blob: b83c900d632d22d51a4a250a90f4c37764155267 [file] [log] [blame]
//--------------------------------------------------------------------*/
//--- 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) 2003-2007 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 -- critical for release:
// - do a graph-drawing test
// - write a good basic test that shows how the tool works, suitable for
// documentation
// - write documentation
// - make --threshold and --peak-inaccuracy fractional
// - do filename properly, clean up Valgrind-wide log file naming mess.
// Expected behaviour:
// - Main log file:
// default --> stderr
// --log-file=X --> X.<pid>
// --log-file-exactly=X --> X
// --log-file-qualifier=QUAL --> [error]
// --log-file=X --log-file-qualifier=QUAL --> X.$QUAL
// - Massif out file:
// default --> cachegrind.out.<pid>
// --cg-out-file=X --> X.<pid>
// --cg-out-file-exactly=X --> X
// --cg-out-file-qualifier=QUAL --> [error]
// --cg-out-file=X --cg-out-file-qualifier=QUAL --> X.$QUAL
// - Likewise for Cachegrind, but with --cg-out/cg.out.
// - And in cg_annotate, remove the --<pid> option.
// - Likewise for Callgrind, but with --cl-out/cl.out (?)
// - And don't create .1, .2 etc suffixed files.
//
// Todo -- nice, but less critical:
// - 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 client requests
// - (Michael Meeks): have an interactive way to request a dump
// (callgrind_control-style)
// - "profile now"
// - "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!)
// - allow truncation of long fnnames if the exact line number is
// identified? [hmm, could make getting the name of alloc-fns more
// difficult] [could dump full names to file, truncate in ms_print]
// - make --show-below-main=no work
//
// 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
//
// - get_XCon accounts for about 9% of konqueror startup time. Try
// keeping XPt children sorted by 'ip' and use binary search in get_XCon.
// Requires factoring out binary search code from various places into a
// VG_(bsearch) function.
//
// Todo -- low priority:
// - Consider 'instructions executed' as a time unit -- more regular than
// ms, less artificial than B (bug #121629).
// - In each XPt, record both bytes and the number of allocations, and
// possibly the global number of allocations.
// - (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."
//
// Examine and fix bugs on bugzilla:
// IGNORE:
// 112163 nor MASSIF crashed with signal 7 (SIGBUS) after running 2 days
// - weird, crashes in VEX, ignore
// 82871 nor Massif output function names too short
// - on .ps graph, now irrelevant, ignore
// 129576 nor Massif loses track of memory, incorrect graphs
// - dunno, hard to reproduce, ignore
// 132132 nor massif --format=html output does not do html entity escaping
// - only for HTML output, irrelevant, ignore
// 132950 Heap alloc/usage summary
// - doesn't seem that interesting or general
//
// FIXED/NOW IRRELEVANT:
// 89061 cra Massif: ms_main.c:485 (get_XCon): Assertion `xpt->max_chi...
// - relevant code now gone
// 143062 cra massif crashes on app exit with signal 8 SIGFPE
// - fixed
// 95483 nor massif feature request: include peak allocation in report
// - implemented in Massif2
// 92615 nor Write output from Massif at crash
// - this happens unless Massif2 itself crashes
// 121629 add instruction-counting mode for timing
// - time-unit=B is similar, plus I'm considering this above anyway
// 142197 nor massif tool ignores --massif:alloc-fn parameters in .valg...
// - fixed in trunk
// 142491 nor Maximise use of alloc_fns array
// - addressed, it's now an XArray and thus unlimited in size
// 144453 (get_XCon): Assertion 'xpt->max_children != 0' failed.
// - relevant code now gone
//
// POSSIBLY FIXED BY BETTER SANITY CHECKING, BUT HARD TO TELL:
// 141631 Massif: percentages don't add up correctly
// - better sanity-checking should help this greatly
// 142706 massif numbers don't seem to add up
// - better sanity-checking should help this greatly
// 149504 Assertion hit on alloc_xpt->curr_space >= -space_delta
// - better sanity-checking should help this greatly
// 146456 (update_XCon): Assertion 'xpt->curr_space >= -space_delta' failed.
// - better sanity-checking should help this greatly
//
// 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_replacemalloc.h"
#include "pub_tool_stacktrace.h"
#include "pub_tool_tooliface.h"
#include "pub_tool_xarray.h"
#include "pub_tool_clientstate.h"
#include "valgrind.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 a tree representing the
// call tree beneath all the allocation functions like malloc().
//
// "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 (VG_(clo_verbosity) > verb) { \
VG_(message)(Vg_DebugMsg, "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_stack_allocs = 0;
static UInt n_stack_frees = 0;
static UInt n_xpts = 0;
static UInt n_xpt_init_expansions = 0;
static UInt n_xpt_later_expansions = 0;
static UInt n_sxpt_allocs = 0;
static UInt n_sxpt_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;
static UInt n_XCon_redos = 0;
//------------------------------------------------------------//
//--- Globals ---//
//------------------------------------------------------------//
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;
// Current directory at startup.
static Char base_dir[VKI_PATH_MAX]; // XXX: currently unused
// 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.
//
static Bool have_started_executing_code = False;
//------------------------------------------------------------//
//--- Alloc fns ---//
//------------------------------------------------------------//
static XArray* alloc_fns;
static void init_alloc_fns(void)
{
// Create the list, and add the default elements.
alloc_fns = VG_(newXA)(VG_(malloc), VG_(free), sizeof(Char*));
#define DO(x) { Char* s = x; VG_(addToXA)(alloc_fns, &s); }
// Ordered 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.
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("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&)");
}
static Bool is_alloc_fn(Char* fnname)
{
Char** alloc_fn_ptr;
Int i;
// Nb: It's a linear search through the list, because we're comparing
// strings rather than pointers to strings.
