/*
* self_view.c - example of self-monitoring with PMD access via remapping
*
* Copyright (c) 2005-2006 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.
*/
#include <sys/types.h>
#include <inttypes.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <errno.h>
#include <unistd.h>
#include <string.h>
#include <signal.h>
#include <sys/mman.h>
#include <perfmon/pfmlib.h>
#include <perfmon/perfmon.h>
#include "detect_pmcs.h"
#define NUM_PMCS PFMLIB_MAX_PMCS
#define NUM_PMDS PFMLIB_MAX_PMDS
#define MAX_EVT_NAME_LEN 128
typedef struct {
uint64_t val;
unsigned int reg_num;
char name[MAX_EVT_NAME_LEN];
} pmd_val_t;
static pfm_set_view_t *view0;
static pmd_val_t pmdv[NUM_PMDS];
static unsigned int num_pmdv;
static uint64_t ovfl_mask;
static void fatal_error(char *fmt,...) __attribute__((noreturn));
static void
fatal_error(char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
vfprintf(stderr, fmt, ap);
va_end(ap);
exit(1);
}
#ifdef __ia64__
#define get_pmd(n) ia64_get_pmd(n)
#elif defined(__x86_64__) || defined(__i386__)
/*
* IMPORTANT:
* there is an implicit assumption here that the perfmon-2
* PMD mapping and the rdpmc mapping correspond. As such
* pmd0 -> rdpmc(0)
* pmd1 -> rdpmc(1)
* ...
*/
#define rdpmc(counter,low,high) \
__asm__ __volatile__("rdpmc" \
: "=a" (low), "=d" (high) \
: "c" (counter))
uint64_t
get_pmd(unsigned int n)
{
uint32_t high, low;
uint64_t tmp;
rdpmc(n, low, high);
tmp = (uint64_t)high <<32 | low;
return tmp;
}
#elif defined(__mips__) || defined(__powerpc__)
/*
* XXX: MIPS does not have an instruction to read a counter at the user level
*/
uint64_t
get_pmd(unsigned int n)
{
return(0ULL);
}
#else
#error "you need to define get_pmd for your architecture"
#endif
static void
show_view_self(int is_loaded)
{
unsigned int i, is_active;
uint64_t val, hw_val;
uint64_t mask = ovfl_mask;
unsigned long retries = 0;
unsigned long start_seq, end_seq;
retries = -1;
/*
* print the results
*/
retry:
retries++;
/*
* get initial sequence number, if the number changes
* while we are scanning, it means the view was updated
* and we need to retry
*/
start_seq = view0->set_seq;
/*
* active is true if the set is the active set
*/
is_active = view0->set_status & PFM_SETVFL_ACTIVE;
printf("retries=%lu active=%d view_seq=%lu set_runs=%"PRIu64"\n",
retries,
view0->set_status,
view0->set_seq,
view0->set_runs);
/*
* extract information directly from view
*/
for (i=0; i < num_pmdv; i++) {
val = view0->set_pmds[pmdv[i].reg_num];
/*
* is context is attached and set is active then
* we need to complement the software value with
* the current hardware value. For self-monitoring
* with simply need to read the PMD
*/
if (is_loaded && is_active) {
hw_val = get_pmd(pmdv[i].reg_num);
/*
* update the lower portion of the 64-bit
* value with the hardware value
*/
val = (val & ~mask) | (hw_val & mask);
}
pmdv[i].val = val;
}
/*
* check if sequence number is still the same
*/
end_seq = view0->set_seq;
if (end_seq != start_seq) goto retry;
/*
* print results
*/
for (i=0; i < num_pmdv; i++) {
printf("%20"PRIu64" %s\n", pmdv[i].val, pmdv[i].name);
}
}
uint64_t
noploop(uint64_t loop)
{
while (loop--) {
if ((loop % 10000) == 0) show_view_self(1);
}
return loop;
}
int
main(int argc, char **argv)
{
char **p;
unsigned int i;
int ret, ctx_fd;
pfmlib_input_param_t inp;
pfmlib_output_param_t outp;
pfarg_pmd_t pd[NUM_PMDS];
pfarg_pmc_t pc[NUM_PMCS];
pfarg_ctx_t ctx[1];
pfarg_setinfo_t setinfo;
pfarg_load_t load_args;
pfmlib_options_t pfmlib_options;
unsigned int num_counters, width;
#ifdef __mips__
printf("<<WARNING: MIPS does not have an instruction to read a counter at the user level. Results are wrong>>\n");
#endif
/*
* pass options to library (optional)
*/
memset(&pfmlib_options, 0, sizeof(pfmlib_options));
pfmlib_options.pfm_debug = 0; /* set to 1 for debug */
pfmlib_options.pfm_verbose = 1; /* set to 1 for debug */
pfm_set_options(&pfmlib_options);
/*
* Initialize pfm library (required before we can use it)
*/
ret = pfm_initialize();
if (ret != PFMLIB_SUCCESS)
fatal_error("Cannot initialize library: %s\n", pfm_strerror(ret));
pfm_get_num_counters(&num_counters);
pfm_get_hw_counter_width(&width);
ovfl_mask = (1ULL << width)-1;
printf("width=%u ovfl_mask=0x%"PRIx64"\n", width, ovfl_mask);
memset(pd, 0, sizeof(pd));
memset(pc, 0, sizeof(pc));
memset(ctx, 0, sizeof(ctx));
memset(&load_args, 0, sizeof(load_args));
memset(&setinfo, 0, sizeof(setinfo));
/*
* prepare parameters to library. we don't use any Itanium
* specific features here. so the pfp_model is NULL.
