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2016-09-30x86, locking/spinlocks: Remove ticket (spin)lock implementationPeter Zijlstra
We've unconditionally used the queued spinlock for many releases now. Its time to remove the old ticket lock code. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Waiman Long <waiman.long@hpe.com> Cc: Waiman.Long@hpe.com Cc: david.vrabel@citrix.com Cc: dhowells@redhat.com Cc: pbonzini@redhat.com Cc: xen-devel@lists.xenproject.org Link: http://lkml.kernel.org/r/20160518184302.GO3193@twins.programming.kicks-ass.net Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-30Merge branch 'linus' into locking/core, to pick up fixesIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-30sched/core: Replace sd_busy/nr_busy_cpus with sched_domain_sharedPeter Zijlstra
Move the nr_busy_cpus thing from its hacky sd->parent->groups->sgc location into the much more natural sched_domain_shared location. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: 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>
2016-09-30sched/core: Introduce 'struct sched_domain_shared'Peter Zijlstra
Since struct sched_domain is strictly per cpu; introduce a structure that is shared between all 'identical' sched_domains. Limit to SD_SHARE_PKG_RESOURCES domains for now, as we'll only use it for shared cache state; if another use comes up later we can easily relax this. While the sched_group's are normally shared between CPUs, these are not natural to use when we need some shared state on a domain level -- since that would require the domain to have a parent, which is not a given. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: 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>
2016-09-30sched/core: Restructure destroy_sched_domain()Peter Zijlstra
There is no point in doing a call_rcu() for each domain, only do a callback for the root sched domain and clean up the entire set in one go. Also make the entire call chain be called destroy_sched_domain*() to remove confusion with the free_sched_domains() call, which does an entirely different thing. Both cpu_attach_domain() callers of destroy_sched_domain() can live without the call_rcu() because at those points the sched_domain hasn't been published yet. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: 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>
2016-09-30sched/core: Remove unused @cpu argument from destroy_sched_domain*()Peter Zijlstra
Small cleanup; nothing uses the @cpu argument so make it go away. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: 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>
2016-09-30sched/wait: Introduce init_wait_entry()Oleg Nesterov
The partial initialization of wait_queue_t in prepare_to_wait_event() looks ugly. This was done to shrink .text, but we can simply add the new helper which does the full initialization and shrink the compiled code a bit more. And. This way prepare_to_wait_event() can have more users. In particular we are ready to remove the signal_pending_state() checks from wait_bit_action_f helpers and change __wait_on_bit_lock() to use prepare_to_wait_event(). Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Bart Van Assche <bvanassche@acm.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Neil Brown <neilb@suse.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20160906140055.GA6167@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-30sched/wait: Avoid abort_exclusive_wait() in __wait_on_bit_lock()Oleg Nesterov
__wait_on_bit_lock() doesn't need abort_exclusive_wait() too. Right now it can't use prepare_to_wait_event() (see the next change), but it can do the additional finish_wait() if action() fails. abort_exclusive_wait() no longer has callers, remove it. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Bart Van Assche <bvanassche@acm.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Neil Brown <neilb@suse.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20160906140053.GA6164@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-30sched/wait: Avoid abort_exclusive_wait() in ___wait_event()Oleg Nesterov
___wait_event() doesn't really need abort_exclusive_wait(), we can simply change prepare_to_wait_event() to remove the waiter from q->task_list if it was interrupted. This simplifies the code/logic, and this way prepare_to_wait_event() can have more users, see the next change. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Bart Van Assche <bvanassche@acm.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Neil Brown <neilb@suse.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20160908164815.GA18801@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org> -- include/linux/wait.h | 7 +------ kernel/sched/wait.c | 35 +++++++++++++++++++++++++---------- 2 files changed, 26 insertions(+), 16 deletions(-)
2016-09-30sched/wait: Fix abort_exclusive_wait(), it should pass TASK_NORMAL to wake_up()Oleg Nesterov