// Nb: This gets called a lot. It was an OSet, but they're quite slow to
// iterate through so it wasn't a good choice.
for (i = 0; i < VG_(sizeXA)(alloc_fns); i++) {
alloc_fn_ptr = VG_(indexXA)(alloc_fns, i);
if (VG_STREQ(fnname, *alloc_fn_ptr))
return True;
}
return False;
}
//------------------------------------------------------------//
//--- Command line args ---//
//------------------------------------------------------------//
#define MAX_DEPTH 200
typedef enum { TimeMS, TimeB } TimeUnit;
static Char* TimeUnit_to_string(TimeUnit time_unit)
{
switch (time_unit) {
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 SizeT clo_heap_admin = 8;
static Bool clo_stacks = False;
static UInt clo_depth = 30;
static UInt clo_threshold = 100; // 100 == 1%
static UInt clo_peak_inaccuracy = 100; // 100 == 1%
static UInt clo_time_unit = TimeMS;
static UInt clo_detailed_freq = 10;
static UInt clo_max_snapshots = 100;
static XArray* args_for_massif;
static Bool ms_process_cmd_line_option(Char* arg)
{
// Remember the arg for later use.
VG_(addToXA)(args_for_massif, &arg);
VG_BOOL_CLO(arg, "--heap", clo_heap)
else VG_BOOL_CLO(arg, "--stacks", clo_stacks)
// XXX: "--heap-admin= " is accepted!
else VG_NUM_CLO(arg, "--heap-admin", clo_heap_admin)
else VG_NUM_CLO(arg, "--depth", clo_depth)
// XXX: use a fractional number, so no division by 100
else VG_NUM_CLO(arg, "--threshold", clo_threshold)
// XXX: use a fractional number, so no division by 100
else VG_NUM_CLO(arg, "--peak-inaccuracy", clo_peak_inaccuracy)
else VG_NUM_CLO(arg, "--detailed-freq", clo_detailed_freq)
else VG_NUM_CLO(arg, "--max-snapshots", clo_max_snapshots)
else if (VG_CLO_STREQ(arg, "--time-unit=ms")) clo_time_unit = TimeMS;
else if (VG_CLO_STREQ(arg, "--time-unit=B")) clo_time_unit = TimeB;
else if (VG_CLO_STREQN(11, arg, "--alloc-fn=")) {
Char* alloc_fn = &arg[11];
VG_(addToXA)(alloc_fns, &alloc_fn);
}
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=<number> average admin bytes per heap block;"
" ignored if --heap=no [8]\n"
" --stacks=no|yes profile stack(s) [no]\n"
" --depth=<number> depth of contexts [30]\n"
" --alloc-fn=<name> specify <fn> as an alloc function [empty]\n"
" --threshold=<n> significance threshold, in 100ths of a percent\n"
" (eg. <n>=100 shows nodes covering >= 1%% of\n"
" total size, <n>=0 shows all nodes) [100]\n"
" --peak-inaccuracy=<n> closeness of recorded peak to true peak,\n"
" in 100ths of a percent\n"
" --time-unit=ms|B time unit, milliseconds or bytes\n"
" alloc'd/dealloc'd on the heap [ms]\n"
" --detailed-freq=<N> every Nth snapshot should be detailed [10]\n"
" --max-snapshots=<N> maximum number of snapshots recorded [100]\n"
);
VG_(replacement_malloc_print_usage)();
}
static void ms_print_debug_usage(void)
{
VG_(replacement_malloc_print_debug_usage)();
}
//------------------------------------------------------------//
//--- XPts, XTrees and XCons ---//
//------------------------------------------------------------//
// An XPt represents an "execution point", ie. a code address. Each XPt is
// part of a tree of XPts (an "execution tree", or "XTree"). The details of
// the heap are represented by a single XTree.
//
// The root of the tree is 'alloc_xpt', which represents all allocation
// functions, eg:
// - malloc/calloc/realloc/memalign/new/new[];
// - user-specified allocation functions (using --alloc-fn);
// - custom allocation (MALLOCLIKE) points
// It's a bit of a fake XPt (ie. its 'ip' is zero), and is only used because
// it makes the code simpler.
//
// Any child of 'alloc_xpt' is called a "top-XPt". The XPts at the bottom
// of an XTree (leaf nodes) are "bottom-XPTs".
//
// Each path from a top-XPt to a bottom-XPt through an XTree gives an
// execution context ("XCon"), ie. a stack trace. (And sub-paths represent
// stack sub-traces.) The number of XCons in an XTree is equal to the
// number of bottom-XPTs in that XTree.
//
// alloc_xpt XTrees are bi-directional.
// | ^
// v |
// > parent < Example: if child1() calls parent() and child2()
// / | \ also calls parent(), and parent() calls malloc(),
// | / \ | the XTree will look like this.
// | v v |
// child1 child2
//
// XTrees and XPts are mirrored by SXTrees and SXPts, where the 'S' is short
// for "saved". When the XTree is duplicated for a snapshot, we duplicate
// it as an SXTree, which is similar but omits some things it does not need,
// and aggregates up insignificant nodes. This is important as an SXTree is
// typically much smaller than an XTree.
// XXX: make XPt and SXPt extensible arrays, to avoid having to do two
// allocations per Pt.
typedef struct _XPt XPt;
struct _XPt {
Addr ip; // code address
// Bottom-XPts: space for the precise context.
// Other XPts: space of all the descendent bottom-XPts.
// Nb: this value goes up and down as the program executes.
SizeT szB;
XPt* parent; // pointer to parent XPt
// Children.
// n_children and max_children are 32-bit integers. 16-bit integers
// are too small -- a very big program might have more than 65536
// allocation points (ie. top-XPts) -- Konqueror starting up has 1800.
