From 0f10b973f1fba02269207354322f1f9a313c8528 Mon Sep 17 00:00:00 2001 From: Florian Krohm Date: Mon, 6 Apr 2015 21:34:30 +0000 Subject: [PATCH] Followup to r14898 which changes the storage of segment names by putting them into a string table. This patch adds reference counting to segment names and frees them when they are no longer used. The so freed memory can be reclaimed to store future segment names. New file coregrind/m_aspacemgr/aspacemgr-segnames.c which has all the code dealing with segment names. Carved out of aspacemgr-linux.c Detailled comments in the code. Fixes BZ 344559. git-svn-id: svn://svn.valgrind.org/valgrind/trunk@15073 --- NEWS | 1 + coregrind/Makefile.am | 1 + coregrind/m_aspacemgr/aspacemgr-linux.c | 131 ++---- coregrind/m_aspacemgr/aspacemgr-segnames.c | 440 +++++++++++++++++++++ coregrind/m_aspacemgr/priv_aspacemgr.h | 23 ++ 5 files changed, 491 insertions(+), 105 deletions(-) create mode 100644 coregrind/m_aspacemgr/aspacemgr-segnames.c diff --git a/NEWS b/NEWS index 4185bcd279..1b01dc09a7 100644 --- a/NEWS +++ b/NEWS @@ -140,6 +140,7 @@ where XXXXXX is the bug number as listed below. obvious and non-obvious issues 344512 Fix unhandled syscall: unix:348 (__pthread_chdir) and unhandled syscall: unix:349 (__pthread_fchdir) on OS X +344559 Garbage collection of unused segment names in address space manager 344560 Fix stack traces missing penultimate frame on OS X 344621 Fix memcheck/tests/err_disable4 test on OS X 344686 Fix suppression for pthread_rwlock_init on OS X 10.10 diff --git a/coregrind/Makefile.am b/coregrind/Makefile.am index d07be737b1..1532b538c9 100644 --- a/coregrind/Makefile.am +++ b/coregrind/Makefile.am @@ -312,6 +312,7 @@ COREGRIND_SOURCES_COMMON = \ m_aspacehl.c \ m_aspacemgr/aspacemgr-common.c \ m_aspacemgr/aspacemgr-linux.c \ + m_aspacemgr/aspacemgr-segnames.c \ m_coredump/coredump-elf.c \ m_coredump/coredump-macho.c \ m_debuginfo/misc.c \ diff --git a/coregrind/m_aspacemgr/aspacemgr-linux.c b/coregrind/m_aspacemgr/aspacemgr-linux.c index c996908545..48bd2b3341 100644 --- a/coregrind/m_aspacemgr/aspacemgr-linux.c +++ b/coregrind/m_aspacemgr/aspacemgr-linux.c @@ -280,27 +280,6 @@ # define VG_N_SEGMENTS 30000 #endif -/* Max number of segment file names we can track. These are big (1002 - bytes) so on Android limit the space usage to ~1MB. */ -#if defined(VGPV_arm_linux_android) \ - || defined(VGPV_x86_linux_android) \ - || defined(VGPV_mips32_linux_android) \ - || defined(VGPV_arm64_linux_android) -# define VG_N_SEGNAMES 1000 -#else -# define VG_N_SEGNAMES 6000 -#endif - -/* Max length of a segment file name. FIXME: to be removed */ -#define VG_MAX_SEGNAMELEN 1000 - -/* String table for segment names */ - -/* FIXME: This is just for backward compatibility for now. To be adjusted. */ -static HChar segnames[VG_N_SEGNAMES * VG_MAX_SEGNAMELEN]; -static SizeT segnames_used = 0; /* number of characters used */ -static UInt num_segnames = 0; /* number of names in string table */ - /* Array [0 .. nsegments_used-1] of all mappings. */ /* Sorted by .addr field. */ /* I: len may not be zero. */ @@ -379,48 +358,6 @@ static void parse_procselfmaps ( #endif -/*-----------------------------------------------------------------*/ -/*--- ---*/ -/*--- Segment name management. ---*/ -/*--- ---*/ -/*-----------------------------------------------------------------*/ - -/* Searches the string table to find an index for the given name. - If none is found, an index is allocated and the name stored. - If the string is too long to store, return -1. -*/ -static Int allocate_segname ( const HChar* name ) -{ - SizeT len, l, ix; - - aspacem_assert(name); - - if (0) VG_(debugLog)(0,"aspacem","allocate_segname %s\n", name); - - len = VG_(strlen)(name); - - /* first see if we already have the name. */ - for (ix = 0; ix < segnames_used; ix += l + 1) { - l = VG_(strlen)(segnames + ix); - if (l == len && VG_(strcmp)(name, segnames + ix) == 0) return ix; - } - - /* Is there enough room in the string table? */ - if (len + 1 > (sizeof segnames) - segnames_used) { - return -1; - } - - ++num_segnames; - - /* copy it in */ - ix = segnames_used; - - VG_(strcpy)(segnames + segnames_used, name); - segnames_used += len + 1; - - return ix; -} - /*-----------------------------------------------------------------*/ /*--- ---*/ @@ -479,33 +416,15 @@ static void show_len_concisely ( /*OUT*/HChar* buf, Addr start, Addr end ) ML_(am_sprintf)(buf, fmt, len); } -/* Returns a sequence number for the fnIdx position in segnames. - Used in aspacemgr debug output to associate a segment with - the list of segments output at the beginning. */ -static Int fnIdx_seqnr(Int fnIdx) -{ - SizeT ix; - Int seqnr = -1; - - for (ix = 0; ix < segnames_used; ix += VG_(strlen)(segnames + ix) + 1) { - seqnr++; - if (ix == fnIdx) - return seqnr; - } - - return -1; -} - /* Show full details of an NSegment */ static void show_nsegment_full ( Int logLevel, Int segNo, const NSegment* seg ) { HChar len_buf[20]; - const HChar* name = "(none)"; + const HChar* name = VG_(am_get_segname)( seg->fnIdx ); - if (seg->fnIdx >= 0 && seg->fnIdx < segnames_used - && segnames[seg->fnIdx] != 0) - name = segnames + seg->fnIdx; + if (name == NULL) + name = "(none)"; show_len_concisely(len_buf, seg->start, seg->end); @@ -520,7 +439,7 @@ static void show_nsegment_full ( Int logLevel, Int segNo, const NSegment* seg ) seg->isCH ? 'H' : '-', show_ShrinkMode(seg->smode), seg->dev, seg->ino, seg->offset, - fnIdx_seqnr(seg->fnIdx), seg->fnIdx, + VG_(am_segname_get_seqnr)(seg->fnIdx), seg->fnIdx, name ); } @@ -567,7 +486,7 @@ static void show_nsegment ( Int logLevel, Int segNo, const NSegment* seg ) seg->hasX ? 'x' : '-', seg->hasT ? 'T' : '-', seg->isCH ? 'H' : '-', seg->dev, seg->ino, seg->offset, - fnIdx_seqnr(seg->fnIdx), seg->fnIdx + VG_(am_segname_get_seqnr)(seg->fnIdx), seg->fnIdx ); break; @@ -598,15 +517,10 @@ static void show_nsegment ( Int logLevel, Int segNo, const NSegment* seg ) void VG_(am_show_nsegments) ( Int logLevel, const HChar* who ) { Int i; - SizeT ix; VG_(debugLog)(logLevel, "aspacem", - "<<< SHOW_SEGMENTS: %s (%d segments, %u segnames)\n", - who, nsegments_used, num_segnames); - i = 0; - for (ix = 0; ix < segnames_used; ix += VG_(strlen)(segnames + ix) + 1) { - VG_(debugLog)(logLevel, "aspacem", - "(%d,%lu) %s\n", i++, ix, segnames + ix); - } + "<<< SHOW_SEGMENTS: %s (%d segments)\n", + who, nsegments_used); + VG_(am_show_segnames)( logLevel, who); for (i = 0; i < nsegments_used; i++) show_nsegment( logLevel, i, &nsegments[i] ); VG_(debugLog)(logLevel, "aspacem", @@ -618,10 +532,8 @@ void VG_(am_show_nsegments) ( Int logLevel, const HChar* who ) has one. */ const HChar* VG_(am_get_filename)( NSegment const * seg ) { - Int i; aspacem_assert(seg); - i = seg->fnIdx; - return (i < 0) ? NULL : segnames + i; + return VG_(am_get_segname)( seg->fnIdx ); } /* Collect up the start addresses of segments whose kind matches one of @@ -709,8 +621,7 @@ static Bool sane_NSegment ( const NSegment* s ) case SkFileC: case SkFileV: return s->smode == SmFixed - && (s->fnIdx == -1 || - (s->fnIdx >= 0 && s->fnIdx < segnames_used)) + && VG_(am_sane_segname)(s->fnIdx) && !s->isCH; case SkResvn: @@ -764,6 +675,7 @@ static Bool maybe_merge_nsegments ( NSegment* s1, const NSegment* s2 ) + ((ULong)s2->start) - ((ULong)s1->start) ) { s1->end = s2->end; s1->hasT |= s2->hasT; + VG_(am_dec_refcount)(s1->fnIdx); return True; } break; @@ -1441,6 +1353,8 @@ static void split_nsegment_at ( Addr a ) nsegments[i+1].offset += ((ULong)nsegments[i+1].start) - ((ULong)nsegments[i].start); + VG_(am_inc_refcount)(nsegments[i].fnIdx); + aspacem_assert(sane_NSegment(&nsegments[i])); aspacem_assert(sane_NSegment(&nsegments[i+1])); } @@ -1500,7 +1414,11 @@ static void add_segment ( const NSegment* seg ) /* Now iLo .. iHi inclusive is the range of segment indices which seg will replace. If we're replacing more than one segment, - slide those above the range down to fill the hole. */ + slide those above the range down to fill the hole. Before doing + that decrement the reference counters for the segments names of + the replaced segments. */ + for (i = iLo; i <= iHi; ++i) + VG_(am_dec_refcount)(nsegments[i].fnIdx); delta = iHi - iLo; aspacem_assert(delta >= 0); if (delta > 0) { @@ -1597,7 +1515,7 @@ static void read_maps_callback ( Addr addr, SizeT len, UInt prot, # endif // defined(VGP_arm_linux) if (filename) - seg.fnIdx = allocate_segname( filename ); + seg.fnIdx = VG_(am_allocate_segname)( filename ); if (0) show_nsegment( 2,0, &seg ); add_segment( &seg ); @@ -1638,6 +1556,9 @@ Addr VG_(am_startup) ( Addr sp_at_startup ) aspacem_assert(sizeof(SizeT) == sizeof(void*)); aspacem_assert(sizeof(SSizeT) == sizeof(void*)); + /* Initialise the string table for segment names. */ + VG_(am_segnames_init)(); + /* Check that we can store the largest imaginable dev, ino and offset numbers in an NSegment. */ aspacem_assert(sizeof(seg.dev) == 8); @@ -2080,7 +2001,7 @@ VG_(am_notify_client_mmap)( Addr a, SizeT len, UInt prot, UInt flags, seg.mode = mode; } if (ML_(am_resolve_filename)(fd, buf, VKI_PATH_MAX)) { - seg.fnIdx = allocate_segname( buf ); + seg.fnIdx = VG_(am_allocate_segname)( buf ); } } add_segment( &seg ); @@ -2302,9 +2223,9 @@ SysRes VG_(am_mmap_named_file_fixed_client) seg.mode = mode; } if (name) { - seg.fnIdx = allocate_segname( name ); + seg.fnIdx = VG_(am_allocate_segname)( name ); } else if (ML_(am_resolve_filename)(fd, buf, VKI_PATH_MAX)) { - seg.fnIdx = allocate_segname( buf ); + seg.fnIdx = VG_(am_allocate_segname)( buf ); } add_segment( &seg ); @@ -2609,7 +2530,7 @@ static SysRes VG_(am_mmap_file_float_valgrind_flags) ( SizeT length, UInt prot, seg.mode = mode; } if (ML_(am_resolve_filename)(fd, buf, VKI_PATH_MAX)) { - seg.fnIdx = allocate_segname( buf ); + seg.fnIdx = VG_(am_allocate_segname)( buf ); } add_segment( &seg ); diff --git a/coregrind/m_aspacemgr/aspacemgr-segnames.c b/coregrind/m_aspacemgr/aspacemgr-segnames.c new file mode 100644 index 0000000000..481b58ea88 --- /dev/null +++ b/coregrind/m_aspacemgr/aspacemgr-segnames.c @@ -0,0 +1,440 @@ +/* -*- mode: C; c-basic-offset: 3; -*- */ + +/*--------------------------------------------------------------------*/ +/*--- Segment name management aspacemgr-segnames.c ---*/ +/*--------------------------------------------------------------------*/ + +/* + This file is part of Valgrind, a dynamic binary instrumentation + framework. + + Copyright (C) 2015-2015 Florian Krohm + + 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. +*/ + +/* Segment names are stored in a string table. + + The string table is organised into slots of varying length. Slots are + adjacent and there are no holes between slots. + A slot consists of two parts: + + (1) a fixed size overhead of length 4 bytes + (2) a variable size payload of up to 65535 bytes + + The segment name is stored in the payload area. Therefore: + a segment name cannot be longer than 65535 bytes including the '\0' + terminator. This looks like a reasonable limitation. + + Overall slot layout: + + | 4 bytes | max 65535 bytes | + +-----------------------------+-------------------------+ + | overhead | payload | + +-----------------------------+-------------------------+ + ^ ^ + | | + -4 +----- seg->fnIdx + + Each slot is uniquely identified by an index which points to the first + byte of the payload area. It is this value that is stored in seg->fnIdx. + Note, that this value is at least 4. + + A slot either holds a string or it is free. The status of a slot is + identified by the leftmost bit in the overhead field, the so called F-bit. + F-bit == 1 means that slot is free; otherwise it is occupied and holds a + string. + + Slot containing a string (segment name): + + bits | 1 | 15 | 16 | + +---+--------------+----------+-------------------------+ + | 0 | refcount | slotsize | the string including \0 | + +---+--------------+----------+-------------------------+ + ^ ^ ^ + | | | + -4 -2 +----- seg->fnIdx + + Segment names are reference counted. 15 bits are available which allows + for up to 32767 references. If the string is referenced more than 32767 + times, the reference count will be frozen and the slot can never + become free. I'm not unduly concerned. + Two bytes are reserved to hold the size of the slot. Well, it's actually + the size of the payload aread (i.e. the size of the slot minus the + overhead). Ah well -- the name sticks. + With two bytes to store the size, the payload area can be at most 65535 + bytes large. + + A free slot looks like this: + + bits | 1 | 31 | 16 | + +---+-------------------------+----------+--------------+ + | 1 | index of next free slot | slotsize | .. unused .. | + +---+-------------------------+----------+--------------+ + ^ ^ + | | + -4 +----- seg->fnIdx + + Free slots are chained together in a singly linked list. An index of + zero indicates the end of the chain. Note that zero cannot conflict + with an index into the string table as the minumum index is at least + four (see above). + + The typical way to traverse the segment names is: + + for (ix = overhead; (size = get_slotsize(ix)) != 0; ix += size + overhead) { + if (is_freeslot(ix)) + do this + else + do that + } + + Important detail: there is a sentinel at the end of the list, namely a + slot with a zero-sized payload area. + + Whenever a new segment name needs to be stashed away, the list of free + slots is traversed and the first slot