From f033b688c1ede5ec78c9a718fa9f0b374049bc31 Mon Sep 17 00:00:00 2001 From: Jesper Dangaard Brouer Date: Tue, 18 Jun 2019 15:05:58 +0200 Subject: [PATCH] xdp: add tracepoints for XDP mem These tracepoints make it easier to troubleshoot XDP mem id disconnect. The xdp:mem_disconnect tracepoint cannot be replaced via kprobe. It is placed at the last stable place for the pointer to struct xdp_mem_allocator, just before it's scheduled for RCU removal. It also extract info on 'safe_to_remove' and 'force'. Detailed info about in-flight pages is not available at this layer. The next patch will added tracepoints needed at the page_pool layer for this. Signed-off-by: Jesper Dangaard Brouer Signed-off-by: David S. Miller --- include/net/xdp_priv.h | 23 +++++++++ include/trace/events/xdp.h | 115 +++++++++++++++++++++++++++++++++++++++++++++ net/core/xdp.c | 21 ++------- 3 files changed, 143 insertions(+), 16 deletions(-) create mode 100644 include/net/xdp_priv.h diff --git a/include/net/xdp_priv.h b/include/net/xdp_priv.h new file mode 100644 index 000000000000..6a8cba6ea79a --- /dev/null +++ b/include/net/xdp_priv.h @@ -0,0 +1,23 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef __LINUX_NET_XDP_PRIV_H__ +#define __LINUX_NET_XDP_PRIV_H__ + +#include + +/* Private to net/core/xdp.c, but used by trace/events/xdp.h */ +struct xdp_mem_allocator { + struct xdp_mem_info mem; + union { + void *allocator; + struct page_pool *page_pool; + struct zero_copy_allocator *zc_alloc; + }; + int disconnect_cnt; + unsigned long defer_start; + struct rhash_head node; + struct rcu_head rcu; + struct delayed_work defer_wq; + unsigned long defer_warn; +}; + +#endif /* __LINUX_NET_XDP_PRIV_H__ */ diff --git a/include/trace/events/xdp.h b/include/trace/events/xdp.h index e95cb86b65cf..bb5e380e2ef3 100644 --- a/include/trace/events/xdp.h +++ b/include/trace/events/xdp.h @@ -269,6 +269,121 @@ TRACE_EVENT(xdp_devmap_xmit, __entry->from_ifindex, __entry->to_ifindex, __entry->err) ); +/* Expect users already include , but not xdp_priv.h */ +#include + +#define __MEM_TYPE_MAP(FN) \ + FN(PAGE_SHARED) \ + FN(PAGE_ORDER0) \ + FN(PAGE_POOL) \ + FN(ZERO_COPY) + +#define __MEM_TYPE_TP_FN(x) \ + TRACE_DEFINE_ENUM(MEM_TYPE_##x); +#define __MEM_TYPE_SYM_FN(x) \ + { MEM_TYPE_##x, #x }, +#define __MEM_TYPE_SYM_TAB \ + __MEM_TYPE_MAP(__MEM_TYPE_SYM_FN) { -1, 0 } +__MEM_TYPE_MAP(__MEM_TYPE_TP_FN) + +TRACE_EVENT(mem_disconnect, + + TP_PROTO(const struct xdp_mem_allocator *xa, + bool safe_to_remove, bool force), + + TP_ARGS(xa, safe_to_remove, force), + + TP_STRUCT__entry( + __field(const struct xdp_mem_allocator *, xa) + __field(u32, mem_id) + __field(u32, mem_type) + __field(const void *, allocator) + __field(bool, safe_to_remove) + __field(bool, force) + __field(int, disconnect_cnt) + ), + + TP_fast_assign( + __entry->xa = xa; + __entry->mem_id = xa->mem.id; + __entry->mem_type = xa->mem.type; + __entry->allocator = xa->allocator; + __entry->safe_to_remove = safe_to_remove; + __entry->force = force; + __entry->disconnect_cnt = xa->disconnect_cnt; + ), + + TP_printk("mem_id=%d mem_type=%s allocator=%p" + " safe_to_remove=%s force=%s