tools: Add guest trace agent as a user tool
This patch adds a user tool, "trace agent" for sending trace data of a guest to a Host in low overhead. This agent has the following functions: - splice a page of ring-buffer to read_pipe without memory copying - splice the page from write_pipe to virtio-console without memory copying - write trace data to stdout by using -o option - controlled by start/stop orders from a Host Changes in v2: - Cleanup (change fprintf() to pr_err() and an include guard) Signed-off-by: Yoshihiro YUNOMAE <yoshihiro.yunomae.ez@hitachi.com> Acked-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This commit is contained in:
Yoshihiro YUNOMAE
Rusty Russell
parent
8ca84a50e5
commit
108fc82596
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@ -0,0 +1,14 @@
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CC = gcc
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CFLAGS = -O2 -Wall
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LFLAG = -lpthread
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all: trace-agent
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.c.o:
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$(CC) $(CFLAGS) $(LFLAG) -c $^ -o $@
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trace-agent: trace-agent.o trace-agent-ctl.o trace-agent-rw.o
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$(CC) $(CFLAGS) $(LFLAG) -o $@ $^
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clean:
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rm -f *.o trace-agent
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@ -0,0 +1,118 @@
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Trace Agent for virtio-trace
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============================
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Trace agent is a user tool for sending trace data of a guest to a Host in low
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overhead. Trace agent has the following functions:
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- splice a page of ring-buffer to read_pipe without memory copying
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- splice the page from write_pipe to virtio-console without memory copying
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- write trace data to stdout by using -o option
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- controlled by start/stop orders from a Host
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The trace agent operates as follows:
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1) Initialize all structures.
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2) Create a read/write thread per CPU. Each thread is bound to a CPU.
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The read/write threads hold it.
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3) A controller thread does poll() for a start order of a host.
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4) After the controller of the trace agent receives a start order from a host,
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the controller wake read/write threads.
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5) The read/write threads start to read trace data from ring-buffers and
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write the data to virtio-serial.
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6) If the controller receives a stop order from a host, the read/write threads
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stop to read trace data.
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Files
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=====
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README: this file
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Makefile: Makefile of trace agent for virtio-trace
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trace-agent.c: includes main function, sets up for operating trace agent
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trace-agent.h: includes all structures and some macros
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trace-agent-ctl.c: includes controller function for read/write threads
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trace-agent-rw.c: includes read/write threads function
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Setup
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=====
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To use this trace agent for virtio-trace, we need to prepare some virtio-serial
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I/Fs.
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1) Make FIFO in a host
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virtio-trace uses virtio-serial pipe as trace data paths as to the number
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of CPUs and a control path, so FIFO (named pipe) should be created as follows:
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# mkdir /tmp/virtio-trace/
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# mkfifo /tmp/virtio-trace/trace-path-cpu{0,1,2,...,X}.{in,out}
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# mkfifo /tmp/virtio-trace/agent-ctl-path.{in,out}
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For example, if a guest use three CPUs, the names are
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trace-path-cpu{0,1,2}.{in.out}
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and
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agent-ctl-path.{in,out}.
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2) Set up of virtio-serial pipe in a host
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Add qemu option to use virtio-serial pipe.
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##virtio-serial device##
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-device virtio-serial-pci,id=virtio-serial0\
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##control path##
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-chardev pipe,id=charchannel0,path=/tmp/virtio-trace/agent-ctl-path\
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-device virtserialport,bus=virtio-serial0.0,nr=1,chardev=charchannel0,\
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id=channel0,name=agent-ctl-path\
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##data path##
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-chardev pipe,id=charchannel1,path=/tmp/virtio-trace/trace-path-cpu0\
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-device virtserialport,bus=virtio-serial0.0,nr=2,chardev=charchannel0,\
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id=channel1,name=trace-path-cpu0\
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...
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If you manage guests with libvirt, add the following tags to domain XML files.
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Then, libvirt passes the same command option to qemu.
