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2010-09-27sunrpc: Tag svc_xprt with netPavel Emelyanov
The transport representation should be per-net of course. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2010-09-27sunrpc: Make xprt auth cache release work with the xprtPavel Emelyanov
This is done in order to facilitate getting the ip_map_cache from which to put the ip_map. Signed-off-by: Pavel Emelyanov <xemul@openvz.org> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2010-09-07svcrpc: minor cache cleanupJ. Bruce Fields
Pull out some code into helper functions, fix a typo. Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2010-09-07sunrpc/cache: allow threads to block while waiting for cache update.NeilBrown
The current practice of waiting for cache updates by queueing the whole request to be retried has (at least) two problems. 1/ With NFSv4, requests can be quite complex and re-trying a whole request when a later part fails should only be a last-resort, not a normal practice. 2/ Large requests, and in particular any 'write' request, will not be queued by the current code and doing so would be undesirable. In many cases only a very sort wait is needed before the cache gets valid data. So, providing the underlying transport permits it by setting ->thread_wait, arrange to wait briefly for an upcall to be completed (as reflected in the clearing of CACHE_PENDING). If the short wait was not long enough and CACHE_PENDING is still set, fall back on the old approach. The 'thread_wait' value is set to 5 seconds when there are spare threads, and 1 second when there are no spare threads. These values are probably much higher than needed, but will ensure some forward progress. Note that as we only request an update for a non-valid item, and as non-valid items are updated in place it is extremely unlikely that cache_check will return -ETIMEDOUT. Normally cache_defer_req will sleep for a short while and then find that the item is_valid. Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2010-05-04Merge commit 'v2.6.34-rc6'J. Bruce Fields
Conflicts: fs/nfsd/nfs4callback.c
2010-05-03sunrpc: centralise most calls to svc_xprt_receivedNeil Brown
svc_xprt_received must be called when ->xpo_recvfrom has finished receiving a message, so that the XPT_BUSY flag will be cleared and if necessary, requeued for further work. This call is currently made in each ->xpo_recvfrom function, often from multiple different points. In each case it is the earliest point on a particular path where it is known that the protection provided by XPT_BUSY is no longer needed. However there are (still) some error paths which do not call svc_xprt_received, and requiring each ->xpo_recvfrom to make the call does not encourage robustness. So: move the svc_xprt_received call to be made just after the call to ->xpo_recvfrom(), and move it of the various ->xpo_recvfrom methods. This means that it may not be called at the earliest possible instant, but this is unlikely to be a measurable performance issue. Note that there are still other calls to svc_xprt_received as it is also needed when an xprt is newly created. Signed-off-by: NeilBrown <neilb@suse.de> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo
implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-29svcrpc: don't hold sv_lock over svc_xprt_put()J. Bruce Fields
svc_xprt_put() can call tcp_close(), which can sleep, so we shouldn't be holding this lock. In fact, only the xpt_list removal and the sv_tmpcnt decrement should need the sv_lock here. Reported-by: Mi Jinlong <mijinlong@cn.fujitsu.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2010-02-28Revert "sunrpc: move the close processing after do recvfrom method"J. Bruce Fields
This reverts commit b0401d725334a94d57335790b8ac2404144748ee, which moved svc_delete_xprt() outside of XPT_BUSY, and allowed it to be called after svc_xpt_recived(), removing its last reference and destroying it after it had already been queued for future processing. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2010-02-28Revert "sunrpc: fix peername failed on closed listener"J. Bruce Fields
This reverts commit b292cf9ce70d221c3f04ff62db5ab13d9a249ca8. The commit that it attempted to patch up, b0401d725334a94d57335790b8ac2404144748ee, was fundamentally wrong, and will also be reverted. Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2010-02-26sunrpc: remove unnecessary svc_xprt_putNeil Brown