disconnect_cnt=%d", + __entry->mem_id, + __print_symbolic(__entry->mem_type, __MEM_TYPE_SYM_TAB), + __entry->allocator, + __entry->safe_to_remove ? "true" : "false", + __entry->force ? "true" : "false", + __entry->disconnect_cnt + ) +); + +TRACE_EVENT(mem_connect, + + TP_PROTO(const struct xdp_mem_allocator *xa, + const struct xdp_rxq_info *rxq), + + TP_ARGS(xa, rxq), + + TP_STRUCT__entry( + __field(const struct xdp_mem_allocator *, xa) + __field(u32, mem_id) + __field(u32, mem_type) + __field(const void *, allocator) + __field(const struct xdp_rxq_info *, rxq) + __field(int, ifindex) + ), + + TP_fast_assign( + __entry->xa = xa; + __entry->mem_id = xa->mem.id; + __entry->mem_type = xa->mem.type; + __entry->allocator = xa->allocator; + __entry->rxq = rxq; + __entry->ifindex = rxq->dev->ifindex; + ), + + TP_printk("mem_id=%d mem_type=%s allocator=%p" + " ifindex=%d", + __entry->mem_id, + __print_symbolic(__entry->mem_type, __MEM_TYPE_SYM_TAB), + __entry->allocator, + __entry->ifindex + ) +); + +TRACE_EVENT(mem_return_failed, + + TP_PROTO(const struct xdp_mem_info *mem, + const struct page *page), + + TP_ARGS(mem, page), + + TP_STRUCT__entry( + __field(const struct page *, page) + __field(u32, mem_id) + __field(u32, mem_type) + ), + + TP_fast_assign( + __entry->page = page; + __entry->mem_id = mem->id; + __entry->mem_type = mem->type; + ), + + TP_printk("mem_id=%d mem_type=%s page=%p", + __entry->mem_id, + __print_symbolic(__entry->mem_type, __MEM_TYPE_SYM_TAB), + __entry->page + ) +); + #endif /* _TRACE_XDP_H */ #include diff --git a/net/core/xdp.c b/net/core/xdp.c index 622c81dc7ba8..b29d7b513a18 100644 --- a/net/core/xdp.c +++ b/net/core/xdp.c @@ -14,6 +14,8 @@ #include #include +#include /* struct xdp_mem_allocator */ +#include #define REG_STATE_NEW 0x0 #define REG_STATE_REGISTERED 0x1 @@ -29,21 +31,6 @@ static int mem_id_next = MEM_ID_MIN; static bool mem_id_init; /* false */ static struct rhashtable *mem_id_ht; -struct xdp_mem_allocator { - struct xdp_mem_info mem; - union { - void *allocator; - struct page_pool *page_pool; - struct zero_copy_allocator *zc_alloc; - }; - struct rhash_head node; - struct rcu_head rcu; - struct delayed_work defer_wq; - unsigned long defer_start; - unsigned long defer_warn; - int disconnect_cnt; -}; - static u32 xdp_mem_id_hashfn(const void *data, u32 len, u32 seed) { const u32 *k = data; @@ -117,7 +104,7 @@ bool __mem_id_disconnect(int id, bool force) if (xa->mem.type == MEM_TYPE_PAGE_POOL) safe_to_remove = page_pool_request_shutdown(xa->page_pool); - /* TODO: Tracepoint will be added here in next-patch */ + trace_mem_disconnect(xa, safe_to_remove, force); if ((safe_to_remove || force) && !rhashtable_remove_fast(mem_id_ht, &xa->node, mem_id_rht_params)) @@ -385,6 +372,7 @@ int xdp_rxq_info_reg_mem_model(struct xdp_rxq_info *xdp_rxq, mutex_unlock(&mem_id_lock); + trace_mem_connect(xdp_alloc, xdp_rxq); return 0; err: mutex_unlock(&mem_id_lock); @@ -417,6 +405,7 @@ static void __xdp_return(void *data, struct xdp_mem_info *mem, bool napi_direct, } else { /* Hopefully stack show who to blame for late return */ WARN_ONCE(1, "page_pool gone mem.id=%d", mem->id); + trace_mem_return_failed(mem, page); put_page(page); } rcu_read_unlock(); -- 2.11.0