//--------------------------------------------------------------------*/
//--- Massif: a heap profiling tool. ms_main.c ---*/
//--------------------------------------------------------------------*/
/*
This file is part of Massif, a Valgrind tool for profiling memory
usage of programs.
Copyright (C) 2003-2017 Nicholas Nethercote
njn@valgrind.org
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307, USA.
The GNU General Public License is contained in the file COPYING.
*/
//---------------------------------------------------------------------------
// XXX:
//---------------------------------------------------------------------------
// Todo -- nice, but less critical:
// - do a graph-drawing test
// - make file format more generic. Obstacles:
// - unit prefixes are not generic
// - preset column widths for stats are not generic
// - preset column headers are not generic
// - "Massif arguments:" line is not generic
// - do snapshots on some specific client requests
// - "show me the extra allocations since the last snapshot"
// - "start/stop logging" (eg. quickly skip boring bits)
// - Add ability to draw multiple graphs, eg. heap-only, stack-only, total.
// Give each graph a title. (try to do it generically!)
// - make --show-below-main=no work
// - Options like --alloc-fn='operator new(unsigned, std::nothrow_t const&)'
// don't work in a .valgrindrc file or in $VALGRIND_OPTS.
// m_commandline.c:add_args_from_string() needs to respect single quotes.
// - With --stack=yes, want to add a stack trace for detailed snapshots so
// it's clear where/why the peak is occurring. (Mattieu Castet) Also,
// possibly useful even with --stack=no? (Andi Yin)
//
// Performance:
// - To run the benchmarks:
//
// perl perf/vg_perf --tools=massif --reps=3 perf/{heap,tinycc} massif
// time valgrind --tool=massif --depth=100 konqueror
//
// The other benchmarks don't do much allocation, and so give similar speeds
// to Nulgrind.
//
// Timing results on 'nevermore' (njn's machine) as of r7013:
//
// heap 0.53s ma:12.4s (23.5x, -----)
// tinycc 0.46s ma: 4.9s (10.7x, -----)
// many-xpts 0.08s ma: 2.0s (25.0x, -----)
// konqueror 29.6s real 0:21.0s user
//
// [Introduction of --time-unit=i as the default slowed things down by
// roughly 0--20%.]
//
// Todo -- low priority:
// - In each XPt, record both bytes and the number of allocations, and
// possibly the global number of allocations.
// - (Andy Lin) Give a stack trace on detailed snapshots?
// - (Artur Wisz) add a feature to Massif to ignore any heap blocks larger
// than a certain size! Because: "linux's malloc allows to set a
// MMAP_THRESHOLD value, so we set it to 4096 - all blocks above that will
// be handled directly by the kernel, and are guaranteed to be returned to
// the system when freed. So we needed to profile only blocks below this
// limit."
//
// File format working notes:
#if 0
desc: --heap-admin=foo
cmd: date
time_unit: ms
#-----------
snapshot=0
#-----------
time=0
mem_heap_B=0
mem_heap_admin_B=0
mem_stacks_B=0
heap_tree=empty
#-----------
snapshot=1
#-----------
time=353
mem_heap_B=5
mem_heap_admin_B=0
mem_stacks_B=0
heap_tree=detailed
n1: 5 (heap allocation functions) malloc/new/new[], --alloc-fns, etc.
n1: 5 0x27F6E0: _nl_normalize_codeset (in /lib/libc-2.3.5.so)
n1: 5 0x279DE6: _nl_load_locale_from_archive (in /lib/libc-2.3.5.so)
n1: 5 0x278E97: _nl_find_locale (in /lib/libc-2.3.5.so)
n1: 5 0x278871: setlocale (in /lib/libc-2.3.5.so)
n1: 5 0x8049821: (within /bin/date)
n0: 5 0x26ED5E: (below main) (in /lib/libc-2.3.5.so)
n_events: n time(ms) total(B) useful-heap(B) admin-heap(B) stacks(B)
t_events: B
n 0 0 0 0 0
n 0 0 0 0 0
t1: 5 <string...>
t1: 6 <string...>
Ideas:
- each snapshot specifies an x-axis value and one or more y-axis values.
- can display the y-axis values separately if you like
- can completely separate connection between snapshots and trees.
Challenges:
- how to specify and scale/abbreviate units on axes?
- how to combine multiple values into the y-axis?
--------------------------------------------------------------------------------Command: date
Massif arguments: --heap-admin=foo
ms_print arguments: massif.out
--------------------------------------------------------------------------------
KB
6.472^ :#
| :# :: . .
...
| ::@ :@ :@ :@:::# :: : ::::
0 +-----------------------------------@---@---@-----@--@---#-------------->ms 0 713
Number of snapshots: 50
Detailed snapshots: [2, 11, 13, 19, 25, 32 (peak)]
-------------------------------------------------------------------------------- n time(ms) total(B) useful-heap(B) admin-heap(B) stacks(B)
-------------------------------------------------------------------------------- 0 0 0 0 0 0
1 345 5 5 0 0
2 353 5 5 0 0
100.00% (5B) (heap allocation functions) malloc/new/new[], --alloc-fns, etc.
->100.00% (5B) 0x27F6E0: _nl_normalize_codeset (in /lib/libc-2.3.5.so)
#endif
//---------------------------------------------------------------------------
#include "pub_tool_basics.h"
#include "pub_tool_vki.h"
#include "pub_tool_aspacemgr.h"
#include "pub_tool_debuginfo.h"
#include "pub_tool_hashtable.h"
#include "pub_tool_libcbase.h"
#include "pub_tool_libcassert.h"
#include "pub_tool_libcfile.h"
#include "pub_tool_libcprint.h"
#include "pub_tool_libcproc.h"
#include "pub_tool_machine.h"
#include "pub_tool_mallocfree.h"
#include "pub_tool_options.h"
#include "pub_tool_poolalloc.h"
#include "pub_tool_replacemalloc.h"
#include "pub_tool_stacktrace.h"
#include "pub_tool_threadstate.h"
#include "pub_tool_tooliface.h"
#include "pub_tool_xarray.h"
#include "pub_tool_xtree.h"
#include "pub_tool_xtmemory.h"
#include "pub_tool_clientstate.h"
#include "pub_tool_gdbserver.h"
#include "pub_tool_clreq.h" // For {MALLOC,FREE}LIKE_BLOCK
//------------------------------------------------------------*/
//--- Overview of operation ---*/
//------------------------------------------------------------*/
// The size of the stacks and heap is tracked. The heap is tracked in a lot
// of detail, enough to tell how many bytes each line of code is responsible
// for, more or less. The main data structure is an xtree maintaining the
// call tree beneath all the allocation functions like malloc().
// (Alternatively, if --pages-as-heap=yes is specified, memory is tracked at
// the page level, and each page is treated much like a heap block. We use
// "heap" throughout below to cover this case because the concepts are all the
// same.)
//
// "Snapshots" are recordings of the memory usage. There are two basic
// kinds:
// - Normal: these record the current time, total memory size, total heap
// size, heap admin size and stack size.
// - Detailed: these record those things in a normal snapshot, plus a very
// detailed XTree (see below) indicating how the heap is structured.
//
// Snapshots are taken every so often. There are two storage classes of
// snapshots:
// - Temporary: Massif does a temporary snapshot every so often. The idea
// is to always have a certain number of temporary snapshots around. So
// we take them frequently to begin with, but decreasingly often as the
// program continues to run. Also, we remove some old ones after a while.
// Overall it's a kind of exponential decay thing. Most of these are
// normal snapshots, a small fraction are detailed snapshots.
// - Permanent: Massif takes a permanent (detailed) snapshot in some
// circumstances. They are:
// - Peak snapshot: When the memory usage peak is reached, it takes a
// snapshot. It keeps this, unless the peak is subsequently exceeded,
// in which case it will overwrite the peak snapshot.
// - User-requested snapshots: These are done in response to client
// requests. They are always kept.
// Used for printing things when clo_verbosity > 1.
#define VERB(verb, format, args...) \
if (UNLIKELY(VG_(clo_verbosity) > verb)) { \
VG_(dmsg)("Massif: " format, ##args); \
}
//------------------------------------------------------------//
//--- Statistics ---//
//------------------------------------------------------------//
// Konqueror startup, to give an idea of the numbers involved with a biggish
// program, with default depth:
//
// depth=3 depth=40
// - 310,000 allocations
// - 300,000 frees
// - 15,000 XPts 800,000 XPts
// - 1,800 top-XPts
static UInt n_heap_allocs = 0;
static UInt n_heap_reallocs = 0;
static UInt n_heap_frees = 0;
static UInt n_ignored_heap_allocs = 0;
static UInt n_ignored_heap_frees = 0;
static UInt n_ignored_heap_reallocs = 0;
static UInt n_stack_allocs = 0;
static UInt n_stack_frees = 0;
static UInt n_skipped_snapshots = 0;
static UInt n_real_snapshots = 0;
static UInt n_detailed_snapshots = 0;
static UInt n_peak_snapshots = 0;
static UInt n_cullings = 0;
//------------------------------------------------------------//
//--- Globals ---//
//------------------------------------------------------------//
// Number of guest instructions executed so far. Only used with
// --time-unit=i.
static Long guest_instrs_executed = 0;
static SizeT heap_szB = 0; // Live heap size
static SizeT heap_extra_szB = 0; // Live heap extra size -- slop + admin bytes
static SizeT stacks_szB = 0; // Live stacks size
// This is the total size from the current peak snapshot, or 0 if no peak
// snapshot has been taken yet.
static SizeT peak_snapshot_total_szB = 0;
// Incremented every time memory is allocated/deallocated, by the
// allocated/deallocated amount; includes heap, heap-admin and stack
// memory. An alternative to milliseconds as a unit of program "time".
static ULong total_allocs_deallocs_szB = 0;
// When running with --heap=yes --pages-as-heap=no, we don't start taking
// snapshots until the first basic block is executed, rather than doing it in
// ms_post_clo_init (which is the obvious spot), for two reasons.
