>  }
>  
> -void lttctl_perror(const char *s)
> +int lttctl_start(const char *name)
>  {
> -	if (s)
> -		fputs(s, stderr);
> -	else
> -		fputs("ERROR", stderr);
> -	if (lttctl_errno)
> -		fprintf(stderr, ": %s", lttctl_errstr());
> -	if (errno)
> -		fprintf(stderr, ": %s", strerror(-errno));
> -	fputc('\n', stderr);
> -}
> +	int ret;
> +	char ctlfname[PATH_MAX];
>  
> -/* public interface */
> +	if (!name) {
> +		fprintf(stderr, "%s: args invalid\n", __func__);
> +		ret = -EINVAL;
> +		goto arg_error;
> +	}
>  
> -/*
> - * Create and initialise an lttctl handle.
> - */
> -struct lttctl_handle *lttctl_create_handle(void)
> -{
> -	int status;
> -	struct lttctl_handle *h;
> +	ret = lttctl_check_trace(name, 1);
> +	if (ret)
> +		goto arg_error;
> +
> +	sprintf(ctlfname, "%s/ltt/control/%s/enabled", debugfsmntdir, name);
>  
> -	h = (struct lttctl_handle *)malloc(sizeof(struct lttctl_handle));
> -	if (h == NULL) {
> -		lttctl_errno = LTTCTL_ERR_HANDLE;
> -		lttctl_perror("Create handle");
> -		goto alloc_error;
> -	}
> -	
> -	memset(h, 0, sizeof(struct lttctl_handle));
> -	
> -	h->fd = socket(PF_NETLINK, SOCK_RAW, NETLINK_LTT);
> -				
> -	if (h->fd == -1) {
> -		lttctl_errno = LTTCTL_ERR_SOCKET;
> -		lttctl_perror("Create handle");
> -		goto socket_error;
> -	}
> -	memset(&h->local, 0, sizeof(struct sockaddr_nl));
> -	h->local.nl_family = AF_NETLINK;
> -	h->local.nl_pid = getpid();
> -	h->local.nl_groups = 0;
> -	status = bind(h->fd, (struct sockaddr *)&h->local, sizeof(h->local));
> -	if (status == -1) {
> -		lttctl_errno = LTTCTL_ERR_BIND;
> -		lttctl_perror("Create handle");
> -		goto bind_error;
> -	}
> -	memset(&h->peer, 0, sizeof(struct sockaddr_nl));
> -	h->peer.nl_family = AF_NETLINK;
> -	h->peer.nl_pid = 0;
> -	h->peer.nl_groups = 0;
> -	return h;
> -	
> -	/* Error condition */
> -bind_error:
> -socket_error:
> -		close(h->fd);
> -alloc_error:
> -		free(h);
> -	return NULL;
> +	ret = lttctl_sendop(ctlfname, "1");
> +	if (ret) {
> +		fprintf(stderr, "Start trace failed\n");
> +		goto op_err;
> +	}
> +
> +	return 0;
> +
> +op_err:
> +arg_error:
> +	return ret;
>  }
>  
> -/*
> - * No error condition is checked here at this stage, but it may happen
> - * if/when reliable messaging is implemented.
