eal: change alloc_sz calculation which may cause unnecessarily allocation
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Commit Message
In try_expand_heap() alloc_sz is calculated which may result in
unnecessary allocation of whole huge page, this may cause allocation
limit from system or eal
In response to this mail:
<CAEYuUWCnRZNwxiOHEeTHw0Gy9aFJRLZtvAG9g=smuUvUEMcFXg@mail.gmail.com>
Signed-off-by: Fidaullah Noonari <fidaullah.noonari@emumba.com>
---
lib/eal/common/malloc_heap.c | 2 +-
lib/eal/common/malloc_mp.c | 2 +-
2 files changed, 2 insertions(+), 2 deletions(-)
Comments
2022-07-18 09:11 (UTC+0500), Fidaullah Noonari:
> In try_expand_heap() alloc_sz is calculated
> which may result in unnecessary allocation of whole huge page,
> this may cause allocation limit from system or eal
Let me suggest a rewording:
The amount of memory to allocate from the system for heap expansion
was calculated in a way that may yield one page more than needed.
This could hit the allocation limit from the system or EAL.
The allocation would fail despite enough memory being available.
> In response to this mail:
> <CAEYuUWCnRZNwxiOHEeTHw0Gy9aFJRLZtvAG9g=smuUvUEMcFXg@mail.gmail.com>
Proper links to mails.dpdk.org or inbox.dpdk.org are preferred.
>
> Signed-off-by: Fidaullah Noonari <fidaullah.noonari@emumba.com>
> ---
> lib/eal/common/malloc_heap.c | 2 +-
> lib/eal/common/malloc_mp.c | 2 +-
> 2 files changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/lib/eal/common/malloc_heap.c b/lib/eal/common/malloc_heap.c
> index 27a52266ad..e348e385e4 100644
> --- a/lib/eal/common/malloc_heap.c
> +++ b/lib/eal/common/malloc_heap.c
> @@ -402,7 +402,7 @@ try_expand_heap_primary(struct malloc_heap *heap, uint64_t pg_sz,
> int n_segs;
> bool callback_triggered = false;
>
> - alloc_sz = RTE_ALIGN_CEIL(align + elt_size +
> + alloc_sz = RTE_ALIGN_CEIL(RTE_ALIGN_CEIL(align, elt_size) +
> MALLOC_ELEM_OVERHEAD, pg_sz);
> n_segs = alloc_sz / pg_sz;
>
> diff --git a/lib/eal/common/malloc_mp.c b/lib/eal/common/malloc_mp.c
> index 2b8eb51067..1b79ed5e21 100644
> --- a/lib/eal/common/malloc_mp.c
> +++ b/lib/eal/common/malloc_mp.c
> @@ -249,7 +249,7 @@ handle_alloc_request(const struct malloc_mp_req *m,
> return -1;
> }
>
> - alloc_sz = RTE_ALIGN_CEIL(ar->align + ar->elt_size +
> + alloc_sz = RTE_ALIGN_CEIL(RTE_ALIGN_CEIL(ar->align, ar->elt_size) +
> MALLOC_ELEM_OVERHEAD, ar->page_sz);
> n_segs = alloc_sz / ar->page_sz;
>
Wrong argument order for RTE_ALIGN_CEIL(size, alignment) in both places.
@@ -402,7 +402,7 @@ try_expand_heap_primary(struct malloc_heap *heap, uint64_t pg_sz,
int n_segs;
bool callback_triggered = false;
- alloc_sz = RTE_ALIGN_CEIL(align + elt_size +
+ alloc_sz = RTE_ALIGN_CEIL(RTE_ALIGN_CEIL(align, elt_size) +
MALLOC_ELEM_OVERHEAD, pg_sz);
n_segs = alloc_sz / pg_sz;
@@ -249,7 +249,7 @@ handle_alloc_request(const struct malloc_mp_req *m,
return -1;
}
- alloc_sz = RTE_ALIGN_CEIL(ar->align + ar->elt_size +
+ alloc_sz = RTE_ALIGN_CEIL(RTE_ALIGN_CEIL(ar->align, ar->elt_size) +
MALLOC_ELEM_OVERHEAD, ar->page_sz);
n_segs = alloc_sz / ar->page_sz;