// - It lets us ignore stack events prior to that, because they're not
// really proper ones and just would screw things up.
// - Because there's still some core initialisation to do, and so there
// would be an artificial time gap between the first and second snapshots.
//
// When running with --heap=yes --pages-as-heap=yes, snapshots start much
// earlier due to new_mem_startup so this isn't relevant.
//
static Bool have_started_executing_code = False;
//------------------------------------------------------------//
//--- Alloc fns ---//
//------------------------------------------------------------//
static XArray* alloc_fns;
static XArray* ignore_fns;
static void init_alloc_fns(void)
{
// Create the list, and add the default elements.
alloc_fns = VG_(newXA)(VG_(malloc), "ms.main.iaf.1",
VG_(free), sizeof(HChar*));
#define DO(x) { const HChar* s = x; VG_(addToXA)(alloc_fns, &s); }
// Ordered roughly according to (presumed) frequency.
// Nb: The C++ "operator new*" ones are overloadable. We include them
// always anyway, because even if they're overloaded, it would be a
// prodigiously stupid overloading that caused them to not allocate
// memory.
//
// XXX: because we don't look at the first stack entry (unless it's a
// custom allocation) there's not much point to having all these alloc
// functions here -- they should never appear anywhere (I think?) other
// than the top stack entry. The only exceptions are those that in
// vg_replace_malloc.c are partly or fully implemented in terms of another
// alloc function: realloc (which uses malloc); valloc,
// malloc_zone_valloc, posix_memalign and memalign_common (which use
// memalign).
//
DO("malloc" );
DO("__builtin_new" );
DO("operator new(unsigned)" );
DO("operator new(unsigned long)" );
DO("__builtin_vec_new" );
DO("operator new[](unsigned)" );
DO("operator new[](unsigned long)" );
DO("calloc" );
DO("realloc" );
DO("memalign" );
DO("posix_memalign" );
DO("valloc" );
DO("operator new(unsigned, std::nothrow_t const&)" );
DO("operator new[](unsigned, std::nothrow_t const&)" );
DO("operator new(unsigned long, std::nothrow_t const&)" );
DO("operator new[](unsigned long, std::nothrow_t const&)");
#if defined(VGO_darwin)
DO("malloc_zone_malloc" );
DO("malloc_zone_calloc" );
DO("malloc_zone_realloc" );
DO("malloc_zone_memalign" );
DO("malloc_zone_valloc" );
#endif
}
static void init_ignore_fns(void)
{
// Create the (empty) list.
ignore_fns = VG_(newXA)(VG_(malloc), "ms.main.iif.1",
VG_(free), sizeof(HChar*));
}
//------------------------------------------------------------//
//--- Command line args ---//
//------------------------------------------------------------//
#define MAX_DEPTH 200
typedef enum { TimeI, TimeMS, TimeB } TimeUnit;
static const HChar* TimeUnit_to_string(TimeUnit time_unit)
{
switch (time_unit) {
case TimeI: return "i";
case TimeMS: return "ms";
case TimeB: return "B";
default: tl_assert2(0, "TimeUnit_to_string: unrecognised TimeUnit");
}
}
static Bool clo_heap = True;
// clo_heap_admin is deliberately a word-sized type. At one point it was
// a UInt, but this caused problems on 64-bit machines when it was
// multiplied by a small negative number and then promoted to a
// word-sized type -- it ended up with a value of 4.2 billion. Sigh.
static SSizeT clo_heap_admin = 8;
static Bool clo_pages_as_heap = False;
static Bool clo_stacks = False;
static Int clo_depth = 30;
static double clo_threshold = 1.0; // percentage
static double clo_peak_inaccuracy = 1.0; // percentage
static Int clo_time_unit = TimeI;
static Int clo_detailed_freq = 10;
static Int clo_max_snapshots = 100;
static const HChar* clo_massif_out_file = "massif.out.%p";
static XArray* args_for_massif;
static Bool ms_process_cmd_line_option(const HChar* arg)
{
const HChar* tmp_str;
// Remember the arg for later use.
VG_(addToXA)(args_for_massif, &arg);
if VG_BOOL_CLO(arg, "--heap", clo_heap) {}
else if VG_BINT_CLO(arg, "--heap-admin", clo_heap_admin, 0, 1024) {}
else if VG_BOOL_CLO(arg, "--stacks", clo_stacks) {}
else if VG_BOOL_CLO(arg, "--pages-as-heap", clo_pages_as_heap) {}
else if VG_BINT_CLO(arg, "--depth", clo_depth, 1, MAX_DEPTH) {}
else if VG_STR_CLO(arg, "--alloc-fn", tmp_str) {
VG_(addToXA)(alloc_fns, &tmp_str);
}
else if VG_STR_CLO(arg, "--ignore-fn", tmp_str) {
VG_(addToXA)(ignore_fns, &tmp_str);
}
else if VG_DBL_CLO(arg, "--threshold", clo_threshold) {
if (clo_threshold < 0 || clo_threshold > 100) {
VG_(fmsg_bad_option)(arg,
"--threshold must be between 0.0 and 100.0\n");
}
}
else if VG_DBL_CLO(arg, "--peak-inaccuracy", clo_peak_inaccuracy) {}
else if VG_XACT_CLO(arg, "--time-unit=i", clo_time_unit, TimeI) {}
else if VG_XACT_CLO(arg, "--time-unit=ms", clo_time_unit, TimeMS) {}
else if VG_XACT_CLO(arg, "--time-unit=B", clo_time_unit, TimeB) {}
else if VG_BINT_CLO(arg, "--detailed-freq", clo_detailed_freq, 1, 1000000) {}
else if VG_BINT_CLO(arg, "--max-snapshots", clo_max_snapshots, 10, 1000) {}
else if VG_STR_CLO(arg, "--massif-out-file", clo_massif_out_file) {}
else
return VG_(replacement_malloc_process_cmd_line_option)(arg);
return True;
}
static void ms_print_usage(void)
{
VG_(printf)(
" --heap=no|yes profile heap blocks [yes]\n"
" --heap-admin=<size> average admin bytes per heap block;\n"
" ignored if --heap=no [8]\n"
" --stacks=no|yes profile stack(s) [no]\n"
" --pages-as-heap=no|yes profile memory at the page level [no]\n"
" --depth=<number> depth of contexts [30]\n"
" --alloc-fn=<name> specify <name> as an alloc function [empty]\n"
" --ignore-fn=<name> ignore heap allocations within <name> [empty]\n"
" --threshold=<m.n> significance threshold, as a percentage [1.0]\n"
" --peak-inaccuracy=<m.n> maximum peak inaccuracy, as a percentage [1.0]\n"
" --time-unit=i|ms|B time unit: instructions executed, milliseconds\n"
" or heap bytes alloc'd/dealloc'd [i]\n"
" --detailed-freq=<N> every Nth snapshot should be detailed [10]\n"
" --max-snapshots=<N> maximum number of snapshots recorded [100]\n"
" --massif-out-file=<file> output file name [massif.out.%%p]\n"
);
}
static void ms_print_debug_usage(void)
{
VG_(printf)(
" (none)\n"
);
}
//------------------------------------------------------------//
//--- XTrees ---//
//------------------------------------------------------------//
// The details of the heap are represented by a single XTree.
// This XTree maintains the nr of allocated bytes for each
// stacktrace/execontext.
//
// The root of the Xtree will be output as a top node 'alloc functions',
// which represents all allocation functions, eg:
// - malloc/calloc/realloc/memalign/new/new[];
// - user-specified allocation functions (using --alloc-fn);
// - custom allocation (MALLOCLIKE) points
static XTree* heap_xt;
/* heap_xt contains a SizeT: the nr of allocated bytes by this execontext. */
static void init_szB(void* value)
{
*((SizeT*)value) = 0;
}
static void add_szB(void* to, const void* value)
{
*((SizeT*)to) += *((const SizeT*)value);
}
static void sub_szB(void* from, const void* value)
{
*((SizeT*)from) -= *((const SizeT*)value);
}
static ULong alloc_szB(const void* value)
{
return (ULong)*((const SizeT*)value);
}
//------------------------------------------------------------//
//--- XTree Operations ---//
//------------------------------------------------------------//
// This is the limit on the number of filtered alloc-fns that can be in a
// single stacktrace.
#define MAX_OVERESTIMATE 50
#define MAX_IPS (MAX_DEPTH + MAX_OVERESTIMATE)
// filtering out uninteresting entries:
// alloc-fns and entries above alloc-fns, and entries below main-or-below-main.