> - */
> -int lttctl_destroy_handle(struct lttctl_handle *h)
> +int lttctl_stop(const char *name)
>  {
> -	if (h) {
> -		close(h->fd);
> -		free(h);
> +	int ret;
> +	char ctlfname[PATH_MAX];
> +
> +	if (!name) {
> +		fprintf(stderr, "%s: args invalid\n", __func__);
> +		ret = -EINVAL;
> +		goto arg_error;
>  	}
> +
> +	ret = lttctl_check_trace(name, 1);
> +	if (ret)
> +		goto arg_error;
> +
> +	sprintf(ctlfname, "%s/ltt/control/%s/enabled", debugfsmntdir, name);
> +
> +	ret = lttctl_sendop(ctlfname, "0");
> +	if (ret) {
> +		fprintf(stderr, "Stop trace failed\n");
> +		goto op_err;
> +	}
> +
>  	return 0;
> -}
>  
> +op_err:
> +arg_error:
> +	return ret;
> +}
>  
> -int lttctl_create_trace(const struct lttctl_handle *h,
> -		char *name, enum trace_mode mode, char *trace_type,
> -		unsigned subbuf_size_low, unsigned n_subbufs_low,
> -		unsigned subbuf_size_med, unsigned n_subbufs_med,
> -		unsigned subbuf_size_high, unsigned n_subbufs_high)
> +int lttctl_set_trans(const char *name, const char *trans)
>  {
> -	int err;
> -	
> -	struct {
> -		struct nlmsghdr	nlh;
> -		lttctl_peer_msg_t	msg;
> -	} req;
> -	struct {
> -		struct nlmsghdr	nlh;
> -		struct nlmsgerr	nlerr;
> -		lttctl_peer_msg_t	msg;
> -	} ack;
> +	int ret;
> +	char ctlfname[PATH_MAX];
>  
> -	memset(&req, 0, sizeof(req));
> -	req.nlh.nlmsg_len = NLMSG_LENGTH(sizeof(lttctl_peer_msg_t));
> -	req.nlh.nlmsg_flags = NLM_F_REQUEST|NLM_F_ACK;
> -	req.nlh.nlmsg_type = LTTCTLM_CONTROL;
> -	req.nlh.nlmsg_pid = h->local.nl_pid;
> -	req.nlh.nlmsg_seq = 0;
> -
> -	strncpy(req.msg.trace_name, name, NAME_MAX);
> -	strncpy(req.msg.trace_type, trace_type, NAME_MAX);
> -	req.msg.op = OP_CREATE;
> -	req.msg.args.new_trace.mode = mode;
> -	req.msg.args.new_trace.subbuf_size_low = subbuf_size_low;
> -	req.msg.args.new_trace.n_subbufs_low = n_subbufs_low;
> -	req.msg.args.new_trace.subbuf_size_med = subbuf_size_med;
> -	req.msg.args.new_trace.n_subbufs_med = n_subbufs_med;
> -	req.msg.args.new_trace.subbuf_size_high = subbuf_size_high;
> -	req.msg.args.new_trace.n_subbufs_high = n_subbufs_high;
> +	if (!name) {
> +		fprintf(stderr, "%s: args invalid\n", __func__);
> +		ret = -EINVAL;
> +		goto arg_error;
> +	}
>  
> -	err = lttctl_netlink_sendto(h, (void *)&req, req.nlh.nlmsg_len);
> -	if(err < 0) goto senderr;
> +	ret = lttctl_check_trace(name, 1);
> +	if (ret)
> +		goto arg_error;
>  
> -	err = lttctl_netlink_recvfrom(h, (void*)&ack, sizeof(ack), 0);
> -	if(err < 0) goto senderr;
> +	sprintf(ctlfname, "%s/ltt/control/%s/trans", debugfsmntdir, name);
>  
> -	err = ack.nlerr.error;
> -	if(err != 0) {
> -		errno = err;
> -		lttctl_perror("Create Trace Error");
> -		return err;
> +	ret = lttctl_sendop(ctlfname, trans);
> +	if (ret) {
> +		fprintf(stderr, "Set transport failed\n");
> +		goto op_err;
>  	}
>  
>  	return 0;
>  
> -senderr:
> -	lttctl_perror("Create Trace Error");
> -	err = EPERM;
