/* pfmlib_intel_x86_perf.c : perf_event Intel X86 functions

 *

 * Copyright (c) 2011 Google, Inc

 * Contributed by Stephane Eranian <eranian@gmail.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.

 */

#include <sys/types.h>

#include <string.h>

#include <stdlib.h>

#include <stdio.h>

#include <stdarg.h>

#include <limits.h>

/* private headers */

#include "pfmlib_priv.h"

#include "pfmlib_intel_x86_priv.h"

#include "pfmlib_perf_event_priv.h"

static int

find_pmu_type_by_name(const char *name)

{

	char filename[PATH_MAX];

	FILE *fp;

	int ret, type;

	if (!name)

		return PFM_ERR_NOTSUPP;

	sprintf(filename, "/sys/bus/event_source/devices/%s/type", name);

	fp = fopen(filename, "r");

	if (!fp)

		return PFM_ERR_NOTSUPP;

	ret = fscanf(fp, "%d", &type);

	if (ret != 1)

		type = PFM_ERR_NOTSUPP;

	fclose(fp);

	return type;

}

static int

has_ldlat(void *this, pfmlib_event_desc_t *e)

{

	pfmlib_event_attr_info_t *a;

	int i;

	for (i = 0; i < e->nattrs; i++) {

		a = attr(e, i);

		if (a->ctrl != PFM_ATTR_CTRL_PMU)

			continue;

		if (a->type != PFM_ATTR_UMASK)

			continue;

		if (intel_x86_uflag(this, e->event, a->idx, INTEL_X86_LDLAT))

			return 1;

	}

	return 0;

}

int

pfm_intel_x86_get_perf_encoding(void *this, pfmlib_event_desc_t *e)

{

	pfmlib_pmu_t *pmu = this;

	struct perf_event_attr *attr = e->os_data;

	int ret;

	if (!pmu->get_event_encoding[PFM_OS_NONE])

		return PFM_ERR_NOTSUPP;

	/*

	 * first, we need to do the generic encoding

	 */

	ret = pmu->get_event_encoding[PFM_OS_NONE](this, e);

	if (ret != PFM_SUCCESS)

		return ret;

	if (e->count > 2) {

		DPRINT("%s: unsupported count=%d\n", e->count);

		return PFM_ERR_NOTSUPP;

	}

	/* default PMU type */

	attr->type = PERF_TYPE_RAW;

	/*

	 * if PMU specifies a perf PMU name, then grab the type

	 * from sysfs as it is most likely dynamically assigned.

	 * This allows this function to use used by some uncore PMUs

	 */

	if (pmu->perf_name) {

		int type = find_pmu_type_by_name(pmu->perf_name);

		if (type == PFM_ERR_NOTSUPP) {

			DPRINT("perf PMU %s, not supported by OS\n", pmu->perf_name);

		} else {

			DPRINT("PMU %s perf type=%d\n", pmu->name, type);

			attr->type = type;

		}

	}

	attr->config = e->codes[0];

	if (e->count > 1) {

		/*

		 * Nehalem/Westmere/Sandy Bridge OFFCORE_RESPONSE events

		 * take two MSRs. Lower level returns two codes:

		 * - codes[0] goes to regular counter config

		 * - codes[1] goes into extra MSR

		 */

		if (intel_x86_eflag(this, e->event, INTEL_X86_NHM_OFFCORE)) {

			if (e->count != 2) {

				DPRINT("perf_encoding: offcore=1 count=%d\n", e->count);

				return PFM_ERR_INVAL;

			}

			attr->config1 = e->codes[1];

		}

		/*

		 * SkyLake FRONTEND_RETIRED event

		 * takes two MSRs. Lower level returns two codes:

		 * - codes[0] goes to regular counter config

		 * - codes[1] goes into extra MSR

		 */

		if (intel_x86_eflag(this, e->event, INTEL_X86_FRONTEND)) {

			if (e->count != 2) {

				DPRINT("perf_encoding: frontend_retired=1 count=%d\n", e->count);

				return PFM_ERR_INVAL;

			}

			attr->config1 = e->codes[1];

		}

		/*

		 * Load Latency threshold (NHM/WSM/SNB)

		 * - codes[0] goes to regular counter config

		 * - codes[1] LD_LAT MSR value (LSB 16 bits)

		 */

		if (has_ldlat(this, e)) {

			if (e->count != 2) {

				DPRINT("perf_encoding: ldlat count=%d\n", e->count);

				return PFM_ERR_INVAL;

			}

			attr->config1 = e->codes[1];

		}

	}

	return PFM_SUCCESS;

}

int

pfm_intel_nhm_unc_get_perf_encoding(void *this, pfmlib_event_desc_t *e)

{

	pfmlib_pmu_t *pmu = this;

	struct perf_event_attr *attr = e->os_data;

	pfm_intel_x86_reg_t reg;

	int ret;

	if (!pmu->get_event_encoding[PFM_OS_NONE])

		return PFM_ERR_NOTSUPP;

	ret = pmu->get_event_encoding[PFM_OS_NONE](this, e);

	if (ret != PFM_SUCCESS)

		return ret;

	ret = find_pmu_type_by_name(pmu->perf_name);

	if (ret < 0)

		return ret;

	attr->type = ret;

	reg.val = e->codes[0];

	/*

	 * encoder treats all events as using the generic

	 * counters.