Otherwise this logic only works if mode is "compatible" with another exclusive waiter. If some wq has both TASK_INTERRUPTIBLE and TASK_UNINTERRUPTIBLE waiters, abort_exclusive_wait() won't wait an uninterruptible waiter. The main user is __wait_on_bit_lock() and currently it is fine but only because TASK_KILLABLE includes TASK_UNINTERRUPTIBLE and we do not have lock_page_interruptible() yet. Just use TASK_NORMAL and remove the "mode" arg from abort_exclusive_wait(). Yes, this means that (say) wake_up_interruptible() can wake up the non- interruptible waiter(s), but I think this is fine. And in fact I think that abort_exclusive_wait() must die, see the next change. Signed-off-by: Oleg Nesterov <oleg@redhat.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Al Viro <viro@ZenIV.linux.org.uk> Cc: Bart Van Assche <bvanassche@acm.org> Cc: Johannes Weiner <hannes@cmpxchg.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Neil Brown <neilb@suse.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20160906140047.GA6157@redhat.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-30sched/fair: Fix fixed point arithmetic width for shares and effective loadDietmar Eggemann
Since commit: 2159197d6677 ("sched/core: Enable increased load resolution on 64-bit kernels") we now have two different fixed point units for load: - 'shares' in calc_cfs_shares() has 20 bit fixed point unit on 64-bit kernels. Therefore use scale_load() on MIN_SHARES. - 'wl' in effective_load() has 10 bit fixed point unit. Therefore use scale_load_down() on tg->shares which has 20 bit fixed point unit on 64-bit kernels. Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1471874441-24701-1-git-send-email-dietmar.eggemann@arm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-30sched/core, x86/topology: Fix NUMA in package topology bugTim Chen
Current code can call set_cpu_sibling_map() and invoke sched_set_topology() more than once (e.g. on CPU hot plug). When this happens after sched_init_smp() has been called, we lose the NUMA topology extension to sched_domain_topology in sched_init_numa(). This results in incorrect topology when the sched domain is rebuilt. This patch fixes the bug and issues warning if we call sched_set_topology() after sched_init_smp(). Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com> Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: 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: bp@suse.de Cc: jolsa@redhat.com Cc: rjw@rjwysocki.net Link: http://lkml.kernel.org/r/1474485552-141429-2-git-send-email-srinivas.pandruvada@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-30Merge branch 'linus' into sched/core, to pick up fixesIngo Molnar
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-30softirq: Let ksoftirqd do its jobEric Dumazet
A while back, Paolo and Hannes sent an RFC patch adding threaded-able napi poll loop support : (https://patchwork.ozlabs.org/patch/620657/) The problem seems to be that softirqs are very aggressive and are often handled by the current process, even if we are under stress and that ksoftirqd was scheduled, so that innocent threads would have more chance to make progress. This patch makes sure that if ksoftirq is running, we let it perform the softirq work. Jonathan Corbet summarized the issue in https://lwn.net/Articles/687617/ Tested: - NIC receiving traffic handled by CPU 0 - UDP receiver running on CPU 0, using a single UDP socket. - Incoming flood of UDP packets targeting the UDP socket. Before the patch, the UDP receiver could almost never get CPU cycles and could only receive ~2,000 packets per second. After the patch, CPU cycles are split 50/50 between user application and ksoftirqd/0, and we can effectively read ~900,000 packets per second, a huge improvement in DOS situation. (Note that more packets are now dropped by the NIC itself, since the BH handlers get less CPU cycles to drain RX ring buffer) Since the load runs in well identified threads context, an admin can more easily tune process scheduling parameters if needed. Reported-by: Paolo Abeni <pabeni@redhat.com> Reported-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: David Miller <davem@davemloft.net> Cc: Hannes Frederic Sowa <hannes@redhat.com> Cc: Jesper Dangaard Brouer <jbrouer@redhat.com> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/1472665349.14381.356.camel@edumazet-glaptop3.roam.corp.google.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-30m68k: Migrate exception table users off module.h and onto extable.hPaul Gortmaker
