/*
 * Guest agent for virtio-trace
 *
 * Copyright (C) 2012 Hitachi, Ltd.
 * Created by Yoshihiro Yunomae <yoshihiro.yunomae.ez@hitachi.com>
 *            Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
 *
 * Licensed under GPL version 2 only.
 *
 */

#define _GNU_SOURCE
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#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;
}
00</td></tr>
<tr><th>committer</th><td>Linus Torvalds &lt;torvalds@linux-foundation.org&gt;</td><td class='right'>2017-02-01 11:52:27 -0800</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/drivers/usb/host/xhci-trace.h?h=nds-private-remove&amp;id=6d04dfc8966019b8b0977b2cb942351f13d2b178'>6d04dfc8966019b8b0977b2cb942351f13d2b178</a> (<a href='/cgit.cgi/linux/net-next.git/patch/drivers/usb/host/xhci-trace.h?id=6d04dfc8966019b8b0977b2cb942351f13d2b178'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?h=nds-private-remove&amp;id=6d04dfc8966019b8b0977b2cb942351f13d2b178'>2d4f239c1daff620704b77a992c1e70ce1ce6b08</a> /<a href='/cgit.cgi/linux/net-next.git/tree/drivers/usb/host/xhci-trace.h?h=nds-private-remove&amp;id=6d04dfc8966019b8b0977b2cb942351f13d2b178'>drivers/usb/host/xhci-trace.h</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/drivers/usb/host/xhci-trace.h?h=nds-private-remove&amp;id=2883aaea363f7a897ff06d2e6c73ae7aae285bcb'>2883aaea363f7a897ff06d2e6c73ae7aae285bcb</a> (<a href='/cgit.cgi/linux/net-next.git/diff/drivers/usb/host/xhci-trace.h?h=nds-private-remove&amp;id=6d04dfc8966019b8b0977b2cb942351f13d2b178&amp;id2=2883aaea363f7a897ff06d2e6c73ae7aae285bcb'>diff</a>)</td></tr><tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/drivers/usb/host/xhci-trace.h?h=nds-private-remove&amp;id=06425c308b92eaf60767bc71d359f4cbc7a561f8'>06425c308b92eaf60767bc71d359f4cbc7a561f8</a> (<a href='/cgit.cgi/linux/net-next.git/diff/drivers/usb/host/xhci-trace.h?h=nds-private-remove&amp;id=6d04dfc8966019b8b0977b2cb942351f13d2b178&amp;id2=06425c308b92eaf60767bc71d359f4cbc7a561f8'>diff</a>)</td></tr></table>
<div class='commit-subject'>Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net</div><div class='commit-msg'>Pull networking fixes from David Miller:

 1) Fix handling of interrupt status in stmmac driver. Just because we
    have masked the event from generating interrupts, doesn't mean the
    bit won't still be set in the interrupt status register. From Alexey
    Brodkin.

 2) Fix DMA API debugging splats in gianfar driver, from Arseny Solokha.

 3) Fix off-by-one error in __ip6_append_data(), from Vlad Yasevich.

 4) cls_flow does not match on icmpv6 codes properly, from Simon Horman.

 5) Initial MAC address can be set incorrectly in some scenerios, from
    Ivan Vecera.

 6) Packet header pointer arithmetic fix in ip6_tnl_parse_tlv_end_lim(),
    from Dan Carpenter.

 7) Fix divide by zero in __tcp_select_window(), from Eric Dumazet.

 8) Fix crash in iwlwifi when unregistering thermal zone, from Jens
    Axboe.

 9) Check for DMA mapping errors in starfire driver, from Alexey
    Khoroshilov.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (31 commits)
  tcp: fix 0 divide in __tcp_select_window()
  ipv6: pointer math error in ip6_tnl_parse_tlv_enc_lim()
  net: fix ndo_features_check/ndo_fix_features comment ordering
  net/sched: matchall: Fix configuration race
  be2net: fix initial MAC setting
  ipv6: fix flow labels when the traffic class is non-0
  net: thunderx: avoid dereferencing xcv when NULL
  net/sched: cls_flower: Correct matching on ICMPv6 code
  ipv6: Paritially checksum full MTU frames
  net/mlx4_core: Avoid command timeouts during VF driver device shutdown
  gianfar: synchronize DMA API usage by free_skb_rx_queue w/ gfar_new_page
  net: ethtool: add support for 2500BaseT and 5000BaseT link modes
  can: bcm: fix hrtimer/tasklet termination in bcm op removal
  net: adaptec: starfire: add checks for dma mapping errors
  net: phy: micrel: KSZ8795 do not set SUPPORTED_[Asym_]Pause
  can: Fix kernel panic at security_sock_rcv_skb
  net: macb: Fix 64 bit addressing support for GEM
  stmmac: Discard masked flags in interrupt status register
  net/mlx5e: Check ets capability before ets query FW command
  net/mlx5e: Fix update of hash function/key via ethtool
  ...
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?h=nds-private-remove&amp;id=6d04dfc8966019b8b0977b2cb942351f13d2b178'>Diffstat</a> (limited to 'drivers/usb/host/xhci-trace.h')</div><table summary='diffstat' class='diffstat'>