// Eg: alloc-fn1 / alloc-fn2 / a / b / main / (below main) / c
// becomes: a / b / main
// Nb: it's possible to end up with an empty trace, eg. if 'main' is marked
// as an alloc-fn. This is ok.
static
void filter_IPs (Addr* ips, Int n_ips,
UInt* top, UInt* n_ips_sel)
{
Int i;
Bool top_has_fnname;
const HChar *fnname;
*top = 0;
*n_ips_sel = n_ips;
// Advance *top as long as we find alloc functions
// PW Nov 2016 xtree work:
// old massif code was doing something really strange(?buggy):
// 'sliding' a bunch of functions without names by removing an
// alloc function 'inside' a stacktrace e.g.
// 0x1 0x2 0x3 alloc func1 main
// becomes 0x1 0x2 0x3 func1 main
for (i = *top; i < n_ips; i++) {
top_has_fnname = VG_(get_fnname)(ips[*top], &fnname);
if (top_has_fnname && VG_(strIsMemberXA)(alloc_fns, fnname)) {
VERB(4, "filtering alloc fn %s\n", fnname);
(*top)++;
(*n_ips_sel)--;
} else {
break;
}
}
// filter the whole stacktrace if this allocation has to be ignored.
if (*n_ips_sel > 0
&& top_has_fnname
&& VG_(strIsMemberXA)(ignore_fns, fnname)) {
VERB(4, "ignored allocation from fn %s\n", fnname);
*top = n_ips;
*n_ips_sel = 0;
}
if (!VG_(clo_show_below_main) && *n_ips_sel > 0 ) {
Int mbm = VG_(XT_offset_main_or_below_main)(ips, n_ips);
if (mbm < *top) {
// Special case: the first main (or below main) function is an
// alloc function.
*n_ips_sel = 1;
VERB(4, "main/below main: keeping 1 fn\n");
} else {
*n_ips_sel -= n_ips - mbm - 1;
VERB(4, "main/below main: filtering %d\n", n_ips - mbm - 1);
}
}
// filter the frames if we have more than clo_depth
if (*n_ips_sel > clo_depth) {
VERB(4, "filtering IPs above clo_depth\n");
*n_ips_sel = clo_depth;
}
}
// Capture a stacktrace, and make an ec of it, without the first entry
// if exclude_first_entry is True.
static ExeContext* make_ec(ThreadId tid, Bool exclude_first_entry)
{
static Addr ips[MAX_IPS];
// After this call, the IPs we want are in ips[0]..ips[n_ips-1].
Int n_ips = VG_(get_StackTrace)( tid, ips, clo_depth + MAX_OVERESTIMATE,
NULL/*array to dump SP values in*/,
NULL/*array to dump FP values in*/,
0/*first_ip_delta*/ );
if (exclude_first_entry && n_ips > 0) {
const HChar *fnname;
VERB(4, "removing top fn %s from stacktrace\n",
VG_(get_fnname)(ips[0], &fnname) ? fnname : "???");
return VG_(make_ExeContext_from_StackTrace)(ips+1, n_ips-1);
} else
return VG_(make_ExeContext_from_StackTrace)(ips, n_ips);
}
// Create (or update) in heap_xt an xec corresponding to the stacktrace of tid.
// req_szB is added to the xec (unless ec is fully filtered).
// Returns the correspding XTree xec.
// exclude_first_entry is an optimisation: if True, automatically removes
// the top level IP from the stacktrace. Should be set to True if it is known
// that this is an alloc fn. The top function presumably will be something like
// malloc or __builtin_new that we're sure to filter out).
static Xecu add_heap_xt( ThreadId tid, SizeT req_szB, Bool exclude_first_entry)
{
ExeContext *ec = make_ec(tid, exclude_first_entry);
if (UNLIKELY(VG_(clo_xtree_memory) == Vg_XTMemory_Full))
VG_(XTMemory_Full_alloc)(req_szB, ec);
return VG_(XT_add_to_ec) (heap_xt, ec, &req_szB);
}
// Substract req_szB from the heap_xt where.
static void sub_heap_xt(Xecu where, SizeT req_szB, Bool exclude_first_entry)
{
tl_assert(clo_heap);
if (0 == req_szB)
return;
VG_(XT_sub_from_xecu) (heap_xt, where, &req_szB);
if (UNLIKELY(VG_(clo_xtree_memory) == Vg_XTMemory_Full)) {
ExeContext *ec_free = make_ec(VG_(get_running_tid)(),
exclude_first_entry);
VG_(XTMemory_Full_free)(req_szB,
VG_(XT_get_ec_from_xecu)(heap_xt, where),
ec_free);
}
}
//------------------------------------------------------------//
//--- Snapshots ---//
//------------------------------------------------------------//
// Snapshots are done in a way so that we always have a reasonable number of
// them. We start by taking them quickly. Once we hit our limit, we cull
// some (eg. half), and start taking them more slowly. Once we hit the
// limit again, we again cull and then take them even more slowly, and so
// on.
#define UNUSED_SNAPSHOT_TIME -333 // A conspicuous negative number.
typedef
enum {
Normal = 77,
Peak,
Unused
}
SnapshotKind;
typedef
struct {
SnapshotKind kind;
Time time;
SizeT heap_szB;
SizeT heap_extra_szB;// Heap slop + admin bytes.
SizeT stacks_szB;
XTree* xt; // Snapshot of heap_xt, if a detailed snapshot,
} // otherwise NULL.
Snapshot;
static UInt next_snapshot_i = 0; // Index of where next snapshot will go.
static Snapshot* snapshots; // Array of snapshots.
static Bool is_snapshot_in_use(Snapshot* snapshot)
{
if (Unused == snapshot->kind) {
// If snapshot is unused, check all the fields are unset.
tl_assert(snapshot->time == UNUSED_SNAPSHOT_TIME);
tl_assert(snapshot->heap_extra_szB == 0);
tl_assert(snapshot->heap_szB == 0);
tl_assert(snapshot->stacks_szB == 0);
tl_assert(snapshot->xt == NULL);
return False;
} else {
tl_assert(snapshot->time != UNUSED_SNAPSHOT_TIME);
return True;
}
}
static Bool is_detailed_snapshot(Snapshot* snapshot)
{
return (snapshot->xt ? True : False);
}
static Bool is_uncullable_snapshot(Snapshot* snapshot)
{
return &snapshots[0] == snapshot // First snapshot
|| &snapshots[next_snapshot_i-1] == snapshot // Last snapshot
|| snapshot->kind == Peak; // Peak snapshot
}
static void sanity_check_snapshot(Snapshot* snapshot)
{
// Not much we can sanity check.
tl_assert(snapshot->xt == NULL || snapshot->kind != Unused);
}
// All the used entries should look used, all the unused ones should be clear.
static void sanity_check_snapshots_array(void)
{
Int i;
for (i = 0; i < next_snapshot_i; i++) {
tl_assert( is_snapshot_in_use( & snapshots[i] ));
}
for ( ; i < clo_max_snapshots; i++) {
tl_assert(!is_snapshot_in_use( & snapshots[i] ));
}
}
// This zeroes all the fields in the snapshot, but does not free the xt
// XTree if present. It also does a sanity check unless asked not to; we
// can't sanity check at startup when clearing the initial snapshots because
// they're full of junk.
static void clear_snapshot(Snapshot* snapshot, Bool do_sanity_check)
{
if (do_sanity_check) sanity_check_snapshot(snapshot);
snapshot->kind = Unused;
snapshot->time = UNUSED_SNAPSHOT_TIME;
snapshot->heap_extra_szB = 0;
snapshot->heap_szB = 0;
snapshot->stacks_szB = 0;
snapshot->xt = NULL;
}
// This zeroes all the fields in the snapshot, and frees the heap XTree xt if
// present.
static void delete_snapshot(Snapshot* snapshot)
{
// Nb: if there's an XTree, we free it after calling clear_snapshot,
// because clear_snapshot does a sanity check which includes checking the
// XTree.
XTree* tmp_xt = snapshot->xt;
clear_snapshot(snapshot, /*do_sanity_check*/True);
if (tmp_xt) {
VG_(XT_delete)(tmp_xt);
}
}
static void VERB_snapshot(Int verbosity, const HChar* prefix, Int i)
{
Snapshot* snapshot = &snapshots[i];
const HChar* suffix;
switch (snapshot->kind) {
case Peak: suffix = "p"; break;
case Normal: suffix = ( is_detailed_snapshot(snapshot) ? "d" : "." ); break;
case Unused: suffix = "u"; break;
default:
tl_assert2(0, "VERB_snapshot: unknown snapshot kind: %d", snapshot->kind);
}
VERB(verbosity, "%s S%s%3d (t:%lld, hp:%lu, ex:%lu, st:%lu)\n",
prefix, suffix, i,
snapshot->time,
snapshot->heap_szB,
snapshot->heap_extra_szB,
snapshot->stacks_szB
);
}
// Cull half the snapshots; we choose those that represent the smallest
// time-spans, because that gives us the most even distribution of snapshots
// over time. (It's possible to lose interesting spikes, however.)
//
// Algorithm for N snapshots: We find the snapshot representing the smallest
// timeframe, and remove it. We repeat this until (N/2) snapshots are gone.
// We have to do this one snapshot at a time, rather than finding the (N/2)
// smallest snapshots in one hit, because when a snapshot is removed, its
// neighbours immediately cover greater timespans. So it's O(N^2), but N is
// small, and it's not done very often.
//
// Once we're done, we return the new smallest interval between snapshots.
