This is the mail archive of the
libc-alpha@sourceware.org
mailing list for the glibc project.
Re: [PATCH] malloc: Account for all heaps in an arena in malloc_info [BZ #22439]
- From: Siddhesh Poyarekar <siddhesh at gotplt dot org>
- To: Florian Weimer <fweimer at redhat dot com>, libc-alpha at sourceware dot org
- Date: Wed, 15 Nov 2017 09:03:42 +0530
- Subject: Re: [PATCH] malloc: Account for all heaps in an arena in malloc_info [BZ #22439]
- Authentication-results: sourceware.org; auth=none
- References: <20171114180833.5FA9E423CD593@oldenburg.str.redhat.com>
On Tuesday 14 November 2017 11:38 PM, Florian Weimer wrote:
> This commit adds a "subheads" statistics to the malloc_info output.
How about something like this for the description:
"This commit adds a "subheaps" field to the malloc_info output that
shows the number of heaps that were allocated to extend a non-main arena."
Looks OK otherwise.
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
> 2017-11-14 Florian Weimer <fweimer@redhat.com>
>
> [BZ #22408]
> * malloc/malloc.c (__malloc_info): Count all heaps in an arena,
> not just the top one. Output a new "subheaps" statistic.
>
> diff --git a/NEWS b/NEWS
> index b7281621f4..520db40982 100644
> --- a/NEWS
> +++ b/NEWS
> @@ -63,6 +63,9 @@ Deprecated and removed features, and other changes affecting compatibility:
> * The res_hnok, res_dnok, res_mailok and res_ownok functions now check that
> the specified string can be parsed as a domain name.
>
> +* In the malloc_info output, the <heap> element may contain another <aspace>
> + element, "subheaps", which contains the number of sub-heaps.
> +
> Changes to build and runtime requirements:
>
> [Add changes to build and runtime requirements here]
> diff --git a/malloc/malloc.c b/malloc/malloc.c
> index 0494e8c39f..2999ac4d2f 100644
> --- a/malloc/malloc.c
> +++ b/malloc/malloc.c
> @@ -5457,11 +5457,19 @@ __malloc_info (int options, FILE *fp)
>
> size_t heap_size = 0;
> size_t heap_mprotect_size = 0;
> + size_t heap_count = 0;
> if (ar_ptr != &main_arena)
> {
> + /* Iterate over the arena heaps from back to front. */
> heap_info *heap = heap_for_ptr (top (ar_ptr));
> - heap_size = heap->size;
> - heap_mprotect_size = heap->mprotect_size;
> + do
> + {
> + heap_size += heap->size;
> + heap_mprotect_size += heap->mprotect_size;
> + heap = heap->prev;
> + ++heap_count;
> + }
> + while (heap != NULL);
> }
>
> __libc_lock_unlock (ar_ptr->mutex);
> @@ -5499,8 +5507,9 @@ __malloc_info (int options, FILE *fp)
> {
> fprintf (fp,
> "<aspace type=\"total\" size=\"%zu\"/>\n"
> - "<aspace type=\"mprotect\" size=\"%zu\"/>\n",
> - heap_size, heap_mprotect_size);
> + "<aspace type=\"mprotect\" size=\"%zu\"/>\n"
> + "<aspace type=\"subheaps\" size=\"%zu\"/>\n",
> + heap_size, heap_mprotect_size, heap_count);
> total_aspace += heap_size;
> total_aspace_mprotect += heap_mprotect_size;
> }
>