This file was only including module.h for exception table related functions. We've now separated that content out into its own file "extable.h" so now move over to that and avoid all the extra header content in module.h that we don't really need to compile this. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
2016-09-30rxrpc: Actually display the tx_data trace retransmission noteDavid Howells
Actually display in the tx_data trace the retransmission note added in a previous patch. Signed-off-by: David Howells <dhowells@redhat.com>
2016-09-30s390/con3270: fix insufficient space paddingSascha Silbe
con3270 contains an optimisation that reduces the amount of data to be transmitted to the 3270 terminal by putting a Repeat to Address (RA) order into the data stream. The RA order itself takes up space, so con3270 only uses it if there's enough space left in the line buffer. Otherwise it just pads out the line manually. For lines that were _just_ short enough that the RA order still fit in the line buffer, the line was instead padded with an insufficient amount of spaces. This was caused by examining the size of the allocated line buffer rather than the length of the string to be displayed. For con3270_cline_end(), we just compare against the line length. For con3270_update_string() however that isn't available anymore, so we check whether the Repeat to Address order is present. Fixes: f51320a5 ("[PATCH] s390: new 3270 driver.") (tglx/history.git) Tested-by: Jing Liu <liujbjl@linux.vnet.ibm.com> Tested-by: Yang Chen <bjcyang@linux.vnet.ibm.com> Signed-off-by: Sascha Silbe <silbe@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-09-30s390/con3270: fix use of uninitialised dataSascha Silbe
con3270 contains an optimisation that reduces the amount of data to be transmitted to the 3270 terminal by putting a Repeat to Address (RA) order into the data stream. The RA order itself takes up space, so con3270 only uses it if there's enough space left in the line buffer. Otherwise it just pads out the line manually. For lines too long to include the RA order, one byte was left uninitialised. This was caused by an off-by-one bug in the loop that pads out the line. Since the buffer is allocated from a common pool, the single byte left uninitialised contained some previous buffer content. Usually this was just a space or some character (which can result in clutter but is otherwise harmless). Sometimes, however, it was a Repeat to Address order, messing up the entire screen layout and causing the display to send the entire buffer content on every keystroke. Fixes: f51320a5 ("[PATCH] s390: new 3270 driver.") (tglx/history.git) Reported-by: Liu Jing <liujbjl@linux.vnet.ibm.com> Tested-by: Jing Liu <liujbjl@linux.vnet.ibm.com> Tested-by: Yang Chen <bjcyang@linux.vnet.ibm.com> Signed-off-by: Sascha Silbe <silbe@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-09-30MAINTAINERS: update DASD maintainerStefan Haberland
Signed-off-by: Stefan Haberland <sth@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-09-30s390/cio: fix accidental interrupt enabling during resumeSebastian Ott
Since commit 9f3d6d7 chsc_get_channel_measurement_chars is called with interrupts disabled during resume from hibernate. Since this function used spin_unlock_irq, interrupts have been enabled accidentally. Fix this by using the irqsave variant. Since we can't guarantee the IRQ-enablement state for all (future/ external) callers, change the locking in related functions to prevent similar bugs in the future. Fixes: 9f3d6d7 ("s390/cio: update measurement characteristics") Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com> Reviewed-by: Peter Oberparleiter <oberpar@linux.vnet.ibm.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2016-09-30mlx5: Add ndo_poll_controller() implementationCalvin Owens
This implements ndo_poll_controller in net_device_ops callbacks for mlx5, which is necessary to use netconsole with this driver. Acked-By: Saeed Mahameed <saeedm@mellanox.com> Signed-off-by: Calvin Owens <calvinowens@fb.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-30nfp: bpf: zero extend 4 byte context loadsJakub Kicinski
Set upper 32 bits of destination register to zeros after load from the context structure. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-30sctp: fix the issue sctp_diag uses lock_sock in rcu_read_lockXin Long