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<channel type='pipe'>
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<source path='/tmp/virtio-trace/agent-ctl-path'/>
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<target type='virtio' name='agent-ctl-path'/>
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<address type='virtio-serial' controller='0' bus='0' port='0'/>
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</channel>
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<channel type='pipe'>
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<source path='/tmp/virtio-trace/trace-path-cpu0'/>
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<target type='virtio' name='trace-path-cpu0'/>
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<address type='virtio-serial' controller='0' bus='0' port='1'/>
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</channel>
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...
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Here, chardev names are restricted to trace-path-cpuX and agent-ctl-path. For
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example, if a guest use three CPUs, chardev names should be trace-path-cpu0,
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trace-path-cpu1, trace-path-cpu2, and agent-ctl-path.
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3) Boot the guest
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You can find some chardev in /dev/virtio-ports/ in the guest.
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Run
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===
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0) Build trace agent in a guest
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$ make
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1) Enable ftrace in the guest
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<Example>
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# echo 1 > /sys/kernel/debug/tracing/events/sched/enable
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2) Run trace agent in the guest
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This agent must be operated as root.
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# ./trace-agent
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read/write threads in the agent wait for start order from host. If you add -o
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option, trace data are output via stdout in the guest.
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3) Open FIFO in a host
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# cat /tmp/virtio-trace/trace-path-cpu0.out
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If a host does not open these, trace data get stuck in buffers of virtio. Then,
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the guest will stop by specification of chardev in QEMU. This blocking mode may
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be solved in the future.
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4) Start to read trace data by ordering from a host
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A host injects read start order to the guest via virtio-serial.
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# echo 1 > /tmp/virtio-trace/agent-ctl-path.in
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5) Stop to read trace data by ordering from a host
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A host injects read stop order to the guest via virtio-serial.
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# echo 0 > /tmp/virtio-trace/agent-ctl-path.in
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@ -0,0 +1,137 @@
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/*
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* Controller of read/write threads for virtio-trace
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*
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* Copyright (C) 2012 Hitachi, Ltd.
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* Created by Yoshihiro Yunomae <yoshihiro.yunomae.ez@hitachi.com>
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* Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
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*
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* Licensed under GPL version 2 only.
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*
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*/
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#define _GNU_SOURCE
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#include <fcntl.h>
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#include <poll.h>
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#include <signal.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <unistd.h>
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#include "trace-agent.h"
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#define HOST_MSG_SIZE 256
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#define EVENT_WAIT_MSEC 100
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static volatile sig_atomic_t global_signal_val;
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bool global_sig_receive; /* default false */
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bool global_run_operation; /* default false*/
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/* Handle SIGTERM/SIGINT/SIGQUIT to exit */
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static void signal_handler(int sig)
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{
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global_signal_val = sig;
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}
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int rw_ctl_init(const char *ctl_path)
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{
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int ctl_fd;
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ctl_fd = open(ctl_path, O_RDONLY);
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if (ctl_fd == -1) {
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pr_err("Cannot open ctl_fd\n");
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goto error;
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}
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return ctl_fd;
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error:
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exit(EXIT_FAILURE);
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}
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static int wait_order(int ctl_fd)
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{
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struct pollfd poll_fd;
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int ret = 0;
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while (!global_sig_receive) {
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poll_fd.fd = ctl_fd;
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poll_fd.events = POLLIN;
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ret = poll(&poll_fd, 1, EVENT_WAIT_MSEC);
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if (global_signal_val) {
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global_sig_receive = true;
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pr_info("Receive interrupt %d\n", global_signal_val);
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/* Wakes rw-threads when they are sleeping */
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if (!global_run_operation)
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pthread_cond_broadcast(&cond_wakeup);
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ret = -1;
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break;
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}
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if (ret < 0) {
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pr_err("Polling error\n");
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goto error;
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}
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if (ret)
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break;
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};
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return ret;
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error:
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exit(EXIT_FAILURE);
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}
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/*
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* contol read/write threads by handling global_run_operation
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*/
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void *rw_ctl_loop(int ctl_fd)
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{
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ssize_t rlen;
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char buf[HOST_MSG_SIZE];
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int ret;
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/* Setup signal handlers */
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signal(SIGTERM, signal_handler);
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signal(SIGINT, signal_handler);
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signal(SIGQUIT, signal_handler);
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while (!global_sig_receive) {
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ret = wait_order(ctl_fd);
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if (ret < 0)
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break;
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rlen = read(ctl_fd, buf, sizeof(buf));
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if (rlen < 0) {
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pr_err("read data error in ctl thread\n");
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goto error;
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}
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if (rlen == 2 && buf[0] == '1') {
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/*
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* If host writes '1' to a control path,
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* this controller wakes all read/write threads.