// That becomes our minimum time interval.
static UInt cull_snapshots(void)
{
Int i, jp, j, jn, min_timespan_i;
Int n_deleted = 0;
Time min_timespan;
n_cullings++;
// Sets j to the index of the first not-yet-removed snapshot at or after i
#define FIND_SNAPSHOT(i, j) \
for (j = i; \
j < clo_max_snapshots && !is_snapshot_in_use(&snapshots[j]); \
j++) { }
VERB(2, "Culling...\n");
// First we remove enough snapshots by clearing them in-place. Once
// that's done, we can slide the remaining ones down.
for (i = 0; i < clo_max_snapshots/2; i++) {
// Find the snapshot representing the smallest timespan. The timespan
// for snapshot n = d(N-1,N)+d(N,N+1), where d(A,B) is the time between
// snapshot A and B. We don't consider the first and last snapshots for
// removal.
Snapshot* min_snapshot;
Int min_j;
// Initial triple: (prev, curr, next) == (jp, j, jn)
// Initial min_timespan is the first one.
jp = 0;
FIND_SNAPSHOT(1, j);
FIND_SNAPSHOT(j+1, jn);
min_timespan = 0x7fffffffffffffffLL;
min_j = -1;
while (jn < clo_max_snapshots) {
Time timespan = snapshots[jn].time - snapshots[jp].time;
tl_assert(timespan >= 0);
// Nb: We never cull the peak snapshot.
if (Peak != snapshots[j].kind && timespan < min_timespan) {
min_timespan = timespan;
min_j = j;
}
// Move on to next triple
jp = j;
j = jn;
FIND_SNAPSHOT(jn+1, jn);
}
// We've found the least important snapshot, now delete it. First
// print it if necessary.
tl_assert(-1 != min_j); // Check we found a minimum.
min_snapshot = & snapshots[ min_j ];
if (VG_(clo_verbosity) > 1) {
HChar buf[64]; // large enough
VG_(snprintf)(buf, 64, " %3d (t-span = %lld)", i, min_timespan);
VERB_snapshot(2, buf, min_j);
}
delete_snapshot(min_snapshot);
n_deleted++;
}
// Slide down the remaining snapshots over the removed ones. First set i
// to point to the first empty slot, and j to the first full slot after
// i. Then slide everything down.
for (i = 0; is_snapshot_in_use( &snapshots[i] ); i++) { }
for (j = i; !is_snapshot_in_use( &snapshots[j] ); j++) { }
for ( ; j < clo_max_snapshots; j++) {
if (is_snapshot_in_use( &snapshots[j] )) {
snapshots[i++] = snapshots[j];
clear_snapshot(&snapshots[j], /*do_sanity_check*/True);
}
}
next_snapshot_i = i;
// Check snapshots array looks ok after changes.
sanity_check_snapshots_array();
// Find the minimum timespan remaining; that will be our new minimum
// time interval. Note that above we were finding timespans by measuring
// two intervals around a snapshot that was under consideration for
// deletion. Here we only measure single intervals because all the
// deletions have occurred.
//
// But we have to be careful -- some snapshots (eg. snapshot 0, and the
// peak snapshot) are uncullable. If two uncullable snapshots end up
// next to each other, they'll never be culled (assuming the peak doesn't
// change), and the time gap between them will not change. However, the
// time between the remaining cullable snapshots will grow ever larger.
// This means that the min_timespan found will always be that between the
// two uncullable snapshots, and it will be much smaller than it should
// be. To avoid this problem, when computing the minimum timespan, we
// ignore any timespans between two uncullable snapshots.
tl_assert(next_snapshot_i > 1);
min_timespan = 0x7fffffffffffffffLL;
min_timespan_i = -1;
for (i = 1; i < next_snapshot_i; i++) {
if (is_uncullable_snapshot(&snapshots[i]) &&
is_uncullable_snapshot(&snapshots[i-1]))
{
VERB(2, "(Ignoring interval %d--%d when computing minimum)\n", i-1, i);
} else {
Time timespan = snapshots[i].time - snapshots[i-1].time;
tl_assert(timespan >= 0);
if (timespan < min_timespan) {
min_timespan = timespan;
min_timespan_i = i;
}
}
}
tl_assert(-1 != min_timespan_i); // Check we found a minimum.
// Print remaining snapshots, if necessary.
if (VG_(clo_verbosity) > 1) {
VERB(2, "Finished culling (%3d of %3d deleted)\n",
n_deleted, clo_max_snapshots);
for (i = 0; i < next_snapshot_i; i++) {
VERB_snapshot(2, " post-cull", i);
}
VERB(2, "New time interval = %lld (between snapshots %d and %d)\n",
min_timespan, min_timespan_i-1, min_timespan_i);
}
return min_timespan;
}
static Time get_time(void)
{
// Get current time, in whatever time unit we're using.
if (clo_time_unit == TimeI) {
return guest_instrs_executed;
} else if (clo_time_unit == TimeMS) {
// Some stuff happens between the millisecond timer being initialised
// to zero and us taking our first snapshot. We determine that time
// gap so we can subtract it from all subsequent times so that our
// first snapshot is considered to be at t = 0ms. Unfortunately, a
// bunch of symbols get read after the first snapshot is taken but
// before the second one (which is triggered by the first allocation),
// so when the time-unit is 'ms' we always have a big gap between the
// first two snapshots. But at least users won't have to wonder why
// the first snapshot isn't at t=0.
static Bool is_first_get_time = True;
static Time start_time_ms;
if (is_first_get_time) {
start_time_ms = VG_(read_millisecond_timer)();
is_first_get_time = False;
return 0;
} else {
return VG_(read_millisecond_timer)() - start_time_ms;
}
} else if (clo_time_unit == TimeB) {
return total_allocs_deallocs_szB;
} else {
tl_assert2(0, "bad --time-unit value");
}
}
// Take a snapshot, and only that -- decisions on whether to take a
// snapshot, or what kind of snapshot, are made elsewhere.
// Nb: we call the arg "my_time" because "time" shadows a global declaration
// in /usr/include/time.h on Darwin.
static void
take_snapshot(Snapshot* snapshot, SnapshotKind kind, Time my_time,
Bool is_detailed)
{
tl_assert(!is_snapshot_in_use(snapshot));
if (!clo_pages_as_heap) {
tl_assert(have_started_executing_code);
}
// Heap and heap admin.
if (clo_heap) {
snapshot->heap_szB = heap_szB;
if (is_detailed) {
snapshot->xt = VG_(XT_snapshot)(heap_xt);
}
snapshot->heap_extra_szB = heap_extra_szB;
}
// Stack(s).
if (clo_stacks) {
snapshot->stacks_szB = stacks_szB;
}
// Rest of snapshot.
snapshot->kind = kind;
snapshot->time = my_time;
sanity_check_snapshot(snapshot);
// Update stats.
if (Peak == kind) n_peak_snapshots++;
if (is_detailed) n_detailed_snapshots++;
n_real_snapshots++;
}
// Take a snapshot, if it's time, or if we've hit a peak.
static void
maybe_take_snapshot(SnapshotKind kind, const HChar* what)
{
// 'min_time_interval' is the minimum time interval between snapshots.
// If we try to take a snapshot and less than this much time has passed,
// we don't take it. It gets larger as the program runs longer. It's
// initialised to zero so that we begin by taking snapshots as quickly as
// possible.
static Time min_time_interval = 0;
// Zero allows startup snapshot.
static Time earliest_possible_time_of_next_snapshot = 0;
static Int n_snapshots_since_last_detailed = 0;
static Int n_skipped_snapshots_since_last_snapshot = 0;
Snapshot* snapshot;
Bool is_detailed;
// Nb: we call this variable "my_time" because "time" shadows a global
// declaration in /usr/include/time.h on Darwin.
Time my_time = get_time();
switch (kind) {
case Normal:
// Only do a snapshot if it's time.
if (my_time < earliest_possible_time_of_next_snapshot) {
n_skipped_snapshots++;
n_skipped_snapshots_since_last_snapshot++;
return;
}
is_detailed = (clo_detailed_freq-1 == n_snapshots_since_last_detailed);
break;
case Peak: {
// Because we're about to do a deallocation, we're coming down from a
// local peak. If it is (a) actually a global peak, and (b) a certain
// amount bigger than the previous peak, then we take a peak snapshot.
// By not taking a snapshot for every peak, we save a lot of effort --
// because many peaks remain peak only for a short time.
SizeT total_szB = heap_szB + heap_extra_szB + stacks_szB;
SizeT excess_szB_for_new_peak =
(SizeT)((peak_snapshot_total_szB * clo_peak_inaccuracy) / 100);
if (total_szB <= peak_snapshot_total_szB + excess_szB_for_new_peak) {
return;
}
is_detailed = True;
break;
}
default:
tl_assert2(0, "maybe_take_snapshot: unrecognised snapshot kind");
}
// Take the snapshot.
snapshot = & snapshots[next_snapshot_i];
take_snapshot(snapshot, kind, my_time, is_detailed);
// Record if it was detailed.
if (is_detailed) {
n_snapshots_since_last_detailed = 0;
} else {
n_snapshots_since_last_detailed++;
}
// Update peak data, if it's a Peak snapshot.
if (Peak == kind) {
Int i, number_of_peaks_snapshots_found = 0;
// Sanity check the size, then update our recorded peak.
