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* [IPV4]: Convert IPv4 devconf to an arrayHerbert Xu2007-06-071-7/+7
| | | | | | | | | This patch converts the ipv4_devconf config members (everything except sysctl) to an array. This allows easier manipulation which will be needed later on to provide better management of default config values. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
* [XFRM]: Allow packet drops during larval state resolution.David S. Miller2007-05-241-1/+70
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The current IPSEC rule resolution behavior we have does not work for a lot of people, even though technically it's an improvement from the -EAGAIN buisness we had before. Right now we'll block until the key manager resolves the route. That works for simple cases, but many folks would rather packets get silently dropped until the key manager resolves the IPSEC rules. We can't tell these folks to "set the socket non-blocking" because they don't have control over the non-block setting of things like the sockets used to resolve DNS deep inside of the resolver libraries in libc. With that in mind I coded up the patch below with some help from Herbert Xu which provides packet-drop behavior during larval state resolution, controllable via sysctl and off by default. This lays the framework to either: 1) Make this default at some point or... 2) Move this logic into xfrm{4,6}_policy.c and implement the ARP-like resolution queue we've all been dreaming of. The idea would be to queue packets to the policy, then once the larval state is resolved by the key manager we re-resolve the route and push the packets out. The packets would timeout if the rule didn't get resolved in a certain amount of time. Signed-off-by: David S. Miller <davem@davemloft.net>
* [IPV4]: Remove IPVS icmp hack from route.c for now.David S. Miller2007-05-181-2/+2
| | | | | | | | | Revert: 2d771cd86d4c3af26f34a7bcdc1b87696824cad9 This is dangerous if enabled and a better solution to the problem is being worked on. Signed-off-by: David S. Miller <davem@davemloft.net>
* [IPV4] LVS: Allow to send ICMP unreachable responses when real-servers are ↵Janusz Krzysztofik2007-04-251-2/+2
| | | | | | | | | | | | | | | | | removed this is a small patch by Janusz Krzysztofik to ip_route_output_slow() that allows VIP-less LVS linux director to generate packets originating >From VIP if sysctl_ip_nonlocal_bind is set. In a nutshell, the intention is for an LVS linux director to be able to send ICMP unreachable responses to end-users when real-servers are removed. http://archive.linuxvirtualserver.org/html/lvs-users/2007-01/msg00106.html Signed-off-by: Simon Horman <horms@verge.net.au> Signed-off-by: David S. Miller <davem@davemloft.net>
* [IPv4]: Use rtnl registration interfaceThomas Graf2007-04-251-2/+4
| | | | | Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
* [SK_BUFF]: Introduce ip_hdr(), remove skb->nh.iphArnaldo Carvalho de Melo2007-04-251-3/+3
| | | | | Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [NET]: make seq_operations constStephen Hemminger2007-04-251-2/+2
| | | | | | | | The seq_file operations stuff can be marked constant to get it out of dirty cache. Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* [SK_BUFF]: Introduce skb_reset_network_header(skb)Arnaldo Carvalho de Melo2007-04-251-1/+1
| | | | | | | | | | | | For the common, open coded 'skb->nh.raw = skb->data' operation, so that we can later turn skb->nh.raw into a offset, reducing the size of struct sk_buff in 64bit land while possibly keeping it as a pointer on 32bit. This one touches just the most simple case, next will handle the slightly more "complex" cases. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [SK_BUFF]: Introduce skb_mac_header()Arnaldo Carvalho de Melo2007-04-251-2/+2
| | | | | | | | | | | | For the places where we need a pointer to the mac header, it is still legal to touch skb->mac.raw directly if just adding to, subtracting from or setting it to another layer header. This one also converts some more cases to skb_reset_mac_header() that my regex missed as it had no spaces before nor after '=', ugh. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [SK_BUFF]: Introduce skb_reset_mac_header(skb)Arnaldo Carvalho de Melo2007-04-251-1/+2