The 'struct svc_deferred_req's on the xpt_deferred queue do not own a reference to the owning xprt. This is seen in svc_revisit which is where things are added to this queue. dr->xprt is set to NULL and the reference to the xprt it put. So when this list is cleaned up in svc_delete_xprt, we mustn't put the reference. Also, replace the 'for' with a 'while' which is arguably simpler and more likely to compile efficiently. Cc: Tom Tucker <tom@opengridcomputing.com> Signed-off-by: NeilBrown <neilb@suse.de> Cc: stable@kernel.org Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2010-01-26SUNRPC: NFS kernel APIs shouldn't return ENOENT for "transport not found"Chuck Lever
write_ports() converts svc_create_xprt()'s ENOENT error return to EPROTONOSUPPORT so that rpc.nfsd (in user space) can report an error message that makes sense. It turns out that several of the other kernel APIs rpc.nfsd use can also return ENOENT from svc_create_xprt(), by way of lockd_up(). On the client side, an NFSv2 or NFSv3 mount request can also return the result of lockd_up(). This error may also be returned during an NFSv4 mount request, since the NFSv4 callback service uses svc_create_xprt() to create the callback listener. An ENOENT error return results in a confusing error message from the mount command. Let's have svc_create_xprt() return EPROTONOSUPPORT instead of ENOENT. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2010-01-26SUNRPC: Bury "#ifdef IPV6" in svc_create_xprt()Chuck Lever
Clean up: Bruce observed we have more or less common logic in each of svc_create_xprt()'s callers: the check to create an IPv6 RPC listener socket only if CONFIG_IPV6 is set. I'm about to add another case that does just the same. If we move the ifdefs into __svc_xpo_create(), then svc_create_xprt() call sites can get rid of the "#ifdef" ugliness, and can use the same logic with or without IPv6 support available in the kernel. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2010-01-06Merge branch 'for-2.6.33' of git://linux-nfs.org/~bfields/linuxLinus Torvalds
* 'for-2.6.33' of git://linux-nfs.org/~bfields/linux: sunrpc: fix peername failed on closed listener nfsd: make sure data is on disk before calling ->fsync nfsd: fix "insecure" export option
2010-01-06sunrpc: fix peername failed on closed listenerXiaotian Feng
There're some warnings of "nfsd: peername failed (err 107)!" socket error -107 means Transport endpoint is not connected. This warning message was outputed by svc_tcp_accept() [net/sunrpc/svcsock.c], when kernel_getpeername returns -107. This means socket might be CLOSED. And svc_tcp_accept was called by svc_recv() [net/sunrpc/svc_xprt.c] if (test_bit(XPT_LISTENER, &xprt->xpt_flags)) { <snip> newxpt = xprt->xpt_ops->xpo_accept(xprt); <snip> So this might happen when xprt->xpt_flags has both XPT_LISTENER and XPT_CLOSE. Let's take a look at commit b0401d72, this commit has moved the close processing after do recvfrom method, but this commit also introduces this warnings, if the xpt_flags has both XPT_LISTENER and XPT_CLOSED, we should close it, not accpet then close. Signed-off-by: Xiaotian Feng <dfeng@redhat.com> Cc: J. Bruce Fields <bfields@fieldses.org> Cc: Neil Brown <neilb@suse.de> Cc: Trond Myklebust <Trond.Myklebust@netapp.com> Cc: David S. Miller <davem@davemloft.net> Cc: stable@kernel.org Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-12-16Merge branch 'for-2.6.33' of git://linux-nfs.org/~bfields/linuxLinus Torvalds
* 'for-2.6.33' of git://linux-nfs.org/~bfields/linux: (42 commits) nfsd: remove pointless paths in file headers nfsd: move most of nfsfh.h to fs/nfsd nfsd: remove unused field rq_reffh nfsd: enable V4ROOT exports nfsd: make V4ROOT exports read-only nfsd: restrict filehandles accepted in V4ROOT case nfsd: allow exports of symlinks nfsd: filter readdir results in V4ROOT case nfsd: filter lookup results in V4ROOT case nfsd4: don't continue "under" mounts in V4ROOT case nfsd: introduce export flag for v4 pseudoroot nfsd: let "insecure" flag vary by pseudoflavor nfsd: new interface to advertise export features nfsd: Move private headers to source directory vfs: nfsctl.c un-used nfsd #includes lockd: Remove un-used nfsd headers #includes s390: remove un-used nfsd #includes sparc: remove un-used nfsd #includes parsic: remove un-used nfsd #includes compat.c: Remove dependence on nfsd private headers ...