SizeT snapshot_total_szB =
snapshot->heap_szB + snapshot->heap_extra_szB + snapshot->stacks_szB;
tl_assert2(snapshot_total_szB > peak_snapshot_total_szB,
"%ld, %ld\n", snapshot_total_szB, peak_snapshot_total_szB);
peak_snapshot_total_szB = snapshot_total_szB;
// Find the old peak snapshot, if it exists, and mark it as normal.
for (i = 0; i < next_snapshot_i; i++) {
if (Peak == snapshots[i].kind) {
snapshots[i].kind = Normal;
number_of_peaks_snapshots_found++;
}
}
tl_assert(number_of_peaks_snapshots_found <= 1);
}
// Finish up verbosity and stats stuff.
if (n_skipped_snapshots_since_last_snapshot > 0) {
VERB(2, " (skipped %d snapshot%s)\n",
n_skipped_snapshots_since_last_snapshot,
( 1 == n_skipped_snapshots_since_last_snapshot ? "" : "s") );
}
VERB_snapshot(2, what, next_snapshot_i);
n_skipped_snapshots_since_last_snapshot = 0;
// Cull the entries, if our snapshot table is full.
next_snapshot_i++;
if (clo_max_snapshots == next_snapshot_i) {
min_time_interval = cull_snapshots();
}
// Work out the earliest time when the next snapshot can happen.
earliest_possible_time_of_next_snapshot = my_time + min_time_interval;
}
//------------------------------------------------------------//
//--- Sanity checking ---//
//------------------------------------------------------------//
static Bool ms_cheap_sanity_check ( void )
{
return True; // Nothing useful we can cheaply check.
}
static Bool ms_expensive_sanity_check ( void )
{
tl_assert(heap_xt);
sanity_check_snapshots_array();
return True;
}
//------------------------------------------------------------//
//--- Heap management ---//
//------------------------------------------------------------//
// Metadata for heap blocks. Each one contains an Xecu,
// which identifies the XTree ec at which it was allocated. From
// HP_Chunks, XTree ec 'space' field is incremented (at allocation) and
// decremented (at deallocation).
//
// Nb: first two fields must match core's VgHashNode.
typedef
struct _HP_Chunk {
struct _HP_Chunk* next;
Addr data; // Ptr to actual block
SizeT req_szB; // Size requested
SizeT slop_szB; // Extra bytes given above those requested
Xecu where; // Where allocated; XTree xecu from heap_xt
}
HP_Chunk;
/* Pool allocator for HP_Chunk. */
static PoolAlloc *HP_chunk_poolalloc = NULL;
static VgHashTable *malloc_list = NULL; // HP_Chunks
static void update_alloc_stats(SSizeT szB_delta)
{
// Update total_allocs_deallocs_szB.
if (szB_delta < 0) szB_delta = -szB_delta;
total_allocs_deallocs_szB += szB_delta;
}
static void update_heap_stats(SSizeT heap_szB_delta, Int heap_extra_szB_delta)
{
if (heap_szB_delta < 0)
tl_assert(heap_szB >= -heap_szB_delta);
if (heap_extra_szB_delta < 0)
tl_assert(heap_extra_szB >= -heap_extra_szB_delta);
heap_extra_szB += heap_extra_szB_delta;
heap_szB += heap_szB_delta;
update_alloc_stats(heap_szB_delta + heap_extra_szB_delta);
}
static
void* record_block( ThreadId tid, void* p, SizeT req_szB, SizeT slop_szB,
Bool exclude_first_entry, Bool maybe_snapshot )
{
// Make new HP_Chunk node, add to malloc_list
HP_Chunk* hc = VG_(allocEltPA)(HP_chunk_poolalloc);
hc->req_szB = req_szB;
hc->slop_szB = slop_szB;
hc->data = (Addr)p;
hc->where = 0;
VG_(HT_add_node)(malloc_list, hc);
if (clo_heap) {
VERB(3, "<<< record_block (%lu, %lu)\n", req_szB, slop_szB);
hc->where = add_heap_xt( tid, req_szB, exclude_first_entry);
if (VG_(XT_n_ips_sel)(heap_xt, hc->where) > 0) {
// Update statistics.
n_heap_allocs++;
// Update heap stats.
update_heap_stats(req_szB, clo_heap_admin + slop_szB);
// Maybe take a snapshot.
if (maybe_snapshot) {
maybe_take_snapshot(Normal, " alloc");
}
} else {
// Ignored allocation.
n_ignored_heap_allocs++;
VERB(3, "(ignored)\n");
}
VERB(3, ">>>\n");
}
return p;
}
static __inline__
void* alloc_and_record_block ( ThreadId tid, SizeT req_szB, SizeT req_alignB,
Bool is_zeroed )
{
SizeT actual_szB, slop_szB;
void* p;
if ((SSizeT)req_szB < 0) return NULL;
// Allocate and zero if necessary.
p = VG_(cli_malloc)( req_alignB, req_szB );
if (!p) {
return NULL;
}
if (is_zeroed) VG_(memset)(p, 0, req_szB);
actual_szB = VG_(cli_malloc_usable_size)(p);
tl_assert(actual_szB >= req_szB);
slop_szB = actual_szB - req_szB;
// Record block.
record_block(tid, p, req_szB, slop_szB, /*exclude_first_entry*/True,
/*maybe_snapshot*/True);
return p;
}
static __inline__
void unrecord_block ( void* p, Bool maybe_snapshot, Bool exclude_first_entry )
{
// Remove HP_Chunk from malloc_list
HP_Chunk* hc = VG_(HT_remove)(malloc_list, (UWord)p);
if (NULL == hc) {
return; // must have been a bogus free()
}
if (clo_heap) {
VERB(3, "<<< unrecord_block\n");
if (VG_(XT_n_ips_sel)(heap_xt, hc->where) > 0) {
// Update statistics.
n_heap_frees++;
// Maybe take a peak snapshot, since it's a deallocation.
if (maybe_snapshot) {
maybe_take_snapshot(Peak, "de-PEAK");
}
// Update heap stats.
update_heap_stats(-hc->req_szB, -clo_heap_admin - hc->slop_szB);
// Update XTree.
sub_heap_xt(hc->where, hc->req_szB, exclude_first_entry);
// Maybe take a snapshot.
if (maybe_snapshot) {
maybe_take_snapshot(Normal, "dealloc");
}
} else {
n_ignored_heap_frees++;
VERB(3, "(ignored)\n");
}
VERB(3, ">>> (-%lu, -%lu)\n", hc->req_szB, hc->slop_szB);
}
// Actually free the chunk, and the heap block (if necessary)
VG_(freeEltPA) (HP_chunk_poolalloc, hc); hc = NULL;
}
// Nb: --ignore-fn is tricky for realloc. If the block's original alloc was
// ignored, but the realloc is not requested to be ignored, and we are
// shrinking the block, then we have to ignore the realloc -- otherwise we
// could end up with negative heap sizes. This isn't a danger if we are
// growing such a block, but for consistency (it also simplifies things) we
// ignore such reallocs as well.
// PW Nov 2016 xtree work: why can't we just consider that a realloc of an
// ignored alloc is just a new alloc (i.e. do not remove the old sz from the
// stats). Then everything would be fine, and a non ignored realloc would be
// counted properly.
static __inline__
void* realloc_block ( ThreadId tid, void* p_old, SizeT new_req_szB )
{
HP_Chunk* hc;
void* p_new;
SizeT old_req_szB, old_slop_szB, new_slop_szB, new_actual_szB;
Xecu old_where;
Bool is_ignored = False;
// Remove the old block
hc = VG_(HT_remove)(malloc_list, (UWord)p_old);
if (hc == NULL) {
return NULL; // must have been a bogus realloc()
}
old_req_szB = hc->req_szB;
old_slop_szB = hc->slop_szB;
tl_assert(!clo_pages_as_heap); // Shouldn't be here if --pages-as-heap=yes.
if (clo_heap) {
VERB(3, "<<< realloc_block (%lu)\n", new_req_szB);
if (VG_(XT_n_ips_sel)(heap_xt, hc->where) > 0) {
// Update statistics.
n_heap_reallocs++;
// Maybe take a peak snapshot, if it's (effectively) a deallocation.
if (new_req_szB < old_req_szB) {
maybe_take_snapshot(Peak, "re-PEAK");
}
} else {
// The original malloc was ignored, so we have to ignore the
// realloc as well.
is_ignored = True;
}
}
// Actually do the allocation, if necessary.
if (new_req_szB <= old_req_szB + old_slop_szB) {
// New size is smaller or same; block not moved.
p_new = p_old;
new_slop_szB = old_slop_szB + (old_req_szB - new_req_szB);
} else {
// New size is bigger; make new block, copy shared contents, free old.
p_new = VG_(cli_malloc)(VG_(clo_alignment), new_req_szB);
if (!p_new) {
// Nb: if realloc fails, NULL is returned but the old block is not
// touched. What an awful function.
return NULL;
}
VG_(memcpy)(p_new, p_old, old_req_szB + old_slop_szB);
VG_(cli_free)(p_old);
new_actual_szB = VG_(cli_malloc_usable_size)(p_new);
tl_assert(new_actual_szB >= new_req_szB);
new_slop_szB = new_actual_szB - new_req_szB;
}
if (p_new) {
// Update HP_Chunk.
hc->data = (Addr)p_new;
hc->req_szB = new_req_szB;
hc->slop_szB = new_slop_szB;
old_where = hc->where;
hc->where = 0;
// Update XTree.
if (clo_heap) {
hc->where = add_heap_xt( tid, new_req_szB,
/*exclude_first_entry*/True);
if (!is_ignored && VG_(XT_n_ips_sel)(heap_xt, hc->where) > 0) {
sub_heap_xt(old_where, old_req_szB, /*exclude_first_entry*/True);
} else {
// The realloc itself is ignored.
is_ignored = True;
/* XTREE??? hack to have something compatible with pre
m_xtree massif: if the previous alloc/realloc was
ignored, and this one is not ignored, then keep the
previous where, to continue marking this memory as
ignored. */
if (VG_(XT_n_ips_sel)(heap_xt, hc->where) > 0
&& VG_(XT_n_ips_sel)(heap_xt, old_where) == 0)
hc->where = old_where;
// Update statistics.
n_ignored_heap_reallocs++;
}
}
}
// Now insert the new hc (with a possibly new 'data' field) into
// malloc_list. If this realloc() did not increase the memory size, we
// will have removed and then re-added hc unnecessarily. But that's ok
// because shrinking a block with realloc() is (presumably) much rarer
// than growing it, and this way simplifies the growing case.
