Re: [PATCH net-next v6 6/7] selftests: net: Add busy_poll_test

On 11/04, Joe Damato wrote:

Add an epoll busy poll test using netdevsim.

This test is comprised of:

• busy_poller (via busy_poller.c)
• busy_poll_test.sh which loads netdevsim, sets up network namespaces, and runs busy_poller to receive data and socat to send data.

The selftest tests two different scenarios:

• busy poll (the pre-existing version in the kernel)
• busy poll with suspend enabled (what this series adds)

The data transmit is a 1MiB temporary file generated from /dev/urandom and the test is considered passing if the md5sum of the input file to socat matches the md5sum of the output file from busy_poller.

netdevsim was chosen instead of veth due to netdevsim's support for netdev-genl.

For now, this test uses the functionality that netdevsim provides. In the future, perhaps netdevsim can be extended to emulate device IRQs to more thoroughly test all pre-existing kernel options (like defer_hard_irqs) and suspend.

Signed-off-by: Joe Damato jdamato@fastly.com Co-developed-by: Martin Karsten mkarsten@uwaterloo.ca Signed-off-by: Martin Karsten mkarsten@uwaterloo.ca

---

v5:

• Updated commit message to replace netcat with socat and fixed misspelling of netdevsim. No functional/code changes.

v4:

• Updated busy_poll_test.sh:
  • use socat instead of nc
  • drop cli.py usage from the script
  • removed check_ynl
• Updated busy_poller.c:
  • use netlink to configure napi parameters

v3:

• New in v3

tools/testing/selftests/net/.gitignore | 1 + tools/testing/selftests/net/Makefile | 3 +- tools/testing/selftests/net/busy_poll_test.sh | 164 +++++++++ tools/testing/selftests/net/busy_poller.c | 328 ++++++++++++++++++ 4 files changed, 495 insertions(+), 1 deletion(-) create mode 100755 tools/testing/selftests/net/busy_poll_test.sh create mode 100644 tools/testing/selftests/net/busy_poller.c

diff --git a/tools/testing/selftests/net/.gitignore b/tools/testing/selftests/net/.gitignore index 217d8b7a7365..85b0c4a2179f 100644 --- a/tools/testing/selftests/net/.gitignore +++ b/tools/testing/selftests/net/.gitignore @@ -2,6 +2,7 @@ bind_bhash bind_timewait bind_wildcard +busy_poller cmsg_sender diag_uid epoll_busy_poll diff --git a/tools/testing/selftests/net/Makefile b/tools/testing/selftests/net/Makefile index 26a4883a65c9..3ccfe454db1a 100644 --- a/tools/testing/selftests/net/Makefile +++ b/tools/testing/selftests/net/Makefile @@ -96,9 +96,10 @@ TEST_PROGS += fdb_flush.sh TEST_PROGS += fq_band_pktlimit.sh TEST_PROGS += vlan_hw_filter.sh TEST_PROGS += bpf_offload.py +TEST_PROGS += busy_poll_test.sh # YNL files, must be before "include ..lib.mk" -YNL_GEN_FILES := ncdevmem +YNL_GEN_FILES := ncdevmem busy_poller TEST_GEN_FILES += $(YNL_GEN_FILES) TEST_FILES := settings diff --git a/tools/testing/selftests/net/busy_poll_test.sh b/tools/testing/selftests/net/busy_poll_test.sh new file mode 100755 index 000000000000..ffc74bc62e5a --- /dev/null +++ b/tools/testing/selftests/net/busy_poll_test.sh @@ -0,0 +1,164 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0-only +source net_helper.sh

+NSIM_DEV_1_ID=$((256 + RANDOM % 256)) +NSIM_DEV_1_SYS=/sys/bus/netdevsim/devices/netdevsim$NSIM_DEV_1_ID +NSIM_DEV_2_ID=$((512 + RANDOM % 256)) +NSIM_DEV_2_SYS=/sys/bus/netdevsim/devices/netdevsim$NSIM_DEV_2_ID