> -	return err;
> +op_err:
> +arg_error:
> +	return ret;
>  }
>  
> -int lttctl_destroy_trace(const struct lttctl_handle *h,
> -		char *name)
> +int lttctl_set_channel_overwrite(const char *name, const char *channel,
> +		int overwrite)
>  {
> -	struct {
> -		struct nlmsghdr	nlh;
> -		lttctl_peer_msg_t	msg;
> -	} req;
> -	struct {
> -		struct nlmsghdr	nlh;
> -		struct nlmsgerr	nlerr;
> -		lttctl_peer_msg_t	msg;
> -	} ack;
> -	int err;
> +	int ret;
> +	char ctlfname[PATH_MAX];
>  
> -	memset(&req, 0, sizeof(req));
> -	req.nlh.nlmsg_len = NLMSG_LENGTH(sizeof(lttctl_peer_msg_t));
> -	req.nlh.nlmsg_flags = NLM_F_REQUEST;
> -	req.nlh.nlmsg_type = LTTCTLM_CONTROL;
> -	req.nlh.nlmsg_pid = h->local.nl_pid;
> -
> -	strncpy(req.msg.trace_name, name, NAME_MAX);
> -	req.msg.op = OP_DESTROY;
> +	if (!name || !channel) {
> +		fprintf(stderr, "%s: args invalid\n", __func__);
> +		ret = -EINVAL;
> +		goto arg_error;
> +	}
>  
> -	err = lttctl_netlink_sendto(h, (void *)&req, req.nlh.nlmsg_len);
> -	if(err < 0) goto senderr;
> +	ret = lttctl_check_trace(name, 1);
> +	if (ret)
> +		goto arg_error;
>  
> -	err = lttctl_netlink_recvfrom(h, (void*)&ack, sizeof(ack), 0);
> -	if(err < 0) goto senderr;
> +	sprintf(ctlfname, "%s/ltt/control/%s/channel/%s/subbuf_num",
> +		debugfsmntdir, name, channel);
>  
> -	err = ack.nlerr.error;
> -	if(err != 0) {
> -		errno = err;
> -		lttctl_perror("Destroy Trace Channels Error");
> -		return err;
> +	ret = lttctl_sendop(ctlfname, overwrite?"1":"0");
> +	if (ret) {
> +		fprintf(stderr, "Set channel's overwrite mode failed\n");
> +		goto op_err;
>  	}
>  
>  	return 0;
>  
> -senderr:
> -	lttctl_perror("Destroy Trace Channels Error");
> -	err = EPERM;
> -	return err;
> -
> +op_err:
> +arg_error:
> +	return ret;
>  }
>  
> -int lttctl_start(const struct lttctl_handle *h,
> -		char *name)
> +int lttctl_set_channel_subbuf_num(const char *name, const char *channel,
> +		unsigned subbuf_num)
>  {
> -	struct {
> -		struct nlmsghdr	nlh;
> -		lttctl_peer_msg_t	msg;
> -	} req;
> -	struct {
> -		struct nlmsghdr	nlh;
> -		struct nlmsgerr	nlerr;
> -		lttctl_peer_msg_t	msg;
> -	} ack;
> -
> -	int err;
> +	int ret;
> +	char ctlfname[PATH_MAX];
> +	char opstr[32];
>  
> -	memset(&req, 0, sizeof(req));
> -	req.nlh.nlmsg_len = NLMSG_LENGTH(sizeof(lttctl_peer_msg_t));
> -	req.nlh.nlmsg_flags = NLM_F_REQUEST;
> -	req.nlh.nlmsg_type = LTTCTLM_CONTROL;
> -	req.nlh.nlmsg_pid = h->local.nl_pid;
> +	if (!name || !channel) {
> +		fprintf(stderr, "%s: args invalid\n", __func__);
> +		ret = -EINVAL;
> +		goto arg_error;
> +	}
>  
> -	strncpy(req.msg.trace_name, name, NAME_MAX);
> -	req.msg.op = OP_START;
> +	ret = lttctl_check_trace(name, 1);
> +	if (ret)
> +		goto arg_error;
>  
> -	err = lttctl_netlink_sendto(h, (void *)&req, req.nlh.nlmsg_len);
> -	if(err < 0) goto senderr;
> +	sprintf(ctlfname, "%s/ltt/control/%s/channel/%s/subbuf_num",