UInt n_children; // number of children
UInt max_children; // capacity of children array
XPt** children; // pointers to children XPts
};
typedef
enum {
SigSXPt,
InsigSXPt
}
SXPtTag;
typedef struct _SXPt SXPt;
struct _SXPt {
SXPtTag tag;
SizeT szB; // memory size for the node, be it Sig or Insig
union {
// An SXPt representing a single significant code location. Much like
// an XPt, minus the fields that aren't necessary.
struct {
Addr ip;
UInt n_children;
SXPt** children;
}
Sig;
// An SXPt representing one or more code locations, all below the
// significance threshold.
struct {
Int n_xpts; // number of aggregated XPts
}
Insig;
};
};
// Fake XPt representing all allocation functions like malloc(). Acts as
// parent node to all top-XPts.
static XPt* alloc_xpt;
// Cheap allocation for blocks that never need to be freed. Saves about 10%
// for Konqueror startup with --depth=40.
static void* perm_malloc(SizeT n_bytes)
{
static Addr hp = 0; // current heap pointer
static Addr hp_lim = 0; // maximum usable byte in current block
#define SUPERBLOCK_SIZE (1 << 20) // 1 MB
if (hp + n_bytes > hp_lim) {
hp = (Addr)VG_(am_shadow_alloc)(SUPERBLOCK_SIZE);
if (hp == 0)
VG_(out_of_memory_NORETURN)( "massif:perm_malloc",
SUPERBLOCK_SIZE);
hp_lim = hp + SUPERBLOCK_SIZE - 1;
}
hp += n_bytes;
return (void*)(hp - n_bytes);
}
static XPt* new_XPt(Addr ip, XPt* parent)
{
// XPts are never freed, so we can use perm_malloc to allocate them.
// Note that we cannot use perm_malloc for the 'children' array, because
// that needs to be resizable.
XPt* xpt = perm_malloc(sizeof(XPt));
xpt->ip = ip;
xpt->szB = 0;
xpt->parent = parent;
// We don't initially allocate any space for children. We let that
// happen on demand. Many XPts (ie. all the bottom-XPts) don't have any
// children anyway.
xpt->n_children = 0;
xpt->max_children = 0;
xpt->children = NULL;
// Update statistics
n_xpts++;
return xpt;
}
static void add_child_xpt(XPt* parent, XPt* child)
{
// Expand 'children' if necessary.
tl_assert(parent->n_children <= parent->max_children);
if (parent->n_children == parent->max_children) {
if (parent->max_children == 0) {
parent->max_children = 4;
parent->children = VG_(malloc)( parent->max_children * sizeof(XPt*) );
n_xpt_init_expansions++;
} else {
parent->max_children *= 2; // Double size
parent->children = VG_(realloc)( parent->children,
parent->max_children * sizeof(XPt*) );
n_xpt_later_expansions++;
}
}
// Insert new child XPt in parent's children list.
parent->children[ parent->n_children++ ] = child;
}
// Reverse comparison for a reverse sort -- biggest to smallest.
static Int SXPt_revcmp_szB(void* n1, void* n2)
{
SXPt* sxpt1 = *(SXPt**)n1;
SXPt* sxpt2 = *(SXPt**)n2;
return ( sxpt1->szB < sxpt2->szB ? 1
: sxpt1->szB > sxpt2->szB ? -1
: 0);
}
//------------------------------------------------------------//
//--- XTree Operations ---//
//------------------------------------------------------------//
// Duplicates an XTree as an SXTree.
static SXPt* dup_XTree(XPt* xpt, SizeT total_szB)
{
Int i, n_sig_children, n_insig_children, n_child_sxpts;
SizeT insig_children_szB, sig_child_threshold_szB;
SXPt* sxpt;
// Number of XPt children Action for SXPT
// ------------------ ---------------
// 0 sig, 0 insig alloc 0 children
// N sig, 0 insig alloc N children, dup all
// N sig, M insig alloc N+1, dup first N, aggregate remaining M
// 0 sig, M insig alloc 1, aggregate M
// Work out how big a child must be to be significant. If the current
// total_szB is zero, then we set it to 1, which means everything will be
// judged insignificant -- this is sensible, as there's no point showing
// any detail for this case. Unless they used --threshold=0, in which
// case we show them everything because that's what they asked for.
//
// Nb: We do this once now, rather than once per child, because if we do
// that the cost of all the divisions adds up to something significant.
if (total_szB == 0 && clo_threshold != 0) {
sig_child_threshold_szB = 1;
} else {
sig_child_threshold_szB = (((ULong)total_szB) * clo_threshold) / 10000ULL;
}
// How many children are significant? And do we need an aggregate SXPt?
n_sig_children = 0;
for (i = 0; i < xpt->n_children; i++) {
if (xpt->children[i]->szB >= sig_child_threshold_szB) {
n_sig_children++;
}
}
n_insig_children = xpt->n_children - n_sig_children;
n_child_sxpts = n_sig_children + ( n_insig_children > 0 ? 1 : 0 );
// Duplicate the XPt.
sxpt = VG_(malloc)(sizeof(SXPt));
n_sxpt_allocs++;
sxpt->tag = SigSXPt;
sxpt->szB = xpt->szB;
sxpt->Sig.ip = xpt->ip;
sxpt->Sig.n_children = n_child_sxpts;
// Create the SXPt's children.
if (n_child_sxpts > 0) {
Int j;
SizeT sig_children_szB = 0;
sxpt->Sig.children = VG_(malloc)(n_child_sxpts * sizeof(SXPt*));
// Duplicate the significant children.
j = 0;
for (i = 0; i < xpt->n_children; i++) {
if (xpt->children[i]->szB >= sig_child_threshold_szB) {
sxpt->Sig.children[j++] = dup_XTree(xpt->children[i], total_szB);
sig_children_szB += xpt->children[i]->szB;
}
}
// Create the SXPt for the insignificant children, if any, and put it
// in the last child entry.
insig_children_szB = sxpt->szB - sig_children_szB;
if (n_insig_children > 0) {
// Nb: We 'n_sxpt_allocs' here because creating an Insig SXPt
// doesn't involve a call to dup_XTree().
