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path: root/net/ipv4/fib_trie.c
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2015-03-06fib_trie: Pull empty_children and full_children into tnodeAlexander Duyck
This pulls the information about the child array out of the key_vector and places it in the tnode since that is where it is needed. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-06fib_trie: Move rcu from key_vector to tnode, add accessors.Alexander Duyck
RCU is only needed once for the entire node, not once per key_vector so we can pull that out and move it to the tnode structure. In addition add accessors to be used inside the RCU functions so that we can more easily get from the key vector to either the tnode or the trie pointers. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-06fib_trie: Add tnode struct as a container for fields not needed in key_vectorAlexander Duyck
This change pulls the fields not explicitly needed in the key_vector and placed them in the new tnode structure. By doing this we will eventually be able to reduce the key_vector down to 16 bytes on 64 bit systems, and 12 bytes on 32 bit systems. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-06fib_trie: Rename tnode_child_length to child_lengthAlexander Duyck
We are now checking the length of a key_vector instead of a tnode so it makes sense to probably just rename this to child_length since it would probably even be applicable to a leaf. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-06fib_trie: replace tnode_get_child functions with get_child macrosAlexander Duyck
I am replacing the tnode_get_child call with get_child since we are techically pulling the child out of a key_vector now and not a tnode. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-06fib_trie: Rename tnode to key_vectorAlexander Duyck
Rename the tnode to key_vector. The key_vector will be the eventual container for all of the information needed by either a leaf or a tnode. The final result should be much smaller than the 40 bytes currently needed for either one. This also updates the trie struct so that it contains an array of size 1 of tnode pointers. This is to bring the structure more inline with how an actual tnode itself is configured. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-06fib_trie: Return pointer to tnode pointer in resize/inflate/halveAlexander Duyck
Resize related functions now all return a pointer to the pointer that references the object that was resized. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-06fib_trie: Minor cleanups to fib_table_flush_externalAlexander Duyck
This change just does a couple of minor cleanups on fib_table_flush_external. Specifically it addresses the fact that resize was being called even though nothing was being removed from the table, and it drops an unecessary indent since we could just call continue on the inverse of the fi && flag check. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-06ipv4: Fix unused variable warnings in fib_table_flush_external.David S. Miller
net/ipv4/fib_trie.c: In function ‘fib_table_flush_external’: net/ipv4/fib_trie.c:1572:6: warning: unused variable ‘found’ [-Wunused-variable] int found = 0; ^ net/ipv4/fib_trie.c:1571:16: warning: unused variable ‘slen’ [-Wunused-variable] unsigned char slen; ^ Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-06fib: hook IPv4 fib for hardware offloadScott Feldman
Call into the switchdev driver any time an IPv4 fib entry is added/modified/deleted from the kernel's FIB. The switchdev driver may or may not install the route to the offload device. In the case where the driver tries to install the route and something goes wrong (device's routing table is full, etc), then all of the offloaded routes will be flushed from the device, route forwarding falls back to the kernel, and no more routes are offloading. We can refine this logic later. For now, use the simplist model of offloading routes up to the point of failure, and then on failure, undo everything and mark IPv4 offloading disabled. Signed-off-by: Scott Feldman <sfeldma@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-06switchdev: don't support custom ip rules, for nowScott Feldman
Keep switchdev FIB offload model simple for now and don't allow custom ip rules. Signed-off-by: Scott Feldman <sfeldma@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-04fib_trie: Prevent allocating tnode if bits is too big for size_tAlexander Duyck
This patch adds code to prevent us from attempting to allocate a tnode with a size larger than what can be represented by size_t. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-04fib_trie: Update last spot w/ idx >> n->bits code and explanationAlexander Duyck
This change updates the fib_table_lookup function so that it is in sync with the fib_find_node function in terms of the explanation for the index check based on the bits value. I have also updated it from doing a mask to just doing a compare as I have found that seems to provide more options to the compiler as I have seen it turn this into a shift of the value and test under some circumstances. In addition I addressed one minor issue in which we kept computing the key ^ n->key when checking the fib aliases. I pulled the xor out of the loop in order to reduce the number of memory reads in the lookup. As a result we should save a couple cycles since the xor is only done once much earlier in the lookup. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-04fib_trie: Make fib_table rcu safeAlexander Duyck
