From fee9e40a8da75fad9717668f6dddcc26f3feca2d Mon Sep 17 00:00:00 2001 From: Adhemerval Zanella Date: Wed, 1 Nov 2023 09:56:08 -0300 Subject: malloc: Decorate malloc maps Add anonymous mmap annotations on loader malloc, malloc when it allocates memory with mmap, and on malloc arena. The /proc/self/maps will now print: [anon: glibc: malloc arena] [anon: glibc: malloc] [anon: glibc: loader malloc] On arena allocation, glibc annotates only the read/write mapping. Checked on x86_64-linux-gnu and aarch64-linux-gnu. Reviewed-by: DJ Delorie --- malloc/arena.c | 4 ++++ malloc/malloc.c | 5 +++++ 2 files changed, 9 insertions(+) (limited to 'malloc') diff --git a/malloc/arena.c b/malloc/arena.c index 6f03955..d1e214a 100644 --- a/malloc/arena.c +++ b/malloc/arena.c @@ -17,6 +17,7 @@ not, see . */ #include +#include #define TUNABLE_NAMESPACE malloc #include @@ -436,6 +437,9 @@ alloc_new_heap (size_t size, size_t top_pad, size_t pagesize, return 0; } + /* Only considere the actual usable range. */ + __set_vma_name (p2, size, " glibc: malloc arena"); + madvise_thp (p2, size); h = (heap_info *) p2; diff --git a/malloc/malloc.c b/malloc/malloc.c index d0bbbf3..78a531b 100644 --- a/malloc/malloc.c +++ b/malloc/malloc.c @@ -218,6 +218,7 @@ #include #include +#include #include #include /* needed for malloc_stats */ @@ -2428,6 +2429,8 @@ sysmalloc_mmap (INTERNAL_SIZE_T nb, size_t pagesize, int extra_flags, mstate av) madvise_thp (mm, size); #endif + __set_vma_name (mm, size, " glibc: malloc"); + /* The offset to the start of the mmapped region is stored in the prev_size field of the chunk. This allows us to adjust returned start address to @@ -2513,6 +2516,8 @@ sysmalloc_mmap_fallback (long int *s, INTERNAL_SIZE_T nb, madvise_thp (mbrk, size); #endif + __set_vma_name (mbrk, size, " glibc: malloc"); + /* Record that we no longer have a contiguous sbrk region. After the first time mmap is used as backup, we do not ever rely on contiguous space since this could incorrectly bridge regions. */ -- cgit v1.1