| | | | | | | | | | | | For the common, open coded 'skb->mac.raw = skb->data' operation, so that we can later turn skb->mac.raw into a offset, reducing the size of struct sk_buff in 64bit land while possibly keeping it as a pointer on 32bit. This one touches just the most simple case, next will handle the slightly more "complex" cases. Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [NET]: Convert xtime.tv_sec to get_seconds()James Morris2007-04-251-1/+1
| | | | | | | | Where appropriate, convert references to xtime.tv_sec to the get_seconds() helper function. Signed-off-by: James Morris <jmorris@namei.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* [PATCH] remove many unneeded #includes of sched.hTim Schmielau2007-02-141-1/+0
| | | | | | | | | | | | | | | | | | | | | | | | After Al Viro (finally) succeeded in removing the sched.h #include in module.h recently, it makes sense again to remove other superfluous sched.h includes. There are quite a lot of files which include it but don't actually need anything defined in there. Presumably these includes were once needed for macros that used to live in sched.h, but moved to other header files in the course of cleaning it up. To ease the pain, this time I did not fiddle with any header files and only removed #includes from .c-files, which tend to cause less trouble. Compile tested against 2.6.20-rc2 and 2.6.20-rc2-mm2 (with offsets) on alpha, arm, i386, ia64, mips, powerpc, and x86_64 with allnoconfig, defconfig, allmodconfig, and allyesconfig as well as a few randconfigs on x86_64 and all configs in arch/arm/configs on arm. I also checked that no new warnings were introduced by the patch (actually, some warnings are removed that were emitted by unnecessarily included header files). Signed-off-by: Tim Schmielau <tim@physik3.uni-rostock.de> Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [PATCH] mark struct file_operations const 7Arjan van de Ven2007-02-121-2/+2
| | | | | | | | | | | Many struct file_operations in the kernel can be "const". Marking them const moves these to the .rodata section, which avoids false sharing with potential dirty data. In addition it'll catch accidental writes at compile time to these shared resources. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* [IPV4]: Convert ipv4 route to use the new dst_entry 'next' pointerEric Dumazet2007-02-101-28/+28
| | | | | | | | | | | This patch removes the rt_next pointer from 'struct rtable.u' union, and renames u.rt_next to u.dst_rt_next. It also moves 'struct flowi' right after 'struct dst_entry' to prepare the gain on lookups. Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [NET] IPV4: Fix whitespace errors.YOSHIFUJI Hideaki2007-02-101-55/+55
| | | | | Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* [NETLINK]: Don't BUG on undersized allocationsPatrick McHardy2007-02-081-2/+3
| | | | | | | | | | | | | | | Currently netlink users BUG when the allocated skb for an event notification is undersized. While this is certainly a kernel bug, its not critical and crashing the kernel is too drastic, especially when considering that these errors have appeared multiple times in the past and it BUGs even if no listeners are present. This patch replaces BUG by WARN_ON and changes the notification functions to inform potential listeners of undersized allocations using a unique error code (EMSGSIZE). Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
* [IPV4]: Fix BUG of ip_rt_send_redirect()Li Yewang2006-12-181-1/+2
| | | | | | | Fix the redirect packet of the router if the jiffies wraparound. Signed-off-by: Li Yewang <lyw@nanjing-fnst.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [PATCH] sysctl: remove unused "context" paramAlexey Dobriyan2006-12-101-2/+1
| | | | | | | | | | | Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: Andi Kleen <ak@suse.de> Cc: "David S. Miller" <davem@davemloft.net> Cc: David Howells <dhowells@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [XFRM]: Use output device disable_xfrm for forwarded packetsPatrick McHardy2006-12-061-1/+1
| | | | | | | | | | | | | | | Currently the behaviour of disable_xfrm is inconsistent between locally generated and forwarded packets. For locally generated packets disable_xfrm disables the policy lookup if it is set on the output device, for forwarded traffic however it looks at the input device. This makes it impossible to disable xfrm on all devices but a dummy device and use normal routing to direct traffic to that device. Always use the output device when checking disable_xfrm. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
* [RTNETLINK]: Add rtnl_put_cacheinfo() to unify some codeThomas Graf2006-12-021-15/+11
| | | | | | | | IPv4, IPv6, and DECNet all use struct rta_cacheinfo in a similiar way, therefore rtnl_put_cacheinfo() is added to reuse code. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
* [IPV6]: Assorted trivial endianness annotations.Al Viro2006-12-021-2/+2
| | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
* [NET]: Rethink mark field in struct flowiThomas Graf2006-12-021-27/+9
| | | | | | | | | | | | | | | | | | Now that all protocols have been made aware of the mark field it can be moved out of the union thus simplyfing its usage. The config options in the IPv4/IPv6/DECnet subsystems to enable respectively disable mark based routing only obfuscate the code with ifdefs, the cost for the additional comparison in the flow key is insignificant, and most distributions have all these options enabled by default anyway. Therefore it makes sense to remove the config options and enable mark based routing by default. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
* [NET]: Turn nfmark into generic markThomas Graf2006-12-021-5/+5
| | | | | | | | | | nfmark is being used in various subsystems and has become the defacto mark field for all kinds of packets. Therefore it makes sense to rename it to `mark' and remove the dependency on CONFIG_NETFILTER. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
* [NET]: Do not memcmp() over pad bytes of struct flowi.David S. Miller2006-10-121-3/+9
| | | | | | | | | | They are not necessarily initialized to zero by the compiler, for example when using run-time initializers of automatic on-stack variables. Noticed by Eric Dumazet and Patrick McHardy. Signed-off-by: David S. Miller <davem@davemloft.net>
* [IPV4]: RTA_{DST,SRC,GATEWAY,PREFSRC} annotatedAl Viro2006-09-281-7/+7
| | | | | | | these are passed net-endian; use be32 netlink accessors Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
* [IPV4] net/ipv4/route.c: trivial endianness annotationsAl Viro2006-09-281-8/+8
| | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
* [IPV4]: fib_validate_source() annotationsAl Viro2006-09-281-1/+2
| | | | | | | annotated arguments and inferred net-endian variables in callers Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
* [IPV4]: inet_select_addr() annotationsAl Viro2006-09-281-2/+2
| | | | | | | | argument and return value are net-endian. Annotated function and inferred net-endian variables in callers. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
* [IPV4]: annotate rt_hash_code() usersAl Viro2006-09-281-17/+17
| | | | | Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
* [IPV4]: ip_rt_redirect() annotationsAl Viro2006-09-281-3/+3
| | | | | | | The first 4 arguments of ip_rt_redirect() are net-endian. Annotated. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
* [IPV4]: ip_route_input() annotationsAl Viro2006-09-281-10/+12
| | | | | | | | | | | | ip_route_input() takes net-endian source and destination address. * Annotated as such. * arguments of its invocations annotated where needed. * local helpers getting the same values passed to by it (ip_route_input_mc(), ip_route_input_slow(), ip_handle_martian_source(), ip_mkroute_input(), ip_mkroute_input_def(), __mkroute_input()) annotated Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