2009-11-29net: Move && and || to end of previous lineJoe Perches
Not including net/atm/ Compiled tested x86 allyesconfig only Added a > 80 column line or two, which I ignored. Existing checkpatch plaints willfully, cheerfully ignored. Signed-off-by: Joe Perches <joe@perches.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2009-11-23Revert "knfsd: avoid overloading the CPU scheduler with enormous load averages"J. Bruce Fields
This reverts commit 59a252ff8c0f2fa32c896f69d56ae33e641ce7ad. This helps in an entirely cached workload but not necessarily in workloads that require waiting on disk. Conflicts: include/linux/sunrpc/svc.h net/sunrpc/svc_xprt.c Reported-by: Simon Kirby <sim@hostway.ca> Tested-by: Jesper Krogh <jesper@krogh.cc> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-09-11nfsd41: sunrpc: Added rpc server-side backchannel handlingRahul Iyer
When the call direction is a reply, copy the xid and call direction into the req->rq_private_buf.head[0].iov_base otherwise rpc_verify_header returns rpc_garbage. Signed-off-by: Rahul Iyer <iyer@netapp.com> Signed-off-by: Mike Sager <sager@netapp.com> Signed-off-by: Marc Eshel <eshel@almaden.ibm.com> Signed-off-by: Benny Halevy <bhalevy@panasas.com> Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com> Signed-off-by: Andy Adamson <andros@netapp.com> Signed-off-by: Benny Halevy <bhalevy@panasas.com> [get rid of CONFIG_NFSD_V4_1] [sunrpc: refactoring of svc_tcp_recvfrom] [nfsd41: sunrpc: create common send routine for the fore and the back channels] [nfsd41: sunrpc: Use free_page() to free server backchannel pages] [nfsd41: sunrpc: Document server backchannel locking] [nfsd41: sunrpc: remove bc_connect_worker()] [nfsd41: sunrpc: Define xprt_server_backchannel()[ [nfsd41: sunrpc: remove bc_close and bc_init_auto_disconnect dummy functions] [nfsd41: sunrpc: eliminate unneeded switch statement in xs_setup_tcp()] [nfsd41: sunrpc: Don't auto close the server backchannel connection] [nfsd41: sunrpc: Remove unused functions] Signed-off-by: Alexandros Batsakis <batsakis@netapp.com> Signed-off-by: Ricardo Labiaga <Ricardo.Labiaga@netapp.com> Signed-off-by: Benny Halevy <bhalevy@panasas.com> [nfsd41: change bc_sock to bc_xprt] [nfsd41: sunrpc: move struct rpc_buffer def into a common header file] [nfsd41: sunrpc: use rpc_sleep in bc_send_request so not to block on mutex] [removed cosmetic changes] Signed-off-by: Benny Halevy <bhalevy@panasas.com> [sunrpc: add new xprt class for nfsv4.1 backchannel] [sunrpc: v2.1 change handling of auto_close and init_auto_disconnect operations for the nfsv4.1 backchannel] Signed-off-by: Alexandros Batsakis <batsakis@netapp.com> [reverted more cosmetic leftovers] [got rid of xprt_server_backchannel] [separated "nfsd41: sunrpc: add new xprt class for nfsv4.1 backchannel"] Signed-off-by: Benny Halevy <bhalevy@panasas.com> Cc: Trond Myklebust <trond.myklebust@netapp.com> [sunrpc: change idle timeout value for the backchannel] Signed-off-by: Alexandros Batsakis <batsakis@netapp.com> Signed-off-by: Benny Halevy <bhalevy@panasas.com> Acked-by: Trond Myklebust <trond.myklebust@netapp.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-08-27sunrpc: move the close processing after do recvfrom methodWei Yongjun
sunrpc: "Move close processing to a single place" (d7979ae4a050a45b78af51832475001b68263d2a) moved the close processing before the recvfrom method. This may cause the close processing never to execute. So this patch moves it to the right place. Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-08-25knfsd: Replace lock_kernel with a mutex in nfsd pool stats.Ryusei Yamaguchi
lock_kernel() in knfsd was replaced with a mutex. The later commit 03cf6c9f49a8fea953d38648d016e3f46e814991 ("knfsd: add file to export stats about nfsd pools") did not follow that change. This patch fixes the issue. Also move the get and put of nfsd_serv to the open and close methods (instead of start and stop methods) to allow atomic check and increment of reference count in the open method (where we can still return an error). Signed-off-by: Ryusei Yamaguchi <mandel59@gmail.com> Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp> Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Cc: Greg Banks <gnb@fmeh.org> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-07-12headers: smp_lock.h reduxAlexey Dobriyan
* Remove smp_lock.h from files which don't need it (including some headers!) * Add smp_lock.h to files which do need it * Make smp_lock.h include conditional in hardirq.h It's needed only for one kernel_locked() usage which is under CONFIG_PREEMPT This will make hardirq.h inclusion cheaper for every PREEMPT=n config (which includes allmodconfig/allyesconfig, BTW) Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-28NFSD: Prevent a buffer overflow in svc_xprt_names()Chuck Lever
