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2017-08-11net: fix compilation when busy poll is not enabledDaniel Borkmann1-6/+6
MIN_NAPI_ID is used in various places outside of CONFIG_NET_RX_BUSY_POLL wrapping, so when it's not set we run into build errors such as: net/core/dev.c: In function 'dev_get_by_napi_id': net/core/dev.c:886:16: error: ‘MIN_NAPI_ID’ undeclared (first use in this function) if (napi_id < MIN_NAPI_ID) ^~~~~~~~~~~ Thus, have MIN_NAPI_ID always defined to fix these errors. Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-24net: Commonize busy polling code to focus on napi_id instead of socketSridhar Samudrala1-5/+15
Move the core functionality in sk_busy_loop() to napi_busy_loop() and make it independent of sk. This enables re-using this function in epoll busy loop implementation. Signed-off-by: Sridhar Samudrala <sridhar.samudrala@intel.com> Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-24net: Track start of busy loop instead of when it should endAlexander Duyck1-30/+38
This patch flips the logic we were using to determine if the busy polling has timed out. The main motivation for this is that we will need to support two different possible timeout values in the future and by recording the start time rather than when we would want to end we can focus on making the end_time specific to the task be it epoll or socket based polling. Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-24net: Change return type of sk_busy_loop from bool to voidAlexander Duyck1-3/+2
checking the return value of sk_busy_loop. As there are only a few consumers of that data, and the data being checked for can be replaced with a check for !skb_queue_empty() we might as well just pull the code out of sk_busy_loop and place it in the spots that actually need it. Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-24net: Only define skb_mark_napi_id in one spot instead of twoAlexander Duyck1-13/+9
Instead of defining two versions of skb_mark_napi_id I think it is more readable to just match the format of the sk_mark_napi_id functions and just wrap the contents of the function instead of defining two versions of the function. This way we can save a few lines of code since we only need 2 of the ifdef/endif but needed 5 for the extra function declaration. Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-24net: Busy polling should ignore sender CPUsAlexander Duyck1-2/+7
This patch is a cleanup/fix for NAPI IDs following the changes that made it so that sender_cpu and napi_id were doing a better job of sharing the same location in the sk_buff. One issue I found is that we weren't validating the napi_id as being valid before we started trying to setup the busy polling. This change corrects that by using the MIN_NAPI_ID value that is now used in both allocating the NAPI IDs, as well as validating them. Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2017-03-02sched/headers: Prepare to move signal wakeup & sigpending methods from ↵Ingo Molnar1-0/+1
<linux/sched.h> into <linux/sched/signal.h> Fix up affected files that include this signal functionality via sched.h. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-03-02sched/headers: Prepare for new header dependencies before moving code to ↵Ingo Molnar1-0/+1
<linux/sched/clock.h> We are going to split <linux/sched/clock.h> out of <linux/sched.h>, which will have to be picked up from other headers and .c files. Create a trivial placeholder <linux/sched/clock.h> file that just maps to <linux/sched.h> to make this patch obviously correct and bisectable. Include the new header in the files that are going to need it. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-02-13net: busy-poll: remove LL_FLUSH_FAILED and LL_FLUSH_BUSYEric Dumazet1-4/+0
Commit 79e7fff47b7b ("net: remove support for per driver ndo_busy_poll()") made them obsolete. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-18udp: enable busy polling for all socketsEric Dumazet1-9/+19
UDP busy polling is restricted to connected UDP sockets. This is because sk_busy_loop() only takes care of one NAPI context. There are cases where it could be extended. 1) Some hosts receive traffic on a single NIC, with one RX queue. 2) Some applications use SO_REUSEPORT and associated BPF filter to split the incoming traffic on one UDP socket per RX queue/thread/cpu 3) Some UDP sockets are used to send/receive traffic for one flow, but they do not bother with connect() This patch records the napi_id of first received skb, giving more reach to busy polling. Tested: lpaa23:~# echo 70 >/proc/sys/net/core/busy_read lpaa24:~# echo 70 >/proc/sys/net/core/busy_read lpaa23:~# for f in `seq 1 10`; do ./super_netperf 1 -H lpaa24 -t UDP_RR -l 5; done Before patch : 27867 28870 37324 41060 41215 36764 36838 44455 41282 43843 After patch : 73920 73213 70147 74845 71697 68315 68028 75219 70082 73707 Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-11-16net: busy-poll: remove need_resched() from sk_can_busy_loop()Eric Dumazet1-3/+2