> +		debugfsmntdir, name, channel);
>  
> -	err = lttctl_netlink_recvfrom(h, (void*)&ack, sizeof(ack), 0);
> -	if(err < 0) goto senderr;
> +	sprintf(opstr, "%u", subbuf_num);
>  
> -	err = ack.nlerr.error;
> -	if(err != 0) {
> -		errno = err;
> -		lttctl_perror("Start Trace Error");
> -		return err;
> +	ret = lttctl_sendop(ctlfname, opstr);
> +	if (ret) {
> +		fprintf(stderr, "Set channel's subbuf number failed\n");
> +		goto op_err;
>  	}
>  
>  	return 0;
>  
> -senderr:
> -	err = EPERM;
> -	lttctl_perror("Start Trace Error");
> -	return err;
> -
> +op_err:
> +arg_error:
> +	return ret;
>  }
>  
> -int lttctl_stop(const struct lttctl_handle *h,
> -		char *name)
> +int lttctl_set_channel_subbuf_size(const char *name, const char *channel,
> +		unsigned subbuf_size)
>  {
> -	struct {
> -		struct nlmsghdr	nlh;
> -		lttctl_peer_msg_t msg;
> -	} req;
> -	struct {
> -		struct nlmsghdr	nlh;
> -		struct nlmsgerr	nlerr;
> -		lttctl_peer_msg_t msg;
> -	} ack;
> -	int err;
> +	int ret;
> +	char ctlfname[PATH_MAX];
> +	char opstr[32];
>  
> -	memset(&req, 0, sizeof(req));
> -	req.nlh.nlmsg_len = NLMSG_LENGTH(sizeof(lttctl_peer_msg_t));
> -	req.nlh.nlmsg_flags = NLM_F_REQUEST;
> -	req.nlh.nlmsg_type = LTTCTLM_CONTROL;
> -	req.nlh.nlmsg_pid = h->local.nl_pid;
> +	if (!name || !channel) {
> +		fprintf(stderr, "%s: args invalid\n", __func__);
> +		ret = -EINVAL;
> +		goto arg_error;
> +	}
>  
> -	strncpy(req.msg.trace_name, name, NAME_MAX);
> -	req.msg.op = OP_STOP;
> +	ret = lttctl_check_trace(name, 1);
> +	if (ret)
> +		goto arg_error;
>  
> -	err = lttctl_netlink_sendto(h, (void *)&req, req.nlh.nlmsg_len);
> -	if(err < 0) goto senderr;
> +	sprintf(ctlfname, "%s/ltt/control/%s/channel/%s/subbuf_size",
> +		debugfsmntdir, name, channel);
>  
> -	err = lttctl_netlink_recvfrom(h, (void*)&ack, sizeof(ack), 0);
> -	if(err < 0) goto senderr;
> +	sprintf(opstr, "%u", subbuf_size);
>  
> -	err = ack.nlerr.error;
> -	if(err != 0) {
> -		errno = err;
> -		lttctl_perror("Stop Trace Error");
> -		return err;
> +	ret = lttctl_sendop(ctlfname, opstr);
> +	if (ret) {
> +		fprintf(stderr, "Set channel's subbuf size failed\n");
> +		goto op_err;
>  	}
>  
>  	return 0;
>  
> -senderr:
> -	err = EPERM;
> -	lttctl_perror("Stop Trace Error");
> -	return err;
> +op_err:
> +arg_error:
> +	return ret;
>  }
>  
> +int lttctl_create_trace(const char *name, enum trace_mode mode,
> +		const char *trace_type,
> +		unsigned subbuf_size_low, unsigned n_subbufs_low,
> +		unsigned subbuf_size_med, unsigned n_subbufs_med,
> +		unsigned subbuf_size_high, unsigned n_subbufs_high)
> +{
> +	int ret;
> +	int i;
> +
> +	if (!name || !trace_type) {
> +		fprintf(stderr, "%s: args invalid\n", __func__);
> +		ret = -EINVAL;
> +		goto arg_error;
> +	}
> +
> +	ret = lttctl_setup_trace(name);
> +	if (ret)
> +		goto setup_trace_fail;
> +
> +	switch (mode) {