+NSIM_DEV_SYS_NEW=/sys/bus/netdevsim/new_device +NSIM_DEV_SYS_DEL=/sys/bus/netdevsim/del_device +NSIM_DEV_SYS_LINK=/sys/bus/netdevsim/link_device +NSIM_DEV_SYS_UNLINK=/sys/bus/netdevsim/unlink_device

+setup_ns() +{

• set -e
• ip netns add nssv
• ip netns add nscl
• NSIM_DEV_1_NAME=$(find $NSIM_DEV_1_SYS/net -maxdepth 1 -type d ! \

• -path $NSIM_DEV_1_SYS/net -exec basename {} \;)
  

• NSIM_DEV_2_NAME=$(find $NSIM_DEV_2_SYS/net -maxdepth 1 -type d ! \

• -path $NSIM_DEV_2_SYS/net -exec basename {} \;)
  

• # ensure the server has 1 queue
• ethtool -L $NSIM_DEV_1_NAME combined 1 2>/dev/null
• ip link set $NSIM_DEV_1_NAME netns nssv
• ip link set $NSIM_DEV_2_NAME netns nscl
• ip netns exec nssv ip addr add '192.168.1.1/24' dev $NSIM_DEV_1_NAME
• ip netns exec nscl ip addr add '192.168.1.2/24' dev $NSIM_DEV_2_NAME
• ip netns exec nssv ip link set dev $NSIM_DEV_1_NAME up
• ip netns exec nscl ip link set dev $NSIM_DEV_2_NAME up
• set +e

+}

+cleanup_ns() +{

• ip netns del nscl
• ip netns del nssv

+}

+test_busypoll() +{

• tmp_file=$(mktemp)
• out_file=$(mktemp)
• # fill a test file with random data
• dd if=/dev/urandom of=${tmp_file} bs=1M count=1 2> /dev/null
• timeout -k 1s 30s ip netns exec nssv ./busy_poller -p48675 -b192.168.1.1 -m8 -u0 -P1 -g16 -i${NSIM_DEV_1_IFIDX} -o${out_file}&
• wait_local_port_listen nssv 48675 tcp
• ip netns exec nscl socat -u $tmp_file TCP:192.168.1.1:48675
• wait
• tmp_file_md5sum=$(md5sum $tmp_file | cut -f1 -d' ')
• out_file_md5sum=$(md5sum $out_file | cut -f1 -d' ')
• if [ "$tmp_file_md5sum" = "$out_file_md5sum" ]; then

• res=0
  

• else

• echo "md5sum mismatch"
  

• echo "input file md5sum: ${tmp_file_md5sum}";
  

• echo "output file md5sum: ${out_file_md5sum}";
  

• res=1
  

• fi
• rm $out_file $tmp_file
• return $res

+}

+test_busypoll_with_suspend() +{

• tmp_file=$(mktemp)
• out_file=$(mktemp)
• # fill a test file with random data
• dd if=/dev/urandom of=${tmp_file} bs=1M count=1 2> /dev/null
• timeout -k 1s 30s ip netns exec nssv ./busy_poller -p48675 -b192.168.1.1 -m8 -u0 -P1 -g16 -d100 -r50000 -s20000000 -i${NSIM_DEV_1_IFIDX} -o${out_file}&
• wait_local_port_listen nssv 48675 tcp
• ip netns exec nscl socat -u $tmp_file TCP:192.168.1.1:48675
• wait
• tmp_file_md5sum=$(md5sum $tmp_file | cut -f1 -d' ')
• out_file_md5sum=$(md5sum $out_file | cut -f1 -d' ')
• if [ "$tmp_file_md5sum" = "$out_file_md5sum" ]; then

• res=0
  

• else

• echo "md5sum mismatch"
  

• echo "input file md5sum: ${tmp_file_md5sum}";
  

• echo "output file md5sum: ${out_file_md5sum}";
  

