From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id C1A2F45CE2; Tue, 12 Nov 2024 03:02:48 +0100 (CET) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id B4227427E8; Tue, 12 Nov 2024 03:02:27 +0100 (CET) Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by mails.dpdk.org (Postfix) with ESMTP id 77D44427CE for ; Tue, 12 Nov 2024 03:02:20 +0100 (CET) Received: by linux.microsoft.com (Postfix, from userid 1213) id 8836F23834AD; Mon, 11 Nov 2024 18:02:19 -0800 (PST) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 8836F23834AD DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1731376939; bh=1jz0Vigl2DJGnz5vOfD/akbu44q/PzHm0gMs+1Hc3lE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rPjO1apAqgiq3GTn/KfiXADKGiEBcGGNbp/Og0tMCq3ssZK0/sq26wp40PD1iA1ot EVe4+g7nGLKXysAJ81rEUD1Ry/7f9sf8aNp+NCTJwagE1QjUG9Isn5H8BFdgQV5A7F UvZ60x3o849v3lg6B1prxJJQnZj0QeA7HCAyPVog= From: Andre Muezerie To: dev@dpdk.org Cc: Konstantin Ananyev Subject: [PATCH v7 02/21] eal/linux: remove use of VLAs Date: Mon, 11 Nov 2024 18:01:54 -0800 Message-Id: <1731376933-19275-3-git-send-email-andremue@linux.microsoft.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1731376933-19275-1-git-send-email-andremue@linux.microsoft.com> References: <1713397319-26135-1-git-send-email-roretzla@linux.microsoft.com> <1731376933-19275-1-git-send-email-andremue@linux.microsoft.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org From: Konstantin Ananyev 1) ./lib/eal/linux/eal_interrupts.c:1073:16 : warning: ISO C90 forbids variable length array ‘events’ MSVC does not support VLAs. Use alloca() to allocate the memory on the stack. 2) ./lib/eal/linux/eal_interrupts.c:1319:16 : warning: ISO C90 forbids variable length array ‘evs’ make eal_epoll_wait() use a fixed size array and use it though multiple iterations to process up to @maxevents events. Note that technically it is not one to one replacement, as here we might reduce number of events returned by first call to epoll_wait(..., timeout); Signed-off-by: Konstantin Ananyev --- lib/eal/linux/eal_interrupts.c | 32 +++++++++++++++++++++++++++----- 1 file changed, 27 insertions(+), 5 deletions(-) diff --git a/lib/eal/linux/eal_interrupts.c b/lib/eal/linux/eal_interrupts.c index 6436f796eb..23039964fc 100644 --- a/lib/eal/linux/eal_interrupts.c +++ b/lib/eal/linux/eal_interrupts.c @@ -34,6 +34,8 @@ #define EAL_INTR_EPOLL_WAIT_FOREVER (-1) #define NB_OTHER_INTR 1 +#define MAX_ITER_EVNUM RTE_EVENT_ETH_INTR_RING_SIZE + static RTE_DEFINE_PER_LCORE(int, _epfd) = -1; /**< epoll fd per thread */ /** @@ -1070,7 +1072,7 @@ eal_intr_process_interrupts(struct epoll_event *events, int nfds) static void eal_intr_handle_interrupts(int pfd, unsigned totalfds) { - struct epoll_event events[totalfds]; + struct epoll_event *events = alloca(sizeof(struct epoll_event) * totalfds); int nfds = 0; for(;;) { @@ -1316,8 +1318,9 @@ static int eal_epoll_wait(int epfd, struct rte_epoll_event *events, int maxevents, int timeout, bool interruptible) { - struct epoll_event evs[maxevents]; int rc; + uint32_t i, k, n, num; + struct epoll_event evs[MAX_ITER_EVNUM]; if (!events) { EAL_LOG(ERR, "rte_epoll_event can't be NULL"); @@ -1328,12 +1331,31 @@ eal_epoll_wait(int epfd, struct rte_epoll_event *events, if (epfd == RTE_EPOLL_PER_THREAD) epfd = rte_intr_tls_epfd(); + num = maxevents; + n = RTE_MIN(RTE_DIM(evs), num); + + /* Process events in chunks of MAX_ITER_EVNUM */ + while (1) { - rc = epoll_wait(epfd, evs, maxevents, timeout); + rc = epoll_wait(epfd, evs, n, timeout); if (likely(rc > 0)) { + /* epoll_wait has at least one fd ready to read */ - rc = eal_epoll_process_event(evs, rc, events); - break; + for (i = 0, k = 0; rc > 0;) { + k += rc; + rc = eal_epoll_process_event(evs, rc, + events + i); + i += rc; + + /* + * try to read more events that are already + * available (up to maxevents in total). + */ + n = RTE_MIN(RTE_DIM(evs), num - k); + rc = (n == 0) ? 0 : epoll_wait(epfd, evs, n, 0); + } + return i; + } else if (rc < 0) { if (errno == EINTR) { if (interruptible) -- 2.34.1