Now sk_busy_loop() can schedule by itself, we can remove need_resched() check from sk_can_busy_loop() Also add a const to its struct sock parameter. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Willem de Bruijn <willemb@google.com> Cc: Adam Belay <abelay@google.com> Cc: Tariq Toukan <tariqt@mellanox.com> Cc: Yuval Mintz <Yuval.Mintz@cavium.com> Cc: Ariel Elior <ariel.elior@cavium.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-11-18net: un-inline sk_busy_loop()Eric Dumazet1-44/+1
There is really little gain from inlining this big function. We'll soon make it even bigger in following patches. This means we no longer need to export napi_by_id() Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-01-13sched, net: Fixup busy_loop_us_clock()Peter Zijlstra1-18/+1
The only valid use of preempt_enable_no_resched() is if the very next line is schedule() or if we know preemption cannot actually be enabled by that statement due to known more preempt_count 'refs'. This busy_poll stuff looks to be completely and utterly broken, sched_clock() can return utter garbage with interrupts enabled (rare but still) and it can drift unbounded between CPUs. This means that if you get preempted/migrated and your new CPU is years behind on the previous CPU we get to busy spin for a _very_ long time. There is a _REASON_ sched_clock() warns about preemptability - papering over it with a preempt_disable()/preempt_enable_no_resched() is just terminal brain damage on so many levels. Replace sched_clock() usage with local_clock() which has a bounded drift between CPUs (<2 jiffies). There is a further problem with the entire busy wait poll thing in that the spin time is additive to the syscall timeout, not inclusive. Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Cc: David S. Miller <davem@davemloft.net> Cc: rui.zhang@intel.com Cc: jacob.jun.pan@linux.intel.com Cc: Mike Galbraith <bitbucket@online.de> Cc: hpa@zytor.com Cc: Arjan van de Ven <arjan@linux.intel.com> Cc: lenb@kernel.org Cc: rjw@rjwysocki.net Cc: Eliezer Tamir <eliezer.tamir@linux.intel.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Andrew Morton <akpm@linux-foundation.org> Link: http://lkml.kernel.org/r/20131119151338.GF3694@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2013-08-28net: add cpu_relax to busy poll loopEliezer Tamir1-0/+1
Add a cpu_relaxt to sk_busy_loop. Julie Cummings reported performance issues when hyperthreading is on. Arjan van de Ven observed that we should have a cpu_relax() in the busy poll loop. Reported-by: Julie Cummings <julie.a.cummings@intel.com> Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-09net: rename busy poll MIB counterEliezer Tamir1-1/+1
Rename mib counter from "low latency" to "busy poll" v1 also moved the counter to the ip MIB (suggested by Shawn Bohrer) Eric Dumazet suggested that the current location is better. So v2 just renames the counter to fit the new naming convention. Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-04busy_poll: cleanup do-nothing placeholdersEliezer Tamir1-5/+0
When renaming ll_poll to busy poll, I introduced a typo in the name of the do-nothing placeholder for sk_busy_loop and called it sk_busy_poll. This broke compile when busy poll was not configured. Cong Wang submitted a patch to fixed that. This patch removes the now redundant, misspelled placeholder. Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-01net: rename CONFIG_NET_LL_RX_POLL to CONFIG_NET_RX_BUSY_POLLCong Wang1-3/+3
Eliezer renames several *ll_poll to *busy_poll, but forgets CONFIG_NET_LL_RX_POLL, so in case of confusion, rename it too. Cc: Eliezer Tamir <eliezer.tamir@linux.intel.com> Cc: David S. Miller <davem@davemloft.net> Signed-off-by: Cong Wang <amwang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-01net: fix a compile error when CONFIG_NET_LL_RX_POLL is not setCong Wang1-0/+5
When CONFIG_NET_LL_RX_POLL is not set, I got: net/socket.c: In function ‘sock_poll’: net/socket.c:1165:4: error: implicit declaration of function ‘sk_busy_loop’ [-Werror=implicit-function-declaration] Fix this by adding a nop when !CONFIG_NET_LL_RX_POLL. Cc: Eliezer Tamir <eliezer.tamir@linux.intel.com> Cc: David S. Miller <davem@davemloft.net> Signed-off-by: Cong Wang <amwang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-10net: rename busy poll socket op and globalsEliezer Tamir1-4/+4
Rename LL_SO to BUSY_POLL_SO Rename sysctl_net_ll_{read,poll} to sysctl_busy_{read,poll} Fix up users of these variables. Fix documentation for sysctl. a patch for the socket.7 man page will follow separately, because of limitations of my mail setup. Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-10net: rename ll methods to busy-pollEliezer Tamir1-10/+12
Rename ndo_ll_poll to ndo_busy_poll. Rename sk_mark_ll to sk_mark_napi_id. Rename skb_mark_ll to skb_mark_napi_id. Correct all useres of these functions. Update comments and defines in include/net/busy_poll.h Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-07-10net: rename include/net/ll_poll.h to include/net/busy_poll.hEliezer Tamir1-0/+183
Rename the file and correct all the places where it is included. Signed-off-by: Eliezer Tamir <eliezer.tamir@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net>