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*/
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global_run_operation = true;
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pthread_cond_broadcast(&cond_wakeup);
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pr_debug("Wake up all read/write threads\n");
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} else if (rlen == 2 && buf[0] == '0') {
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/*
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* If host writes '0' to a control path, read/write
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* threads will wait for notification from Host.
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*/
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global_run_operation = false;
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pr_debug("Stop all read/write threads\n");
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} else
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pr_info("Invalid host notification: %s\n", buf);
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}
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return NULL;
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error:
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exit(EXIT_FAILURE);
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}
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@ -0,0 +1,192 @@
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/*
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* Read/write thread of a guest agent for virtio-trace
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*
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* Copyright (C) 2012 Hitachi, Ltd.
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* Created by Yoshihiro Yunomae <yoshihiro.yunomae.ez@hitachi.com>
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* Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
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*
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* Licensed under GPL version 2 only.
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*
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*/
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#define _GNU_SOURCE
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#include <fcntl.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <unistd.h>
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#include <sys/syscall.h>
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#include "trace-agent.h"
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#define READ_WAIT_USEC 100000
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void *rw_thread_info_new(void)
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{
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struct rw_thread_info *rw_ti;
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rw_ti = zalloc(sizeof(struct rw_thread_info));
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if (rw_ti == NULL) {
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pr_err("rw_thread_info zalloc error\n");
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exit(EXIT_FAILURE);
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}
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rw_ti->cpu_num = -1;
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rw_ti->in_fd = -1;
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rw_ti->out_fd = -1;
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rw_ti->read_pipe = -1;
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rw_ti->write_pipe = -1;
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rw_ti->pipe_size = PIPE_INIT;
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return rw_ti;
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}
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void *rw_thread_init(int cpu, const char *in_path, const char *out_path,
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bool stdout_flag, unsigned long pipe_size,
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struct rw_thread_info *rw_ti)
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{
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int data_pipe[2];
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rw_ti->cpu_num = cpu;
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/* set read(input) fd */
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rw_ti->in_fd = open(in_path, O_RDONLY);
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if (rw_ti->in_fd == -1) {
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pr_err("Could not open in_fd (CPU:%d)\n", cpu);
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goto error;
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}
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/* set write(output) fd */
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if (!stdout_flag) {
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/* virtio-serial output mode */
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rw_ti->out_fd = open(out_path, O_WRONLY);
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if (rw_ti->out_fd == -1) {
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pr_err("Could not open out_fd (CPU:%d)\n", cpu);
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goto error;
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}
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} else
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/* stdout mode */
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rw_ti->out_fd = STDOUT_FILENO;
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if (pipe2(data_pipe, O_NONBLOCK) < 0) {
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pr_err("Could not create pipe in rw-thread(%d)\n", cpu);
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goto error;
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}
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/*
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* Size of pipe is 64kB in default based on fs/pipe.c.
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* To read/write trace data speedy, pipe size is changed.