• res=1
  

• fi
• rm $out_file $tmp_file
• return $res

+}

+### +### Code start +###

+modprobe netdevsim

+# linking

+echo $NSIM_DEV_1_ID > $NSIM_DEV_SYS_NEW +echo $NSIM_DEV_2_ID > $NSIM_DEV_SYS_NEW +udevadm settle

+setup_ns

+NSIM_DEV_1_FD=$((256 + RANDOM % 256)) +exec {NSIM_DEV_1_FD}</var/run/netns/nssv +NSIM_DEV_1_IFIDX=$(ip netns exec nssv cat /sys/class/net/$NSIM_DEV_1_NAME/ifindex)

+NSIM_DEV_2_FD=$((256 + RANDOM % 256)) +exec {NSIM_DEV_2_FD}</var/run/netns/nscl +NSIM_DEV_2_IFIDX=$(ip netns exec nscl cat /sys/class/net/$NSIM_DEV_2_NAME/ifindex)

+echo "$NSIM_DEV_1_FD:$NSIM_DEV_1_IFIDX $NSIM_DEV_2_FD:$NSIM_DEV_2_IFIDX" > $NSIM_DEV_SYS_LINK +if [ $? -ne 0 ]; then

• echo "linking netdevsim1 with netdevsim2 should succeed"
• cleanup_ns
• exit 1

+fi

+test_busypoll +if [ $? -ne 0 ]; then

• echo "test_busypoll failed"
• cleanup_ns
• exit 1

+fi

+test_busypoll_with_suspend +if [ $? -ne 0 ]; then

• echo "test_busypoll_with_suspend failed"
• cleanup_ns
• exit 1

+fi

+echo "$NSIM_DEV_1_FD:$NSIM_DEV_1_IFIDX" > $NSIM_DEV_SYS_UNLINK

+echo $NSIM_DEV_2_ID > $NSIM_DEV_SYS_DEL

+cleanup_ns

+modprobe -r netdevsim

+exit 0 diff --git a/tools/testing/selftests/net/busy_poller.c b/tools/testing/selftests/net/busy_poller.c new file mode 100644 index 000000000000..8d8aa9e5939a --- /dev/null +++ b/tools/testing/selftests/net/busy_poller.c @@ -0,0 +1,328 @@ +// SPDX-License-Identifier: GPL-2.0 +#include <assert.h> +#include <errno.h> +#include <error.h> +#include <fcntl.h> +#include <inttypes.h> +#include <limits.h> +#include <stdlib.h> +#include <stdio.h> +#include <string.h> +#include <unistd.h>

+#include <arpa/inet.h> +#include <netinet/in.h>

+#include <sys/ioctl.h> +#include <sys/epoll.h> +#include <sys/socket.h> +#include <sys/types.h>

+#include <linux/netlink.h> +#include <linux/genetlink.h> +#include "netdev-user.h" +#include <ynl.h>

+/* if the headers haven't been updated, we need to define some things */ +#if !defined(EPOLL_IOC_TYPE) +struct epoll_params {

• uint32_t busy_poll_usecs;
• uint16_t busy_poll_budget;
• uint8_t prefer_busy_poll;
• /* pad the struct to a multiple of 64bits */
• uint8_t __pad;

+};

+#define EPOLL_IOC_TYPE 0x8A +#define EPIOCSPARAMS _IOW(EPOLL_IOC_TYPE, 0x01, struct epoll_params) +#define EPIOCGPARAMS _IOR(EPOLL_IOC_TYPE, 0x02, struct epoll_params) +#endif

+static uint32_t cfg_port = 8000; +static struct in_addr cfg_bind_addr = { .s_addr = INADDR_ANY }; +static char *cfg_outfile; +static int cfg_max_events = 8; +static int cfg_ifindex;

+/* busy poll params */ +static uint32_t cfg_busy_poll_usecs; +static uint16_t cfg_busy_poll_budget; +static uint8_t cfg_prefer_busy_poll;

+/* IRQ params */ +static uint32_t cfg_defer_hard_irqs; +static uint64_t cfg_gro_flush_timeout; +static uint64_t cfg_irq_suspend_timeout;

