I/OAT: Add documentation for the tcp_dma_copybreak sysctl

Signed-off-by: Chris Leech <christopher.leech@intel.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt
index af6a63ab9026..8f6067ea5e3e 100644
--- a/Documentation/networking/ip-sysctl.txt
+++ b/Documentation/networking/ip-sysctl.txt
@@ -433,6 +433,12 @@ tcp_workaround_signed_windows - BOOLEAN
         not receive a window scaling option from them.
         Default: 0
 
+tcp_dma_copybreak - INTEGER
+        Lower limit, in bytes, of the size of socket reads that will be
+        offloaded to a DMA copy engine, if one is present in the system
+        and CONFIG_NET_DMA is enabled.
+        Default: 4096
+
 CIPSOv4 Variables:
 
 cipso_cache_enable - BOOLEAN