The svc_xprt_names() function can overflow its buffer if it's so near the end of the passed in buffer that the "name too long" string still doesn't fit. Of course, it could never tell if it was near the end of the passed in buffer, since its only caller passes in zero as the buffer length. Let's make this API a little safer. Change svc_xprt_names() so it *always* checks for a buffer overflow, and change its only caller to pass in the correct buffer length. If svc_xprt_names() does overflow its buffer, it now fails with an ENAMETOOLONG errno, instead of trying to write a message at the end of the buffer. I don't like this much, but I can't figure out a clean way that's always safe to return some of the names, *and* an indication that the buffer was not long enough. The displayed error when doing a 'cat /proc/fs/nfsd/portlist' is "File name too long". Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-04-28net/sunrpc/svc_xprt.c: fix sparse warningsH Hartley Sweeten
Fix the following sparse warnings in net/sunrpc/svc_xprt.c. warning: symbol 'svc_recv' was not declared. Should it be static? warning: symbol 'svc_drop' was not declared. Should it be static? warning: symbol 'svc_send' was not declared. Should it be static? warning: symbol 'svc_close_all' was not declared. Should it be static? Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-04-06Merge branch 'for-2.6.30' of git://linux-nfs.org/~bfields/linuxLinus Torvalds
* 'for-2.6.30' of git://linux-nfs.org/~bfields/linux: (81 commits) nfsd41: define nfsd4_set_statp as noop for !CONFIG_NFSD_V4 nfsd41: define NFSD_DRC_SIZE_SHIFT in set_max_drc nfsd41: Documentation/filesystems/nfs41-server.txt nfsd41: CREATE_EXCLUSIVE4_1 nfsd41: SUPPATTR_EXCLCREAT attribute nfsd41: support for 3-word long attribute bitmask nfsd: dynamically skip encoded fattr bitmap in _nfsd4_verify nfsd41: pass writable attrs mask to nfsd4_decode_fattr nfsd41: provide support for minor version 1 at rpc level nfsd41: control nfsv4.1 svc via /proc/fs/nfsd/versions nfsd41: add OPEN4_SHARE_ACCESS_WANT nfs4_stateid bmap nfsd41: access_valid nfsd41: clientid handling nfsd41: check encode size for sessions maxresponse cached nfsd41: stateid handling nfsd: pass nfsd4_compound_state* to nfs4_preprocess_{state,seq}id_op nfsd41: destroy_session operation nfsd41: non-page DRC for solo sequence responses nfsd41: Add a create session replay cache nfsd41: create_session operation ...
2009-04-03nfsd: don't use the deferral service, return NFS4ERR_DELAYAndy Adamson
On an NFSv4.1 server cache miss that causes an upcall, NFS4ERR_DELAY will be returned. It is up to the NFSv4.1 client to resend only the operations that have not been processed. Initialize rq_usedeferral to 1 in svc_process(). It sill be turned off in nfsd4_proc_compound() only when NFSv4.1 Sessions are used. Note: this isn't an adequate solution on its own. It's acceptable as a way to get some minimal 4.1 up and working, but we're going to have to find a way to avoid returning DELAY in all common cases before 4.1 can really be considered ready. Signed-off-by: Andy Adamson <andros@netapp.com> Signed-off-by: Benny Halevy <bhalevy@panasas.com> [nfsd41: reverse rq_nodeferral negative logic] Signed-off-by: Benny Halevy <bhalevy@panasas.com> [sunrpc: initialize rq_usedeferral] Signed-off-by: Andy Adamson <andros@netapp.com> Signed-off-by: Benny Halevy <bhalevy@panasas.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-03-28SUNRPC: Change svc_create_xprt() to take a @family argumentChuck Lever
The sv_family field is going away. Pass a protocol family argument to svc_create_xprt() instead of extracting the family from the passed-in svc_serv struct. Again, as this is a listener socket and not an address, we make this new argument an "int" protocol family, instead of an "sa_family_t." Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-03-28SUNRPC: Clean up svc_find_xprt() calling sequenceChuck Lever
Clean up: add documentating comment and use appropriate data types for svc_find_xprt()'s arguments. This also eliminates a mixed sign comparison: @port was an int, while the return value of svc_xprt_local_port() is an unsigned short. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
2009-03-18knfsd: add file to export stats about nfsd poolsGreg Banks