*/
memset(&inp,0, sizeof(inp));
memset(&outp,0, sizeof(outp));
/*
* be nice to user!
*/
if (argc > 1) {
p = argv+1;
for (i=0; *p ; i++, p++) {
if (pfm_find_full_event(*p, &inp.pfp_events[i]) != PFMLIB_SUCCESS) {
fatal_error("Cannot find %s event\n", *p);
}
}
} else {
if (pfm_get_cycle_event(&inp.pfp_events[0]) != PFMLIB_SUCCESS) {
fatal_error("cannot find cycle event\n");
}
if (pfm_get_inst_retired_event(&inp.pfp_events[1]) != PFMLIB_SUCCESS) {
fatal_error("cannot find inst retired event\n");
}
i = 2;
}
/*
* set the default privilege mode for all counters:
* PFM_PLM3 : user level only
*/
inp.pfp_dfl_plm = PFM_PLM3;
if (i > num_counters) {
i = num_counters;
printf("too many events provided (max=%d events), using first %d event(s)\n", num_counters, i);
}
/*
* how many counters we use
*/
inp.pfp_event_count = i;
ctx[0].ctx_flags = PFM_FL_MAP_SETS;
/*
* now create a new context, per process context.
* This just creates a new context with some initial state, it is not
* active nor attached to any process.
*/
ctx_fd = pfm_create_context(ctx, NULL, NULL, 0);
if (ctx_fd == -1) {
if (errno == ENOSYS) {
fatal_error("Your kernel does not have performance monitoring support!\n");
}
fatal_error("Can't create PFM context %s\n", strerror(errno));
}
/*
* build the pfp_unavail_pmcs bitmask by looking
* at what perfmon has available. It is not always
* the case that all PMU registers are actually available
* to applications. For instance, on IA-32 platforms, some
* registers may be reserved for the NMI watchdog timer.
*
* With this bitmap, the library knows which registers NOT to
* use. Of source, it is possible that no valid assignement may
* be possible if certina PMU registers are not available.
*/
detect_unavail_pmcs(ctx_fd, &inp.pfp_unavail_pmcs);
/*
* let the library figure out the values for the PMCS
*/
if ((ret=pfm_dispatch_events(&inp, NULL, &outp, NULL)) != PFMLIB_SUCCESS) {
fatal_error("cannot configure events: %s\n", pfm_strerror(ret));
}
/*
* Now prepare the argument to initialize the PMDs and PMCS.
* We must pfp_pmc_count to determine the number of PMC to intialize.
* We must use pfp_event_count to determine the number of PMD to initialize.
* Some events causes extra PMCs to be used, so pfp_pmc_count may be >= pfp_event_count.
*
* This step is new compared to libpfm-2.x. It is necessary because the library no
* longer knows about the kernel data structures.
*/
for (i=0; i < outp.pfp_pmc_count; i++) {
pc[i].reg_num = outp.pfp_pmcs[i].reg_num;
pc[i].reg_value = outp.pfp_pmcs[i].reg_value;
}
for(i=0; i < outp.pfp_pmd_count; i++)
pd[i].reg_num = outp.pfp_pmds[i].reg_num;
/*
* Now program the registers
*
* We don't use the same variable to indicate the number of elements passed to
* the kernel because, as we said earlier, pc may contain more elements than
* the number of events (pmd) we specified, i.e., contains more than counting
* monitors.
*/
if (pfm_write_pmcs(ctx_fd, pc, outp.pfp_pmc_count))
fatal_error("pfm_write_pmcs error errno %d\n",errno);
/*
* To be read, each PMD must be either written or declared
* as being part of a sample (reg_smpl_pmds)
*/
if (pfm_write_pmds(ctx_fd, pd, outp.pfp_pmd_count))
fatal_error("pfm)write_pmds error errno %d\n",errno);
/*
* now we load (i.e., attach) the context to ourself
*/
load_args.load_pid = getpid();
if (pfm_load_context(ctx_fd, &load_args))
fatal_error("pfm_load_context error errno %d\n",errno);
/*
* retrieve set0 information
*/
if (pfm_getinfo_evtsets(ctx_fd, &setinfo, 1))
fatal_error("pfm_getinfo_evtsets error errno %d\n",errno);
printf("set_id=0 mmap_offset=%llu\n", (unsigned long long)setinfo.set_mmap_offset);
view0 = (pfm_set_view_t *)mmap(NULL, getpagesize(), PROT_READ, MAP_PRIVATE, ctx_fd, setinfo.set_mmap_offset);
if (view0 == MAP_FAILED) {
fatal_error("cannot mmap set view errno %d\n", errno);
}
printf("view=%p set_id=0 set_status=%u\n", view0, view0->set_status);
/*
* Let's roll now
*/
pfm_self_start(ctx_fd);
noploop(10000000);
pfm_self_stop(ctx_fd);
/*
* unload context (stop + unload)
*/
if (pfm_unload_context(ctx_fd))
fatal_error( "pfm_unload_context error errno %d\n",errno);
/*
* now read the results
*/
if (pfm_read_pmds(ctx_fd, pd, outp.pfp_pmd_count))
fatal_error( "pfm_read_pmds error errno %d\n",errno);
printf("results using pfm_read_pmds:\n");
for (i=0; i < num_pmdv; i++) {
printf("%20"PRIu64" %s\n", pd[i].reg_value, pmdv[i].name);
}
show_view_self(0);
/*
* and destroy our context
*/
munmap(view0, getpagesize());
close(ctx_fd);
return 0;
}