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*/
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if (fcntl(*data_pipe, F_SETPIPE_SZ, pipe_size) < 0) {
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pr_err("Could not change pipe size in rw-thread(%d)\n", cpu);
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goto error;
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}
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rw_ti->read_pipe = data_pipe[1];
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rw_ti->write_pipe = data_pipe[0];
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rw_ti->pipe_size = pipe_size;
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return NULL;
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error:
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exit(EXIT_FAILURE);
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}
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/* Bind a thread to a cpu */
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static void bind_cpu(int cpu_num)
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{
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cpu_set_t mask;
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CPU_ZERO(&mask);
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CPU_SET(cpu_num, &mask);
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/* bind my thread to cpu_num by assigning zero to the first argument */
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if (sched_setaffinity(0, sizeof(mask), &mask) == -1)
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pr_err("Could not set CPU#%d affinity\n", (int)cpu_num);
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}
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static void *rw_thread_main(void *thread_info)
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{
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ssize_t rlen, wlen;
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ssize_t ret;
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struct rw_thread_info *ts = (struct rw_thread_info *)thread_info;
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bind_cpu(ts->cpu_num);
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while (1) {
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/* Wait for a read order of trace data by Host OS */
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if (!global_run_operation) {
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pthread_mutex_lock(&mutex_notify);
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pthread_cond_wait(&cond_wakeup, &mutex_notify);
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pthread_mutex_unlock(&mutex_notify);
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}
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if (global_sig_receive)
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break;
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/*
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* Each thread read trace_pipe_raw of each cpu bounding the
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* thread, so contention of multi-threads does not occur.
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*/
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rlen = splice(ts->in_fd, NULL, ts->read_pipe, NULL,
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ts->pipe_size, SPLICE_F_MOVE | SPLICE_F_MORE);
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if (rlen < 0) {
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pr_err("Splice_read in rw-thread(%d)\n", ts->cpu_num);
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goto error;
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} else if (rlen == 0) {
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/*
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* If trace data do not exist or are unreadable not
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* for exceeding the page size, splice_read returns
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* NULL. Then, this waits for being filled the data in a
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* ring-buffer.
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*/
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usleep(READ_WAIT_USEC);
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pr_debug("Read retry(cpu:%d)\n", ts->cpu_num);
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continue;
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}
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wlen = 0;
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do {
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ret = splice(ts->write_pipe, NULL, ts->out_fd, NULL,
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rlen - wlen,
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SPLICE_F_MOVE | SPLICE_F_MORE);
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if (ret < 0) {
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pr_err("Splice_write in rw-thread(%d)\n",
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ts->cpu_num);
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goto error;
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} else if (ret == 0)
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/*
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* When host reader is not in time for reading
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* trace data, guest will be stopped. This is
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* because char dev in QEMU is not supported
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* non-blocking mode. Then, writer might be
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* sleep in that case.
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* This sleep will be removed by supporting
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* non-blocking mode.
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*/
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sleep(1);
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wlen += ret;
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} while (wlen < rlen);
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}
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return NULL;
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error:
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exit(EXIT_FAILURE);
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}
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pthread_t rw_thread_run(struct rw_thread_info *rw_ti)
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{
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int ret;
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pthread_t rw_thread_per_cpu;
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ret = pthread_create(&rw_thread_per_cpu, NULL, rw_thread_main, rw_ti);
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if (ret != 0) {
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pr_err("Could not create a rw thread(%d)\n", rw_ti->cpu_num);
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exit(EXIT_FAILURE);
|
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}
|
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return rw_thread_per_cpu;
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}
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|
|
@ -0,0 +1,270 @@
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/*
|
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* Guest agent for virtio-trace
|
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*
|
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* Copyright (C) 2012 Hitachi, Ltd.
|
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* Created by Yoshihiro Yunomae <yoshihiro.yunomae.ez@hitachi.com>
|
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* Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
|
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*
|
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* Licensed under GPL version 2 only.
