Add mallinfo2 function that support sizes >= 4GB.

The current int type can easily overflow for allocation of more
than 4GB.
This commit is contained in:
Martin Liska 2020-07-07 13:58:24 +02:00
parent 85f1848937
commit e3960d1c57
3 changed files with 69 additions and 23 deletions

View File

@ -638,6 +638,8 @@ libc_hidden_proto (__libc_mallopt)
be kept as longs, the reported values may wrap around zero and
thus be inaccurate.
*/
struct mallinfo2 __libc_mallinfo2(void);
struct mallinfo __libc_mallinfo(void);
@ -4911,7 +4913,7 @@ __malloc_usable_size (void *m)
*/
static void
int_mallinfo (mstate av, struct mallinfo *m)
int_mallinfo (mstate av, struct mallinfo2 *m)
{
size_t i;
mbinptr b;
@ -4974,10 +4976,10 @@ int_mallinfo (mstate av, struct mallinfo *m)
}
struct mallinfo
__libc_mallinfo (void)
struct mallinfo2
__libc_mallinfo2 (void)
{
struct mallinfo m;
struct mallinfo2 m;
mstate ar_ptr;
if (__malloc_initialized < 0)
@ -4998,6 +5000,27 @@ __libc_mallinfo (void)
return m;
}
struct mallinfo
__libc_mallinfo (void)
{
struct mallinfo m;
struct mallinfo2 m2 = __libc_mallinfo2 ();
m.arena = m2.arena;
m.ordblks = m2.ordblks;
m.smblks = m2.smblks;
m.hblks = m2.hblks;
m.hblkhd = m2.hblkhd;
m.usmblks = m2.usmblks;
m.fsmblks = m2.fsmblks;
m.uordblks = m2.uordblks;
m.fordblks = m2.fordblks;
m.keepcost = m2.keepcost;
return m;
}
/*
------------------------------ malloc_stats ------------------------------
*/
@ -5016,7 +5039,7 @@ __malloc_stats (void)
stderr->_flags2 |= _IO_FLAGS2_NOTCANCEL;
for (i = 0, ar_ptr = &main_arena;; i++)
{
struct mallinfo mi;
struct mallinfo2 mi;
memset (&mi, 0, sizeof (mi));
__libc_lock_lock (ar_ptr->mutex);
@ -5632,6 +5655,8 @@ strong_alias (__libc_valloc, __valloc) weak_alias (__libc_valloc, valloc)
strong_alias (__libc_pvalloc, __pvalloc) weak_alias (__libc_pvalloc, pvalloc)
strong_alias (__libc_mallinfo, __mallinfo)
weak_alias (__libc_mallinfo, mallinfo)
strong_alias (__libc_mallinfo2, __mallinfo2)
weak_alias (__libc_mallinfo2, mallinfo2)
strong_alias (__libc_mallopt, __mallopt) weak_alias (__libc_mallopt, mallopt)
weak_alias (__malloc_stats, malloc_stats)

View File

@ -97,9 +97,30 @@ struct mallinfo
int keepcost; /* top-most, releasable (via malloc_trim) space */
};
/* SVID2/XPG mallinfo2 structure which can handle allocations
bigger than 4GB. */
struct mallinfo2
{
size_t arena; /* non-mmapped space allocated from system */
size_t ordblks; /* number of free chunks */
size_t smblks; /* number of fastbin blocks */
size_t hblks; /* number of mmapped regions */
size_t hblkhd; /* space in mmapped regions */
size_t usmblks; /* always 0, preserved for backwards compatibility */
size_t fsmblks; /* space available in freed fastbin blocks */
size_t uordblks; /* total allocated space */
size_t fordblks; /* total free space */
size_t keepcost; /* top-most, releasable (via malloc_trim) space */
};
/* Returns a copy of the updated current mallinfo. */
__MALLOC_DEPRECATED;
extern struct mallinfo mallinfo (void) __THROW;
/* Returns a copy of the updated current mallinfo. */
extern struct mallinfo2 mallinfo2 (void) __THROW;
/* SVID2/XPG mallopt options */
#ifndef M_MXFAST
# define M_MXFAST 1 /* maximum request size for "fastbins" */