When sctp dumps all the ep->assocs, it needs to lock_sock first, but now it locks sock in rcu_read_lock, and lock_sock may sleep, which would break rcu_read_lock. This patch is to get and hold one sock when traversing the list. After that and get out of rcu_read_lock, lock and dump it. Then it will traverse the list again to get the next one until all sctp socks are dumped. For sctp_diag_dump_one, it fixes this issue by holding asoc and moving cb() out of rcu_read_lock in sctp_transport_lookup_process. Fixes: 8f840e47f190 ("sctp: add the sctp_diag.c file") Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-30Merge branch 'sctp-fixes'David S. Miller
Xin Long says: ==================== sctp: a bunch of fixes for prsctp polices This patchset is to fix 2 issues for prsctp polices: 1. patch 1 and 2 fix "netperf-Throughput_Mbps -37.2% regression" issue when overloading the CPU. 2. patch 3 fix "prsctp polices should check both sides' prsctp_capable, instead of only local side". ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-30sctp: change to check peer prsctp_capable when using prsctp policesXin Long
Now before using prsctp polices, sctp uses asoc->prsctp_enable to check if prsctp is enabled. However asoc->prsctp_enable is set only means local host support prsctp, sctp should not abandon packet if peer host doesn't enable prsctp. So this patch is to use asoc->peer.prsctp_capable to check if prsctp is enabled on both side, instead of asoc->prsctp_enable, as asoc's peer.prsctp_capable is set only when local and peer both enable prsctp. Fixes: a6c2f792873a ("sctp: implement prsctp TTL policy") Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-30sctp: remove prsctp_param from sctp_chunkXin Long
Now sctp uses chunk->prsctp_param to save the prsctp param for all the prsctp polices, we didn't need to introduce prsctp_param to sctp_chunk. We can just use chunk->sinfo.sinfo_timetolive for RTX and BUF polices, and reuse msg->expires_at for TTL policy, as the prsctp polices and old expires policy are mutual exclusive. This patch is to remove prsctp_param from sctp_chunk, and reuse msg's expires_at for TTL and chunk's sinfo.sinfo_timetolive for RTX and BUF polices. Note that sctp can't use chunk's sinfo.sinfo_timetolive for TTL policy, as it needs a u64 variables to save the expires_at time. This one also fixes the "netperf-Throughput_Mbps -37.2% regression" issue. Fixes: a6c2f792873a ("sctp: implement prsctp TTL policy") Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-30sctp: move sent_count to the memory hole in sctp_chunkXin Long
Now pahole sctp_chunk, it has 2 memory holes: struct sctp_chunk { struct list_head list; atomic_t refcnt; /* XXX 4 bytes hole, try to pack */ ... long unsigned int prsctp_param; int sent_count; /* XXX 4 bytes hole, try to pack */ This patch is to move up sent_count to fill the 1st one and eliminate the 2nd one. It's not just another struct compaction, it also fixes the "netperf- Throughput_Mbps -37.2% regression" issue when overloading the CPU. Fixes: a6c2f792873a ("sctp: implement prsctp TTL policy") Signed-off-by: Xin Long <lucien.xin@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-30mlx4: remove unused fieldsDavid Decotigny
This also can address following UBSAN warnings: [ 36.640343] ================================================================================ [ 36.648772] UBSAN: Undefined behaviour in drivers/net/ethernet/mellanox/mlx4/fw.c:857:26 [ 36.656853] shift exponent 64 is too large for 32-bit type 'int' [ 36.663348] ================================================================================ [ 36.671783] ================================================================================ [ 36.680213] UBSAN: Undefined behaviour in drivers/net/ethernet/mellanox/mlx4/fw.c:861:27 [ 36.688297] shift exponent 35 is too large for 32-bit type 'int' [ 36.694702] ================================================================================ Tested: reboot with UBSAN, no warning. Signed-off-by: David Decotigny <decot@googlers.com> Acked-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Tariq Toukan <tariqt@mellanox.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-30ipv6 addrconf: implement RFC7559 router solicitation backoffMaciej Żenczykowski
This implements: https://tools.ietf.org/html/rfc7559 Backoff is performed according to RFC3315 section 14: https://tools.ietf.org/html/rfc3315#section-14 We allow setting /proc/sys/net/ipv6/conf/*/router_solicitations to a negative value meaning an unlimited number of retransmits, and we make this the new default (inline with the RFC). We also add a new setting: /proc/sys/net/ipv6/conf/*/router_solicitation_max_interval defaulting to 1 hour (per RFC recommendation). Signed-off-by: Maciej Żenczykowski <maze@google.com> Acked-by: Erik Kline <ek@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-30Merge branch 'net_proc_perf'David S. Miller
