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ftmemsim-valgrind/massif/ms_main.c
Philippe Waroquiers ceaa5b2efe This patch implements the support needed for stacktraces 
showing inlined function calls.
See 278972 valgrind stacktraces and suppression do not handle inlined function call debuginfo

Reading the inlined dwarf call info is activated using the new clo
  --read-inline-info=yes
Default is currently no but an objective is to optimise the performance
and memory in order to possibly set it on by default.
(see below discussion about performances).

Basically, the patch provides the following pieces:
1. Implement a new dwarf3 reader that reads the inlined call info
2. Some performance improvements done for this new parser, and
   on some common code between the new parser and the var info parser.
3. Use the parsed inlined info to produce stacktrace showing inlined calls
4. Use the parsed inlined info in the suppression matching and suppression generation
5. and of course, some reg tests

1. new dwarf3 reader:
---------------------
Two options were possible: add the reading of the inlined info
in the current var info dwarf reader, or add a 2nd reader.
The 2nd approach was preferred, for the following reasons:
The var info reader is slow, memory hungry and quite complex.
Having a separate parsing phase for the inlined information
is simpler/faster when just reading the inlined info.
Possibly, a single parser would be faster when using both
--read-var-info=yes and --read-inline-info=yes.
However, var-info being extremely memory/cpu hungry, it is unlikely
to be used often, and having a separate parsing for inlined info
does in any case make not much difference.
(--read-var-info=yes is also now less interesting thanks to commit
r13991, which provides a fast and low memory "reasonable" location
for an address).

The inlined info parser reads the dwarf info to make calls
to priv_storage.h ML_(addInlInfo).

2. performance optimisations
----------------------------
* the abbrev cache has been improved in revision r14035.
* The new parser skips the non interesting DIEs
  (the var-info parser has no logic to skip uninteresting DIEs).
* Some other minor perf optimisation here and there.
In total now, on a big executable, 15 seconds CPU are needed to
create the inlined info (on my slow x86 pentium).

With regards to memory, the dinfo arena:
with inlined info: 172281856/121085952  max/curr mmap'd
without          : 157892608/106721280  max/curr mmap'd,
So, basically, inlined information costs about 15Mb of memory for
my big executable (compared to first version of the patch, this is
already using less memory, thanks to the strpool deduppoolalloc.
The needed memory can probably be decreased somewhat more.

3. produce better stack traces
------------------------------
VG_(describe_IP) has a new argument InlIPCursor *iipc which allows
to describe inlined function calls by doing repetitive calls 
to describe_IP. See pub_tool_debuginfo.h for a description.

4. suppression generation and matching
--------------------------------------
* suppression generation now also uses an InlIPCursor *iipc
  to generate a line for each inlined fn call.

* suppression matching: to allow suppression matching to
match one IP to several function calls in a suppression entry,
the 'inputCompleter' object (that allows to lazily generate
function or object names for a stacktrace when matching 
an error with a suppression) has been generalised a little bit
more to also lazily generate the input sequence.
VG_(generic_match) has been updated so as to be more generic
with respect to the input completer : when providing an
input completer, VG_(generic_match) does not need anymore
to produce/compute any input itself : this is all delegated
to the input completer.

5. various regtests
-------------------
to test stack traces with inlined calls, and suppressions
of (some of) these errors using inlined fn calls matching.


Work still to do:
-----------------
* improve parsing performance
* improve the memory overhead.
* handling the directory name for files of the inlined function calls is not yet done.
  (probably implies to refactor some code)
* see if m_errormgr.c *offsets arrays cannot be managed via xarray



git-svn-id: svn://svn.valgrind.org/valgrind/trunk@14036
2014-06-15 15:42:20 +00:00