SXPt* insig_sxpt = VG_(malloc)(sizeof(SXPt));
n_sxpt_allocs++;
insig_sxpt->tag = InsigSXPt;
insig_sxpt->szB = insig_children_szB;
insig_sxpt->Insig.n_xpts = n_insig_children;
sxpt->Sig.children[n_sig_children] = insig_sxpt;
}
} else {
sxpt->Sig.children = NULL;
}
return sxpt;
}
static void free_SXTree(SXPt* sxpt)
{
Int i;
tl_assert(sxpt != NULL);
switch (sxpt->tag) {
case SigSXPt:
// Free all children SXPts, then the children array.
for (i = 0; i < sxpt->Sig.n_children; i++) {
free_SXTree(sxpt->Sig.children[i]);
sxpt->Sig.children[i] = NULL;
}
VG_(free)(sxpt->Sig.children); sxpt->Sig.children = NULL;
break;
case InsigSXPt:
break;
default: tl_assert2(0, "free_SXTree: unknown SXPt tag");
}
// Free the SXPt itself.
VG_(free)(sxpt); sxpt = NULL;
n_sxpt_frees++;
}
// Sanity checking: we periodically check the heap XTree with
// ms_expensive_sanity_check.
static void sanity_check_XTree(XPt* xpt, XPt* parent)
{
Int i;
tl_assert(xpt != NULL);
// Check back-pointer.
tl_assert2(xpt->parent == parent,
"xpt->parent = %p, parent = %p\n", xpt->parent, parent);
// Check children counts look sane.
tl_assert(xpt->n_children <= xpt->max_children);
// Check the sum of any children szBs equals the XPt's szB. Check the
// children at the same time.
if (xpt->n_children > 0) {
SizeT children_sum_szB = 0;
for (i = 0; i < xpt->n_children; i++) {
sanity_check_XTree(xpt->children[i], xpt);
children_sum_szB += xpt->children[i]->szB;
}
tl_assert(children_sum_szB == xpt->szB);
}
}
// Sanity checking: we check SXTrees (which are in snapshots) after
// snapshots are created, before they are deleted, and before they are
// printed.
static void sanity_check_SXTree(SXPt* sxpt)
{
Int i;
tl_assert(sxpt != NULL);
// Check the sum of any children szBs equals the SXPt's szB. Check the
// children at the same time.
switch (sxpt->tag) {
case SigSXPt: {
if (sxpt->Sig.n_children > 0) {
SizeT children_sum_szB = 0;
for (i = 0; i < sxpt->Sig.n_children; i++) {
sanity_check_SXTree(sxpt->Sig.children[i]);
children_sum_szB += sxpt->Sig.children[i]->szB;
}
tl_assert(children_sum_szB == sxpt->szB);
}
break;
}
case InsigSXPt:
break; // do nothing
default: tl_assert2(0, "sanity_check_SXTree: unknown SXPt tag");
}
}
//------------------------------------------------------------//
//--- XCon Operations ---//
//------------------------------------------------------------//
// This is the limit on the number of removed alloc-fns that can be in a
// single XCon.
#define MAX_OVERESTIMATE 50
#define MAX_IPS (MAX_DEPTH + MAX_OVERESTIMATE)
// Get the stack trace for an XCon, 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
Int get_IPs( ThreadId tid, Bool is_custom_alloc, Addr ips[])
{
#define BUF_LEN 1024
Char buf[BUF_LEN];
Int n_ips, i, n_alloc_fns_removed;
Int overestimate;
Bool redo;
// We ask for a few more IPs than clo_depth suggests we need. Then we
// remove every entry that is an alloc-fn. Depending on the
// circumstances, we may need to redo it all, asking for more IPs.
// Details:
// - If the original stack trace is smaller than asked-for, redo=False
// - Else if after filtering we have >= clo_depth IPs, redo=False
// - Else redo=True
// In other words, to redo, we'd have to get a stack trace as big as we
// asked for and remove more than 'overestimate' alloc-fns.
// Main loop.
redo = True; // Assume this to begin with.
for (overestimate = 3; redo; overestimate += 6) {
// This should never happen -- would require MAX_OVERESTIMATE
// alloc-fns to be removed from the stack trace.
if (overestimate > MAX_OVERESTIMATE)
VG_(tool_panic)("get_IPs: ips[] too small, inc. MAX_OVERESTIMATE?");
// Ask for more IPs than clo_depth suggests we need.
n_ips = VG_(get_StackTrace)( tid, ips, clo_depth + overestimate,
0/*first_ip_delta*/ );
tl_assert(n_ips > 0);
// If the original stack trace is smaller than asked-for, redo=False.
if (n_ips < clo_depth + overestimate) { redo = False; }
// If it's a non-custom block, we will always remove the first stack
// trace entry (which will be one of malloc, __builtin_new, etc).
n_alloc_fns_removed = ( is_custom_alloc ? 0 : 1 );
// Filter out alloc fns. If it's a non-custom block, we remove the
// first entry (which will be one of malloc, __builtin_new, etc)
// without looking at it, because VG_(get_fnname) is expensive (it
// involves calls to VG_(malloc)/VG_(free)).
for (i = n_alloc_fns_removed; i < n_ips; i++) {
if (VG_(get_fnname)(ips[i], buf, BUF_LEN)) {
if (is_alloc_fn(buf)) {
n_alloc_fns_removed++;
} else {
break;
}
}
}
// Remove the alloc fns by shuffling the rest down over them.
n_ips -= n_alloc_fns_removed;
for (i = 0; i < n_ips; i++) {
ips[i] = ips[i + n_alloc_fns_removed];
}
// If after filtering we have >= clo_depth IPs, redo=False
if (n_ips >= clo_depth) {
redo = False;
n_ips = clo_depth; // Ignore any IPs below --depth.
}
if (redo) {
n_XCon_redos++;
}
}
return n_ips;
}
// Gets an XCon and puts it in the tree. Returns the XCon's bottom-XPt.
static XPt* get_XCon( ThreadId tid, Bool is_custom_alloc )
{
Addr ips[MAX_IPS];
Int i;
XPt* xpt = alloc_xpt;
// After this call, the IPs we want are in ips[0]..ips[n_ips-1].
Int n_ips = get_IPs(tid, is_custom_alloc, ips);
// Now do the search/insertion of the XCon.
for (i = 0; i < n_ips; i++) {
Addr ip = ips[i];
Int ch;
// Look for IP in xpt's children.