Add /proc/fs/nfsd/pool_stats to export to userspace various statistics about the operation of rpc server thread pools. This patch is based on a forward-ported version of knfsd-add-pool-thread-stats which has been shipping in the SGI "Enhanced NFS" product since 2006 and which was previously posted: http://article.gmane.org/gmane.linux.nfs/10375 It has also been updated thus: * moved EXPORT_SYMBOL() to near the function it exports * made the new struct struct seq_operations const * used SEQ_START_TOKEN instead of ((void *)1) * merged fix from SGI PV 990526 "sunrpc: use dprintk instead of printk in svc_pool_stats_*()" by Harshula Jayasuriya. * merged fix from SGI PV 964001 "Crash reading pool_stats before nfsds are started". Signed-off-by: Greg Banks <gnb@sgi.com> Signed-off-by: Harshula Jayasuriya <harshula@sgi.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-03-18knfsd: avoid overloading the CPU scheduler with enormous load averagesGreg Banks
Avoid overloading the CPU scheduler with enormous load averages when handling high call-rate NFS loads. When the knfsd bottom half is made aware of an incoming call by the socket layer, it tries to choose an nfsd thread and wake it up. As long as there are idle threads, one will be woken up. If there are lot of nfsd threads (a sensible configuration when the server is disk-bound or is running an HSM), there will be many more nfsd threads than CPUs to run them. Under a high call-rate low service-time workload, the result is that almost every nfsd is runnable, but only a handful are actually able to run. This situation causes two significant problems: 1. The CPU scheduler takes over 10% of each CPU, which is robbing the nfsd threads of valuable CPU time. 2. At a high enough load, the nfsd threads starve userspace threads of CPU time, to the point where daemons like portmap and rpc.mountd do not schedule for tens of seconds at a time. Clients attempting to mount an NFS filesystem timeout at the very first step (opening a TCP connection to portmap) because portmap cannot wake up from select() and call accept() in time. Disclaimer: these effects were observed on a SLES9 kernel, modern kernels' schedulers may behave more gracefully. The solution is simple: keep in each svc_pool a counter of the number of threads which have been woken but have not yet run, and do not wake any more if that count reaches an arbitrary small threshold. Testing was on a 4 CPU 4 NIC Altix using 4 IRIX clients, each with 16 synthetic client threads simulating an rsync (i.e. recursive directory listing) workload reading from an i386 RH9 install image (161480 regular files in 10841 directories) on the server. That tree is small enough to fill in the server's RAM so no disk traffic was involved. This setup gives a sustained call rate in excess of 60000 calls/sec before being CPU-bound on the server. The server was running 128 nfsds. Profiling showed schedule() taking 6.7% of every CPU, and __wake_up() taking 5.2%. This patch drops those contributions to 3.0% and 2.2%. Load average was over 120 before the patch, and 20.9 after. This patch is a forward-ported version of knfsd-avoid-nfsd-overload which has been shipping in the SGI "Enhanced NFS" product since 2006. It has been posted before: http://article.gmane.org/gmane.linux.nfs/10374 Signed-off-by: Greg Banks <gnb@sgi.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-07SUNRPC: The sunrpc server code should not be used by out-of-tree modulesTrond Myklebust
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-07svc: Clean up deferred requests on transport destructionTom Tucker
A race between svc_revisit and svc_delete_xprt can result in deferred requests holding references on a transport that can never be recovered because dead transports are not enqueued for subsequent processing. Check for XPT_DEAD in revisit to clean up completing deferrals on a dead transport and sweep a transport's deferred queue to do the same for queued but unprocessed deferrals. Signed-off-by: Tom Tucker <tom@opengridcomputing.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-07svc: Move kfree of deferral record to common codeTom Tucker
The rqstp structure has a pointer to a svc_deferred_req record that is allocated when requests are deferred. This record is common to all transports and can be freed in common code. Move the kfree of the rq_deferred to the common svc_xprt_release function. This also fixes a memory leak in the RDMA transport which does not kfree the dr structure in it's version of the xpo_release_rqst callback. Signed-off-by: Tom Tucker <tom@opengridcomputing.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2009-01-06sunrpc: add sv_maxconn field to svc_serv (try #3)Jeff Layton