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//--------------------------------------------------------------------*/
//--- 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) 2003-2013 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 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
// - 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%.]
//
// - 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:
// - 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_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_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 a tree representing 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 (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_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 ---//
//------------------------------------------------------------//
// 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*));
}
// Determines if the named function is a member of the XArray.
static Bool is_member_fn(XArray* fns, const HChar* fnname)
{
HChar** 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)(fns); i++) {
fn_ptr = VG_(indexXA)(fns, i);
if (VG_STREQ(fnname, *fn_ptr))
return True;
}
return False;
}
//------------------------------------------------------------//
//--- 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"
);
}
//------------------------------------------------------------//
//--- 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
//
// (Note that malformed stack traces can lead to difficulties. See the
// comment at the bottom of get_XCon.)
//
// 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;
static XPt* new_XPt(Addr ip, XPt* parent)
{
// XPts are never freed, so we can use VG_(perm_malloc) to allocate them.
// Note that we cannot use VG_(perm_malloc) for the 'children' array, because
// that needs to be resizable.
XPt* xpt = VG_(perm_malloc)(sizeof(XPt), vg_alignof(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 (0 == parent->max_children) {
parent->max_children = 4;
parent->children = VG_(malloc)( "ms.main.acx.1",
parent->max_children * sizeof(XPt*) );
n_xpt_init_expansions++;
} else {
parent->max_children *= 2; // Double size
parent->children = VG_(realloc)( "ms.main.acx.2",
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(const void* n1, const void* n2)
{
const SXPt* sxpt1 = *(const SXPt *const *)n1;
const SXPt* sxpt2 = *(const SXPt *const *)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 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 (0 == total_szB && 0 != clo_threshold) {
sig_child_threshold_szB = 1;
} else {
sig_child_threshold_szB = (SizeT)((total_szB * clo_threshold) / 100);
}
// 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)("ms.main.dX.1", 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, insig_children_szB = 0;
sxpt->Sig.children = VG_(malloc)("ms.main.dX.2",
n_child_sxpts * sizeof(SXPt*));
// Duplicate the significant children. (Nb: sig_children_szB +
// insig_children_szB doesn't necessarily equal xpt->szB.)
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;
} else {
insig_children_szB += xpt->children[i]->szB;
}
}
// Create the SXPt for the insignificant children, if any, and put it
// in the last child entry.
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)("ms.main.dX.3", 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)
{
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);
// Unfortunately, xpt's size is not necessarily equal to the sum of xpt's
// children's sizes. See comment at the bottom of get_XCon.
}
// 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) {
for (i = 0; i < sxpt->Sig.n_children; i++) {
sanity_check_SXTree(sxpt->Sig.children[i]);
}
}
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)
// This is used for various buffers which can hold function names/IP
// description. Some C++ names can get really long so 1024 isn't big
// enough.
#define BUF_LEN 2048
// Determine if the given IP belongs to a function that should be ignored.
static Bool fn_should_be_ignored(Addr ip)
{
static HChar buf[BUF_LEN];
return
( VG_(get_fnname)(ip, buf, BUF_LEN) && is_member_fn(ignore_fns, buf)
? True : False );
}
// 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 exclude_first_entry, Addr ips[])
{
static HChar 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,
NULL/*array to dump SP values in*/,
NULL/*array to dump FP values in*/,
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; }
