From 3b885787ea4112eaa80945999ea0901bf742707f Mon Sep 17 00:00:00 2001 From: Neil Horman Date: Mon, 12 Oct 2009 13:26:31 -0700 Subject: net: Generalize socket rx gap / receive queue overflow cmsg Create a new socket level option to report number of queue overflows Recently I augmented the AF_PACKET protocol to report the number of frames lost on the socket receive queue between any two enqueued frames. This value was exported via a SOL_PACKET level cmsg. AFter I completed that work it was requested that this feature be generalized so that any datagram oriented socket could make use of this option. As such I've created this patch, It creates a new SOL_SOCKET level option called SO_RXQ_OVFL, which when enabled exports a SOL_SOCKET level cmsg that reports the nubmer of times the sk_receive_queue overflowed between any two given frames. It also augments the AF_PACKET protocol to take advantage of this new feature (as it previously did not touch sk->sk_drops, which this patch uses to record the overflow count). Tested successfully by me. Notes: 1) Unlike my previous patch, this patch simply records the sk_drops value, which is not a number of drops between packets, but rather a total number of drops. Deltas must be computed in user space. 2) While this patch currently works with datagram oriented protocols, it will also be accepted by non-datagram oriented protocols. I'm not sure if thats agreeable to everyone, but my argument in favor of doing so is that, for those protocols which aren't applicable to this option, sk_drops will always be zero, and reporting no drops on a receive queue that isn't used for those non-participating protocols seems reasonable to me. This also saves us having to code in a per-protocol opt in mechanism. 3) This applies cleanly to net-next assuming that commit 977750076d98c7ff6cbda51858bb5a5894a9d9ab (my af packet cmsg patch) is reverted Signed-off-by: Neil Horman Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- arch/ia64/include/asm/socket.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'arch/ia64') diff --git a/arch/ia64/include/asm/socket.h b/arch/ia64/include/asm/socket.h index 0b0d5ff062e5..51427eaa51ba 100644 --- a/arch/ia64/include/asm/socket.h +++ b/arch/ia64/include/asm/socket.h @@ -69,4 +69,6 @@ #define SO_PROTOCOL 38 #define SO_DOMAIN 39 +#define SO_RXQ_OVFL 40 + #endif /* _ASM_IA64_SOCKET_H */ -- cgit v1.2.2 From a2e2725541fad72416326798c2d7fa4dafb7d337 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Mon, 12 Oct 2009 23:40:10 -0700 Subject: net: Introduce recvmmsg socket syscall MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Meaning receive multiple messages, reducing the number of syscalls and net stack entry/exit operations. Next patches will introduce mechanisms where protocols that want to optimize this operation will provide an unlocked_recvmsg operation. This takes into account comments made by: . Paul Moore: sock_recvmsg is called only for the first datagram, sock_recvmsg_nosec is used for the rest. . Caitlin Bestler: recvmmsg now has a struct timespec timeout, that works in the same fashion as the ppoll one. If the underlying protocol returns a datagram with MSG_OOB set, this will make recvmmsg return right away with as many datagrams (+ the OOB one) it has received so far. . Rémi Denis-Courmont & Steven Whitehouse: If we receive N < vlen datagrams and then recvmsg returns an error, recvmmsg will return the successfully received datagrams, store the error and return it in the next call. This paves the way for a subsequent optimization, sk_prot->unlocked_recvmsg, where we will be able to acquire the lock only at batch start and end, not at every underlying recvmsg call. Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: David S. Miller --- arch/ia64/kernel/entry.S | 1 + 1 file changed, 1 insertion(+) (limited to 'arch/ia64') diff --git a/arch/ia64/kernel/entry.S b/arch/ia64/kernel/entry.S index d0e7d37017b4..d75b872ca4dc 100644 --- a/arch/ia64/kernel/entry.S +++ b/arch/ia64/kernel/entry.S @@ -1806,6 +1806,7 @@ sys_call_table: data8 sys_preadv data8 sys_pwritev // 1320 data8 sys_rt_tgsigqueueinfo + data8 sys_recvmmsg .org sys_call_table + 8*NR_syscalls // guard against failures to increase NR_syscalls #endif /* __IA64_ASM_PARAVIRTUALIZED_NATIVE */ -- cgit v1.2.2 From 67ca0e5fa884f483d655ef19f22ad8509138dd3e Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Wed, 14 Oct 2009 13:11:30 -0700 Subject: ia64: Fix up the syscall table for recvmmsg Reported-by: "Tony Luck" Signed-off-by: Arnaldo Carvalho de Melo Acked-by: Tony Luck Signed-off-by: David S. Miller --- arch/ia64/include/asm/unistd.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'arch/ia64') diff --git a/arch/ia64/include/asm/unistd.h b/arch/ia64/include/asm/unistd.h index 5a5347f5c4e4..9c72e36c5281 100644 --- a/arch/ia64/include/asm/unistd.h +++ b/arch/ia64/include/asm/unistd.h @@ -311,11 +311,12 @@ #define __NR_preadv 1319 #define __NR_pwritev 1320 #define __NR_rt_tgsigqueueinfo 1321 +#define __NR_rt_recvmmsg 1322 #ifdef __KERNEL__ -#define NR_syscalls 298 /* length of syscall table */ +#define NR_syscalls 299 /* length of syscall table */ /* * The following defines stop scripts/checksyscalls.sh from complaining about -- cgit v1.2.2