> +	case LTT_TRACE_NORMAL:
> +		/* each channel's default is non-overwrite */
> +		break;
> +	case LTT_TRACE_FLIGHT:
> +		for (i = 0; i < sizeof(chan_infos) / sizeof(chan_infos[0]);
> +			i++) {
> +			if (strcmp(chan_infos[i].name, "metadata") == 0)
> +				continue;
> +
> +			ret = lttctl_set_channel_overwrite(name,
> +				chan_infos[i].name, 1);
> +			if (ret)
> +				goto set_overwrite_fail;
> +		}
> +		break;
> +	case LTT_TRACE_HYBRID:
> +		ret = lttctl_set_channel_overwrite(name, "cpu", 1);
> +		if (ret)
> +			goto set_overwrite_fail;
> +		break;
> +	default:
> +		fprintf(stderr, "%s: args invalid\n", __func__);
> +		ret = -EINVAL;
> +		goto set_overwrite_fail;
> +	}
> +
> +	ret = lttctl_set_trans(name, trace_type);
> +	if (ret)
> +		goto set_trans_fail;
> +
> +	for (i = 0; i < sizeof(chan_infos) / sizeof(chan_infos[0]); i++) {
> +		switch (chan_infos[i].buf_type) {
> +		case 0:
> +			if (subbuf_size_low) {
> +				ret = lttctl_set_channel_subbuf_size(name,
> +					chan_infos[i].name, subbuf_size_low);
> +				if (ret)
> +					goto set_channelbuf_fail;
> +			}
> +			if (n_subbufs_low) {
> +				ret = lttctl_set_channel_subbuf_num(name,
> +					chan_infos[i].name, n_subbufs_low);
> +				if (ret)
> +					goto set_channelbuf_fail;
> +			}
> +			break;
> +		case 1:
> +			if (subbuf_size_med) {
> +				ret = lttctl_set_channel_subbuf_size(name,
> +					chan_infos[i].name, subbuf_size_med);
> +				if (ret)
> +					goto set_channelbuf_fail;
> +			}
> +			if (n_subbufs_med) {
> +				ret = lttctl_set_channel_subbuf_num(name,
> +					chan_infos[i].name, n_subbufs_med);
> +				if (ret)
> +					goto set_channelbuf_fail;
> +			}
> +			break;
> +		case 2:
> +			if (subbuf_size_high) {
> +				ret = lttctl_set_channel_subbuf_size(name,
> +					chan_infos[i].name, subbuf_size_high);
> +				if (ret)
> +					goto set_channelbuf_fail;
> +			}
> +			if (n_subbufs_high) {
> +				ret = lttctl_set_channel_subbuf_num(name,
> +					chan_infos[i].name, n_subbufs_high);
> +				if (ret)
> +					goto set_channelbuf_fail;
> +			}
> +			break;
> +		default:
> +			fprintf(stderr, "%s: unknown error\n", __func__);
> +			ret = -EINVAL;
> +			goto set_channelbuf_fail;
> +		}
> +	}
> +
> +	ret = lttctl_alloc_trace(name);
> +	if (ret)
> +		goto alloc_trace_fail;
> +
> +	return 0;
> +
> +alloc_trace_fail:
> +set_channelbuf_fail:
> +set_trans_fail:
> +set_overwrite_fail:
> +	lttctl_destroy_trace(name);
> +setup_trace_fail:
> +arg_error:
> +	return ret;
> +}
> diff -Nur ltt-control-0.58-23112008.org/liblttctl/lttctl.h ltt-control-0.58-23112008/liblttctl/lttctl.h
> --- ltt-control-0.58-23112008.org/liblttctl/lttctl.h	2008-11-28 15:08:35.000000000 +0800
> +++ ltt-control-0.58-23112008/liblttctl/lttctl.h	2008-11-28 15:08:35.000000000 +0800
> @@ -14,86 +14,27 @@
>   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	See the
>   * GNU General Public License for more details.
