#include "util.h"
#include "../perf.h"
#include <subcmd/parse-options.h>
#include "evsel.h"
#include "cgroup.h"
#include "evlist.h"

int nr_cgroups;

static int
cgroupfs_find_mountpoint(char *buf, size_t maxlen)
{
	FILE *fp;
	char mountpoint[PATH_MAX + 1], tokens[PATH_MAX + 1], type[PATH_MAX + 1];
	char *token, *saved_ptr = NULL;
	int found = 0;

	fp = fopen("/proc/mounts", "r");
	if (!fp)
		return -1;

	/*
	 * in order to handle split hierarchy, we need to scan /proc/mounts
	 * and inspect every cgroupfs mount point to find one that has
	 * perf_event subsystem
	 */
	while (fscanf(fp, "%*s %"STR(PATH_MAX)"s %"STR(PATH_MAX)"s %"
				STR(PATH_MAX)"s %*d %*d\n",
				mountpoint, type, tokens) == 3) {

		if (!strcmp(type, "cgroup")) {

			token = strtok_r(tokens, ",", &saved_ptr);

			while (token != NULL) {
				if (!strcmp(token, "perf_event")) {
					found = 1;
					break;
				}
				token = strtok_r(NULL, ",", &saved_ptr);
			}
		}
		if (found)
			break;
	}
	fclose(fp);
	if (!found)
		return -1;

	if (strlen(mountpoint) < maxlen) {
		strcpy(buf, mountpoint);
		return 0;
	}
	return -1;
}

static int open_cgroup(char *name)
{
	char path[PATH_MAX + 1];
	char mnt[PATH_MAX + 1];
	int fd;


	if (cgroupfs_find_mountpoint(mnt, PATH_MAX + 1))
		return -1;

	snprintf(path, PATH_MAX, "%s/%s", mnt, name);

	fd = open(path, O_RDONLY);
	if (fd == -1)
		fprintf(stderr, "no access to cgroup %s\n", path);

	return fd;
}

static int add_cgroup(struct perf_evlist *evlist, char *str)
{
	struct perf_evsel *counter;
	struct cgroup_sel *cgrp = NULL;
	int n;
	/*
	 * check if cgrp is already defined, if so we reuse it
	 */
	evlist__for_each_entry(evlist, counter) {
		cgrp = counter->cgrp;
		if (!cgrp)
			continue;
		if (!strcmp(cgrp->name, str))
			break;

		cgrp = NULL;
	}

	if (!cgrp) {
		cgrp = zalloc(sizeof(*cgrp));
		if (!cgrp)
			return -1;

		cgrp->name = str;

		cgrp->fd = open_cgroup(str);
		if (cgrp->fd == -1) {
			free(cgrp);
			return -1;
		}
	}

	/*
	 * find corresponding event
	 * if add cgroup N, then need to find event N
	 */
	n = 0;
	evlist__for_each_entry(evlist, counter) {
		if (n == nr_cgroups)
			goto found;
		n++;
	}
	if (atomic_read(&cgrp->refcnt) == 0)
		free(cgrp);

	return -1;
found:
	atomic_inc(&cgrp->refcnt);
	counter->cgrp = cgrp;
	return 0;
}

void close_cgroup(struct cgroup_sel *cgrp)
{
	if (cgrp && atomic_dec_and_test(&cgrp->refcnt)) {
		close(cgrp->fd);
		zfree(&cgrp->name);
		free(cgrp);
	}
}

int parse_cgroups(const struct option *opt __maybe_unused, const char *str,
		  int unset __maybe_unused)
{
	struct perf_evlist *evlist = *(struct perf_evlist **)opt->value;
	const char *p, *e, *eos = str + strlen(str);
	char *s;
	int ret;

	if (list_empty(&evlist->entries)) {
		fprintf(stderr, "must define events before cgroups\n");
		return -1;
	}

	for (;;) {
		p = strchr(str, ',');
		e = p ? p : eos;

