New configure option '--enable-pageid' for Linux

The option makes jemalloc use prctl with PR_SET_VMA to tag memory mappings with
"jemalloc_pg" or "jemalloc_pg_overcommit". This allows to easily identify
jemalloc's mappings in /proc/<pid>/maps. PR_SET_VMA is only available in Linux
5.17 and above.
This commit is contained in:
David Carlier 2022-06-01 22:04:11 +01:00 committed by Alex Lapenkou
parent b950934916
commit 4fc5c4fbac
3 changed files with 59 additions and 0 deletions

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@ -2067,6 +2067,14 @@ if test "x$have_memcntl" = "x1" ; then
AC_DEFINE([JEMALLOC_HAVE_MEMCNTL], [ ], [ ]) AC_DEFINE([JEMALLOC_HAVE_MEMCNTL], [ ], [ ])
fi fi
AC_CHECK_FUNC([prctl],
[have_prctl="1"],
[have_prctl="0"],
)
if test "x$have_prctl" = "x1" ; then
AC_DEFINE([JEMALLOC_HAVE_PRCTL], [ ], [ ])
fi
dnl Disable lazy locking by default. dnl Disable lazy locking by default.
AC_ARG_ENABLE([lazy_lock], AC_ARG_ENABLE([lazy_lock],
[AS_HELP_STRING([--enable-lazy-lock], [AS_HELP_STRING([--enable-lazy-lock],
@ -2435,6 +2443,22 @@ else
AC_DEFINE([JEMALLOC_TLS_MODEL], [ ], [ ]) AC_DEFINE([JEMALLOC_TLS_MODEL], [ ], [ ])
fi fi
dnl Do not compile with debugging by default.
AC_ARG_ENABLE([pageid],
[AS_HELP_STRING([--enable-pageid],
[Enable named pages])],
[if test "x$enable_pageid" = "xno" ; then
enable_pageid="0"
else
enable_pageid="1"
fi
],
[enable_pageid="0"]
)
if test "x$enable_pageid" = "x1" ; then
AC_DEFINE([JEMALLOC_PAGEID], [ ], [ ])
fi
dnl ============================================================================ dnl ============================================================================
dnl Enable background threads if possible. dnl Enable background threads if possible.
@ -2691,5 +2715,6 @@ AC_MSG_RESULT([xmalloc : ${enable_xmalloc}])
AC_MSG_RESULT([log : ${enable_log}]) AC_MSG_RESULT([log : ${enable_log}])
AC_MSG_RESULT([lazy_lock : ${enable_lazy_lock}]) AC_MSG_RESULT([lazy_lock : ${enable_lazy_lock}])
AC_MSG_RESULT([cache-oblivious : ${enable_cache_oblivious}]) AC_MSG_RESULT([cache-oblivious : ${enable_cache_oblivious}])
AC_MSG_RESULT([pageid : ${enable_pageid}])
AC_MSG_RESULT([cxx : ${enable_cxx}]) AC_MSG_RESULT([cxx : ${enable_cxx}])
AC_MSG_RESULT([===============================================================================]) AC_MSG_RESULT([===============================================================================])

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@ -162,6 +162,12 @@
/* Use gcc intrinsics for profile backtracing if defined. */ /* Use gcc intrinsics for profile backtracing if defined. */
#undef JEMALLOC_PROF_GCC #undef JEMALLOC_PROF_GCC
/* JEMALLOC_PAGEID enabled page id */
#undef JEMALLOC_PAGEID
/* JEMALLOC_HAVE_PRCTL checks prctl */
#undef JEMALLOC_HAVE_PRCTL
/* /*
* JEMALLOC_DSS enables use of sbrk(2) to allocate extents from the data storage * JEMALLOC_DSS enables use of sbrk(2) to allocate extents from the data storage
* segment (DSS). * segment (DSS).

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@ -21,6 +21,13 @@
#else #else
#define PAGES_FD_TAG -1 #define PAGES_FD_TAG -1
#endif #endif
#ifdef JEMALLOC_HAVE_PRCTL
#include <sys/prctl.h>
#ifndef PR_SET_VMA
#define PR_SET_VMA 0x53564d41
#define PR_SET_VMA_ANON_NAME 0
#endif
#endif
/******************************************************************************/ /******************************************************************************/
/* Data. */ /* Data. */
@ -98,6 +105,22 @@ static int madvise_MADV_DONTNEED_zeroes_pages()
} }
#endif #endif
#ifdef JEMALLOC_PAGEID
static int os_page_id(void *addr, size_t size, const char *name)
{
#ifdef JEMALLOC_HAVE_PRCTL
/*
* While parsing `/proc/<pid>/maps` file, the block could appear as
* 7f4836000000-7f4836800000 rw-p 00000000 00:00 0 [anon:jemalloc_pg_overcommit]`
*/
return prctl(PR_SET_VMA, PR_SET_VMA_ANON_NAME, (uintptr_t)addr, size,
(uintptr_t)name);
#else
return 0;
#endif
}
#endif
/******************************************************************************/ /******************************************************************************/
/* /*
* Function prototypes for static functions that are referenced prior to * Function prototypes for static functions that are referenced prior to
@ -162,6 +185,11 @@ os_pages_map(void *addr, size_t size, size_t alignment, bool *commit) {
#endif #endif
assert(ret == NULL || (addr == NULL && ret != addr) || (addr != NULL && assert(ret == NULL || (addr == NULL && ret != addr) || (addr != NULL &&
ret == addr)); ret == addr));
#ifdef JEMALLOC_PAGEID
int n = os_page_id(ret, size,
os_overcommits ? "jemalloc_pg_overcommit" : "jemalloc_pg");
assert(n == 0 || (n == -1 && get_errno() == EINVAL));
#endif
return ret; return ret;
} }