Jia He says: ==================== Reduce cache miss for snmp_fold_field In a PowerPc server with large cpu number(160), besides commit a3a773726c9f ("net: Optimize snmp stat aggregation by walking all the percpu data at once"), I watched several other snmp_fold_field callsites which would cause high cache miss rate. test source code: ================ My simple test case, which read from the procfs items endlessly: /***********************************************************/ int main(int argc, char **argv) { int i; int fd = -1 ; int rdsize = 0; char buf[LINELEN+1]; buf[LINELEN] = 0; memset(buf,0,LINELEN); if(1 >= argc) { printf("file name empty\n"); return -1; } fd = open(argv[1], O_RDWR, 0644); if(0 > fd){ printf("open error\n"); return -2; } for(i=0;i<0xffffffff;i++) { while(0 < (rdsize = read(fd,buf,LINELEN))){ //nothing here } lseek(fd, 0, SEEK_SET); } close(fd); return 0; } /**********************************************************/ compile and run: ================ gcc test.c -o test perf stat -d -e cache-misses ./test /proc/net/snmp perf stat -d -e cache-misses ./test /proc/net/snmp6 perf stat -d -e cache-misses ./test /proc/net/sctp/snmp perf stat -d -e cache-misses ./test /proc/net/xfrm_stat before the patch set: ==================== Performance counter stats for 'system wide': 355911097 cache-misses [40.08%] 2356829300 L1-dcache-loads [60.04%] 355642645 L1-dcache-load-misses # 15.09% of all L1-dcache hits [60.02%] 346544541 LLC-loads [59.97%] 389763 LLC-load-misses # 0.11% of all LL-cache hits [40.02%] 6.245162638 seconds time elapsed After the patch set: =================== Performance counter stats for 'system wide': 194992476 cache-misses [40.03%] 6718051877 L1-dcache-loads [60.07%] 194871921 L1-dcache-load-misses # 2.90% of all L1-dcache hits [60.11%] 187632232 LLC-loads [60.04%] 464466 LLC-load-misses # 0.25% of all LL-cache hits [39.89%] 6.868422769 seconds time elapsed The cache-miss rate can be reduced from 15% to 2.9% changelog ========= v6: - correct v5 v5: - order local variables from longest to shortest line v4: - move memset into one block of if statement in snmp6_seq_show_item - remove the changes in netstat_seq_show considerred the stack usage is too large v3: - introduce generic interface (suggested by Marcelo Ricardo Leitner) - use max_t instead of self defined macro (suggested by David Miller) v2: - fix bug in udplite statistics. - snmp_seq_show is split into 2 parts ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-30net: Suppress the "Comparison to NULL could be written" warningsJia He
This is to suppress the checkpatch.pl warning "Comparison to NULL could be written". No functional changes here. Signed-off-by: Jia He <hejianet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-30ipv6: Remove useless parameter in __snmp6_fill_statsdevJia He
The parameter items(is always ICMP6_MIB_MAX) is useless for __snmp6_fill_statsdev Signed-off-by: Jia He <hejianet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-30proc: Reduce cache miss in xfrm_statistics_seq_showJia He
This is to use the generic interfaces snmp_get_cpu_field{,64}_batch to aggregate the data by going through all the items of each cpu sequentially. Signed-off-by: Jia He <hejianet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-30proc: Reduce cache miss in sctp_snmp_seq_showJia He
This is to use the generic interfaces snmp_get_cpu_field{,64}_batch to aggregate the data by going through all the items of each cpu sequentially. Signed-off-by: Jia He <hejianet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-30proc: Reduce cache miss in snmp6_seq_showJia He
This is to use the generic interfaces snmp_get_cpu_field{,64}_batch to aggregate the data by going through all the items of each cpu sequentially. Signed-off-by: Jia He <hejianet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-30proc: Reduce cache miss in snmp_seq_showJia He
This is to use the generic interfaces snmp_get_cpu_field{,64}_batch to aggregate the data by going through all the items of each cpu sequentially. Then snmp_seq_show is split into 2 parts to avoid build warning "the frame size" larger than 1024. Signed-off-by: Jia He <hejianet@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-30net:snmp: Introduce generic interfaces for snmp_get_cpu_field{, 64}Jia He