+static void usage(const char *filepath) +{

• error(1, 0,

•      "Usage: %s -p<port> -b<addr> -m<max_events> -u<busy_poll_usecs> -P<prefer_busy_poll> -g<busy_poll_budget> -o<outfile> -d<defer_hard_irqs> -r<gro_flush_timeout> -s<irq_suspend_timeout> -i<ifindex>",
  

•      filepath);
  

+}

+static void parse_opts(int argc, char **argv) +{

• int ret;
• int c;
• if (argc <= 1)

• usage(argv[0]);
  

• while ((c = getopt(argc, argv, "p:m:b:u:P:g:o:d:r:s:i:")) != -1) {

• switch (c) {
  

• case 'u':
  

• 	cfg_busy_poll_usecs = strtoul(optarg, NULL, 0);
  

• 	if (cfg_busy_poll_usecs == ULONG_MAX ||
  

• 	    cfg_busy_poll_usecs > UINT32_MAX)
  

• 		error(1, ERANGE, "busy_poll_usecs too large");
  

• 	break;
  

• case 'P':
  

• 	cfg_prefer_busy_poll = strtoul(optarg, NULL, 0);
  

• 	if (cfg_prefer_busy_poll == ULONG_MAX ||
  

• 	    cfg_prefer_busy_poll > 1)
  

• 		error(1, ERANGE,
  

• 		      "prefer busy poll should be 0 or 1");
  

• 	break;
  

• case 'g':
  

• 	cfg_busy_poll_budget = strtoul(optarg, NULL, 0);
  

• 	if (cfg_busy_poll_budget == ULONG_MAX ||
  

• 	    cfg_busy_poll_budget > UINT16_MAX)
  

• 		error(1, ERANGE,
  

• 		      "busy poll budget must be [0, UINT16_MAX]");
  

• 	break;
  

• case 'p':
  

• 	cfg_port = strtoul(optarg, NULL, 0);
  

• 	if (cfg_port > UINT16_MAX)
  

• 		error(1, ERANGE, "port must be <= 65535");
  

• 	break;
  

• case 'b':
  

• 	ret = inet_aton(optarg, &cfg_bind_addr);
  

• 	if (ret == 0)
  

• 		error(1, errno,
  

• 		      "bind address %s invalid", optarg);
  

• 	break;
  

• case 'o':
  

• 	cfg_outfile = strdup(optarg);
  

• 	if (!cfg_outfile)
  

• 		error(1, 0, "outfile invalid");
  

• 	break;
  

• case 'm':
  

• 	cfg_max_events = strtol(optarg, NULL, 0);
  

• 	if (cfg_max_events == LONG_MIN ||
  

• 	    cfg_max_events == LONG_MAX ||
  

• 	    cfg_max_events <= 0)
  

• 		error(1, ERANGE,
  

• 		      "max events must be > 0 and < LONG_MAX");
  

• 	break;
  

• case 'd':
  

• 	cfg_defer_hard_irqs = strtoul(optarg, NULL, 0);
  

• 	if (cfg_defer_hard_irqs == ULONG_MAX ||
  

• 	    cfg_defer_hard_irqs > INT32_MAX)
  

• 		error(1, ERANGE,
  

• 		      "defer_hard_irqs must be <= INT32_MAX");
  

• 	break;
  

• case 'r':
  

• 	cfg_gro_flush_timeout = strtoull(optarg, NULL, 0);
  

• 	if (cfg_gro_flush_timeout == ULLONG_MAX)
  

• 		error(1, ERANGE,
  

• 		      "gro_flush_timeout must be < ULLONG_MAX");
  

• 	break;
  

• case 's':
  

• 	cfg_irq_suspend_timeout = strtoull(optarg, NULL, 0);
  

• 	if (cfg_irq_suspend_timeout == ULLONG_MAX)
  

• 		error(1, ERANGE,
  

• 		      "irq_suspend_timeout must be < ULLONG_MAX");
  

• 	break;
  

• case 'i':
  