VG_(HT_add_node)(malloc_list, hc);
if (clo_heap) {
if (!is_ignored) {
// Update heap stats.
update_heap_stats(new_req_szB - old_req_szB,
new_slop_szB - old_slop_szB);
// Maybe take a snapshot.
maybe_take_snapshot(Normal, "realloc");
} else {
VERB(3, "(ignored)\n");
}
VERB(3, ">>> (%ld, %ld)\n",
(SSizeT)(new_req_szB - old_req_szB),
(SSizeT)(new_slop_szB - old_slop_szB));
}
return p_new;
}
//------------------------------------------------------------//
//--- malloc() et al replacement wrappers ---//
//------------------------------------------------------------//
static void* ms_malloc ( ThreadId tid, SizeT szB )
{
return alloc_and_record_block( tid, szB, VG_(clo_alignment), /*is_zeroed*/False );
}
static void* ms___builtin_new ( ThreadId tid, SizeT szB )
{
return alloc_and_record_block( tid, szB, VG_(clo_alignment), /*is_zeroed*/False );
}
static void* ms___builtin_vec_new ( ThreadId tid, SizeT szB )
{
return alloc_and_record_block( tid, szB, VG_(clo_alignment), /*is_zeroed*/False );
}
static void* ms_calloc ( ThreadId tid, SizeT m, SizeT szB )
{
return alloc_and_record_block( tid, m*szB, VG_(clo_alignment), /*is_zeroed*/True );
}
static void *ms_memalign ( ThreadId tid, SizeT alignB, SizeT szB )
{
return alloc_and_record_block( tid, szB, alignB, False );
}
static void ms_free ( ThreadId tid __attribute__((unused)), void* p )
{
unrecord_block(p, /*maybe_snapshot*/True, /*exclude_first_entry*/True);
VG_(cli_free)(p);
}
static void ms___builtin_delete ( ThreadId tid, void* p )
{
unrecord_block(p, /*maybe_snapshot*/True, /*exclude_first_entry*/True);
VG_(cli_free)(p);
}
static void ms___builtin_vec_delete ( ThreadId tid, void* p )
{
unrecord_block(p, /*maybe_snapshot*/True, /*exclude_first_entry*/True);
VG_(cli_free)(p);
}
static void* ms_realloc ( ThreadId tid, void* p_old, SizeT new_szB )
{
return realloc_block(tid, p_old, new_szB);
}
static SizeT ms_malloc_usable_size ( ThreadId tid, void* p )
{
HP_Chunk* hc = VG_(HT_lookup)( malloc_list, (UWord)p );
return ( hc ? hc->req_szB + hc->slop_szB : 0 );
}
//------------------------------------------------------------//
//--- Page handling ---//
//------------------------------------------------------------//
static
void ms_record_page_mem ( Addr a, SizeT len )
{
ThreadId tid = VG_(get_running_tid)();
Addr end;
tl_assert(VG_IS_PAGE_ALIGNED(len));
tl_assert(len >= VKI_PAGE_SIZE);
// Record the first N-1 pages as blocks, but don't do any snapshots.
for (end = a + len - VKI_PAGE_SIZE; a < end; a += VKI_PAGE_SIZE) {
record_block( tid, (void*)a, VKI_PAGE_SIZE, /*slop_szB*/0,
/*exclude_first_entry*/False, /*maybe_snapshot*/False );
}
// Record the last page as a block, and maybe do a snapshot afterwards.
record_block( tid, (void*)a, VKI_PAGE_SIZE, /*slop_szB*/0,
/*exclude_first_entry*/False, /*maybe_snapshot*/True );
}
static
void ms_unrecord_page_mem( Addr a, SizeT len )
{
Addr end;
tl_assert(VG_IS_PAGE_ALIGNED(len));
tl_assert(len >= VKI_PAGE_SIZE);
// Unrecord the first page. This might be the peak, so do a snapshot.
unrecord_block((void*)a, /*maybe_snapshot*/True,
/*exclude_first_entry*/False);
a += VKI_PAGE_SIZE;
// Then unrecord the remaining pages, but without snapshots.
for (end = a + len - VKI_PAGE_SIZE; a < end; a += VKI_PAGE_SIZE) {
unrecord_block((void*)a, /*maybe_snapshot*/False,
/*exclude_first_entry*/False);
}
}
//------------------------------------------------------------//
static
void ms_new_mem_mmap ( Addr a, SizeT len,
Bool rr, Bool ww, Bool xx, ULong di_handle )
{
tl_assert(VG_IS_PAGE_ALIGNED(len));
ms_record_page_mem(a, len);
}
static
void ms_new_mem_startup( Addr a, SizeT len,
Bool rr, Bool ww, Bool xx, ULong di_handle )
{
// startup maps are always be page-sized, except the trampoline page is
// marked by the core as only being the size of the trampoline itself,
// which is something like 57 bytes. Round it up to page size.
len = VG_PGROUNDUP(len);
ms_record_page_mem(a, len);
}
static
void ms_new_mem_brk ( Addr a, SizeT len, ThreadId tid )
{
// brk limit is not necessarily aligned on a page boundary.
// If new memory being brk-ed implies to allocate a new page,
// then call ms_record_page_mem with page aligned parameters
// otherwise just ignore.
Addr old_bottom_page = VG_PGROUNDDN(a - 1);
Addr new_top_page = VG_PGROUNDDN(a + len - 1);
if (old_bottom_page != new_top_page)
ms_record_page_mem(VG_PGROUNDDN(a),
(new_top_page - old_bottom_page));
}
static
void ms_copy_mem_remap( Addr from, Addr to, SizeT len)
{
tl_assert(VG_IS_PAGE_ALIGNED(len));
ms_unrecord_page_mem(from, len);
ms_record_page_mem(to, len);
}
static
void ms_die_mem_munmap( Addr a, SizeT len )
{
tl_assert(VG_IS_PAGE_ALIGNED(len));
ms_unrecord_page_mem(a, len);
}
static
void ms_die_mem_brk( Addr a, SizeT len )
{
// Call ms_unrecord_page_mem only if one or more pages are de-allocated.
// See ms_new_mem_brk for more details.
Addr new_bottom_page = VG_PGROUNDDN(a - 1);
Addr old_top_page = VG_PGROUNDDN(a + len - 1);
if (old_top_page != new_bottom_page)
ms_unrecord_page_mem(VG_PGROUNDDN(a),
(old_top_page - new_bottom_page));
}
//------------------------------------------------------------//
//--- Stacks ---//
//------------------------------------------------------------//
// We really want the inlining to occur...
#define INLINE inline __attribute__((always_inline))
static void update_stack_stats(SSizeT stack_szB_delta)
{
if (stack_szB_delta < 0) tl_assert(stacks_szB >= -stack_szB_delta);
stacks_szB += stack_szB_delta;
update_alloc_stats(stack_szB_delta);
}
static INLINE void new_mem_stack_2(SizeT len, const HChar* what)
{
if (have_started_executing_code) {
VERB(3, "<<< new_mem_stack (%lu)\n", len);
n_stack_allocs++;
update_stack_stats(len);
maybe_take_snapshot(Normal, what);
VERB(3, ">>>\n");
}
}
static INLINE void die_mem_stack_2(SizeT len, const HChar* what)
{
if (have_started_executing_code) {
VERB(3, "<<< die_mem_stack (-%lu)\n", len);
n_stack_frees++;
maybe_take_snapshot(Peak, "stkPEAK");
update_stack_stats(-len);
maybe_take_snapshot(Normal, what);
VERB(3, ">>>\n");
}
}
static void new_mem_stack(Addr a, SizeT len)
{
new_mem_stack_2(len, "stk-new");
}
static void die_mem_stack(Addr a, SizeT len)
{
die_mem_stack_2(len, "stk-die");
}
static void new_mem_stack_signal(Addr a, SizeT len, ThreadId tid)
{
new_mem_stack_2(len, "sig-new");
}
static void die_mem_stack_signal(Addr a, SizeT len)
{
die_mem_stack_2(len, "sig-die");
}
//------------------------------------------------------------//
//--- Client Requests ---//
//------------------------------------------------------------//
static void print_monitor_help ( void )
{
VG_(gdb_printf) (
"\n"
"massif monitor commands:\n"
" snapshot [<filename>]\n"
" detailed_snapshot [<filename>]\n"
" takes a snapshot (or a detailed snapshot)\n"
" and saves it in <filename>\n"
" default <filename> is massif.vgdb.out\n"
" all_snapshots [<filename>]\n"
" saves all snapshot(s) taken so far in <filename>\n"
" default <filename> is massif.vgdb.out\n"
" xtmemory [<filename>]\n"
" dump xtree memory profile in <filename> (default xtmemory.kcg)\n"
"\n");
}
/* Forward declaration.