|
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*
|
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*/
|
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|
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#define _GNU_SOURCE
|
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#include <limits.h>
|
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#include <stdio.h>
|
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#include <stdlib.h>
|
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#include <unistd.h>
|
||||
#include "trace-agent.h"
|
||||
|
||||
#define PAGE_SIZE (sysconf(_SC_PAGE_SIZE))
|
||||
#define PIPE_DEF_BUFS 16
|
||||
#define PIPE_MIN_SIZE (PAGE_SIZE*PIPE_DEF_BUFS)
|
||||
#define PIPE_MAX_SIZE (1024*1024)
|
||||
#define READ_PATH_FMT \
|
||||
"/sys/kernel/debug/tracing/per_cpu/cpu%d/trace_pipe_raw"
|
||||
#define WRITE_PATH_FMT "/dev/virtio-ports/trace-path-cpu%d"
|
||||
#define CTL_PATH "/dev/virtio-ports/agent-ctl-path"
|
||||
|
||||
pthread_mutex_t mutex_notify = PTHREAD_MUTEX_INITIALIZER;
|
||||
pthread_cond_t cond_wakeup = PTHREAD_COND_INITIALIZER;
|
||||
|
||||
static int get_total_cpus(void)
|
||||
{
|
||||
int nr_cpus = (int)sysconf(_SC_NPROCESSORS_CONF);
|
||||
|
||||
if (nr_cpus <= 0) {
|
||||
pr_err("Could not read cpus\n");
|
||||
goto error;
|
||||
} else if (nr_cpus > MAX_CPUS) {
|
||||
pr_err("Exceed max cpus(%d)\n", (int)MAX_CPUS);
|
||||
goto error;
|
||||
}
|
||||
|
||||
return nr_cpus;
|
||||
|
||||
error:
|
||||
exit(EXIT_FAILURE);
|
||||
}
|
||||
|
||||
static void *agent_info_new(void)
|
||||
{
|
||||
struct agent_info *s;
|
||||
int i;
|
||||
|
||||
s = zalloc(sizeof(struct agent_info));
|
||||
if (s == NULL) {
|
||||
pr_err("agent_info zalloc error\n");
|
||||
exit(EXIT_FAILURE);
|
||||
}
|
||||
|
||||
s->pipe_size = PIPE_INIT;
|
||||
s->use_stdout = false;
|
||||
s->cpus = get_total_cpus();
|
||||
s->ctl_fd = -1;
|
||||
|
||||
/* read/write threads init */
|
||||
for (i = 0; i < s->cpus; i++)
|
||||
s->rw_ti[i] = rw_thread_info_new();
|
||||
|
||||
return s;
|
||||
}
|
||||
|
||||
static unsigned long parse_size(const char *arg)
|
||||
{
|
||||
unsigned long value, round;
|
||||
char *ptr;
|
||||
|
||||
value = strtoul(arg, &ptr, 10);
|
||||
switch (*ptr) {
|
||||
case 'K': case 'k':
|
||||
value <<= 10;
|
||||
break;
|
||||
case 'M': case 'm':
|
||||
value <<= 20;
|
||||
break;
|
||||
default:
|
||||
break;
|
||||
}
|
||||
|
||||
if (value > PIPE_MAX_SIZE) {
|
||||
pr_err("Pipe size must be less than 1MB\n");
|
||||
goto error;
|
||||
} else if (value < PIPE_MIN_SIZE) {
|
||||
pr_err("Pipe size must be over 64KB\n");
|
||||
goto error;
|
||||
}
|
||||
|
||||
/* Align buffer size with page unit */
|
||||
round = value & (PAGE_SIZE - 1);
|
||||
value = value - round;
|
||||
|
||||
return value;
|
||||
error:
|
||||
return 0;
|
||||
}
|
||||
|
||||
static void usage(char const *prg)
|
||||
{
|
||||
pr_err("usage: %s [-h] [-o] [-s <size of pipe>]\n", prg);
|
||||
}
|
||||
|
||||
static const char *make_path(int cpu_num, bool this_is_write_path)
|
||||
{
|
||||
int ret;
|
||||
char *buf;
|
||||
|
||||
buf = zalloc(PATH_MAX);
|
||||
if (buf == NULL) {
|
||||