This is to introduce the generic interfaces for snmp_get_cpu_field{,64}. It exchanges the two for-loops for collecting the percpu statistics data. This can aggregate the data by going through all the items of each cpu sequentially. Signed-off-by: Jia He <hejianet@gmail.com> Suggested-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-30Merge tag 'rxrpc-rewrite-20160929' of ↵David S. Miller
git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs David Howells says: ==================== rxrpc: Fixes and adjustments This set of patches contains some fixes and adjustments: (1) Connections for exclusive calls are being reused because the check to work out whether to set RXRPC_CONN_DONT_REUSE is checking where the parameters will be copied to (but haven't yet). (2) Make Tx loss-injection go through the normal return, so the state gets set correctly for what the code thinks it has done. Note lost Tx packets in the tx_data trace rather than the skb tracepoint. (3) Activate channels according to the current state from within the channel_lock to avoid someone changing it on us. (4) Reduce the local endpoint's services list to a single pointer as we don't allow service AF_RXRPC sockets to share UDP ports with other AF_RXRPC sockets, so there can't be more than one element in the list. (5) Request more ACKs in slow-start mode to help monitor the state driving the window configuration. (6) Display the serial number of the packet being ACK'd rather than the ACK packet's own serial number in the congestion trace as this can be related to other entries in the trace. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-30Revert "serial: pl011: add console matching function"Greg Kroah-Hartman
This reverts commit 8b8f347d3a4859d22567f3b8e5bb4a69b1089739 as it causes build errors in linux-next Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Aleksey Makarov <aleksey.makarov@linaro.org> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Russell King <rmk+kernel@armlinux.org.uk> Cc: Christopher Covington <cov@codeaurora.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-09-30Merge tag 'wireless-drivers-next-for-davem-2016-09-29' of ↵David S. Miller
git://git.kernel.org/pub/scm/linux/kernel/git/kvalo/wireless-drivers-next Kalle Valo says: wireless-drivers-next patches for 4.9 Major changes: iwlwifi * work for new hardware support continues * dynamic queue allocation stabilization * improvements in the MSIx code * multiqueue support work continues * new firmware version support (API 26) * add 8275 series support * add 9560 series support * add support for MU-MIMO sniffer * add support for RRM by scan * add support for "reverse" rx packet injection faking hw descriptors * migrate to devm memory allocation handling * Remove support for older firmwares (API older than -17 and -22) wl12xx * support booting the same rootfs with both wl12xx and wl18xx hostap * mark the driver as obsolete ath9k * disable RNG by default ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-30tg3: Avoid NULL pointer dereference in tg3_io_error_detected()Milton Miller
While the driver is probing the adapter, an error may occur before the netdev structure is allocated and attached to pci_dev. In this case, not only netdev isn't available, but the tg3 private structure is also not available as it is just math from the NULL pointer, so dereferences must be skipped. The following trace is seen when the error is triggered: [1.402247] Unable to handle kernel paging request for data at address 0x00001a99 [1.402410] Faulting instruction address: 0xc0000000007e33f8 [1.402450] Oops: Kernel access of bad area, sig: 11 [#1] [1.402481] SMP NR_CPUS=2048 NUMA PowerNV [1.402513] Modules linked in: [1.402545] CPU: 0 PID: 651 Comm: eehd Not tainted 4.4.0-36-generic #55-Ubuntu [1.402591] task: c000001fe4e42a20 ti: c000001fe4e88000 task.ti: c000001fe4e88000 [1.402742] NIP: c0000000007e33f8 LR: c0000000007e3164 CTR: c000000000595ea0 [1.402787] REGS: c000001fe4e8b790 TRAP: 0300 Not tainted (4.4.0-36-generic) [1.402832] MSR: 9000000100009033 <SF,HV,EE,ME,IR,DR,RI,LE> CR: 28000422 XER: 20000000 [1.403058] CFAR: c000000000008468 DAR: 0000000000001a99 DSISR: 42000000 SOFTE: 1 GPR00: c0000000007e3164 c000001fe4e8ba10 c0000000015c5e00 0000000000000000 GPR04: 0000000000000001 0000000000000000 0000000000000039 0000000000000299 GPR08: 0000000000000000 0000000000000001 c000001fe4e88000 0000000000000006 GPR12: 0000000000000000 c00000000fb40000 c0000000000e6558 c000003ca1bffd00 GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 GPR20: 0000000000000000 0000000000000000 0000000000000000 c000000000d52768 GPR24: c000000000d52740 0000000000000100 c000003ca1b52000 