// Filter out alloc fns. If requested, we automatically remove the
// first entry (which presumably will be something like malloc or
// __builtin_new that we're sure to filter out) without looking at it,
// because VG_(get_fnname) is expensive.
n_alloc_fns_removed = ( exclude_first_entry ? 1 : 0 );
for (i = n_alloc_fns_removed; i < n_ips; i++) {
if (VG_(get_fnname)(ips[i], buf, BUF_LEN)) {
if (is_member_fn(alloc_fns, 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.
// Unless the allocation should be ignored, in which case we return NULL.
static XPt* get_XCon( ThreadId tid, Bool exclude_first_entry )
{
static 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, exclude_first_entry, ips);
// Should we ignore this allocation? (Nb: n_ips can be zero, eg. if
// 'main' is marked as an alloc-fn.)
if (n_ips > 0 && fn_should_be_ignored(ips[0])) {
return NULL;
}
// 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;
}
}
}
// [Note: several comments refer to this comment. Do not delete it
// without updating them.]
//
// A complication... If all stack traces were well-formed, then the
// returned xpt would always be a bottom-XPt. As a consequence, an XPt's
// size would always be equal to the sum of its children's sizes, which
// is an excellent sanity check.
//
// Unfortunately, stack traces occasionally are malformed, ie. truncated.
// This allows a stack trace to be a sub-trace of another, eg. a/b/c is a
// sub-trace of a/b/c/d. So we can't assume this xpt is a bottom-XPt;
// nor can we do sanity check an XPt's size against its children's sizes.
// This is annoying, but must be dealt with. (Older versions of Massif
// had this assertion in, and it was reported to fail by real users a
// couple of times.) Even more annoyingly, I can't come up with a simple
// test case that exhibit such a malformed stack trace, so I can't
// regression test it. Sigh.
//
// However, we can print a warning, so that if it happens (unexpectedly)
// in existing regression tests we'll know. Also, it warns users that
// the output snapshots may not add up the way they might expect.
//
//tl_assert(0 == xpt->n_children); // Must be bottom-XPt
if (0 != xpt->n_children) {
static Int n_moans = 0;
if (n_moans < 3) {
VG_(umsg)(
"Warning: Malformed stack trace detected. In Massif's output,\n");
VG_(umsg)(
" the size of an entry's child entries may not sum up\n");
VG_(umsg)(
" to the entry's size as they normally do.\n");
n_moans++;
if (3 == n_moans)
VG_(umsg)(
" (And Massif now won't warn about this again.)\n");
}
}
return xpt;
}
// Update 'szB' of every XPt in the XCon, by percolating upwards.
static void update_XCon(XPt* xpt, SSizeT space_delta)
{
tl_assert(clo_heap);
tl_assert(NULL != 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 i or 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, 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:%ld, ex:%ld, st:%ld)\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];
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) {
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 = 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 )
{
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* 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_(malloc)("ms.main.rb.1", 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, "<<< record_block (%lu, %lu)\n", req_szB, slop_szB);
hc->where = get_XCon( tid, exclude_first_entry );
if (hc->where) {
// Update statistics.
n_heap_allocs++;
// Update heap stats.
update_heap_stats(req_szB, clo_heap_admin + slop_szB);
// Update XTree.
update_XCon(hc->where, req_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_(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 )
{
// 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 (hc->where) {
// 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.
update_XCon(hc->where, -hc->req_szB);
// 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_(free)( 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.
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;
XPt *old_where, *new_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 (hc->where) {
// 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_(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, /*exclude_first_entry*/True);
if (!is_ignored && new_where) {
hc->where = new_where;
update_XCon(old_where, -old_req_szB);
update_XCon(new_where, new_req_szB);
} else {
// The realloc itself is ignored.
is_ignored = True;
// 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",