		/* allow empty cgroups, i.e., skip */
		if (e - str) {
			/* termination added */
			s = strndup(str, e - str);
			if (!s)
				return -1;
			ret = add_cgroup(evlist, s);
			if (ret) {
				free(s);
				return -1;
			}
		}
		/* nr_cgroups is increased een for empty cgroups */
		nr_cgroups++;
		if (!p)
			break;
		str = p+1;
	}
	return 0;
}
t/drivers/usb/musb/musb_host.c?id=0becc0ae5b42828785b589f686725ff5bc3b9b25'>musb_host.c</a></div><div class='content'><div class='cgit-panel'><b>diff options</b><form method='get'><input type='hidden' name='id' value='0becc0ae5b42828785b589f686725ff5bc3b9b25'/><table><tr><td colspan='2'/></tr><tr><td class='label'>context:</td><td class='ctrl'><select name='context' onchange='this.form.submit();'><option value='1'>1</option><option value='2'>2</option><option value='3' selected='selected'>3</option><option value='4'>4</option><option value='5'>5</option><option value='6'>6</option><option value='7'>7</option><option value='8'>8</option><option value='9'>9</option><option value='10'>10</option><option value='15'>15</option><option value='20'>20</option><option value='25'>25</option><option value='30'>30</option><option value='35'>35</option><option value='40'>40</option></select></td></tr><tr><td class='label'>space:</td><td class='ctrl'><select name='ignorews' onchange='this.form.submit();'><option value='0' selected='selected'>include</option><option value='1'>ignore</option></select></td></tr><tr><td class='label'>mode:</td><td class='ctrl'><select name='dt' onchange='this.form.submit();'><option value='0' selected='selected'>unified</option><option value='1'>ssdiff</option><option value='2'>stat only</option></select></td></tr><tr><td/><td class='ctrl'><noscript><input type='submit' value='reload'/></noscript></td></tr></table></form></div><table summary='commit info' class='commit-info'>
<tr><th>author</th><td>Thomas Gleixner &lt;tglx@linutronix.de&gt;</td><td class='right'>2017-01-31 09:37:34 +0100</td></tr>
<tr><th>committer</th><td>Thomas Gleixner &lt;tglx@linutronix.de&gt;</td><td class='right'>2017-01-31 21:47:58 +0100</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/drivers/usb/musb/musb_host.c?id=0becc0ae5b42828785b589f686725ff5bc3b9b25'>0becc0ae5b42828785b589f686725ff5bc3b9b25</a> (<a href='/cgit.cgi/linux/net-next.git/patch/drivers/usb/musb/musb_host.c?id=0becc0ae5b42828785b589f686725ff5bc3b9b25'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?id=0becc0ae5b42828785b589f686725ff5bc3b9b25'>be6d0e1f37c38ed0a7dd5da2d4b1e93f0fb43101</a> /<a href='/cgit.cgi/linux/net-next.git/tree/drivers/usb/musb/musb_host.c?id=0becc0ae5b42828785b589f686725ff5bc3b9b25'>drivers/usb/musb/musb_host.c</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/drivers/usb/musb/musb_host.c?id=24c2503255d35c269b67162c397a1a1c1e02f6ce'>24c2503255d35c269b67162c397a1a1c1e02f6ce</a> (<a href='/cgit.cgi/linux/net-next.git/diff/drivers/usb/musb/musb_host.c?id=0becc0ae5b42828785b589f686725ff5bc3b9b25&amp;id2=24c2503255d35c269b67162c397a1a1c1e02f6ce'>diff</a>)</td></tr></table>
<div class='commit-subject'>x86/mce: Make timer handling more robust</div><div class='commit-msg'>Erik reported that on a preproduction hardware a CMCI storm triggers the
BUG_ON in add_timer_on(). The reason is that the per CPU MCE timer is
started by the CMCI logic before the MCE CPU hotplug callback starts the
timer with add_timer_on(). So the timer is already queued which triggers
the BUG.

Using add_timer_on() is pretty pointless in this code because the timer is
strictlty per CPU, initialized as pinned and all operations which arm the
timer happen on the CPU to which the timer belongs.

Simplify the whole machinery by using mod_timer() instead of add_timer_on()
which avoids the problem because mod_timer() can handle already queued
timers. Use __start_timer() everywhere so the earliest armed expiry time is
preserved.

Reported-by: Erik Veijola &lt;erik.veijola@intel.com&gt;
Tested-by: Borislav Petkov &lt;bp@alien8.de&gt;
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Reviewed-by: Borislav Petkov &lt;bp@alien8.de&gt;
Cc: Tony Luck &lt;tony.luck@intel.com&gt;
Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1701310936080.3457@nanos
Signed-off-by: Thomas Gleixner &lt;tglx@linutronix.de&gt;

</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?id=0becc0ae5b42828785b589f686725ff5bc3b9b25'>Diffstat</a> (limited to 'drivers/usb/musb/musb_host.c')</div><table summary='diffstat' class='diffstat'>