// Linear search, ugh -- about 10% of time for konqueror startup tried
// caching last result, only hit about 4% for konqueror.
// Nb: this search hits about 98% of the time for konqueror
for (ch = 0; True; ch++) {
if (ch == xpt->n_children) {
// IP not found in the children.
// Create and add new child XPt, then stop.
XPt* new_child_xpt = new_XPt(ip, xpt);
add_child_xpt(xpt, new_child_xpt);
xpt = new_child_xpt;
break;
} else if (ip == xpt->children[ch]->ip) {
// Found the IP in the children, stop.
xpt = xpt->children[ch];
break;
}
}
}
tl_assert(0 == xpt->n_children); // Must be bottom-XPt
return xpt;
}
// Update 'szB' of every XPt in the XCon, by percolating upwards.
static void update_XCon(XPt* xpt, SSizeT space_delta)
{
tl_assert(True == clo_heap);
tl_assert(NULL != xpt);
tl_assert(0 == xpt->n_children); // must be bottom-XPt
if (0 == space_delta)
return;
while (xpt != alloc_xpt) {
if (space_delta < 0) tl_assert(xpt->szB >= -space_delta);
xpt->szB += space_delta;
xpt = xpt->parent;
}
if (space_delta < 0) tl_assert(alloc_xpt->szB >= -space_delta);
alloc_xpt->szB += space_delta;
}
//------------------------------------------------------------//
//--- 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.
// Time is measured either in ms or bytes, depending on the --time-unit
// option. It's a Long because it can exceed 32-bits reasonably easily, and
// because we need to allow negative values to represent unset times.
typedef Long Time;
#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;
SXPt* alloc_sxpt; // Heap XTree root, 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->alloc_sxpt == NULL);
return False;
} else {
tl_assert(snapshot->time != UNUSED_SNAPSHOT_TIME);
return True;
}
}
static Bool is_detailed_snapshot(Snapshot* snapshot)
{
return (snapshot->alloc_sxpt ? 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)
{
if (snapshot->alloc_sxpt) {
sanity_check_SXTree(snapshot->alloc_sxpt);
}
}
// 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 heap
// 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->alloc_sxpt = NULL;
}
// This zeroes all the fields in the snapshot, and frees the heap XTree 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.
SXPt* tmp_sxpt = snapshot->alloc_sxpt;
clear_snapshot(snapshot, /*do_sanity_check*/True);
if (tmp_sxpt) {
free_SXTree(tmp_sxpt);
}
}
static void VERB_snapshot(Int verbosity, Char* prefix, Int i)
{
Snapshot* snapshot = &snapshots[i];
Char* 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:%ld, ex:%ld, st:%ld)",
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...");
// 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) {
Char buf[64];
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)", 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_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)",
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 == 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.
static void
take_snapshot(Snapshot* snapshot, SnapshotKind kind, Time time,
Bool is_detailed, Char* what)
{
tl_assert(!is_snapshot_in_use(snapshot));
tl_assert(have_started_executing_code);
// Heap and heap admin.
if (clo_heap) {
snapshot->heap_szB = heap_szB;
if (is_detailed) {
SizeT total_szB = heap_szB + heap_extra_szB + stacks_szB;
snapshot->alloc_sxpt = dup_XTree(alloc_xpt, total_szB);
tl_assert( alloc_xpt->szB == heap_szB);
tl_assert(snapshot->alloc_sxpt->szB == heap_szB);
}
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 = 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, Char* 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;
Time time = get_time();
switch (kind) {
case Normal:
// Only do a snapshot if it's time.
if (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 =
(((ULong)peak_snapshot_total_szB) * clo_peak_inaccuracy) / 10000ULL;
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, time, is_detailed, what);
// 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_skipped_snapshots_since_last_snapshot,
( n_skipped_snapshots_since_last_snapshot == 1 ? "" : "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 = 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 )
{
sanity_check_XTree(alloc_xpt, /*parent*/NULL);
sanity_check_snapshots_array();
return True;
}
//------------------------------------------------------------//
//--- Heap management ---//
//------------------------------------------------------------//
// Metadata for heap blocks. Each one contains a pointer to a bottom-XPt,
// which is a foothold into the XCon at which it was allocated. From
// HP_Chunks, XPt 'space' fields are 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
XPt* where; // Where allocated; bottom-XPt
}
HP_Chunk;
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* new_block ( ThreadId tid, void* p, SizeT req_szB, SizeT req_alignB,
Bool is_zeroed )
{
HP_Chunk* hc;
Bool is_custom_alloc = (NULL != p);
SizeT actual_szB, slop_szB;
if (req_szB < 0) return NULL;
// Allocate and zero if necessary
if (!p) {
p = VG_(cli_malloc)( req_alignB, req_szB );
if (!p) {
return NULL;
}
if (is_zeroed) VG_(memset)(p, 0, req_szB);
actual_szB = VG_(malloc_usable_size)(p);
tl_assert(actual_szB >= req_szB);
slop_szB = actual_szB - req_szB;
} else {
slop_szB = 0;
}
// Make new HP_Chunk node, add to malloc_list
hc = VG_(malloc)(sizeof(HP_Chunk));
hc->req_szB = req_szB;
hc->slop_szB = slop_szB;
hc->data = (Addr)p;
hc->where = NULL;
VG_(HT_add_node)(malloc_list, hc);
if (clo_heap) {
VERB(3, "<<< new_mem_heap (%lu, %lu)", req_szB, slop_szB);
// Update statistics.
n_heap_allocs++;
// Update heap stats.
update_heap_stats(req_szB, clo_heap_admin + slop_szB);
// Update XTree.
hc->where = get_XCon( tid, is_custom_alloc );
update_XCon(hc->where, req_szB);
// Maybe take a snapshot.