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 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);
VG_(cli_free)(p);
}
static void ms___builtin_delete ( ThreadId tid, void* p )
{
unrecord_block(p, /*maybe_snapshot*/True);
VG_(cli_free)(p);
}
static void ms___builtin_vec_delete ( ThreadId tid, void* p )
{
unrecord_block(p, /*maybe_snapshot*/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);
for (end = a + len - VKI_PAGE_SIZE; a < end; a += VKI_PAGE_SIZE) {
unrecord_block((void*)a, /*maybe_snapshot*/False);
}
unrecord_block((void*)a, /*maybe_snapshot*/True);
}
//------------------------------------------------------------//
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 (%ld)\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 (%ld)\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");
VG_(gdb_printf) ("massif monitor commands:\n");
VG_(gdb_printf) (" snapshot [<filename>]\n");
VG_(gdb_printf) (" detailed_snapshot [<filename>]\n");
VG_(gdb_printf) (" takes a snapshot (or a detailed snapshot)\n");
VG_(gdb_printf) (" and saves it in <filename>\n");
VG_(gdb_printf) (" default <filename> is massif.vgdb.out\n");
VG_(gdb_printf) ("\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);
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);
*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,
VexGuestLayout* layout,
VexGuestExtents* vge,
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 ---//
//------------------------------------------------------------//
HChar FP_buf[BUF_LEN];
// 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, BUF_LEN, format, ##args); \
FP_buf[BUF_LEN-1] = '\0'; /* Make sure the string is terminated. */ \
VG_(write)(fd, (void*)FP_buf, VG_(strlen)(FP_buf)); \
})
// Nb: uses a static buffer, each call trashes the last string returned.
static const HChar* make_perc(double x)
{
static HChar mbuf[32];
VG_(percentify)((ULong)(x * 100), 10000, 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, HChar* depth_str,
Int depth_str_len,
SizeT snapshot_heap_szB, SizeT snapshot_total_szB)
{
Int i, j, n_insig_children_sxpts;
SXPt* child = NULL;
// Used for printing function names. Is made static to keep it out
// of the stack frame -- this function is recursive. Obviously this
// now means its contents are trashed across the recursive call.
static HChar ip_desc_array[BUF_LEN];
const HChar* ip_desc = ip_desc_array;
switch (sxpt->tag) {
case SigSXPt:
// Print the SXPt itself.
if (0 == depth) {
if (clo_heap) {
ip_desc =
( clo_pages_as_heap
? "(page allocation syscalls) mmap/mremap/brk, --alloc-fns, etc."
: "(heap allocation functions) malloc/new/new[], --alloc-fns, etc."
);
} else {
// XXX: --alloc-fns?
// Nick thinks this case cannot happen. ip_desc_array would be
// conceptually uninitialised here. Therefore:
tl_assert2(0, "pp_snapshot_SXPt: unexpected");
}
} else {
// If it's main-or-below-main, we (if appropriate) ignore everything
// below it by pretending it has no children.
if ( ! VG_(clo_show_below_main) ) {
Vg_FnNameKind kind = VG_(get_fnname_kind_from_IP)(sxpt->Sig.ip);
if (Vg_FnNameMain == kind || Vg_FnNameBelowMain == kind) {
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_array, BUF_LEN, NULL);
}
// Do the non-ip_desc part first...
FP("%sn%d: %lu ", depth_str, sxpt->Sig.n_children, sxpt->szB);
// For ip_descs beginning with "0xABCD...:" addresses, we first
// measure the length of the "0xabcd: " address at the start of the
// ip_desc.
j = 0;
if ('0' == ip_desc[0] && 'x' == ip_desc[1]) {
j = 2;
while (True) {
if (ip_desc[j]) {
if (':' == ip_desc[j]) break;
j++;
} else {
tl_assert2(0, "ip_desc has unexpected form: %s\n", ip_desc);
}
}
}
// Nb: We treat this specially (ie. we don't use FP) so that if the
// ip_desc is too long (eg. due to a long C++ function name), it'll
// get truncated, but the '\n' is still there so its a valid file.
// (At one point we were truncating without adding the '\n', which
// caused bug #155929.)
//
// Also, we account for the length of the address in ip_desc when
// truncating. (The longest address we could have is 18 chars: "0x"
// plus 16 address digits.) This ensures that the truncated function
// name always has the same length, which makes truncation
// deterministic and thus makes testing easier.
tl_assert(j <= 18);
VG_(snprintf)(FP_buf, BUF_LEN, "%s\n", ip_desc);
FP_buf[BUF_LEN-18+j-5] = '.'; // "..." at the end make the
FP_buf[BUF_LEN-18+j-4] = '.'; // truncation more obvious.