>   *
> - *
> - * Inspired from iptables, by James Morris <jmorris at intercode.com.au>.
> - * 
>   */
>  
>  #ifndef _LIBLTT_H
>  #define _LIBLTT_H
>  
> -#include <linux/limits.h>
> -#include <asm/types.h>
> -#include <sys/socket.h>
> -#include <linux/netlink.h>
> -
> -#ifndef NETLINK_LTT
> -#define NETLINK_LTT 31
> -#endif
> -
> -
> -enum trace_op {
> -	OP_CREATE,
> -	OP_DESTROY,
> -	OP_START,
> -	OP_STOP,
> -	OP_NONE
> -};
> -
>  enum trace_mode {
>  	LTT_TRACE_NORMAL,
>  	LTT_TRACE_FLIGHT,
> -	LTT_TRACE_HYBRID
> +	LTT_TRACE_HYBRID,
>  };
>  
> -typedef struct lttctl_peer_msg {
> -	char trace_name[NAME_MAX];
> -	char trace_type[NAME_MAX];
> -	enum trace_op op;
> -	union {
> -		struct {
> -			enum trace_mode mode;
> -			unsigned subbuf_size_low;
> -			unsigned n_subbufs_low;
> -			unsigned subbuf_size_med;
> -			unsigned n_subbufs_med;
> -			unsigned subbuf_size_high;
> -			unsigned n_subbufs_high;
> -		} new_trace;
> -	} args;
> -} lttctl_peer_msg_t;
> -
> -
> -struct lttctl_handle
> -{
> -	int fd;
> -	//u_int8_t blocking;
> -	struct sockaddr_nl local;
> -	struct sockaddr_nl peer;
> -};
> +int lttctl_init(void);
> +int lttctl_destroy(void);
>  
> -typedef struct lttctl_resp_msg {
> -	int err;
> -} lttctl_resp_msg_t;
> -
> -struct lttctl_handle *lttctl_create_handle(void);
> -
> -int lttctl_destroy_handle(struct lttctl_handle *h);
> -
> -
> -int lttctl_create_trace(const struct lttctl_handle *h,
> -		char *name, enum trace_mode mode, char *trace_type,
> +int lttctl_create_trace(const char *name, enum trace_mode mode,
> +		const char *trace_type,
>  		unsigned subbuf_size_low, unsigned n_subbufs_low,
>  		unsigned subbuf_size_med, unsigned n_subbufs_med,
>  		unsigned subbuf_size_high, unsigned n_subbufs_high);
> +int lttctl_destroy_trace(const char *name);
> +int lttctl_start(const char *name);
> +int lttctl_stop(const char *name);
>  
> -int lttctl_destroy_trace(const struct lttctl_handle *handle, char *name);
> -
> -int lttctl_start(const struct lttctl_handle *handle, char *name);
> -
> -int lttctl_stop(const struct lttctl_handle *handle, char *name);
> -
> -#define LTTCTLM_BASE	0x10
> -#define LTTCTLM_CONTROL	(LTTCTLM_BASE + 1)	/* LTT control message */
> -
> -#endif //_LIBLTT_H
> +#endif /*_LIBLTT_H */
> diff -Nur ltt-control-0.58-23112008.org/lttctl/lttctl.c ltt-control-0.58-23112008/lttctl/lttctl.c
> --- ltt-control-0.58-23112008.org/lttctl/lttctl.c	2008-11-28 15:08:35.000000000 +0800
> +++ ltt-control-0.58-23112008/lttctl/lttctl.c	2008-11-28 15:08:35.000000000 +0800
> @@ -16,14 +16,10 @@
>  #include <errno.h>
>  #include <stdio.h>
>  #include <stdlib.h>
> -#include <sys/types.h>
>  #include <sys/wait.h>
>  #include <unistd.h>
> -#include <signal.h>
> -#include <dirent.h>
>  #include <string.h>
>  #include <limits.h>
> -#include <sys/stat.h>
>  