The fib_table was wrapped in several places with an rcu_read_lock/rcu_read_unlock however after looking over the code I found several spots where the tables were being accessed as just standard pointers without any protections. This change fixes that so that all of the proper protections are in place when accessing the table to take RCU replacement or removal of the table into account. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-04fib_trie: move leaf and tnode to occupy the same spot in the key vectorAlexander Duyck
If we are going to compact the leaf and tnode we first need to make sure the fields are all in the same place. In that regard I am moving the leaf pointer which represents the fib_alias hash list to occupy what is currently the first key_vector pointer. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-04fib_trie: Update insert and delete to make use of tp from find_nodeAlexander Duyck
This change makes it so that the insert and delete functions make use of the tnode pointer returned in the fib_find_node call. By doing this we will not have to rely on the parent pointer in the leaf which will be going away soon. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-04fib_trie: Fib find node should return parentAlexander Duyck
This change makes it so that the parent pointer is returned by reference in fib_find_node. By doing this I can use it to find the parent node when I am performing an insertion and I don't have to look for it again in fib_insert_node. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-04fib_trie: Fib walk rcu should take a tnode and key instead of a trie and a leafAlexander Duyck
This change makes it so that leaf_walk_rcu takes a tnode and a key instead of the trie and a leaf. The main idea behind this is to avoid using the leaf parent pointer as that can have additional overhead in the future as I am trying to reduce the size of a leaf down to 16 bytes on 64b systems and 12b on 32b systems. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-04fib_trie: Only resize tnodes once instead of on each leaf removal in ↵Alexander Duyck
fib_table_flush This change makes it so that we only call resize on the tnodes, instead of from each of the leaves. By doing this we can significantly reduce the amount of time spent resizing as we can update all of the leaves in the tnode first before we make any determinations about resizing. As a result we can simply free the tnode in the case that all of the leaves from a given tnode are flushed instead of resizing with each leaf removed. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-27fib_trie: Remove leaf_infoAlexander Duyck
At this point the leaf_info hash is redundant. By adding the suffix length to the fib_alias hash list we no longer have need of leaf_info as we can determine the prefix length from fa_slen. So we can compress things by dropping the leaf_info structure from fib_trie and instead directly connect the leaves to the fib_alias hash list. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-27fib_trie: Add slen to fib aliasAlexander Duyck
Make use of an empty spot in the alias to store the suffix length so that we don't need to pull that information from the leaf_info structure. This patch also makes a slight change to the user statistics. Instead of incrementing semantic_match_miss once per leaf_info miss we now just increment it once per leaf if a match was not found. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-27fib_trie: Replace plen with slen in leaf_infoAlexander Duyck
This replaces the prefix length variable in the leaf_info structure with a suffix length value, or host identifier length in bits. By doing this it makes it easier to sort out since the tnodes and leaf are carrying this value as well since it is compatible with the ->pos field in tnodes. I also cleaned up one spot that had some list manipulation that could be simplified. I basically updated it so that we just use hlist_add_head_rcu instead of calling hlist_add_before_rcu on the first node in the list. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-27fib_trie: Convert fib_alias to hlist from listAlexander Duyck
There isn't any advantage to having it as a list and by making it an hlist we make the fib_alias more compatible with the list_info in terms of the type of list used. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-25fib_trie: Various clean-ups for handling slenAlexander Duyck
While doing further work on the fib_trie I noted a few items. First I was using calls that were far more complicated than they needed to be for determining when to push/pull the suffix length. I have updated the code to reflect the simplier logic. The second issue is that I realised we weren't necessarily handling the case of a leaf_info struct surviving a flush. I have updated the logic so that now we will call pull_suffix in the event of having a leaf info value left in the leaf after flushing it. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-25fib_trie: Move fib_find_alias to file where it is usedAlexander Duyck
The function fib_find_alias is only accessed by functions in fib_trie.c as such it makes sense to relocate it and cast it as static so that the compiler can take advantage of optimizations it can do to it as a local function. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-25fib_trie: Use empty_children instead of counting empty nodes in stats collectionAlexander Duyck
It doesn't make much sense to count the pointers ourselves when empty_children already has a count for the number of NULL pointers stored in the tnode. As such save ourselves the cycles and just use empty_children. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-25fib_trie: Add collapse() and should_collapse() to resizeAlexander Duyck