FP_buf[BUF_LEN-18+j-3] = '.';
FP_buf[BUF_LEN-18+j-2] = '\n'; // The last char is '\n'.
FP_buf[BUF_LEN-18+j-1] = '\0'; // The string is terminated.
VG_(write)(fd, (void*)FP_buf, VG_(strlen)(FP_buf));
// 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++) {
child = sxpt->Sig.children[i];
if (InsigSXPt == child->tag)
n_insig_children_sxpts++;
// Ok, print the child. NB: contents of ip_desc_array will be
// trashed by this recursive call. Doesn't matter currently,
// but worth noting.
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: {
const HChar* s = ( 1 == sxpt->Insig.n_xpts ? "," : "s, all" );
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));
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;
HChar* depth_str = VG_(malloc)("ms.main.pps.1",
sizeof(HChar) * 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(const HChar* massif_out_file,
Snapshot snapshots_array[],
Int nr_elements)
{
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 (sr_isError(sres)) {
// If the file can't be opened for whatever reason (conflict
// between multiple cachegrinded processes?), give up now.
VG_(umsg)("error: can't open output file '%s'\n", massif_out_file );
VG_(umsg)(" ... so profiling results will be missing.\n");
return;
} else {
fd = sr_Res(sres);
}
// 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++) {
HChar* arg = *(HChar**)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 < nr_elements; i++) {
Snapshot* snapshot = & snapshots_array[i];
pp_snapshot(fd, snapshot, i); // Detailed snapshot!
}
VG_(close) (fd);
}
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 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",
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;
}
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("stack frees: %u\n", n_stack_frees);
STATS("XPts: %u\n", n_xpts);
STATS("top-XPts: %u (%d%%)\n",
alloc_xpt->n_children,
( n_xpts ? alloc_xpt->n_children * 100 / n_xpts : 0));
STATS("XPt init expansions: %u\n", n_xpt_init_expansions);
STATS("XPt later expansions: %u\n", n_xpt_later_expansions);
STATS("SXPt allocs: %u\n", n_sxpt_allocs);
STATS("SXPt frees: %u\n", n_sxpt_frees);
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);
STATS("XCon redos: %u\n", n_XCon_redos);
#undef STATS
}
//------------------------------------------------------------//
//--- Finalisation ---//
//------------------------------------------------------------//
static void ms_fini(Int exit_status)
{
// Output.
write_snapshots_array_to_file();
// Stats
tl_assert(n_xpts > 0); // always have alloc_xpt
if (VG_(clo_stats))
ms_print_stats();
}
//------------------------------------------------------------//
//--- Initialisation ---//
//------------------------------------------------------------//
static void ms_post_clo_init(void)
{
Int i;
HChar* LD_PRELOAD_val;
HChar* s;
HChar* s2;
// Check options.
if (clo_pages_as_heap) {
if (clo_stacks) {
VG_(fmsg_bad_option)(
"--pages-as-heap=yes 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). We replace it entirely with spaces because then
// the linker doesn't complain (it does complain if we just change the name
// to a bogus file). 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) {
clo_heap_admin = 0; // No heap admin on pages.
LD_PRELOAD_val = VG_(getenv)( VG_(LD_PRELOAD_var_name) );
tl_assert(LD_PRELOAD_val);
// Make sure the vgpreload_core-$PLATFORM entry is there, for sanity.
s2 = VG_(strstr)(LD_PRELOAD_val, "vgpreload_core");
tl_assert(s2);
// Now find the vgpreload_massif-$PLATFORM entry.
s2 = VG_(strstr)(LD_PRELOAD_val, "vgpreload_massif");
tl_assert(s2);
// Blank out everything to the previous ':', which must be there because
// of the preceding vgpreload_core-$PLATFORM entry.
for (s = s2; *s != ':'; s--) {
*s = ' ';
}
// Blank out everything to the end of the entry, which will be '\0' if
// LD_PRELOAD was empty before Valgrind started, or ':' otherwise.
for (s = s2; *s != ':' && *s != '\0'; s++) {
*s = ' ';
}
}
// 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();
}
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) 2003-2013, 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
= 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_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.
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 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 ---//
//--------------------------------------------------------------------//
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