>  /* Buffer for file copy : 4k seems optimal. */
>  #define BUF_SIZE 4096
> @@ -40,9 +36,9 @@
>  	CTL_OP_NONE
>  };
>  
> -static char *trace_name = NULL;
> -static char *trace_type = "relay";
> -static char *mode_name = NULL;
> +static const char *trace_name = NULL;
> +static const char *trace_type = "relay";
> +static const char *mode_name = NULL;
>  static unsigned subbuf_size_low = 0;
>  static unsigned n_subbufs_low = 0;
>  static unsigned subbuf_size_med = 0;
> @@ -52,10 +48,10 @@
>  static unsigned append_trace = 0;
>  static enum trace_mode mode = LTT_TRACE_NORMAL;
>  static enum trace_ctl_op op = CTL_OP_NONE;
> -static char *channel_root = NULL;
> +static const char *channel_root = NULL;
>  static char channel_root_default[PATH_MAX];
> -static char *trace_root = NULL;
> -static char *num_threads = "1";
> +static const char *trace_root = NULL;
> +static const char *num_threads = "1";
>  
>  /* Args :
>   *
> @@ -352,22 +348,22 @@
>  	}
>  }
>  
> -int lttctl_daemon(struct lttctl_handle *handle, char *trace_name)
> +int lttctl_daemon(const char *trace_name)
>  {
>  	char channel_path[PATH_MAX] = "";
>  	pid_t pid;
>  	int ret;
> -	char *lttd_path = getenv("LTT_DAEMON");
> +	const char *lttd_path = getenv("LTT_DAEMON");
>  
> -	if(lttd_path == NULL) lttd_path = 
> -		PACKAGE_BIN_DIR "/lttd";
> +	if(lttd_path == NULL)
> +		lttd_path = PACKAGE_BIN_DIR "/lttd";
>  	
>  	strcat(channel_path, channel_root);
>  	strcat(channel_path, "/");
>  	strcat(channel_path, trace_name);
>  
>  	
> -	ret = lttctl_create_trace(handle, trace_name, mode, trace_type,
> +	ret = lttctl_create_trace(trace_name, mode, trace_type,
>  		subbuf_size_low, n_subbufs_low,
>  		subbuf_size_med, n_subbufs_med,
>  		subbuf_size_high, n_subbufs_high);
> @@ -419,7 +415,7 @@
>  		perror("Error in forking for lttd daemon");
>  	}
>  
> -	ret = lttctl_start(handle, trace_name);
> +	ret = lttctl_start(trace_name);
>  	if(ret != 0) goto start_error;
>  
>  	return 0;
> @@ -427,7 +423,7 @@
>  	/* error handling */
>  start_error:
>  	printf("Trace start error\n");
> -	ret |= lttctl_destroy_trace(handle, trace_name);
> +	ret |= lttctl_destroy_trace(trace_name);
>  create_error:
>  	return ret;
>  }
> @@ -435,22 +431,22 @@
>  
>  
>  
> -int lttctl_daemon_hybrid_finish(struct lttctl_handle *handle, char *trace_name)
> +int lttctl_daemon_hybrid_finish(const char *trace_name)
>  {
>  	char channel_path[PATH_MAX] = "";
>  	pid_t pid;
>  	int ret;
> -	char *lttd_path = getenv("LTT_DAEMON");
> +	const char *lttd_path = getenv("LTT_DAEMON");
>  
> -	if(lttd_path == NULL) lttd_path = 
> -		PACKAGE_BIN_DIR "/lttd";
> +	if(lttd_path == NULL)
> +		lttd_path = PACKAGE_BIN_DIR "/lttd";
>  	
>  	strcat(channel_path, channel_root);
>  	strcat(channel_path, "/");
>  	strcat(channel_path, trace_name);
>  
>  	
> -	ret = lttctl_stop(handle, trace_name);