This patch really does two things. First it pulls the logic for determining if we should collapse one node out of the tree and the actual code doing the collapse into a separate pair of functions. This helps to make the changes to these areas more readable. Second it encodes the upper 32b of the empty_children value onto the full_children value in the case of bits == KEYLENGTH. By doing this we are able to handle the case of a 32b node where empty_children would appear to be 0 when it was actually 1ul << 32. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-25fib_trie: Fall back to slen update on inflate/halve failureAlexander Duyck
This change corrects an issue where if inflate or halve fails we were exiting the resize function without at least updating the slen for the node. To correct this I have moved the update of max_size into the while loop so that it is only decremented on a successful call to either inflate or halve. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-25fib_trie: Fix RCU bug and merge similar bits of inflate/halveAlexander Duyck
This patch addresses two issues. The first issue is the fact that I believe I had the RCU freeing sequence slightly out of order. As a result we could get into an issue if a caller went into a child of a child of the new node, then backtraced into the to be freed parent, and then attempted to access a child of a child that may have been consumed in a resize of one of the new nodes children. To resolve this I have moved the resize after we have freed the oldtnode. The only side effect of this is that we will now be calling resize on more nodes in the case of inflate due to the fact that we don't have a good way to test to see if a full_tnode on the new node was there before or after the allocation. This should have minimal impact however since the node should already be correctly size so it is just the cost of calling should_inflate that we will be taking on the node which is only a couple of cycles. The second issue is the fact that inflate and halve were essentially doing the same thing after the new node was added to the trie replacing the old one. As such it wasn't really necessary to keep the code in both functions so I have split it out into two other functions, called replace and update_children. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-25fib_trie: Use index & (~0ul << n->bits) instead of index >> n->bitsAlexander Duyck
In doing performance testing and analysis of the changes I recently found that by shifting the index I had created an unnecessary dependency. I have updated the code so that we instead shift a mask by bits and then just test against that as that should save us about 2 CPU cycles since we can generate the mask while the key and pos are being processed. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-31fib_trie: Add tracking value for suffix lengthAlexander Duyck
This change adds a tracking value for the maximum suffix length of all prefixes stored in any given tnode. With this value we can determine if we need to backtrace or not based on if the suffix is greater than the pos value. By doing this we can reduce the CPU overhead for lookups in the local table as many of the prefixes there are 32b long and have a suffix length of 0 meaning we can immediately backtrace to the root node without needing to test any of the nodes between it and where we ended up. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-31fib_trie: Remove checks for index >= tnode_child_length from tnode_get_childAlexander Duyck
For some reason the compiler doesn't seem to understand that when we are in a loop that runs from tnode_child_length - 1 to 0 we don't expect the value of tn->bits to change. As such every call to tnode_get_child was rerunning tnode_chile_length which ended up consuming quite a bit of space in the resultant assembly code. I have gone though and verified that in all cases where tnode_get_child is used we are either winding though a fixed loop from tnode_child_length - 1 to 0, or are in a fastpath case where we are verifying the value by either checking for any remaining bits after shifting index by bits and testing for leaf, or by using tnode_child_length. size net/ipv4/fib_trie.o Before: text data bss dec hex filename 15506 376 8 15890 3e12 net/ipv4/fib_trie.o After: text data bss dec hex filename 14827 376 8 15211 3b6b net/ipv4/fib_trie.o Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-31fib_trie: inflate/halve nodes in a more RCU friendly wayAlexander Duyck
This change pulls the node_set_parent functionality out of put_child_reorg and instead leaves that to the function to take care of as well. By doing this we can fully construct the new cluster of tnodes and all of the pointers out of it before we start routing pointers into it. I am suspecting this will likely fix some concurency issues though I don't have a good test to show as such. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-31fib_trie: Push tnode flushing down to inflate/halveAlexander Duyck
This change pushes the tnode freeing down into the inflate and halve functions. It makes more sense here as we have a better grasp of what is going on and when a given cluster of nodes is ready to be freed. I believe this may address a bug in the freeing logic as well. For some reason if the freelist got to a certain size we would call synchronize_rcu(). I'm assuming that what they meant to do is call synchronize_rcu() after they had handed off that much memory via call_rcu(). As such that is what I have updated the behavior to be. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-31fib_trie: Push assignment of child to parent down into inflate/halveAlexander Duyck
