/*
* detect_pmu_regs.c - detect unavailable PMD/PMC registers based on perfmon2 information
*
* Copyright (c) 2006-2007 Hewlett-Packard Development Company, L.P.
* Contributed by Stephane Eranian <eranian@hpl.hp.com>
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
* of the Software, and to permit persons to whom the Software is furnished to do so,
* subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
* INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
* CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE
* OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
* This file is part of libpfm, a performance monitoring support library for
* applications on Linux.
*/
#include <sys/types.h>
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <unistd.h>
#include <perfmon/perfmon.h>
#include <perfmon/pfmlib.h>
/*
* The goal of this function is to help pfm_dispatch_events()
* in situations where not all PMC/PMD registers are available.
*
* It builds bitmasks of *unavailable* PMC/PMD registers.
* It can use an existing perfmon context file descriptor or if
* non is passed, it will create a temporary context to retrieve
* the information.
*
* Note that there is no guarantee that the registers marked
* as available will actually be available by the time the perfmon
* context is loaded.
*
* arguments:
* fd : a perfmon context file descriptor, or -1
* r_pmcs: a bitmask for PMC availability, NULL if not needed
* r_pmcs: a bitmask for PMD availability, NULL if not needed
*
* return:
* -1: invalid file descriptor passed or cannot retrieve information
* 0: success
*/
int
detect_unavail_pmu_regs(int fd, pfmlib_regmask_t *r_pmcs, pfmlib_regmask_t *r_pmds)
{
pfarg_ctx_t ctx;
pfarg_setinfo_t setf;
int ret, i, j, myfd, max;
memset(&ctx, 0, sizeof(ctx));
memset(&setf, 0, sizeof(setf));
if (r_pmcs)
memset(r_pmcs, 0, sizeof(*r_pmcs));
if (r_pmds)
memset(r_pmds, 0, sizeof(*r_pmds));
/*
* if no context descriptor is passed, then create
* a temporary context
*/
if (fd == -1) {
myfd = pfm_create_context(&ctx, NULL, NULL, 0);
if (myfd == -1)
return -1;
} else {
myfd = fd;
}
/*
* retrieve available register bitmasks from set0
* which is guaranteed to exist for every context
*
* if myfd is bogus (passed by user) then we return
* an error.
*/
ret = pfm_getinfo_evtsets(myfd, &setf, 1);
if (ret == 0) {
if (r_pmcs) {
max = PFMLIB_REG_BV < PFM_PMC_BV ? PFMLIB_REG_BV : PFM_PMC_BV;
for(i=0; i < max; i++) {
for(j=0; j < 64; j++) {
if ((setf.set_avail_pmcs[i] & (1ULL << j)) == 0)
pfm_regmask_set(r_pmcs, (i<<6)+j);
}
}
}
if (r_pmds) {
max = PFMLIB_REG_BV < PFM_PMD_BV ? PFMLIB_REG_BV : PFM_PMD_BV;
for(i=0; i < max; i++) {
for(j=0; j < 64; j++) {
if ((setf.set_avail_pmds[i] & (1ULL << j)) == 0)
pfm_regmask_set(r_pmds, (i<<6)+j);
}
}
}
}
if (fd == -1)
close(myfd);
return ret;
}