From 212e2c1d0cb27f0d1f87b9cc6454b8afbeb2d467 Mon Sep 17 00:00:00 2001 From: Gal Pressman Date: Thu, 29 Apr 2021 09:48:02 +0300 Subject: [PATCH 1/2] rdma: update uapi headers Update rdma_netlink.h file upto kernel commit 6cc9e215eb27 ("RDMA/nldev: Add copy-on-fork attribute to get sys command") Signed-off-by: Gal Pressman Acked-by: Leon Romanovsky Signed-off-by: David Ahern --- rdma/include/uapi/rdma/rdma_netlink.h | 3 +++ 1 file changed, 3 insertions(+) diff --git a/rdma/include/uapi/rdma/rdma_netlink.h b/rdma/include/uapi/rdma/rdma_netlink.h index e161c245..37f583ee 100644 --- a/rdma/include/uapi/rdma/rdma_netlink.h +++ b/rdma/include/uapi/rdma/rdma_netlink.h @@ -546,6 +546,9 @@ enum rdma_nldev_attr { RDMA_NLDEV_ATTR_MIN_RANGE, /* u32 */ RDMA_NLDEV_ATTR_MAX_RANGE, /* u32 */ + + RDMA_NLDEV_SYS_ATTR_COPY_ON_FORK, /* u8 */ + /* * Always the end */ From bce424786969241d9f01913e5b9ed07c6ba74be9 Mon Sep 17 00:00:00 2001 From: Gal Pressman Date: Thu, 29 Apr 2021 09:48:03 +0300 Subject: [PATCH 2/2] rdma: Add copy-on-fork to get sys command The new attribute indicates that the kernel copies DMA pages on fork, hence fork support through madvise and MADV_DONTFORK is not needed. If the attribute is not reported (expected on older kernels), copy-on-fork is disabled. Example: $ rdma sys netns shared copy-on-fork on Signed-off-by: Gal Pressman Acked-by: Leon Romanovsky Signed-off-by: David Ahern --- rdma/sys.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/rdma/sys.c b/rdma/sys.c index 8fb565d7..fd785b25 100644 --- a/rdma/sys.c +++ b/rdma/sys.c @@ -20,6 +20,7 @@ static const char *netns_modes_str[] = { static int sys_show_parse_cb(const struct nlmsghdr *nlh, void *data) { struct nlattr *tb[RDMA_NLDEV_ATTR_MAX] = {}; + bool cof = false; mnl_attr_parse(nlh, 0, rd_attr_cb, tb); @@ -35,9 +36,17 @@ static int sys_show_parse_cb(const struct nlmsghdr *nlh, void *data) else mode_str = "unknown"; - print_color_string(PRINT_ANY, COLOR_NONE, "netns", "netns %s\n", + print_color_string(PRINT_ANY, COLOR_NONE, "netns", "netns %s ", mode_str); } + + if (tb[RDMA_NLDEV_SYS_ATTR_COPY_ON_FORK]) + cof = mnl_attr_get_u8(tb[RDMA_NLDEV_SYS_ATTR_COPY_ON_FORK]); + + print_color_on_off(PRINT_ANY, COLOR_NONE, "copy-on-fork", + "copy-on-fork %s\n", + cof); + return MNL_CB_OK; }