pr_err("Could not allocate buffer\n");
|
||||
goto error;
|
||||
}
|
||||
|
||||
if (this_is_write_path)
|
||||
/* write(output) path */
|
||||
ret = snprintf(buf, PATH_MAX, WRITE_PATH_FMT, cpu_num);
|
||||
else
|
||||
/* read(input) path */
|
||||
ret = snprintf(buf, PATH_MAX, READ_PATH_FMT, cpu_num);
|
||||
|
||||
if (ret <= 0) {
|
||||
pr_err("Failed to generate %s path(CPU#%d):%d\n",
|
||||
this_is_write_path ? "read" : "write", cpu_num, ret);
|
||||
goto error;
|
||||
}
|
||||
|
||||
return buf;
|
||||
|
||||
error:
|
||||
free(buf);
|
||||
return NULL;
|
||||
}
|
||||
|
||||
static const char *make_input_path(int cpu_num)
|
||||
{
|
||||
return make_path(cpu_num, false);
|
||||
}
|
||||
|
||||
static const char *make_output_path(int cpu_num)
|
||||
{
|
||||
return make_path(cpu_num, true);
|
||||
}
|
||||
|
||||
static void *agent_info_init(struct agent_info *s)
|
||||
{
|
||||
int cpu;
|
||||
const char *in_path = NULL;
|
||||
const char *out_path = NULL;
|
||||
|
||||
/* init read/write threads */
|
||||
for (cpu = 0; cpu < s->cpus; cpu++) {
|
||||
/* set read(input) path per read/write thread */
|
||||
in_path = make_input_path(cpu);
|
||||
if (in_path == NULL)
|
||||
goto error;
|
||||
|
||||
/* set write(output) path per read/write thread*/
|
||||
if (!s->use_stdout) {
|
||||
out_path = make_output_path(cpu);
|
||||
if (out_path == NULL)
|
||||
goto error;
|
||||
} else
|
||||
/* stdout mode */
|
||||
pr_debug("stdout mode\n");
|
||||
|
||||
rw_thread_init(cpu, in_path, out_path, s->use_stdout,
|
||||
s->pipe_size, s->rw_ti[cpu]);
|
||||
}
|
||||
|
||||
/* init controller of read/write threads */
|
||||
s->ctl_fd = rw_ctl_init((const char *)CTL_PATH);
|
||||
|
||||
return NULL;
|
||||
|
||||
error:
|
||||
exit(EXIT_FAILURE);
|
||||
}
|
||||
|
||||
static void *parse_args(int argc, char *argv[], struct agent_info *s)
|
||||
{
|
||||
int cmd;
|
||||
unsigned long size;
|
||||
|
||||
while ((cmd = getopt(argc, argv, "hos:")) != -1) {
|
||||
switch (cmd) {
|
||||
/* stdout mode */
|
||||
case 'o':
|
||||
s->use_stdout = true;
|
||||
break;
|
||||
/* size of pipe */
|
||||
case 's':
|
||||
size = parse_size(optarg);
|
||||
if (size == 0)
|
||||
goto error;
|
||||
s->pipe_size = size;
|
||||
break;
|
||||
case 'h':
|
||||
default:
|
||||
usage(argv[0]);
|
||||
goto error;
|
||||
}
|
||||
}
|
||||
|
||||
agent_info_init(s);
|
||||
|
||||
return NULL;
|
||||
|
||||
error:
|
||||
exit(EXIT_FAILURE);
|
||||
}
|
||||
|
||||
static void agent_main_loop(struct agent_info *s)
|
||||
{
|
||||
int cpu;
|
||||
pthread_t rw_thread_per_cpu[MAX_CPUS];
|
||||
|
||||
/* Start all read/write threads */
|
||||
for (cpu = 0; cpu < s->cpus; cpu++)
|
||||
rw_thread_per_cpu[cpu] = rw_thread_run(s->rw_ti[cpu]);
|
||||
|
||||
rw_ctl_loop(s->ctl_fd);
|
||||
|
||||
/* Finish all read/write threads */
|
||||
for (cpu = 0; cpu < s->cpus; cpu++) {
|
||||
int ret;
|
||||
|
||||
ret = pthread_join(rw_thread_per_cpu[cpu], NULL);
|
||||
if (ret != 0) {
|
||||
pr_err("pthread_join() error:%d (cpu %d)\n", ret, cpu);
|
||||
exit(EXIT_FAILURE);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
static void agent_info_free(struct agent_info *s)
|
||||
{
|
||||
int i;
|