* [NET]: Use SLAB_PANICAlexey Dobriyan2006-09-221-7/+3
| | | | | Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [IPv4]: Convert route get to new netlink apiThomas Graf2006-09-221-39/+45
| | | | | | | | Fixes various unvalidated netlink attributes causing memory corruptions when left empty by userspace applications. Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
* [IPv4]: Convert FIB dumping to use new netlink apiThomas Graf2006-09-221-35/+33
| | | | | Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
* [RTNETLINK]: Use rtnl_unicast() for rtnetlink unicastsThomas Graf2006-09-221-4/+3
| | | | | Signed-off-by: Thomas Graf <tgraf@suug.ch> Signed-off-by: David S. Miller <davem@davemloft.net>
* [NET]: Introduce RTA_TABLE/FRA_TABLE attributesPatrick McHardy2006-09-221-0/+1
| | | | | | | | | | | | Introduce RTA_TABLE route attribute and FRA_TABLE routing rule attribute to hold 32 bit routing table IDs. Usespace compatibility is provided by continuing to accept and send the rtm_table field, but because of its limited size it can only carry the low 8 bits of the table ID. This implies that if larger IDs are used, _all_ userspace programs using them need to use RTA_TABLE. Signed-off-by: Patrick McHardy <kaber@trash.net> Signed-off-by: David S. Miller <davem@davemloft.net>
* [IPV4]: Limit rt cache size properly.Kirill Korotaev2006-08-071-1/+1
| | | | | | | | | | | | | | | | | | | From: Kirill Korotaev <dev@sw.ru> During OpenVZ stress testing we found that UDP traffic with random src can generate too much excessive rt hash growing leading finally to OOM and kernel panics. It was found that for 4GB i686 system (having 1048576 total pages and 225280 normal zone pages) kernel allocates the following route hash: syslog: IP route cache hash table entries: 262144 (order: 8, 1048576 bytes) => ip_rt_max_size = 4194304 entries, i.e. max rt size is 4194304 * 256b = 1Gb of RAM > normal_zone Attached the patch which removes HASH_HIGHMEM flag from alloc_large_system_hash() call. Signed-off-by: David S. Miller <davem@davemloft.net>
* [NET]: Core net changes to generate neteventsTom Tucker2006-08-021-0/+8
| | | | | | | | | | | Generate netevents for: - neighbour changes - routing redirects - pmtu changes Signed-off-by: Tom Tucker <tom@opengridcomputing.com> Signed-off-by: Steve Wise <swise@opengridcomputing.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [PATCH] lockdep: fix RT_HASH_LOCK_SZIngo Molnar2006-07-031-9/+14
| | | | | | | | | | On lockdep we have a quite big spinlock_t, so keep the size down. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [PATCH] lockdep: prove spinlock rwlock locking correctnessIngo Molnar2006-07-031-1/+2
| | | | | | | | | | Use the lock validator framework to prove spinlock and rwlock locking correctness. Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* Remove obsolete #include <linux/config.h>Jörn Engel2006-06-301-1/+0
| | | | | Signed-off-by: Jörn Engel <joern@wohnheim.fh-wedel.de> Signed-off-by: Adrian Bunk <bunk@stusta.de>
* [PATCH] Define __raw_get_cpu_var and use itPaul Mackerras2006-06-251-1/+1
| | | | | | | | | | | | | | | | | | | | | | | There are several instances of per_cpu(foo, raw_smp_processor_id()), which is semantically equivalent to __get_cpu_var(foo) but without the warning that smp_processor_id() can give if CONFIG_DEBUG_PREEMPT is enabled. For those architectures with optimized per-cpu implementations, namely ia64, powerpc, s390, sparc64 and x86_64, per_cpu() turns into more and slower code than __get_cpu_var(), so it would be preferable to use __get_cpu_var on those platforms. This defines a __raw_get_cpu_var(x) macro which turns into per_cpu(x, raw_smp_processor_id()) on architectures that use the generic per-cpu implementation, and turns into __get_cpu_var(x) on the architectures that have an optimized per-cpu implementation. Signed-off-by: Paul Mackerras <paulus@samba.org> Acked-by: David S. Miller <davem@davemloft.net> Acked-by: Ingo Molnar <mingo@elte.hu> Acked-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [IPV4]: ip_route_input panic fixStephen Hemminger2006-04-171-1/+4
