From 7aee8429eedd0970d8add2fb5b856bfc5f5f1fc1 Mon Sep 17 00:00:00 2001 From: Jakub Kicinski Date: Sun, 26 Nov 2023 15:07:36 -0800 Subject: [PATCH] net: page_pool: report amount of memory held by page pools Advanced deployments need the ability to check memory use of various system components. It makes it possible to make informed decisions about memory allocation and to find regressions and leaks. Report memory use of page pools. Report both number of references and bytes held. Acked-by: Jesper Dangaard Brouer Signed-off-by: Jakub Kicinski Signed-off-by: Paolo Abeni --- Documentation/netlink/specs/netdev.yaml | 15 +++++++++++++++ include/uapi/linux/netdev.h | 2 ++ net/core/page_pool.c | 13 +++++++++---- net/core/page_pool_priv.h | 2 ++ net/core/page_pool_user.c | 8 ++++++++ 5 files changed, 36 insertions(+), 4 deletions(-) diff --git a/Documentation/netlink/specs/netdev.yaml b/Documentation/netlink/specs/netdev.yaml index 82fbe81f7a49..b76623ff2932 100644 --- a/Documentation/netlink/specs/netdev.yaml +++ b/Documentation/netlink/specs/netdev.yaml @@ -114,6 +114,19 @@ attribute-sets: checks: min: 1 max: u32-max + - + name: inflight + type: uint + doc: | + Number of outstanding references to this page pool (allocated + but yet to be freed pages). Allocated pages may be held in + socket receive queues, driver receive ring, page pool recycling + ring, the page pool cache, etc. + - + name: inflight-mem + type: uint + doc: | + Amount of memory held by inflight pages. operations: list: @@ -163,6 +176,8 @@ operations: - id - ifindex - napi-id + - inflight + - inflight-mem dump: reply: *pp-reply config-cond: page-pool diff --git a/include/uapi/linux/netdev.h b/include/uapi/linux/netdev.h index beb158872226..26ae5bdd3187 100644 --- a/include/uapi/linux/netdev.h +++ b/include/uapi/linux/netdev.h @@ -68,6 +68,8 @@ enum { NETDEV_A_PAGE_POOL_ID = 1, NETDEV_A_PAGE_POOL_IFINDEX, NETDEV_A_PAGE_POOL_NAPI_ID, + NETDEV_A_PAGE_POOL_INFLIGHT, + NETDEV_A_PAGE_POOL_INFLIGHT_MEM, __NETDEV_A_PAGE_POOL_MAX, NETDEV_A_PAGE_POOL_MAX = (__NETDEV_A_PAGE_POOL_MAX - 1) diff --git a/net/core/page_pool.c b/net/core/page_pool.c index a8d96ea38d18..566390759294 100644 --- a/net/core/page_pool.c +++ b/net/core/page_pool.c @@ -529,7 +529,7 @@ EXPORT_SYMBOL(page_pool_alloc_pages); */ #define _distance(a, b) (s32)((a) - (b)) -static s32 page_pool_inflight(struct page_pool *pool) +s32 page_pool_inflight(const struct page_pool *pool, bool strict) { u32 release_cnt = atomic_read(&pool->pages_state_release_cnt); u32 hold_cnt = READ_ONCE(pool->pages_state_hold_cnt); @@ -537,8 +537,13 @@ static s32 page_pool_inflight(struct page_pool *pool) inflight = _distance(hold_cnt, release_cnt); - trace_page_pool_release(pool, inflight, hold_cnt, release_cnt); - WARN(inflight < 0, "Negative(%d) inflight packet-pages", inflight); + if (strict) { + trace_page_pool_release(pool, inflight, hold_cnt, release_cnt); + WARN(inflight < 0, "Negative(%d) inflight packet-pages", + inflight); + } else { + inflight = max(0, inflight); + } return inflight; } @@ -881,7 +886,7 @@ static int page_pool_release(struct page_pool *pool) int inflight; page_pool_scrub(pool); - inflight = page_pool_inflight(pool); + inflight = page_pool_inflight(pool, true); if (!inflight) __page_pool_destroy(pool); diff --git a/net/core/page_pool_priv.h b/net/core/page_pool_priv.h index c17ea092b4ab..72fb21ea1ddc 100644 --- a/net/core/page_pool_priv.h +++ b/net/core/page_pool_priv.h @@ -3,6 +3,8 @@ #ifndef __PAGE_POOL_PRIV_H #define __PAGE_POOL_PRIV_H +s32 page_pool_inflight(const struct page_pool *pool, bool strict); + int page_pool_list(struct page_pool *pool); void page_pool_unlist(struct page_pool *pool); diff --git a/net/core/page_pool_user.c b/net/core/page_pool_user.c index 1577fef880c9..2db71e718485 100644 --- a/net/core/page_pool_user.c +++ b/net/core/page_pool_user.c @@ -110,6 +110,7 @@ static int page_pool_nl_fill(struct sk_buff *rsp, const struct page_pool *pool, const struct genl_info *info) { + size_t inflight, refsz; void *hdr; hdr = genlmsg_iput(rsp, info); @@ -127,6 +128,13 @@ page_pool_nl_fill(struct sk_buff *rsp, const struct page_pool *pool, nla_put_uint(rsp, NETDEV_A_PAGE_POOL_NAPI_ID, pool->user.napi_id)) goto err_cancel; + inflight = page_pool_inflight(pool, false); + refsz = PAGE_SIZE << pool->p.order; + if (nla_put_uint(rsp, NETDEV_A_PAGE_POOL_INFLIGHT, inflight) || + nla_put_uint(rsp, NETDEV_A_PAGE_POOL_INFLIGHT_MEM, + inflight * refsz)) + goto err_cancel; + genlmsg_end(rsp, hdr); return 0;