maybe_take_snapshot(Normal, " alloc");
VERB(3, ">>>");
}
return p;
}
static __inline__
void die_block ( void* p, Bool custom_free )
{
HP_Chunk* hc;
// Remove HP_Chunk from malloc_list
hc = VG_(HT_remove)(malloc_list, (UWord)p);
if (NULL == hc) {
return; // must have been a bogus free()
}
if (clo_heap) {
VERB(3, "<<< die_mem_heap");
// Update statistics
n_heap_frees++;
// Maybe take a peak snapshot, since it's a deallocation.
maybe_take_snapshot(Peak, "de-PEAK");
// Update heap stats.
update_heap_stats(-hc->req_szB, -clo_heap_admin - hc->slop_szB);
// Update XTree.
update_XCon(hc->where, -hc->req_szB);
// Maybe take a snapshot.
maybe_take_snapshot(Normal, "dealloc");
VERB(3, ">>> (-%lu, -%lu)", hc->req_szB, hc->slop_szB);
}
// Actually free the chunk, and the heap block (if necessary)
VG_(free)( hc ); hc = NULL;
if (!custom_free)
VG_(cli_free)( p );
}
static __inline__
void* renew_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;
XPt *old_where, *new_where;
// 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;
if (clo_heap) {
VERB(3, "<<< renew_mem_heap (%lu)", new_req_szB);
// 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");
}
}
// 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);
VG_(cli_free)(p_old);
new_actual_szB = VG_(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 = NULL;
// Update XTree.
if (clo_heap) {
new_where = get_XCon( tid, /*custom_malloc*/False);
hc->where = new_where;
update_XCon(old_where, -old_req_szB);
update_XCon(new_where, new_req_szB);
}
}
// 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) {
// 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");
VERB(3, ">>> (%ld, %ld)",
new_req_szB - old_req_szB, new_slop_szB - old_slop_szB);
}
return p_new;
}
//------------------------------------------------------------//
//--- malloc() et al replacement wrappers ---//
//------------------------------------------------------------//
static void* ms_malloc ( ThreadId tid, SizeT szB )
{
return new_block( tid, NULL, szB, VG_(clo_alignment), /*is_zeroed*/False );
}
static void* ms___builtin_new ( ThreadId tid, SizeT szB )
{
return new_block( tid, NULL, szB, VG_(clo_alignment), /*is_zeroed*/False );
}
static void* ms___builtin_vec_new ( ThreadId tid, SizeT szB )
{
return new_block( tid, NULL, szB, VG_(clo_alignment), /*is_zeroed*/False );
}
static void* ms_calloc ( ThreadId tid, SizeT m, SizeT szB )
{
return new_block( tid, NULL, m*szB, VG_(clo_alignment), /*is_zeroed*/True );
}
static void *ms_memalign ( ThreadId tid, SizeT alignB, SizeT szB )
{
return new_block( tid, NULL, szB, alignB, False );
}
static void ms_free ( ThreadId tid, void* p )
{
die_block( p, /*custom_free*/False );
}
static void ms___builtin_delete ( ThreadId tid, void* p )
{
die_block( p, /*custom_free*/False);
}
static void ms___builtin_vec_delete ( ThreadId tid, void* p )
{
die_block( p, /*custom_free*/False );
}
static void* ms_realloc ( ThreadId tid, void* p_old, SizeT new_szB )
{
return renew_block(tid, p_old, new_szB);
}
//------------------------------------------------------------//
//--- 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(Addr a, SizeT len, Char* what)
{
if (have_started_executing_code) {
VERB(3, "<<< new_mem_stack (%ld)", len);
n_stack_allocs++;
update_stack_stats(len);
maybe_take_snapshot(Normal, what);
VERB(3, ">>>");
}
}
static INLINE void die_mem_stack_2(Addr a, SizeT len, Char* what)
{
if (have_started_executing_code) {
VERB(3, "<<< die_mem_stack (%ld)", -len);
n_stack_frees++;
maybe_take_snapshot(Peak, "stkPEAK");
update_stack_stats(-len);
maybe_take_snapshot(Normal, what);
VERB(3, ">>>");
}
}
static void new_mem_stack(Addr a, SizeT len)
{
new_mem_stack_2(a, len, "stk-new");
}
static void die_mem_stack(Addr a, SizeT len)
{
die_mem_stack_2(a, len, "stk-die");
}
static void new_mem_stack_signal(Addr a, SizeT len)
{
new_mem_stack_2(a, len, "sig-new");
}
static void die_mem_stack_signal(Addr a, SizeT len)
{
die_mem_stack_2(a, len, "sig-die");
}
//------------------------------------------------------------//
//--- Client Requests ---//
//------------------------------------------------------------//
static Bool ms_handle_client_request ( ThreadId tid, UWord* argv, UWord* ret )
{
switch (argv[0]) {
case VG_USERREQ__MALLOCLIKE_BLOCK: {
void* res;
void* p = (void*)argv[1];
SizeT szB = argv[2];
res = new_block( tid, p, szB, /*alignB--ignored*/0, /*is_zeroed*/False );
tl_assert(res == p);
*ret = 0;
return True;
}
case VG_USERREQ__FREELIKE_BLOCK: {
void* p = (void*)argv[1];
die_block( p, /*custom_free*/True );
*ret = 0;
return True;
}
default:
*ret = 0;
return False;
}
}
//------------------------------------------------------------//
//--- Instrumentation ---//
//------------------------------------------------------------//
static
IRSB* ms_instrument ( VgCallbackClosure* closure,
IRSB* bb_in,
VexGuestLayout* layout,
VexGuestExtents* vge,
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");
}
return bb_in;
}
//------------------------------------------------------------//
//--- Writing snapshots ---//
//------------------------------------------------------------//
// XXX: do the filename properly, eventually
static Char* massif_out_file = "massif.out";
#define FP_BUF_SIZE 1024
Char FP_buf[FP_BUF_SIZE];
// XXX: implement f{,n}printf in m_libcprint.c eventually, and use it here.
// Then change Cachegrind to use it too.