| | | | | | | | | | | This fixes http://bugzilla.kernel.org/show_bug.cgi?id=6388 The bug is caused by ip_route_input dereferencing skb->nh.protocol of the dummy skb passed dow from inet_rtm_getroute (Thanks Thomas for seeing it). It only happens if the route requested is for a multicast IP address. Signed-off-by: Stephen Hemminger <shemminger@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* [PATCH] for_each_possible_cpu: network codesKAMEZAWA Hiroyuki2006-04-111-1/+1
| | | | | | | | | | | | | | | | | for_each_cpu() actually iterates across all possible CPUs. We've had mistakes in the past where people were using for_each_cpu() where they should have been iterating across only online or present CPUs. This is inefficient and possibly buggy. We're renaming for_each_cpu() to for_each_possible_cpu() to avoid this in the future. This patch replaces for_each_cpu with for_each_possible_cpu under /net Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Acked-by: "David S. Miller" <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
* [IPV4]: Aggregate route entries with different TOS valuesIlia Sotnikov2006-03-251-27/+18
| | | | | | | | | | | | | | | | | | | | | | | When we get an ICMP need-to-frag message, the original TOS value in the ICMP payload cannot be used as a key to look up the routes to update. This is because the TOS field may have been modified by routers on the way. Similarly, ip_rt_redirect should also ignore the TOS as the router that gave us the message may have modified the TOS value. The patch achieves this objective by aggregating entries with different TOS values (but are otherwise identical) into the same bucket. This makes it easy to update them at the same time when an ICMP message is received. In future we should use a twin-hashing scheme where teh aggregation occurs at the entry level. That is, the TOS goes back into the hash for normal lookups while ICMP lookups will end up with a node that gives us a list that contains all other route entries that differ only by TOS. Signed-off-by: Ilia Sotnikov <hostcc@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
* [IPV4]: Fix garbage collection of multipath route entriesSuresh Bhogavilli2006-02-231-1/+1
| | | | | | | | | | When garbage collecting route cache entries of multipath routes in rt_garbage_collect(), entries were deleted from the hash bucket 'i' while holding a spin lock on bucket 'k' resulting in a system hang. Delete entries, if any, from bucket 'k' instead. Signed-off-by: Suresh Bhogavilli <sbhogavilli@verisign.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [IPV4]: RT_CACHE_STAT_INC() warning fixAndrew Morton2006-01-171-1/+2
| | | | | | | | | BUG: using smp_processor_id() in preemptible [00000001] code: rpc.statd/2408 And it _is_ a bug, but I guess we don't care enough to add preempt_disable(). Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* [IPV4]: rt_cache_stat can be statically definedEric Dumazet2006-01-171-10/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Using __get_cpu_var(obj) is slightly faster than per_cpu_ptr(obj, raw_smp_processor_id()). 1) Smaller code and memory use For static and small objects, DEFINE_PER_CPU(type, object) is preferred over a alloc_percpu() : Better and smaller code to access them, and no extra memory (storing the pointer, and the percpu array of pointers) x86_64 code before patch mov 1237577(%rip),%rax # ffffffff803e5990 <rt_cache_stat> not %rax # part of per_cpu machinery mov %gs:0x3c,%edx # get cpu number movslq %edx,%rdx # extend 32 bits cpu number to 64 bits mov (%rax,%rdx,8),%rax # get the pointer for this cpu incl 0x38(%rax) x86_64 code after patch mov $per_cpu__rt_cache_stat,%rdx mov %gs:0x48,%rax # get percpu data offset incl 0x38(%rax,%rdx,1) 2) False sharing avoidance for SMP : For a small NR_CPUS, the array of per cpu pointers allocated in alloc_percpu() can be <= 32 bytes. This let slab code gives a part of a cache line. If the other part of this 64 bytes (or 128 bytes) cache line is used by a mostly written object, we can have false sharing and expensive per_cpu_ptr() operations. Size of rt_cache_stat is 64 bytes, so this patch is not a danger of a too big increase of bss (in UP mode) or static per_cpu data for SMP (PERCPU_ENOUGH_ROOM is currently 32768 bytes) Signed-off-by: Eric Dumazet <dada1@cosmosbay.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* [NET]: Add const markers to various variables.Arjan van de Ven2005-11-291-1/+1
