/* Test context switching to see if the DSCR SPR is correctly preserved
 * when within a transaction.
 *
 * Note: We assume that the DSCR has been left at the default value (0)
 * for all CPUs.
 *
 * Method:
 *
 * Set a value into the DSCR.
 *
 * Start a transaction, and suspend it (*).
 *
 * Hard loop checking to see if the transaction has become doomed.
 *
 * Now that we *may* have been preempted, record the DSCR and TEXASR SPRS.
 *
 * If the abort was because of a context switch, check the DSCR value.
 * Otherwise, try again.
 *
 * (*) If the transaction is not suspended we can't see the problem because
 * the transaction abort handler will restore the DSCR to it's checkpointed
 * value before we regain control.
 */

#include <inttypes.h>
#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
#include <asm/tm.h>

#include "utils.h"
#include "tm.h"

#define SPRN_DSCR       0x03

int test_body(void)
{
	uint64_t rv, dscr1 = 1, dscr2, texasr;

	SKIP_IF(!have_htm());

	printf("Check DSCR TM context switch: ");
	fflush(stdout);
	for (;;) {
		rv = 1;
		asm __volatile__ (
			/* set a known value into the DSCR */
			"ld      3, %[dscr1];"
			"mtspr   %[sprn_dscr], 3;"

			/* start and suspend a transaction */
			"tbegin.;"
			"beq     1f;"
			"tsuspend.;"

			/* hard loop until the transaction becomes doomed */
			"2: ;"
			"tcheck 0;"
			"bc      4, 0, 2b;"

			/* record DSCR and TEXASR */
			"mfspr   3, %[sprn_dscr];"
			"std     3, %[dscr2];"
			"mfspr   3, %[sprn_texasr];"
			"std     3, %[texasr];"

			"tresume.;"
			"tend.;"
			"li      %[rv], 0;"
			"1: ;"
			: [rv]"=r"(rv), [dscr2]"=m"(dscr2), [texasr]"=m"(texasr)
			: [dscr1]"m"(dscr1)
			, [sprn_dscr]"i"(SPRN_DSCR), [sprn_texasr]"i"(SPRN_TEXASR)
			: "memory", "r3"
		);
		assert(rv); /* make sure the transaction aborted */
		if ((texasr >> 56) != TM_CAUSE_RESCHED) {
			putchar('.');
			fflush(stdout);
			continue;
		}
		if (dscr2 != dscr1) {
			printf(" FAIL\n");
			return 1;
		} else {
			printf(" OK\n");
			return 0;
		}
	}
}

int main(void)
{
	return test_harness(test_body, "tm_resched_dscr");
}
a><a href='/cgit.cgi/linux/net-next.git/diff/sound/soc/codecs/wl1273.h?h=nds-private-remove&amp;id=482ff9fdc84dd71099d54edb322a2b32d2f331e4'>diff</a></td><td class='form'><form class='right' method='get' action='/cgit.cgi/linux/net-next.git/log/sound/soc/codecs/wl1273.h'>
<input type='hidden' name='h' value='nds-private-remove'/><input type='hidden' name='id' value='482ff9fdc84dd71099d54edb322a2b32d2f331e4'/><select name='qt'>
<option value='grep'>log msg</option>
<option value='author'>author</option>
<option value='committer'>committer</option>
<option value='range'>range</option>
</select>
<input class='txt' type='search' size='10' name='q' value=''/>
<input type='submit' value='search'/>
</form>
</td></tr></table>
<div class='path'>path: <a href='/cgit.cgi/linux/net-next.git/log/?h=nds-private-remove&amp;id=482ff9fdc84dd71099d54edb322a2b32d2f331e4'>root</a>/<a href='/cgit.cgi/linux/net-next.git/log/sound?h=nds-private-remove&amp;id=482ff9fdc84dd71099d54edb322a2b32d2f331e4'>sound</a>/<a href='/cgit.cgi/linux/net-next.git/log/sound/soc?h=nds-private-remove&amp;id=482ff9fdc84dd71099d54edb322a2b32d2f331e4'>soc</a>/<a href='/cgit.cgi/linux/net-next.git/log/sound/soc/codecs?h=nds-private-remove&amp;id=482ff9fdc84dd71099d54edb322a2b32d2f331e4'>codecs</a>/<a href='/cgit.cgi/linux/net-next.git/log/sound/soc/codecs/wl1273.h?h=nds-private-remove&amp;id=482ff9fdc84dd71099d54edb322a2b32d2f331e4'>wl1273.h</a></div><div class='content'><table class='list nowrap'><tr class='nohover'><th class='left'>Age</th><th class='left'>Commit message (<a href='/cgit.cgi/linux/net-next.git/log/sound/soc/codecs/wl1273.h?h=nds-private-remove&amp;id=482ff9fdc84dd71099d54edb322a2b32d2f331e4&amp;showmsg=1'>Expand</a>)</th><th class='left'>Author</th><th class='left'>Files</th><th class='left'>Lines</th></tr>