This change makes it so that the assignment of the tnode to the parent is handled directly within whatever function is currently handling the node be it inflate, halve, or resize. By doing this we can avoid some of the need to set NULL pointers in the tree while we are resizing the subnodes. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-31fib_trie: Add functions should_inflate and should_halveAlexander Duyck
This change pulls the logic for if we should inflate/halve the nodes out into separate functions. It also addresses what I believe is a bug where 1 full node is all that is needed to keep a node from ever being halved. Simple script to reproduce the issue: modprobe dummy; ifconfig dummy0 up for i in `seq 0 255`; do ifconfig dummy0:$i 10.0.${i}.1/24 up; done ifconfig dummy0:256 10.0.255.33/16 up for i in `seq 0 254`; do ifconfig dummy0:$i down; done Results from /proc/net/fib_triestat Before: Local: Aver depth: 3.00 Max depth: 4 Leaves: 17 Prefixes: 18 Internal nodes: 11 1: 8 2: 2 10: 1 Pointers: 1048 Null ptrs: 1021 Total size: 11 kB After: Local: Aver depth: 3.41 Max depth: 5 Leaves: 17 Prefixes: 18 Internal nodes: 12 1: 8 2: 3 3: 1 Pointers: 36 Null ptrs: 8 Total size: 3 kB Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-31fib_trie: Move resize to after inflate/halveAlexander Duyck
This change consists of a cut/paste of resize to behind inflate and halve so that I could remove the two function prototypes. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-31fib_trie: Push rcu_read_lock/unlock to callersAlexander Duyck
This change is to start cleaning up some of the rcu_read_lock/unlock handling. I realized while reviewing the code there are several spots that I don't believe are being handled correctly or are masking warnings by locally calling rcu_read_lock/unlock instead of calling them at the correct level. A common example is a call to fib_get_table followed by fib_table_lookup. The rcu_read_lock/unlock ought to wrap both but there are several spots where they were not wrapped. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-31fib_trie: Use unsigned long for anything dealing with a shift by bitsAlexander Duyck
This change makes it so that anything that can be shifted by, or compared to a value shifted by bits is updated to be an unsigned long. This is mostly a precaution against an insanely huge address space that somehow starts coming close to the 2^32 root node size which would require something like 1.5 billion addresses. I chose unsigned long instead of unsigned long long since I do not believe it is possible to allocate a 32 bit tnode on a 32 bit system as the memory consumed would be 16GB + 28B which exceeds the addressible space for any one process. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-31fib_trie: Update meaning of pos to represent unchecked bitsAlexander Duyck
This change moves the pos value to the other side of the "bits" field. By doing this it actually simplifies a significant amount of code in the trie. For example when halving a tree we know that the bit lost exists at oldnode->pos, and if we inflate the tree the new bit being add is at tn->pos. Previously to find those bits you would have to subtract pos and bits from the keylength or start with a value of (1 << 31) and then shift that. There are a number of spots throughout the code that benefit from this. In the case of the hot-path searches the main advantage is that we can drop 2 or more operations from the search path as we no longer need to compute the value for the index to be shifted by and can instead just use the raw pos value. In addition the tkey_extract_bits is now defunct and can be replaced by get_index since the two operations were doing the same thing, but now get_index does it much more quickly as it is only an xor and shift versus a pair of shifts and a subtraction. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-31fib_trie: Optimize fib_table_insertAlexander Duyck
This patch updates the fib_table_insert function to take advantage of the changes made to improve the performance of fib_table_lookup. As a result the code should be smaller and run faster then the original. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-31fib_trie: Optimize fib_find_nodeAlexander Duyck
This patch makes use of the same features I made use of for fib_table_lookup to streamline fib_find_node. The resultant code should be smaller and run faster than the original. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-31fib_trie: Optimize fib_table_lookup to avoid wasting time on loops/variablesAlexander Duyck
This patch is meant to reduce the complexity of fib_table_lookup by reducing the number of variables to the bare minimum while still keeping the same if not improved functionality versus the original. Most of this change was started off by the desire to rid the function of chopped_off and current_prefix_length as they actually added very little to the function since they only applied when computing the cindex. I was able to replace them mostly with just a check for the prefix match. As long as the prefix between the key and the node being tested was the same we know we can search the tnode fully versus just testing cindex 0. The second portion of the change ended up being a massive reordering. Originally the calls to check_leaf were up near the start of the loop, and the backtracing and descending into lower levels of tnodes was later. This didn't make much sense as the structure of the tree means the leaves are always the last thing to be tested. As such I reordered things so that we instead have a loop that will delve into the tree and only exit when we have either found a leaf or we have exhausted the tree. The advantage of rearranging things like this is that we can fully inline check_leaf since there is now only one reference to it in the function. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-31fib_trie: Merge leaf into tnodeAlexander Duyck