> +	ret = lttctl_stop(trace_name);
>  	if(ret != 0) goto stop_error;
>  
>  	pid = fork();
> @@ -490,7 +486,7 @@
>  		perror("Error in forking for lttd daemon");
>  	}
>  
> -	ret = lttctl_destroy_trace(handle, trace_name);
> +	ret = lttctl_destroy_trace(trace_name);
>  	if(ret != 0) goto destroy_error;
>  
>  	return 0;
> @@ -507,8 +503,7 @@
>  int main(int argc, char ** argv)
>  {
>  	int ret;
> -	struct lttctl_handle *handle;
> -	
> +
>  	ret = parse_arguments(argc, argv);
>  
>  	if(ret != 0) show_arguments();
> @@ -516,51 +511,51 @@
>  	if(ret == -1) return 0;
>  
>  	show_info();
> -	
> -	handle = lttctl_create_handle();
> -	
> -	if(handle == NULL) return -1;
> +
> +	ret = lttctl_init();
> +	if (ret != 0)
> +		return ret;
>  	
>  	switch(op) {
>  		case CTL_OP_CREATE_START:
> -			ret = lttctl_create_trace(handle, trace_name, mode, trace_type,
> +			ret = lttctl_create_trace(trace_name, mode, trace_type,
>  			subbuf_size_low, n_subbufs_low,
>  			subbuf_size_med, n_subbufs_med,
>  			subbuf_size_high, n_subbufs_high);
>  			if(!ret)
> -				ret = lttctl_start(handle, trace_name);
> +				ret = lttctl_start(trace_name);
>  			break;
>  		case CTL_OP_CREATE:
> -			ret = lttctl_create_trace(handle, trace_name, mode, trace_type,
> +			ret = lttctl_create_trace(trace_name, mode, trace_type,
>  			subbuf_size_low, n_subbufs_low,
>  			subbuf_size_med, n_subbufs_med,
>  			subbuf_size_high, n_subbufs_high);
>  			break;
>  		case CTL_OP_DESTROY:
> -			ret = lttctl_destroy_trace(handle, trace_name);
> +			ret = lttctl_destroy_trace(trace_name);
>  			break;
>  		case CTL_OP_STOP_DESTROY:
> -			ret = lttctl_stop(handle, trace_name);
> +			ret = lttctl_stop(trace_name);
>  			if(!ret)
> -				ret = lttctl_destroy_trace(handle, trace_name);
> +				ret = lttctl_destroy_trace(trace_name);
>  			break;
>  		case CTL_OP_START:
> -			ret = lttctl_start(handle, trace_name);
> +			ret = lttctl_start(trace_name);
>  			break;
>  		case CTL_OP_STOP:
> -			ret = lttctl_stop(handle, trace_name);
> +			ret = lttctl_stop(trace_name);
>  			break;
>  		case CTL_OP_DAEMON:
> -			ret = lttctl_daemon(handle, trace_name);
> +			ret = lttctl_daemon(trace_name);
>  			break;
>  		case CTL_OP_DAEMON_HYBRID_FINISH:
> -			ret = lttctl_daemon_hybrid_finish(handle, trace_name);
> +			ret = lttctl_daemon_hybrid_finish(trace_name);
>  			break;
>  		case CTL_OP_NONE:
>  			break;
>  	}
>  
> -	ret |= lttctl_destroy_handle(handle);
> -	
> +	lttctl_destroy();
> +
>  	return ret;
>  }
> 
> _______________________________________________
> ltt-dev mailing list
> ltt-dev at lists.casi.polymtl.ca
> http://lists.casi.polymtl.ca/cgi-bin/mailman/listinfo/ltt-dev
> 

-- 
Mathieu Desnoyers
OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F  BA06 3F25 A8FE 3BAE 9A68




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