/*
 * Tests for prctl(PR_GET_TSC, ...) / prctl(PR_SET_TSC, ...)
 *
 * Tests if the control register is updated correctly
 * when set with prctl()
 *
 * Warning: this test will cause a very high load for a few seconds
 *
 */

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <signal.h>
#include <inttypes.h>
#include <wait.h>


#include <sys/prctl.h>
#include <linux/prctl.h>

/* Get/set the process' ability to use the timestamp counter instruction */
#ifndef PR_GET_TSC
#define PR_GET_TSC 25
#define PR_SET_TSC 26
# define PR_TSC_ENABLE		1   /* allow the use of the timestamp counter */
# define PR_TSC_SIGSEGV		2   /* throw a SIGSEGV instead of reading the TSC */
#endif

/* snippet from wikipedia :-) */

static uint64_t rdtsc(void)
{
uint32_t lo, hi;
/* We cannot use "=A", since this would use %rax on x86_64 */
__asm__ __volatile__ ("rdtsc" : "=a" (lo), "=d" (hi));
return (uint64_t)hi << 32 | lo;
}

int should_segv = 0;

static void sigsegv_cb(int sig)
{
	if (!should_segv)
	{
		fprintf(stderr, "FATAL ERROR, rdtsc() failed while enabled\n");
		exit(0);
	}
	if (prctl(PR_SET_TSC, PR_TSC_ENABLE) < 0)
	{
		perror("prctl");
		exit(0);
	}
	should_segv = 0;

	rdtsc();
}

static void task(void)
{
	signal(SIGSEGV, sigsegv_cb);
	alarm(10);
	for(;;)
	{
		rdtsc();
		if (should_segv)
		{
			fprintf(stderr, "FATAL ERROR, rdtsc() succeeded while disabled\n");
			exit(0);
		}
		if (prctl(PR_SET_TSC, PR_TSC_SIGSEGV) < 0)
		{
			perror("prctl");
			exit(0);
		}
		should_segv = 1;
	}
}


int main(void)
{
	int n_tasks = 100, i;

	fprintf(stderr, "[No further output means we're allright]\n");

	for (i=0; i<n_tasks; i++)
		if (fork() == 0)
			task();

	for (i=0; i<n_tasks; i++)
		wait(NULL);

	exit(0);
}

ext.git/log/drivers/usb/host/ohci-sm501.c'>log</a><a href='/cgit.cgi/linux/net-next.git/tree/drivers/usb/host/ohci-sm501.c?id=697d3a21615672b2bf7724a65755799260325dda'>tree</a><a class='active' href='/cgit.cgi/linux/net-next.git/commit/drivers/usb/host/ohci-sm501.c?id=697d3a21615672b2bf7724a65755799260325dda'>commit</a><a href='/cgit.cgi/linux/net-next.git/diff/drivers/usb/host/ohci-sm501.c?id=697d3a21615672b2bf7724a65755799260325dda'>diff</a></td><td class='form'><form class='right' method='get' action='/cgit.cgi/linux/net-next.git/log/drivers/usb/host/ohci-sm501.c'>
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<div class='path'>path: <a href='/cgit.cgi/linux/net-next.git/commit/?id=697d3a21615672b2bf7724a65755799260325dda'>root</a>/<a href='/cgit.cgi/linux/net-next.git/commit/drivers?id=697d3a21615672b2bf7724a65755799260325dda'>drivers</a>/<a href='/cgit.cgi/linux/net-next.git/commit/drivers/usb?id=697d3a21615672b2bf7724a65755799260325dda'>usb</a>/<a href='/cgit.cgi/linux/net-next.git/commit/drivers/usb/host?id=697d3a21615672b2bf7724a65755799260325dda'>host</a>/<a href='/cgit.cgi/linux/net-next.git/commit/drivers/usb/host/ohci-sm501.c?id=697d3a21615672b2bf7724a65755799260325dda'>ohci-sm501.c</a></div><div class='content'><div class='cgit-panel'><b>diff options</b><form method='get'><input type='hidden' name='id' value='697d3a21615672b2bf7724a65755799260325dda'/><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>Dave Airlie &lt;airlied@redhat.com&gt;</td><td class='right'>2017-02-10 10:14:24 +1000</td></tr>
<tr><th>committer</th><td>Dave Airlie &lt;airlied@redhat.com&gt;</td><td class='right'>2017-02-10 10:14:24 +1000</td></tr>
<tr><th>commit</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/drivers/usb/host/ohci-sm501.c?id=697d3a21615672b2bf7724a65755799260325dda'>697d3a21615672b2bf7724a65755799260325dda</a> (<a href='/cgit.cgi/linux/net-next.git/patch/drivers/usb/host/ohci-sm501.c?id=697d3a21615672b2bf7724a65755799260325dda'>patch</a>)</td></tr>
<tr><th>tree</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/tree/?id=697d3a21615672b2bf7724a65755799260325dda'>79dfa1b95274ee71e9d8c4a35b377f88d1cdd9e0</a> /<a href='/cgit.cgi/linux/net-next.git/tree/drivers/usb/host/ohci-sm501.c?id=697d3a21615672b2bf7724a65755799260325dda'>drivers/usb/host/ohci-sm501.c</a></td></tr>
<tr><th>parent</th><td colspan='2' class='oid'><a href='/cgit.cgi/linux/net-next.git/commit/drivers/usb/host/ohci-sm501.c?id=811b40c83db047ba22a0c5b638186ed2b8c9810c'>811b40c83db047ba22a0c5b638186ed2b8c9810c</a> (<a href='/cgit.cgi/linux/net-next.git/diff/drivers/usb/host/ohci-sm501.c?id=697d3a21615672b2bf7724a65755799260325dda&amp;id2=811b40c83db047ba22a0c5b638186ed2b8c9810c'>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/ohci-sm501.c?id=6e7eb1783be7f19eb071c96ddda0bbf22279ff46'>6e7eb1783be7f19eb071c96ddda0bbf22279ff46</a> (<a href='/cgit.cgi/linux/net-next.git/diff/drivers/usb/host/ohci-sm501.c?id=697d3a21615672b2bf7724a65755799260325dda&amp;id2=6e7eb1783be7f19eb071c96ddda0bbf22279ff46'>diff</a>)</td></tr></table>
<div class='commit-subject'>Merge tag 'drm-intel-fixes-2017-02-09' of git://anongit.freedesktop.org/git/drm-intel into drm-fixes</div><div class='commit-msg'>Hopefully final fixes for v4.10, about half of them stable material.

* tag 'drm-intel-fixes-2017-02-09' of git://anongit.freedesktop.org/git/drm-intel:
  drm/i915: Always convert incoming exec offsets to non-canonical
  drm/i915: Remove overzealous fence warn on runtime suspend
  drm/i915/bxt: Add MST support when do DPLL calculation
  drm/i915: don't warn about Skylake CPU - KabyPoint PCH combo
  drm/i915: fix i915 running as dom0 under Xen
  drm/i915: Flush untouched framebuffers before display on !llc
  drm/i915: fix use-after-free in page_flip_completed()
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?id=697d3a21615672b2bf7724a65755799260325dda'>Diffstat</a> (limited to 'drivers/usb/host/ohci-sm501.c')</div><table summary='diffstat' class='diffstat'>