return True if request recognised, False otherwise */
static Bool handle_gdb_monitor_command (ThreadId tid, HChar *req);
static Bool ms_handle_client_request ( ThreadId tid, UWord* argv, UWord* ret )
{
switch (argv[0]) {
case VG_USERREQ__MALLOCLIKE_BLOCK: {
void* p = (void*)argv[1];
SizeT szB = argv[2];
record_block( tid, p, szB, /*slop_szB*/0, /*exclude_first_entry*/False,
/*maybe_snapshot*/True );
*ret = 0;
return True;
}
case VG_USERREQ__RESIZEINPLACE_BLOCK: {
void* p = (void*)argv[1];
SizeT newSizeB = argv[3];
unrecord_block(p, /*maybe_snapshot*/True, /*exclude_first_entry*/False);
record_block(tid, p, newSizeB, /*slop_szB*/0,
/*exclude_first_entry*/False, /*maybe_snapshot*/True);
return True;
}
case VG_USERREQ__FREELIKE_BLOCK: {
void* p = (void*)argv[1];
unrecord_block(p, /*maybe_snapshot*/True, /*exclude_first_entry*/False);
*ret = 0;
return True;
}
case VG_USERREQ__GDB_MONITOR_COMMAND: {
Bool handled = handle_gdb_monitor_command (tid, (HChar*)argv[1]);
if (handled)
*ret = 1;
else
*ret = 0;
return handled;
}
default:
*ret = 0;
return False;
}
}
//------------------------------------------------------------//
//--- Instrumentation ---//
//------------------------------------------------------------//
static void add_counter_update(IRSB* sbOut, Int n)
{
#if defined(VG_BIGENDIAN)
# define END Iend_BE
#elif defined(VG_LITTLEENDIAN)
# define END Iend_LE
#else
# error "Unknown endianness"
#endif
// Add code to increment 'guest_instrs_executed' by 'n', like this:
// WrTmp(t1, Load64(&guest_instrs_executed))
// WrTmp(t2, Add64(RdTmp(t1), Const(n)))
// Store(&guest_instrs_executed, t2)
IRTemp t1 = newIRTemp(sbOut->tyenv, Ity_I64);
IRTemp t2 = newIRTemp(sbOut->tyenv, Ity_I64);
IRExpr* counter_addr = mkIRExpr_HWord( (HWord)&guest_instrs_executed );
IRStmt* st1 = IRStmt_WrTmp(t1, IRExpr_Load(END, Ity_I64, counter_addr));
IRStmt* st2 =
IRStmt_WrTmp(t2,
IRExpr_Binop(Iop_Add64, IRExpr_RdTmp(t1),
IRExpr_Const(IRConst_U64(n))));
IRStmt* st3 = IRStmt_Store(END, counter_addr, IRExpr_RdTmp(t2));
addStmtToIRSB( sbOut, st1 );
addStmtToIRSB( sbOut, st2 );
addStmtToIRSB( sbOut, st3 );
}
static IRSB* ms_instrument2( IRSB* sbIn )
{
Int i, n = 0;
IRSB* sbOut;
// We increment the instruction count in two places:
// - just before any Ist_Exit statements;
// - just before the IRSB's end.
// In the former case, we zero 'n' and then continue instrumenting.
sbOut = deepCopyIRSBExceptStmts(sbIn);
for (i = 0; i < sbIn->stmts_used; i++) {
IRStmt* st = sbIn->stmts[i];
if (!st || st->tag == Ist_NoOp) continue;
if (st->tag == Ist_IMark) {
n++;
} else if (st->tag == Ist_Exit) {
if (n > 0) {
// Add an increment before the Exit statement, then reset 'n'.
add_counter_update(sbOut, n);
n = 0;
}
}
addStmtToIRSB( sbOut, st );
}
if (n > 0) {
// Add an increment before the SB end.
add_counter_update(sbOut, n);
}
return sbOut;
}
static
IRSB* ms_instrument ( VgCallbackClosure* closure,
IRSB* sbIn,
const VexGuestLayout* layout,
const VexGuestExtents* vge,
const VexArchInfo* archinfo_host,
IRType gWordTy, IRType hWordTy )
{
if (! have_started_executing_code) {
// Do an initial sample to guarantee that we have at least one.
// We use 'maybe_take_snapshot' instead of 'take_snapshot' to ensure
// 'maybe_take_snapshot's internal static variables are initialised.
have_started_executing_code = True;
maybe_take_snapshot(Normal, "startup");
}
if (clo_time_unit == TimeI) { return ms_instrument2(sbIn); }
else if (clo_time_unit == TimeMS) { return sbIn; }
else if (clo_time_unit == TimeB) { return sbIn; }
else { tl_assert2(0, "bad --time-unit value"); }
}
//------------------------------------------------------------//
//--- Writing snapshots ---//
//------------------------------------------------------------//
static void pp_snapshot(MsFile *fp, Snapshot* snapshot, Int snapshot_n)
{
const Massif_Header header = (Massif_Header) {
.snapshot_n = snapshot_n,
.time = snapshot->time,
.sz_B = snapshot->heap_szB,
.extra_B = snapshot->heap_extra_szB,
.stacks_B = snapshot->stacks_szB,
.detailed = is_detailed_snapshot(snapshot),
.peak = Peak == snapshot->kind,
.top_node_desc = clo_pages_as_heap ?
"(page allocation syscalls) mmap/mremap/brk, --alloc-fns, etc."
: "(heap allocation functions) malloc/new/new[], --alloc-fns, etc.",
.sig_threshold = clo_threshold
};
sanity_check_snapshot(snapshot);
VG_(XT_massif_print)(fp, snapshot->xt, &header, alloc_szB);
}
static void write_snapshots_to_file(const HChar* massif_out_file,
Snapshot snapshots_array[],
Int nr_elements)
{
Int i;
MsFile *fp;
fp = VG_(XT_massif_open)(massif_out_file,
NULL,
args_for_massif,
TimeUnit_to_string(clo_time_unit));
if (fp == NULL)
return; // Error reported by VG_(XT_massif_open)
for (i = 0; i < nr_elements; i++) {
Snapshot* snapshot = & snapshots_array[i];
pp_snapshot(fp, snapshot, i); // Detailed snapshot!
}
VG_(XT_massif_close) (fp);
}
static void write_snapshots_array_to_file(void)
{
// Setup output filename. Nb: it's important to do this now, ie. as late
// as possible. If we do it at start-up and the program forks and the
// output file format string contains a %p (pid) specifier, both the
// parent and child will incorrectly write to the same file; this
// happened in 3.3.0.
HChar* massif_out_file =
VG_(expand_file_name)("--massif-out-file", clo_massif_out_file);
write_snapshots_to_file (massif_out_file, snapshots, next_snapshot_i);
VG_(free)(massif_out_file);
}
static void handle_snapshot_monitor_command (const HChar *filename,
Bool detailed)
{
Snapshot snapshot;
if (!clo_pages_as_heap && !have_started_executing_code) {
// See comments of variable have_started_executing_code.
VG_(gdb_printf)
("error: cannot take snapshot before execution has started\n");
return;
}
clear_snapshot(&snapshot, /* do_sanity_check */ False);
take_snapshot(&snapshot, Normal, get_time(), detailed);
write_snapshots_to_file ((filename == NULL) ?
"massif.vgdb.out" : filename,
&snapshot,
1);
delete_snapshot(&snapshot);
}
static void handle_all_snapshots_monitor_command (const HChar *filename)
{
if (!clo_pages_as_heap && !have_started_executing_code) {
// See comments of variable have_started_executing_code.
VG_(gdb_printf)
("error: cannot take snapshot before execution has started\n");
return;
}
write_snapshots_to_file ((filename == NULL) ?
"massif.vgdb.out" : filename,
snapshots, next_snapshot_i);
}
static void xtmemory_report_next_block(XT_Allocs* xta, ExeContext** ec_alloc)
{
const HP_Chunk* hc = VG_(HT_Next)(malloc_list);
if (hc) {
xta->nbytes = hc->req_szB;
xta->nblocks = 1;
*ec_alloc = VG_(XT_get_ec_from_xecu)(heap_xt, hc->where);
} else
xta->nblocks = 0;
}
static void ms_xtmemory_report ( const HChar* filename, Bool fini )
{
// Make xtmemory_report_next_block ready to be called.