• 	cfg_ifindex = strtoul(optarg, NULL, 0);
  

• 	if (cfg_ifindex == ULONG_MAX)
  

• 		error(1, ERANGE,
  

• 		      "ifindex must be < ULONG_MAX");
  

• 	break;
  

• }
  

• }
• if (!cfg_ifindex)

• usage(argv[0]);
  

• if (optind != argc)

• usage(argv[0]);
  

+}

+static void epoll_ctl_add(int epfd, int fd, uint32_t events) +{

• struct epoll_event ev;
• ev.events = events;
• ev.data.fd = fd;
• if (epoll_ctl(epfd, EPOLL_CTL_ADD, fd, &ev) == -1)

• error(1, errno, "epoll_ctl add fd: %d", fd);
  

+}

+static void setnonblock(int sockfd) +{

• int flags;
• flags = fcntl(sockfd, F_GETFL, 0);
• if (fcntl(sockfd, F_SETFL, flags | O_NONBLOCK) == -1)

• error(1, errno, "unable to set socket to nonblocking mode");
  

+}

+static void write_chunk(int fd, char *buf, ssize_t buflen) +{

• ssize_t remaining = buflen;
• char *buf_offset = buf;
• ssize_t writelen = 0;
• ssize_t write_result;
• while (writelen < buflen) {

• write_result = write(fd, buf_offset, remaining);
  

• if (write_result == -1)
  

• 	error(1, errno, "unable to write data to outfile");
  

• writelen += write_result;
  

• remaining -= write_result;
  

• buf_offset += write_result;
  

• }

+}

+static void setup_queue(void) +{

• struct netdev_napi_get_list *napi_list = NULL;
• struct netdev_napi_get_req_dump *req = NULL;
• struct netdev_napi_set_req *set_req = NULL;
• struct ynl_sock *ys;
• struct ynl_error yerr;
• uint32_t napi_id;
• ys = ynl_sock_create(&ynl_netdev_family, &yerr);
• if (!ys)

• error(1, 0, "YNL: %s", yerr.msg);
  

• req = netdev_napi_get_req_dump_alloc();
• netdev_napi_get_req_dump_set_ifindex(req, cfg_ifindex);
• napi_list = netdev_napi_get_dump(ys, req);
• /* assume there is 1 NAPI configured and take the first */
• if (napi_list->obj._present.id)

• napi_id = napi_list->obj.id;
  

• else

• error(1, 0, "napi ID not present?");
  

• set_req = netdev_napi_set_req_alloc();
• netdev_napi_set_req_set_id(set_req, napi_id);
• netdev_napi_set_req_set_defer_hard_irqs(set_req, cfg_defer_hard_irqs);
• netdev_napi_set_req_set_gro_flush_timeout(set_req,

• 				  cfg_gro_flush_timeout);
  

• netdev_napi_set_req_set_irq_suspend_timeout(set_req,

• 				    cfg_irq_suspend_timeout);
  

• if (netdev_napi_set(ys, set_req))

• error(1, 0, "can't set NAPI params: %s\n", yerr.msg);
  

• netdev_napi_get_list_free(napi_list);
• netdev_napi_get_req_dump_free(req);
• netdev_napi_set_req_free(set_req);
• ynl_sock_destroy(ys);

+}

+static void run_poller(void) +{

• struct epoll_event events[cfg_max_events];
• struct epoll_params epoll_params = {0};
• struct sockaddr_in server_addr;
• int i, epfd, nfds;
• ssize_t readlen;
• int outfile_fd;
• char buf[1024];
• int sockfd;
• int conn;
• int val;

[..]

• outfile_fd = open(cfg_outfile, O_WRONLY | O_CREAT, 0644);
• if (outfile_fd == -1)

• error(1, errno, "unable to open outfile: %s", cfg_outfile);
  

Any reason you're not printing to stdout? And then redirect it to a file in the shell script if needed. Lets you save some code on open/close and flag parsing :-p But I guess can keep it since you already have it all working.

Acked-by: Stanislav Fomichev sdf@fomichev.me