#define FP(format, args...) ({ \
VG_(snprintf)(FP_buf, FP_BUF_SIZE, format, ##args); \
VG_(write)(fd, (void*)FP_buf, VG_(strlen)(FP_buf)); \
})
// Nb: uses a static buffer, each call trashes the last string returned.
static Char* make_perc(ULong x, ULong y)
{
static Char mbuf[32];
// tl_assert(x <= y); XXX; put back in later...
// XXX: I'm not confident that VG_(percentify) works as it should...
VG_(percentify)(x, y, 2, 6, mbuf);
// XXX: this is bogus if the denominator was zero -- resulting string is
// something like "0 --%")
if (' ' == mbuf[0]) mbuf[0] = '0';
return mbuf;
}
static void pp_snapshot_SXPt(Int fd, SXPt* sxpt, Int depth, Char* depth_str,
Int depth_str_len,
SizeT snapshot_heap_szB, SizeT snapshot_total_szB)
{
#define BUF_LEN 1024
Int i, n_insig_children_sxpts;
Char* perc;
Char ip_desc_array[BUF_LEN];
Char* ip_desc = ip_desc_array;
SXPt* pred = NULL;
SXPt* child = NULL;
switch (sxpt->tag) {
case SigSXPt:
// Print the SXPt itself.
if (sxpt->Sig.ip == 0) {
ip_desc =
"(heap allocation functions) malloc/new/new[], --alloc-fns, etc.";
} else {
// If it's main-or-below-main, we (if appropriate) ignore everything
// below it by pretending it has no children.
// XXX: get this properly. Also, don't hard-code "(below main)"
// here -- look at the "(below main)"/"__libc_start_main" mess
// (m_stacktrace.c and m_demangle.c).
// [Nb: Josef wants --show-below-main to work for his fn entry/exit
// tracing]
Bool should_hide_below_main = /*!VG_(clo_show_below_main)*/True;
if (should_hide_below_main &&
VG_(get_fnname)(sxpt->Sig.ip, ip_desc, BUF_LEN) &&
(VG_STREQ(ip_desc, "main") || VG_STREQ(ip_desc, "(below main)")))
{
sxpt->Sig.n_children = 0;
}
// We need the -1 to get the line number right, But I'm not sure why.
ip_desc = VG_(describe_IP)(sxpt->Sig.ip-1, ip_desc, BUF_LEN);
}
perc = make_perc(sxpt->szB, snapshot_total_szB);
FP("%sn%d: %lu %s\n",
depth_str, sxpt->Sig.n_children, sxpt->szB, ip_desc);
// Indent.
tl_assert(depth+1 < depth_str_len-1); // -1 for end NUL char
depth_str[depth+0] = ' ';
depth_str[depth+1] = '\0';
// Sort SXPt's children by szB (reverse order: biggest to smallest).
// Nb: we sort them here, rather than earlier (eg. in dup_XTree), for
// two reasons. First, if we do it during dup_XTree, it can get
// expensive (eg. 15% of execution time for konqueror
// startup/shutdown). Second, this way we get the Insig SXPt (if one
// is present) in its sorted position, not at the end.
VG_(ssort)(sxpt->Sig.children, sxpt->Sig.n_children, sizeof(SXPt*),
SXPt_revcmp_szB);
// Print the SXPt's children. They should already be in sorted order.
n_insig_children_sxpts = 0;
for (i = 0; i < sxpt->Sig.n_children; i++) {
pred = child;
child = sxpt->Sig.children[i];
if (InsigSXPt == child->tag)
n_insig_children_sxpts++;
// Ok, print the child.
pp_snapshot_SXPt(fd, child, depth+1, depth_str, depth_str_len,
snapshot_heap_szB, snapshot_total_szB);
// Unindent.
depth_str[depth+0] = '\0';
depth_str[depth+1] = '\0';
}
// There should be 0 or 1 Insig children SXPts.
tl_assert(n_insig_children_sxpts <= 1);
break;
case InsigSXPt: {
Char* s = ( sxpt->Insig.n_xpts == 1 ? "," : "s, all" );
perc = make_perc(sxpt->szB, snapshot_total_szB);
FP("%sn0: %lu in %d place%s below massif's threshold (%s)\n",
depth_str, sxpt->szB, sxpt->Insig.n_xpts, s,
make_perc(clo_threshold, 10000));
break;
}
default:
tl_assert2(0, "pp_snapshot_SXPt: unrecognised SXPt tag");
}
}
static void pp_snapshot(Int fd, Snapshot* snapshot, Int snapshot_n)
{
sanity_check_snapshot(snapshot);
FP("#-----------\n");
FP("snapshot=%d\n", snapshot_n);
FP("#-----------\n");
FP("time=%lld\n", snapshot->time);
FP("mem_heap_B=%lu\n", snapshot->heap_szB);
FP("mem_heap_extra_B=%lu\n", snapshot->heap_extra_szB);
FP("mem_stacks_B=%lu\n", snapshot->stacks_szB);
if (is_detailed_snapshot(snapshot)) {
// Detailed snapshot -- print heap tree.
Int depth_str_len = clo_depth + 3;
Char* depth_str = VG_(malloc)(sizeof(Char) * depth_str_len);
SizeT snapshot_total_szB =
snapshot->heap_szB + snapshot->heap_extra_szB + snapshot->stacks_szB;
depth_str[0] = '\0'; // Initialise depth_str to "".
FP("heap_tree=%s\n", ( Peak == snapshot->kind ? "peak" : "detailed" ));
pp_snapshot_SXPt(fd, snapshot->alloc_sxpt, 0, depth_str,
depth_str_len, snapshot->heap_szB,
snapshot_total_szB);
VG_(free)(depth_str);
} else {
FP("heap_tree=empty\n");
}
}
static void write_snapshots_to_file(void)
{
Int i, fd;
SysRes sres;
sres = VG_(open)(massif_out_file, VKI_O_CREAT|VKI_O_TRUNC|VKI_O_WRONLY,
VKI_S_IRUSR|VKI_S_IWUSR);
if (sres.isError) {
// If the file can't be opened for whatever reason (conflict
// between multiple cachegrinded processes?), give up now.