VG_(HT_ResetIter)(malloc_list);
VG_(XTMemory_report)(filename, fini, xtmemory_report_next_block,
VG_(XT_filter_maybe_below_main));
/* As massif already filters one top function, use as filter
VG_(XT_filter_maybe_below_main). */
}
static Bool handle_gdb_monitor_command (ThreadId tid, HChar *req)
{
HChar* wcmd;
HChar s[VG_(strlen)(req) + 1]; /* copy for strtok_r */
HChar *ssaveptr;
VG_(strcpy) (s, req);
wcmd = VG_(strtok_r) (s, " ", &ssaveptr);
switch (VG_(keyword_id) ("help snapshot detailed_snapshot all_snapshots"
" xtmemory",
wcmd, kwd_report_duplicated_matches)) {
case -2: /* multiple matches */
return True;
case -1: /* not found */
return False;
case 0: /* help */
print_monitor_help();
return True;
case 1: { /* snapshot */
HChar* filename;
filename = VG_(strtok_r) (NULL, " ", &ssaveptr);
handle_snapshot_monitor_command (filename, False /* detailed */);
return True;
}
case 2: { /* detailed_snapshot */
HChar* filename;
filename = VG_(strtok_r) (NULL, " ", &ssaveptr);
handle_snapshot_monitor_command (filename, True /* detailed */);
return True;
}
case 3: { /* all_snapshots */
HChar* filename;
filename = VG_(strtok_r) (NULL, " ", &ssaveptr);
handle_all_snapshots_monitor_command (filename);
return True;
}
case 4: { /* xtmemory */
HChar* filename;
filename = VG_(strtok_r) (NULL, " ", &ssaveptr);
ms_xtmemory_report (filename, False);
return True;
}
default:
tl_assert(0);
return False;
}
}
static void ms_print_stats (void)
{
#define STATS(format, args...) \
VG_(dmsg)("Massif: " format, ##args)
STATS("heap allocs: %u\n", n_heap_allocs);
STATS("heap reallocs: %u\n", n_heap_reallocs);
STATS("heap frees: %u\n", n_heap_frees);
STATS("ignored heap allocs: %u\n", n_ignored_heap_allocs);
STATS("ignored heap frees: %u\n", n_ignored_heap_frees);
STATS("ignored heap reallocs: %u\n", n_ignored_heap_reallocs);
STATS("stack allocs: %u\n", n_stack_allocs);
STATS("skipped snapshots: %u\n", n_skipped_snapshots);
STATS("real snapshots: %u\n", n_real_snapshots);
STATS("detailed snapshots: %u\n", n_detailed_snapshots);
STATS("peak snapshots: %u\n", n_peak_snapshots);
STATS("cullings: %u\n", n_cullings);
#undef STATS
}
//------------------------------------------------------------//
//--- Finalisation ---//
//------------------------------------------------------------//
static void ms_fini(Int exit_status)
{
ms_xtmemory_report(VG_(clo_xtree_memory_file), True);
// Output.
write_snapshots_array_to_file();
if (VG_(clo_stats))
ms_print_stats();
}
//------------------------------------------------------------//
//--- Initialisation ---//
//------------------------------------------------------------//
static void ms_post_clo_init(void)
{
Int i;
HChar* LD_PRELOAD_val;
/* We will record execontext up to clo_depth + overestimate and
we will store this as ec => we need to increase the backtrace size
if smaller than what we will store. */
if (VG_(clo_backtrace_size) < clo_depth + MAX_OVERESTIMATE)
VG_(clo_backtrace_size) = clo_depth + MAX_OVERESTIMATE;
// Check options.
if (clo_pages_as_heap) {
if (clo_stacks) {
VG_(fmsg_bad_option)("--pages-as-heap=yes",
"Cannot be used together with --stacks=yes");
}
}
if (!clo_heap) {
clo_pages_as_heap = False;
}
// If --pages-as-heap=yes we don't want malloc replacement to occur. So we
// disable vgpreload_massif-$PLATFORM.so by removing it from LD_PRELOAD (or
// platform-equivalent). This is a bit of a hack, but LD_PRELOAD is setup
// well before tool initialisation, so this seems the best way to do it.
if (clo_pages_as_heap) {
HChar* s1;
HChar* s2;
clo_heap_admin = 0; // No heap admin on pages.
LD_PRELOAD_val = VG_(getenv)( VG_(LD_PRELOAD_var_name) );
tl_assert(LD_PRELOAD_val);
VERB(2, "clo_pages_as_heap orig LD_PRELOAD '%s'\n", LD_PRELOAD_val);
// Make sure the vgpreload_core-$PLATFORM entry is there, for sanity.
s1 = VG_(strstr)(LD_PRELOAD_val, "vgpreload_core");
tl_assert(s1);
// Now find the vgpreload_massif-$PLATFORM entry.
s1 = VG_(strstr)(LD_PRELOAD_val, "vgpreload_massif");
tl_assert(s1);
s2 = s1;
// Position s1 on the previous ':', which must be there because
// of the preceding vgpreload_core-$PLATFORM entry.
for (; *s1 != ':'; s1--)
;
// Position s2 on the next ':' or \0
for (; *s2 != ':' && *s2 != '\0'; s2++)
;
// Move all characters from s2 to s1
while ((*s1++ = *s2++))
;
VERB(2, "clo_pages_as_heap cleaned LD_PRELOAD '%s'\n", LD_PRELOAD_val);
}
// Print alloc-fns and ignore-fns, if necessary.
if (VG_(clo_verbosity) > 1) {
VERB(1, "alloc-fns:\n");
for (i = 0; i < VG_(sizeXA)(alloc_fns); i++) {
HChar** fn_ptr = VG_(indexXA)(alloc_fns, i);
VERB(1, " %s\n", *fn_ptr);
}
VERB(1, "ignore-fns:\n");
if (0 == VG_(sizeXA)(ignore_fns)) {
VERB(1, " <empty>\n");
}
for (i = 0; i < VG_(sizeXA)(ignore_fns); i++) {
HChar** fn_ptr = VG_(indexXA)(ignore_fns, i);
VERB(1, " %d: %s\n", i, *fn_ptr);
}
}
// Events to track.
if (clo_stacks) {
VG_(track_new_mem_stack) ( new_mem_stack );
VG_(track_die_mem_stack) ( die_mem_stack );
VG_(track_new_mem_stack_signal) ( new_mem_stack_signal );
VG_(track_die_mem_stack_signal) ( die_mem_stack_signal );
}
if (clo_pages_as_heap) {
VG_(track_new_mem_startup) ( ms_new_mem_startup );
VG_(track_new_mem_brk) ( ms_new_mem_brk );
VG_(track_new_mem_mmap) ( ms_new_mem_mmap );
VG_(track_copy_mem_remap) ( ms_copy_mem_remap );
VG_(track_die_mem_brk) ( ms_die_mem_brk );
VG_(track_die_mem_munmap) ( ms_die_mem_munmap );
}
// Initialise snapshot array, and sanity-check it.
snapshots = VG_(malloc)("ms.main.mpoci.1",
sizeof(Snapshot) * clo_max_snapshots);
// We don't want to do snapshot sanity checks here, because they're
// currently uninitialised.
for (i = 0; i < clo_max_snapshots; i++) {
clear_snapshot( & snapshots[i], /*do_sanity_check*/False );
}
sanity_check_snapshots_array();
if (VG_(clo_xtree_memory) == Vg_XTMemory_Full)
// Activate full xtree memory profiling.
// As massif already filters one top function, use as filter
// VG_(XT_filter_maybe_below_main).
VG_(XTMemory_Full_init)(VG_(XT_filter_maybe_below_main));
}
static void ms_pre_clo_init(void)
{
VG_(details_name) ("Massif");
VG_(details_version) (NULL);
VG_(details_description) ("a heap profiler");
VG_(details_copyright_author)(
"Copyright (C) 2003-2017, and GNU GPL'd, by Nicholas Nethercote");
VG_(details_bug_reports_to) (VG_BUGS_TO);
VG_(details_avg_translation_sizeB) ( 330 );
VG_(clo_vex_control).iropt_register_updates_default
= VG_(clo_px_file_backed)
= VexRegUpdSpAtMemAccess; // overridable by the user.
// Basic functions.
VG_(basic_tool_funcs) (ms_post_clo_init,
ms_instrument,
ms_fini);
// Needs.
VG_(needs_libc_freeres)();
VG_(needs_cxx_freeres)();
VG_(needs_command_line_options)(ms_process_cmd_line_option,
ms_print_usage,
ms_print_debug_usage);
VG_(needs_client_requests) (ms_handle_client_request);
VG_(needs_sanity_checks) (ms_cheap_sanity_check,
ms_expensive_sanity_check);
VG_(needs_print_stats) (ms_print_stats);
VG_(needs_malloc_replacement) (ms_malloc,
ms___builtin_new,
ms___builtin_vec_new,
ms_memalign,
ms_calloc,
ms_free,
ms___builtin_delete,
ms___builtin_vec_delete,
ms_realloc,
ms_malloc_usable_size,
0 );
// HP_Chunks.
HP_chunk_poolalloc = VG_(newPA)
(sizeof(HP_Chunk),
1000,
VG_(malloc),
"massif MC_Chunk pool",
VG_(free));
malloc_list = VG_(HT_construct)( "Massif's malloc list" );
// Heap XTree
heap_xt = VG_(XT_create)(VG_(malloc),
"ms.xtrees",
VG_(free),
sizeof(SizeT),
init_szB, add_szB, sub_szB,
filter_IPs);
// Initialise alloc_fns and ignore_fns.
init_alloc_fns();
init_ignore_fns();
// Initialise args_for_massif.
args_for_massif = VG_(newXA)(VG_(malloc), "ms.main.mprci.1",
VG_(free), sizeof(HChar*));
}
VG_DETERMINE_INTERFACE_VERSION(ms_pre_clo_init)
//--------------------------------------------------------------------//
//--- end ---//
//--------------------------------------------------------------------//