0000000000000002 GPR28: 0000000000000900 0000000000000000 c00000000152a0c0 c000003ca1b52000 [1.404226] NIP [c0000000007e33f8] tg3_io_error_detected+0x308/0x340 [1.404265] LR [c0000000007e3164] tg3_io_error_detected+0x74/0x340 This patch avoids the NULL pointer dereference by moving the access after the netdev NULL pointer check on tg3_io_error_detected(). Also, we add a check for netdev being NULL on tg3_io_resume() [suggested by Michael Chan]. Fixes: 0486a063b1ff ("tg3: prevent ifup/ifdown during PCI error recovery") Fixes: dfc8f370316b ("net/tg3: Release IRQs on permanent error") Tested-by: Guilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com> Signed-off-by: Milton Miller <miltonm@us.ibm.com> Signed-off-by: Guilherme G. Piccoli <gpiccoli@linux.vnet.ibm.com> Acked-by: Michael Chan <michael.chan@broadcom.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-30Merge branch 'dsa-global-cosmetics'David S. Miller
Vivien Didelot says: ==================== net: dsa: mv88e6xxx: Global (1) cosmetics The Global (1) internal SMI device of Marvell switches is a set of registers providing support to different units for MAC addresses (ATU), VLANs (VTU), PHY polling (PPU), etc. Chips (like 88E6060) may use a different address for it, or have subtleties in the units (e.g. different number of databases, changing how registers must be accessed), making it hard to maintain properly. This patchset is a first step to polish the Global (1) support, with no functional changes though. Here's basically what it does: - add helpers to access Global1 registers (same for Global2) - remove a few family checks (VTU/STU FID registers) - s/mv88e6xxx_vtu_stu_entry/mv88e6xxx_vtu_entry/ - add a per-chip mv88e6xxx_ops structure of function pointers: struct mv88e6xxx_ops { int (*get_eeprom)(struct mv88e6xxx_chip *chip, struct ethtool_eeprom *eeprom, u8 *data); int (*set_eeprom)(struct mv88e6xxx_chip *chip, struct ethtool_eeprom *eeprom, u8 *data); int (*set_switch_mac)(struct mv88e6xxx_chip *chip, u8 *addr); int (*phy_read)(struct mv88e6xxx_chip *chip, int addr, int reg, u16 *val); int (*phy_write)(struct mv88e6xxx_chip *chip, int addr, int reg, u16 val); }; Future patchsets will add ATU/VTU ops, software reset, etc. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-30net: dsa: mv88e6xxx: add eeprom opsVivien Didelot
Remove EEPROM flags in favor of new {get,set}_eeprom chip-wide functions in the mv88e6xxx_ops structure. Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-30net: dsa: mv88e6xxx: add set_switch_mac to opsVivien Didelot
Add a set_switch_mac chip-wide function to mv88e6xxx_ops and remove MV88E6XXX_FLAG_G2_SWITCH_MAC flags. Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-30net: dsa: mv88e6xxx: add chip-wide opsVivien Didelot
Introduce a mv88e6xxx_ops structure to describe supported chip-wide functions and assign the correct variant to the chip models. For the moment, add only PHY access routines. This allows to get rid of the PHY ops structures and the usage of PHY flags. Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-30net: dsa: mv88e6xxx: rename mv88e6xxx_opsVivien Didelot
The mv88e6xxx_ops is used to describe how to access the chip registers. It can be through SMI (via an MDIO bus), or via another interface such as crafted remote management frames. The correct BUS operations structure is chosen at runtime, depending on the chip address and connectivity. We will need the mv88e6xxx_ops name for future chip-wide operation structure, thus rename mv88e6xxx_ops to more explicit mv88e6xxx_bus_ops. Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-30net: dsa: mv88e6xxx: rename mv88e6xxx_vtu_stu_entryVivien Didelot
The STU (if the switch has one) is abstracted and accessed through the VTU operations and data registers. Thus rename the mv88e6xxx_vtu_stu_entry struct to mv88e6xxx_vtu_entry. Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-30net: dsa: mv88e6xxx: add mv88e6xxx_num_ports helperVivien Didelot
Add an mv88e6xxx_num_ports helper instead of digging in the chip info structure. Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-30net: dsa: mv88e6xxx: expose mv88e6xxx_num_databasesVivien Didelot
The mv88e6xxx_num_databases will be used by shared code, so move it inline to the header file. Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2016-09-30net: dsa: mv88e6xxx: add flags for FID registersVivien Didelot
Add flags to describe the presence of Global 1 ATU FID register (0x01) and VTU FID register (0x02), instead of checking families. Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com> Signed-off-by: David S. Miller <davem@davemloft.net>