VG_(message)(Vg_UserMsg,
"error: can't open output file '%s'", massif_out_file );
VG_(message)(Vg_UserMsg,
" ... so profiling results will be missing.");
return;
} else {
fd = sres.res;
}
// Print massif-specific options that were used.
// XXX: is it worth having a "desc:" line? Could just call it "options:"
// -- this file format isn't as generic as Cachegrind's, so the
// implied genericity of "desc:" is bogus.
FP("desc:");
for (i = 0; i < VG_(sizeXA)(args_for_massif); i++) {
Char* arg = *(Char**)VG_(indexXA)(args_for_massif, i);
FP(" %s", arg);
}
if (0 == i) FP(" (none)");
FP("\n");
// Print "cmd:" line.
FP("cmd: ");
if (VG_(args_the_exename)) {
FP("%s", VG_(args_the_exename));
for (i = 0; i < VG_(sizeXA)( VG_(args_for_client) ); i++) {
HChar* arg = * (HChar**) VG_(indexXA)( VG_(args_for_client), i );
if (arg)
FP(" %s", arg);
}
} else {
FP(" ???");
}
FP("\n");
FP("time_unit: %s\n", TimeUnit_to_string(clo_time_unit));
for (i = 0; i < next_snapshot_i; i++) {
Snapshot* snapshot = & snapshots[i];
pp_snapshot(fd, snapshot, i); // Detailed snapshot!
}
}
//------------------------------------------------------------//
//--- Finalisation ---//
//------------------------------------------------------------//
static void ms_fini(Int exit_status)
{
// Output.
write_snapshots_to_file();
// Stats
tl_assert(n_xpts > 0); // always have alloc_xpt
VERB(1, "heap allocs: %u", n_heap_allocs);
VERB(1, "heap reallocs: %u", n_heap_reallocs);
VERB(1, "heap frees: %u", n_heap_frees);
VERB(1, "stack allocs: %u", n_stack_allocs);
VERB(1, "stack frees: %u", n_stack_frees);
VERB(1, "XPts: %u", n_xpts);
VERB(1, "top-XPts: %u (%d%%)",
alloc_xpt->n_children,
( n_xpts ? alloc_xpt->n_children * 100 / n_xpts : 0));
VERB(1, "XPt-init-expansions: %u", n_xpt_init_expansions);
VERB(1, "XPt-later-expansions: %u", n_xpt_later_expansions);
VERB(1, "SXPt allocs: %u", n_sxpt_allocs);
VERB(1, "SXPt frees: %u", n_sxpt_frees);
VERB(1, "skipped snapshots: %u", n_skipped_snapshots);
VERB(1, "real snapshots: %u", n_real_snapshots);
VERB(1, "detailed snapshots: %u", n_detailed_snapshots);
VERB(1, "peak snapshots: %u", n_peak_snapshots);
VERB(1, "cullings: %u", n_cullings);
VERB(1, "XCon_redos: %u", n_XCon_redos);
}
//------------------------------------------------------------//
//--- Initialisation ---//
//------------------------------------------------------------//
static void ms_post_clo_init(void)
{
Int i;
// Check options.
if (clo_heap_admin < 0 || clo_heap_admin > 1024) {
VG_(message)(Vg_UserMsg, "--heap-admin must be between 0 and 1024");
VG_(err_bad_option)("--heap-admin");
}
if (clo_depth < 1 || clo_depth > MAX_DEPTH) {
VG_(message)(Vg_UserMsg, "--depth must be between 1 and %d", MAX_DEPTH);
VG_(err_bad_option)("--depth");
}
if (clo_threshold < 0 || clo_threshold > 10000) {
VG_(message)(Vg_UserMsg, "--threshold must be between 0 and 10000");
VG_(err_bad_option)("--threshold");
}
if (clo_detailed_freq < 1 || clo_detailed_freq > 10000) {
VG_(message)(Vg_UserMsg, "--detailed-freq must be between 1 and 10000");
VG_(err_bad_option)("--detailed-freq");
}
if (clo_max_snapshots < 10 || clo_max_snapshots > 1000) {
VG_(message)(Vg_UserMsg, "--max-snapshots must be between 10 and 1000");
VG_(err_bad_option)("--max-snapshots");
}
// If we have --heap=no, set --heap-admin to zero, just to make sure we
// don't accidentally use a non-zero heap-admin size somewhere.
if (!clo_heap) {
clo_heap_admin = 0;
}
// Print alloc-fns, if necessary.
if (VG_(clo_verbosity) > 1) {
VERB(1, "alloc-fns:");
for (i = 0; i < VG_(sizeXA)(alloc_fns); i++) {
Char** alloc_fn_ptr = VG_(indexXA)(alloc_fns, i);
VERB(1, " %d: %s", i, *alloc_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 );
}
// Initialise snapshot array, and sanity-check it.
snapshots = VG_(malloc)(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();
}
static void ms_pre_clo_init(void)
{
VG_(details_name) ("Massif");
VG_(details_version) (NULL);
VG_(details_description) ("a space profiler");
VG_(details_copyright_author)(
"Copyright (C) 2003-2007, and GNU GPL'd, by Nicholas Nethercote");
VG_(details_bug_reports_to) (VG_BUGS_TO);
// Basic functions
VG_(basic_tool_funcs) (ms_post_clo_init,
ms_instrument,
ms_fini);
// Needs
VG_(needs_libc_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_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,
0 );
// HP_Chunks
malloc_list = VG_(HT_construct)( "Massif's malloc list" );
// Dummy node at top of the context structure.
alloc_xpt = new_XPt(/*ip*/0, /*parent*/NULL);
// Initialise alloc_fns.
init_alloc_fns();
// Initialise args_for_massif.
args_for_massif = VG_(newXA)(VG_(malloc), VG_(free), sizeof(HChar*));
tl_assert( VG_(get_startup_wd)(base_dir, VKI_PATH_MAX) );
}
VG_DETERMINE_INTERFACE_VERSION(ms_pre_clo_init)
//--------------------------------------------------------------------//
//--- end ---//
//--------------------------------------------------------------------//