| | | | | | | | | | | the patch below marks various variables const in net/; the goal is to move them to the .rodata section so that they can't false-share cachelines with things that get written to, as well as potentially helping gcc a bit with optimisations. (these were found using a gcc patch to warn about such variables) Signed-off-by: Arjan van de Ven <arjan@infradead.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* [IPV4] tcp/route: Another look at hash table sizesMike Stroyan2005-11-291-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The tcp_ehash hash table gets too big on systems with really big memory. It is worse on systems with pages larger than 4KB. It wastes memory that could be better used. It also makes the netstat command slow because reading /proc/net/tcp and /proc/net/tcp6 needs to go through the full hash table. The default value should not be larger for larger page sizes. It seems that the effect of page size is an unintended error dating back a long time. I also wonder if the default value really should be a larger fraction of memory for systems with more memory. While systems with really big ram can afford more space for hash tables, it is not clear to me that they benefit from increasing the allocation ratio for this table. The amount of memory allocated is determined by net/ipv4/tcp.c:tcp_init and mm/page_alloc.c:alloc_large_system_hash. tcp_init calls alloc_large_system_hash passing parameters- bucketsize=sizeof(struct tcp_ehash_bucket) numentries=thash_entries scale=(num_physpages >= 128 * 1024) ? (25-PAGE_SHIFT) : (27-PAGE_SHIFT) limit=0 On i386, PAGE_SHIFT is 12 for a page size of 4K On ia64, PAGE_SHIFT defaults to 14 for a page size of 16K The num_physpages test above makes the allocation take a larger fraction of the total memory on systems with larger memory. The threshold size for a i386 system is 512MB. For an ia64 system with 16KB pages the threshold is 2GB. For smaller memory systems- On i386, scale = (27 - 12) = 15 On ia64, scale = (27 - 14) = 13 For larger memory systems- On i386, scale = (25 - 12) = 13 On ia64, scale = (25 - 14) = 11 For the rest of this discussion, I'll just track the larger memory case. The default behavior has numentries=thash_entries=0, so the allocated size is determined by either scale or by the default limit of 1/16 of total memory. In alloc_large_system_hash- | numentries = (flags & HASH_HIGHMEM) ? nr_all_pages : nr_kernel_pages; | numentries += (1UL << (20 - PAGE_SHIFT)) - 1; | numentries >>= 20 - PAGE_SHIFT; | numentries <<= 20 - PAGE_SHIFT; At this point, numentries is pages for all of memory, rounded up to the nearest megabyte boundary. | /* limit to 1 bucket per 2^scale bytes of low memory */ | if (scale > PAGE_SHIFT) | numentries >>= (scale - PAGE_SHIFT); | else | numentries <<= (PAGE_SHIFT - scale); On i386, numentries >>= (13 - 12), so numentries is 1/8196 of bytes of total memory. On ia64, numentries <<= (14 - 11), so numentries is 1/2048 of bytes of total memory. | log2qty = long_log2(numentries); | | do { | size = bucketsize << log2qty; bucketsize is 16, so size is 16 times numentries, rounded down to a power of two. On i386, size is 1/512 of bytes of total memory. On ia64, size is 1/128 of bytes of total memory. For smaller systems the results are On i386, size is 1/2048 of bytes of total memory. On ia64, size is 1/512 of bytes of total memory. The large page effect can be removed by just replacing the use of PAGE_SHIFT with a constant of 12 in the calls to alloc_large_system_hash. That makes them more like the other uses of that function from fs/inode.c and fs/dcache.c Signed-off-by: David S. Miller <davem@davemloft.net>
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