This change makes it so that leaf and tnode are the same struct. As a result there is no need for rt_trie_node anymore since everyting can be merged into tnode. On 32b systems this results in the leaf being 4 bytes larger, however I don't know if that is really an issue as this and an eariler patch that added bits & pos have increased the size from 20 to 28. If I am not mistaken slub/slab allocate on power of 2 sizes so 20 was likely being rounded up to 32 anyway. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-31fib_trie: Merge tnode_free and leaf_free into node_freeAlexander Duyck
Both the leaf and the tnode had an rcu_head in them, but they had them in slightly different places. Since we now have them in the same spot and know that any node with bits == 0 is a leaf and the rest are either vmalloc or kmalloc tnodes depending on the value of bits it makes it easy to combine the functions and reduce overhead. In addition I have taken advantage of the rcu_head pointer to go ahead and put together a simple linked list instead of using the tnode pointer as this way we can merge either type of structure for freeing. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-31fib_trie: Make leaf and tnode more uniformAlexander Duyck
This change makes some fundamental changes to the way leaves and tnodes are constructed. The big differences are: 1. Leaves now populate pos and bits indicating their full key size. 2. Trie nodes now mask out their lower bits to be consistent with the leaf 3. Both structures have been reordered so that rt_trie_node now consisists of a much larger region including the pos, bits, and rcu portions of the tnode structure. On 32b systems this will result in the leaf being 4B larger as the pos and bits values were added to a hole created by the key as it was only 4B in length. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-31fib_trie: Update usage stats to be percpu instead of global variablesAlexander Duyck
The trie usage stats were currently being shared by all threads that were calling fib_table_lookup. As a result when multiple threads were performing lookups simultaneously the trie would begin to cache bounce between those threads. In order to prevent this I have updated the usage stats to use a set of percpu variables. By doing this we should be able to avoid the cache bouncing and still make use of these stats. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-12fib_trie: Fix trie balancing issue if new node pushes down existing nodeAlexander Duyck
This patch addresses an issue with the level compression of the fib_trie. Specifically in the case of adding a new leaf that triggers a new node to be added that takes the place of the old node. The result is a trie where the 1 child tnode is on one side and one leaf is on the other which gives you a very deep trie. Below is the script I used to generate a trie on dummy0 with a 10.X.X.X family of addresses. ip link add type dummy ipval=184549374 bit=2 for i in `seq 1 23` do ifconfig dummy0:$bit $ipval/8 ipval=`expr $ipval - $bit` bit=`expr $bit \* 2` done cat /proc/net/fib_triestat Running the script before the patch: Local: Aver depth: 10.82 Max depth: 23 Leaves: 29 Prefixes: 30 Internal nodes: 27 1: 26 2: 1 Pointers: 56 Null ptrs: 1 Total size: 5 kB After applying the patch and repeating: Local: Aver depth: 4.72 Max depth: 9 Leaves: 29 Prefixes: 30 Internal nodes: 12 1: 3 2: 2 3: 7 Pointers: 70 Null ptrs: 30 Total size: 4 kB What this fix does is start the rebalance at the newly created tnode instead of at the parent tnode. This way if there is a gap between the parent and the new node it doesn't prevent the new tnode from being coalesced with any pre-existing nodes that may have been pushed into one of the new nodes child branches. Signed-off-by: Alexander Duyck <alexander.h.duyck@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2014-08-06list: fix order of arguments for hlist_add_after(_rcu)Ken Helias
All other add functions for lists have the new item as first argument and the position where it is added as second argument. This was changed for no good reason in this function and makes using it unnecessary confusing. The name was changed to hlist_add_behind() to cause unconverted code to generate a compile error instead of using the wrong parameter order. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Ken Helias <kenhelias@firemail.de> Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com> Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com> [intel driver bits] Cc: Hugh Dickins <hughd@google.com> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-11-15seq_file: remove "%n" usage from seq_file usersTetsuo Handa
All seq_printf() users are using "%n" for calculating padding size, convert them to use seq_setwidth() / seq_pad() pair. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: Kees Cook <keescook@chromium.org> Cc: Joe Perches <joe@perches.com> Cc: David Miller <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>