||||
|
||||
close(s->ctl_fd);
|
||||
for (i = 0; i < s->cpus; i++) {
|
||||
close(s->rw_ti[i]->in_fd);
|
||||
close(s->rw_ti[i]->out_fd);
|
||||
close(s->rw_ti[i]->read_pipe);
|
||||
close(s->rw_ti[i]->write_pipe);
|
||||
free(s->rw_ti[i]);
|
||||
}
|
||||
free(s);
|
||||
}
|
||||
|
||||
int main(int argc, char *argv[])
|
||||
{
|
||||
struct agent_info *s = NULL;
|
||||
|
||||
s = agent_info_new();
|
||||
parse_args(argc, argv, s);
|
||||
|
||||
agent_main_loop(s);
|
||||
|
||||
agent_info_free(s);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
|
@ -0,0 +1,75 @@
|
|||
#ifndef __TRACE_AGENT_H__
|
||||
#define __TRACE_AGENT_H__
|
||||
#include <pthread.h>
|
||||
#include <stdbool.h>
|
||||
|
||||
#define MAX_CPUS 256
|
||||
#define PIPE_INIT (1024*1024)
|
||||
|
||||
/*
|
||||
* agent_info - structure managing total information of guest agent
|
||||
* @pipe_size: size of pipe (default 1MB)
|
||||
* @use_stdout: set to true when o option is added (default false)
|
||||
* @cpus: total number of CPUs
|
||||
* @ctl_fd: fd of control path, /dev/virtio-ports/agent-ctl-path
|
||||
* @rw_ti: structure managing information of read/write threads
|
||||
*/
|
||||
struct agent_info {
|
||||
unsigned long pipe_size;
|
||||
bool use_stdout;
|
||||
int cpus;
|
||||
int ctl_fd;
|
||||
struct rw_thread_info *rw_ti[MAX_CPUS];
|
||||
};
|
||||
|
||||
/*
|
||||
* rw_thread_info - structure managing a read/write thread a cpu
|
||||
* @cpu_num: cpu number operating this read/write thread
|
||||
* @in_fd: fd of reading trace data path in cpu_num
|
||||
* @out_fd: fd of writing trace data path in cpu_num
|
||||
* @read_pipe: fd of read pipe
|
||||
* @write_pipe: fd of write pipe
|
||||
* @pipe_size: size of pipe (default 1MB)
|
||||
*/
|
||||
struct rw_thread_info {
|
||||
int cpu_num;
|
||||
int in_fd;
|
||||
int out_fd;
|
||||
int read_pipe;
|
||||
int write_pipe;
|
||||
unsigned long pipe_size;
|
||||
};
|
||||
|
||||
/* use for stopping rw threads */
|
||||
extern bool global_sig_receive;
|
||||
|
||||
/* use for notification */
|
||||
extern bool global_run_operation;
|
||||
extern pthread_mutex_t mutex_notify;
|
||||
extern pthread_cond_t cond_wakeup;
|
||||
|
||||
/* for controller of read/write threads */
|
||||
extern int rw_ctl_init(const char *ctl_path);
|
||||
extern void *rw_ctl_loop(int ctl_fd);
|
||||
|
||||
/* for trace read/write thread */
|
||||
extern void *rw_thread_info_new(void);
|
||||
extern void *rw_thread_init(int cpu, const char *in_path, const char *out_path,
|
||||
bool stdout_flag, unsigned long pipe_size,
|
||||
struct rw_thread_info *rw_ti);
|
||||
extern pthread_t rw_thread_run(struct rw_thread_info *rw_ti);
|
||||
|
||||
static inline void *zalloc(size_t size)
|
||||
{
|
||||
return calloc(1, size);
|
||||
}
|
||||
|
||||
#define pr_err(format, ...) fprintf(stderr, format, ## __VA_ARGS__)
|
||||
#define pr_info(format, ...) fprintf(stdout, format, ## __VA_ARGS__)
|
||||
#ifdef DEBUG
|
||||
#define pr_debug(format, ...) fprintf(stderr, format, ## __VA_ARGS__)
|
||||
#else
|
||||
#define pr_debug(format, ...) do {} while (0)
|
||||
#endif
|
||||
|
||||
#endif /*__TRACE_AGENT_H__*/
|
||||
Loading…
Reference in New Issue