View File

@ -1505,50 +1505,50 @@ installing such hooks.
@cindex allocation statistics
You can get information about dynamic memory allocation by calling the
@code{mallinfo} function. This function and its associated data type
@code{mallinfo2} function. This function and its associated data type
are declared in @file{malloc.h}; they are an extension of the standard
SVID/XPG version.
@pindex malloc.h
@deftp {Data Type} {struct mallinfo}
@deftp {Data Type} {struct mallinfo2}
@standards{GNU, malloc.h}
This structure type is used to return information about the dynamic
memory allocator. It contains the following members:
@table @code
@item int arena
@item size_t arena
This is the total size of memory allocated with @code{sbrk} by
@code{malloc}, in bytes.
@item int ordblks
@item size_t ordblks
This is the number of chunks not in use. (The memory allocator
internally gets chunks of memory from the operating system, and then
size_ternally gets chunks of memory from the operating system, and then
carves them up to satisfy individual @code{malloc} requests;
@pxref{The GNU Allocator}.)
@item int smblks
@item size_t smblks
This field is unused.
@item int hblks
@item size_t hblks
This is the total number of chunks allocated with @code{mmap}.
@item int hblkhd
@item size_t hblkhd
This is the total size of memory allocated with @code{mmap}, in bytes.
@item int usmblks
@item size_t usmblks
This field is unused and always 0.
@item int fsmblks
@item size_t fsmblks
This field is unused.
@item int uordblks
@item size_t uordblks
This is the total size of memory occupied by chunks handed out by
@code{malloc}.
@item int fordblks
@item size_t fordblks
This is the total size of memory occupied by free (not in use) chunks.
@item int keepcost
@item size_t keepcost
This is the size of the top-most releasable chunk that normally
borders the end of the heap (i.e., the high end of the virtual address
space's data segment).
@ -1556,7 +1556,7 @@ space's data segment).
@end table
@end deftp
@deftypefun {struct mallinfo} mallinfo (void)
@deftypefun {struct mallinfo2} mallinfo2 (void)
@standards{SVID, malloc.h}
@safety{@prelim{}@mtunsafe{@mtuinit{} @mtasuconst{:mallopt}}@asunsafe{@asuinit{} @asulock{}}@acunsafe{@acuinit{} @aculock{}}}
@c Accessing mp_.n_mmaps and mp_.max_mmapped_mem, modified with atomics
@ -1564,7 +1564,7 @@ space's data segment).
@c mark the statistics as unsafe, rather than the fast-path functions
@c that collect the possibly inconsistent data.
@c __libc_mallinfo @mtuinit @mtasuconst:mallopt @asuinit @asulock @aculock
@c __libc_mallinfo2 @mtuinit @mtasuconst:mallopt @asuinit @asulock @aculock
@c ptmalloc_init (once) dup @mtsenv @asulock @aculock @acsfd @acsmem
@c mutex_lock dup @asulock @aculock
@c int_mallinfo @mtasuconst:mallopt [mp_ access on main_arena]
@ -1577,7 +1577,7 @@ space's data segment).
@c mutex_unlock @aculock
This function returns information about the current dynamic memory usage
in a structure of type @code{struct mallinfo}.
in a structure of type @code{struct mallinfo2}.
@end deftypefun
@node Summary of Malloc
@ -1644,7 +1644,7 @@ A pointer to a function that @code{free} uses whenever it is called.
A pointer to a function that @code{aligned_alloc}, @code{memalign},
@code{posix_memalign} and @code{valloc} use whenever they are called.
@item struct mallinfo mallinfo (void)
@item struct mallinfo2 mallinfo2 (void)
Return information about the current dynamic memory usage.
@xref{Statistics of Malloc}.
@end table
@ -1970,7 +1970,7 @@ In addition, very old applications may use the obsolete @code{cfree}
function.
Further @code{malloc}-related functions such as @code{mallopt} or
@code{mallinfo} will not have any effect or return incorrect statistics
@code{mallinfo2} will not have any effect or return incorrect statistics
when a replacement @code{malloc} is in use. However, failure to replace
these functions typically does not result in crashes or other incorrect
application behavior, but may result in static linking failures.