	 * perf_events override the enable and int bits, so

	 * drop them here.

	 *

	 * also makes fixed counter special encoding 0xff

	 * work. kernel checking for perfect match.

	 */

	reg.nhm_unc.usel_en  = 0;

	reg.nhm_unc.usel_int = 0;

	attr->config = reg.val;

	/*

	 * uncore measures at all priv levels

	 *

	 * user cannot set per-event priv levels because

	 * attributes are simply not there

	 *

	 * dfl_plm is ignored in this case

	 */

	attr->exclude_hv = 0;

	attr->exclude_kernel = 0;

	attr->exclude_user = 0;

	return PFM_SUCCESS;

}

int

pfm_intel_x86_requesting_pebs(pfmlib_event_desc_t *e)

{

	pfmlib_event_attr_info_t *a;

	int i;

	for (i = 0; i < e->nattrs; i++) {

		a = attr(e, i);

		if (a->ctrl != PFM_ATTR_CTRL_PERF_EVENT)

			continue;

		if (a->idx == PERF_ATTR_PR && e->attrs[i].ival)

			return 1;

	}

	return 0;

}

static int

intel_x86_event_has_pebs(void *this, pfmlib_event_desc_t *e)

{

	pfmlib_event_attr_info_t *a;

	int i;

	/* first check at the event level */

	if (intel_x86_eflag(e->pmu, e->event, INTEL_X86_PEBS))

		return 1;

	/* check umasks */

	for(i=0; i < e->npattrs; i++) {

		a = e->pattrs+i;

		if (a->ctrl != PFM_ATTR_CTRL_PMU || a->type != PFM_ATTR_UMASK)

			continue;

		if (intel_x86_uflag(e->pmu, e->event, a->idx, INTEL_X86_PEBS))

			return 1;

	}

	return 0;

}

/*

 * remove attrs which are in conflicts (or duplicated) with os layer

 */

void

pfm_intel_x86_perf_validate_pattrs(void *this, pfmlib_event_desc_t *e)

{

	pfmlib_pmu_t *pmu = this;

	int i, compact;

	int has_pebs = intel_x86_event_has_pebs(this, e);

	int no_smpl = pmu->flags & PFMLIB_PMU_FL_NO_SMPL;

	for (i = 0; i < e->npattrs; i++) {

		compact = 0;

		/* umasks never conflict */

		if (e->pattrs[i].type == PFM_ATTR_UMASK)

			continue;

		/*

		 * with perf_events, u and k are handled at the OS level

		 * via exclude_user, exclude_kernel.

		 */

		if (e->pattrs[i].ctrl == PFM_ATTR_CTRL_PMU) {

			if (e->pattrs[i].idx == INTEL_X86_ATTR_U

			    || e->pattrs[i].idx == INTEL_X86_ATTR_K)

				compact = 1;

		}

		if (e->pattrs[i].ctrl == PFM_ATTR_CTRL_PERF_EVENT) {

			/* Precise mode, subject to PEBS */

			if (e->pattrs[i].idx == PERF_ATTR_PR && !has_pebs)

				compact = 1;

			/*

			 * No hypervisor on Intel

			 */

			if (e->pattrs[i].idx == PERF_ATTR_H)

				compact = 1;

			if (no_smpl

			    && (   e->pattrs[i].idx == PERF_ATTR_FR

			        || e->pattrs[i].idx == PERF_ATTR_PR

			        || e->pattrs[i].idx == PERF_ATTR_PE))

				compact = 1;

			/*

			 * no priv level support

			 */

			if (pmu->supported_plm == 0

			    && (   e->pattrs[i].idx == PERF_ATTR_U

			        || e->pattrs[i].idx == PERF_ATTR_K

			        || e->pattrs[i].idx == PERF_ATTR_MG

			        || e->pattrs[i].idx == PERF_ATTR_MH))

				compact = 1;

		}

		if (compact) {

			/* e->npattrs modified by call */

			pfmlib_compact_pattrs(e, i);

			/* compensate for i++ */

			i--;

		}

	}

}

int

pfm_intel_x86_perf_detect(void *this)

{

	pfmlib_pmu_t *pmu = this;

	char file[64];

	snprintf(file,sizeof(file), "/sys/devices/%s", pmu->perf_name);

	return access(file, R_OK|X_OK) ? PFM_ERR_NOTSUPP : PFM_SUCCESS;

}