which is large enough is being taken + (first fit). There will be no splitting of slots, as that complicates + matters and without slot coalescing would lead to memory fragmentation. + So we leave it as is until a use case comes up that needs something better. +*/ + +#include "pub_core_basics.h" // types +#include "priv_aspacemgr.h" + +// A few constants. +enum { + refcount_size = sizeof(UShort), + slotsize_size = sizeof(UShort), + overhead = refcount_size + slotsize_size, + max_refcount = 0x7fff, // 2 bytes - F-bit + max_slotsize = 0xffff, // 2 bytes + max_slotindex = 0x7fffffff, // 4 bytes - F-bit + fbit_mask = 0x80, + end_of_chain = 0 +}; + +/* The old segname implementation allowed for 1000 names on Android and + 6000 names on other platforms. Each name was allowed to be 1000 characters + long. That was very wasteful. */ +#define VG_TABLE_SIZE 1000000 + +/* String table for segment names */ + +static HChar segnames[VG_TABLE_SIZE]; /* her majesty, the string table */ +static SizeT segnames_used = 0; /* number of bytes used */ +static UInt num_segnames = 0; /* number of names in string table */ +static UInt num_slots = 0; /* number of slots in string table */ +static UInt freeslot_chain = end_of_chain; + +static Bool +is_freeslot(UInt ix) +{ + aspacem_assert(ix >= overhead && ix <= segnames_used); + return (segnames[ix - 4] & fbit_mask) != 0; +} + +static void +put_slotindex(UInt ix, UInt slotindex) +{ + aspacem_assert(ix >= overhead && ix <= segnames_used); + if (slotindex != 0) + aspacem_assert(slotindex >= overhead && slotindex <= segnames_used); + + slotindex |= fbit_mask << 24; + segnames[ix - 1] = slotindex & 0xFF; slotindex >>= 8; + segnames[ix - 2] = slotindex & 0xFF; slotindex >>= 8; + segnames[ix - 3] = slotindex & 0xFF; slotindex >>= 8; + segnames[ix - 4] = slotindex & 0xFF; +} + +static UInt +get_slotindex(UInt ix) +{ + aspacem_assert(ix >= overhead && ix <= segnames_used); + aspacem_assert(is_freeslot(ix)); + + // Avoid unexpected sign extension + const UChar *unames = (const UChar *)segnames; + + UInt slotindex = 0; + slotindex |= unames[ix - 4]; slotindex <<= 8; + slotindex |= unames[ix - 3]; slotindex <<= 8; + slotindex |= unames[ix - 2]; slotindex <<= 8; + slotindex |= unames[ix - 1]; + + return slotindex & max_slotindex; // removes the F-bit +} + +static void +put_slotsize(UInt ix, UInt size) +{ + aspacem_assert(ix >= overhead && ix <= segnames_used); + aspacem_assert(size <= max_slotsize); + segnames[ix - 1] = size & 0xff; + segnames[ix - 2] = size >> 8; +} + +static UInt +get_slotsize(UInt ix) +{ + aspacem_assert(ix >= overhead && ix <= segnames_used); + + // Avoid unexpected sign extension + const UChar *unames = (const UChar *)segnames; + if (is_freeslot(ix)) + return (unames[ix] << 8) | unames[ix+1]; + else + return (unames[ix - 2] << 8) | unames[ix - 1]; +} + +static void +put_refcount(UInt ix, UInt rc) +{ + aspacem_assert(ix >= overhead && ix <= segnames_used); + aspacem_assert(rc <= max_refcount); + // rc <= max_refcount ensures that the F-bit is zero + segnames[ix - 3] = rc & 0xff; + segnames[ix - 4] = rc >> 8; +} + +static UInt +get_refcount(UInt ix) +{ + aspacem_assert(ix >= overhead && ix <= segnames_used); + // must not be a free slot + aspacem_assert(! is_freeslot(ix)); + + // Avoid unexpected sign extension + const UChar *unames = (const UChar *)segnames; + return (unames[ix - 4] << 8) | unames[ix - 3]; +} + +static void +inc_refcount(UInt ix) +{ + aspacem_assert(ix >= overhead && ix <= segnames_used); + UInt rc = get_refcount(ix); + if (rc != max_refcount) + put_refcount(ix, rc + 1); +} + +static void +dec_refcount(UInt ix) +{ + aspacem_assert(ix >= overhead && ix <= segnames_used); + UInt rc = get_refcount(ix); + aspacem_assert(rc > 0); + if (rc != max_refcount) { + --rc; + if (rc != 0) { + put_refcount(ix, rc); + } else { + UInt size = get_slotsize(ix); + /* Chain this slot in the freelist */ + put_slotindex(ix, freeslot_chain); + get_slotindex(ix); + put_slotsize(ix + slotsize_size, size); + get_slotindex(ix); + freeslot_chain = ix; + --num_segnames; + if (0) VG_(am_show_nsegments)(0, "AFTER DECREASE rc -> 0"); + } + } +} + +static void +put_sentinel(UInt ix) +{ + aspacem_assert(ix >= overhead && ix <= segnames_used); + + put_refcount(ix, 0); + put_slotsize(ix, 0); +} + + +/* Searches the string table to find an index for the given name. + If none is found, an index is allocated and the name stored. + If running ouf of memory, return -1. */ +Int +VG_(am_allocate_segname)(const HChar *name) +{ + UInt len, ix, size, next_freeslot; + + aspacem_assert(name); + + if (0) VG_(debugLog)(0, "aspacem", "allocate_segname %s\n", name); + + len = VG_(strlen)(name); + + /* First see if we already have the name. */ + for (ix = overhead; (size = get_slotsize(ix)) != 0; ix += size + overhead) { + if (is_freeslot(ix)) continue; + if (VG_(strcmp)(name, segnames + ix) == 0) { + inc_refcount(ix); + return ix; + } + } + + /* Is there a free slot in the string table from a previously "freed" + segment name ? */ + Int prev; + for (prev = -1, ix = freeslot_chain; ix != end_of_chain; + prev = ix, ix = next_freeslot) { + next_freeslot = get_slotindex(ix); // next in chain + size = get_slotsize(ix); + + if (size >= len + 1) { + /* Note, if the size of the slot is a lot larger than the length + of the string we're about to store in it, we could split the + slot into two. But that complicates matters and as we're not + doing any coalescing of adjacent free slots this could lead to + fragmentation. */ + if (prev == -1) + freeslot_chain = next_freeslot; + else + put_slotindex(prev, next_freeslot); + put_refcount(ix, 1); + put_slotsize(ix, size); + VG_(strcpy)(segnames + ix, name); + ++num_segnames; + return ix; + } + } + + /* We need to add a new name. */ + + /* Note, that we need at least two bytes in the payload. The reason is + that the payload area will be used to store the size of the slot when + the slot is on the freelist. */ + if (len == 0) len = 1; + + /* Is there enough room in the string table? The OVERHEAD is for the + sentinel following the payload of new slot. */ + SizeT need = len + 1 + overhead; + if (need > (sizeof segnames) - segnames_used) { + return -1; + } + + ++num_segnames; + ++num_slots; + + /* copy it in */ + ix = segnames_used; + put_refcount(ix, 1); + put_slotsize(ix, len + 1); + VG_(strcpy)(segnames + ix, name); + segnames_used += need; + + /* Add sentinel at end of segment name list */ + put_sentinel(segnames_used); + + return ix; +} + +/* Debugging output */ +void +VG_(am_show_segnames)(Int logLevel, const HChar *prefix) +{ + UInt size, ix, i; + + VG_(debugLog)(logLevel, "aspacem", "%u segment names in %u slots\n", + num_segnames, num_slots); + + if (freeslot_chain == end_of_chain) + VG_(debugLog)(logLevel, "aspacem", "freelist is empty\n"); + else + VG_(debugLog)(logLevel, "aspacem", "freelist begins at %u\n", + freeslot_chain); + for (i = 0, ix = overhead; (size = get_slotsize(ix)) != 0; + ix += size + overhead, ++i) { + if (is_freeslot(ix)) + VG_(debugLog)(logLevel, "aspacem", + "(%u,%u,0) [free slot: size=%u next=%u]\n", i, ix, + get_slotsize(ix), get_slotindex(ix)); + else + VG_(debugLog)(logLevel, "aspacem", + "(%u,%u,%u) %s\n", i, ix, get_refcount(ix), + segnames + ix); + } +} + +/* Returns a sequence number for the fnIdx position in segnames. + Used in aspacemgr debug output to associate a segment with + a segment name. */ +Int +VG_(am_segname_get_seqnr)(Int fnIdx) +{ + SizeT ix, size; + Int seqnr = -1; + + if (fnIdx == -1) return -1; // shortcut + + for (ix = overhead; (size = get_slotsize(ix)) != 0; ix += size + overhead) { + seqnr++; + if (ix == fnIdx) + return seqnr; + } + + // We should always find the given index; something's busted + aspacem_assert(0); + return -1; +} + +/* Initialise the string table for segment names. It contains an empty + string which is not referenced. */ +void +VG_(am_segnames_init)(void) +{ + aspacem_assert(sizeof segnames >= overhead); + + segnames_used = overhead; + put_sentinel(segnames_used); +} + +/* Increase reference count of segment name identified by IX. */ +void +VG_(am_inc_refcount)(Int ix) +{ + if (ix != -1) + inc_refcount(ix); +} + +/* Decrease reference count of segment name identified by IX. */ +void +VG_(am_dec_refcount)(Int ix) +{ + if (ix != -1) + dec_refcount(ix); +} + +Bool +VG_(am_sane_segname)(Int ix) +{ + return ix == -1 || (ix >= overhead && ix < segnames_used); +} + +const HChar * +VG_(am_get_segname)(Int ix) +{ + return (ix == -1) ? NULL : segnames + ix; +} + +/*--------------------------------------------------------------------*/ +/*--- end ---*/ +/*--------------------------------------------------------------------*/ diff --git a/coregrind/m_aspacemgr/priv_aspacemgr.h b/coregrind/m_aspacemgr/priv_aspacemgr.h index f206e12851..c36dc3af30 100644 --- a/coregrind/m_aspacemgr/priv_aspacemgr.h +++ b/coregrind/m_aspacemgr/priv_aspacemgr.h @@ -131,6 +131,29 @@ Bool ML_(am_resolve_filename) ( Int fd, /*OUT*/HChar* buf, Int nbuf ); extern void ML_(am_do_sanity_check)( void ); +/* ------ Implemented in aspacemgr-segnames.c ------ */ +void VG_(am_segnames_init)(void); +void VG_(am_show_segnames)(Int logLevel, const HChar *prefix); + +/* Put NAME into the string table of segment names. Return index for + future reference. A return value of -1 indicates that the segment name + could not be stored. Basically an out-of-memory situation. */ +Int VG_(am_allocate_segname)(const HChar *name); + +/* Increment / decrement the reference counter for this segment name. */ +void VG_(am_inc_refcount)(Int); +void VG_(am_dec_refcount)(Int); + +/* Check whether the segname index is sane. */ +Bool VG_(am_sane_segname)(Int fnIdx); + +/* Return the segment name for the given index. Maybe return NULL, if the + segment does not have a name. */ +const HChar *VG_(am_get_segname)(Int fnIdx); + +/* Return the sequence number of the segment name */ +Int VG_(am_segname_get_seqnr)(Int fnIdx); + #endif // __PRIV_ASPACEMGR_H /*--------------------------------------------------------------------*/ -- 2.47.3