svc_check_conn_limits() attempts to prevent denial of service attacks by having the service close old connections once it reaches a threshold. This threshold is based on the number of threads in the service: (serv->sv_nrthreads + 3) * 20 Once we reach this, we drop the oldest connections and a printk pops to warn the admin that they should increase the number of threads. Increasing the number of threads isn't an option however for services like lockd. We don't want to eliminate this check entirely for such services but we need some way to increase this limit. This patch adds a sv_maxconn field to the svc_serv struct. When it's set to 0, we use the current method to calculate the max number of connections. RPC services can then set this on an as-needed basis. Signed-off-by: Jeff Layton <jlayton@redhat.com> Acked-by: Neil Brown <neilb@suse.de> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-09-29SUNRPC: Use proper INADDR_ANY when setting up RPC services on IPv6Chuck Lever
Teach svc_create_xprt() to use the correct ANY address for AF_INET6 based RPC services. No caller uses AF_INET6 yet. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-05-19svc: Remove unused header files from svc_xprt.cTom Tucker
This cosmetic patch removes unused header files that svc_xprt.c inherited from svcsock.c Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
2008-05-19svc: Remove extra check for XPT_DEAD bit in svc_xprt_enqueueTom Tucker
Remove a redundant check for the XPT_DEAD bit in the svc_xprt_enqueue function. This same bit is checked below while holding the pool lock and prints a debug message if found to be dead. Signed-off-by: Tom Tucker <tom@opengridcomputing.com>
2008-04-23SUNRPC: allow svc_recv to break out of 500ms sleep when alloc_page failsJeff Layton
svc_recv() calls alloc_page(), and if it fails it does a 500ms uninterruptible sleep and then reattempts. There doesn't seem to be any real reason for this to be uninterruptible, so change it to an interruptible sleep. Also check for kthread_stop() and signalled() after setting the task state to avoid races that might lead to sleeping after kthread_stop() wakes up the task. I've done some very basic smoke testing with this, but obviously it's hard to test the actual changes since this all depends on an alloc_page() call failing. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-04-23SUNRPC: have svc_recv() check kthread_should_stop()Jeff Layton
When using kthreads that call into svc_recv, we want to make sure that they do not block there for a long time when we're trying to take down the kthread. This patch changes svc_recv() to check kthread_should_stop() at the same places that it checks to see if it's signalled(). Also check just before svc_recv() tries to schedule(). By making sure that we check it just after setting the task state we can avoid having to use any locking or signalling to ensure it doesn't block for a long time. There's still a chance of a 500ms sleep if alloc_page() fails, but that should be a rare occurrence and isn't a terribly long time in the context of a kthread being taken down. Signed-off-by: Jeff Layton <jlayton@redhat.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-03-17[NET] endianness noise: INADDR_ANYAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: David S. Miller <davem@davemloft.net>
2008-02-01SUNRPC: Move exported symbol definitions after function declaration part 2Trond Myklebust
Do it for the server code... Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01svc: Add svc_xprt_names service to replace svc_sock_namesTom Tucker
Create a transport independent version of the svc_sock_names function. The toclose capability of the svc_sock_names service can be implemented using the svc_xprt_find and svc_xprt_close services. Signed-off-by: Tom Tucker <tom@opengridcomputing.com> Acked-by: Neil Brown <neilb@suse.de> Reviewed-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Greg Banks <gnb@sgi.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01knfsd: Support adding transports by writing portlist fileTom Tucker
Update the write handler for the portlist file to allow creating new listening endpoints on a transport. The general form of the string is: <transport_name><space><port number> For example: echo "tcp 2049" > /proc/fs/nfsd/portlist This is intended to support the creation of a listening endpoint for RDMA transports without adding #ifdef code to the nfssvc.c file. Transports can also be removed as follows: '-'<transport_name><space><port number> For example: echo "-tcp 2049" > /proc/fs/nfsd/portlist Attempting to add a listener with an invalid transport string results in EPROTONOSUPPORT and a perror string of "Protocol not supported". Attempting to remove an non-existent listener (.e.g. bad proto or port) results in ENOTCONN and a perror string of "Transport endpoint is not connected" Signed-off-by: Tom Tucker <tom@opengridcomputing.com> Acked-by: Neil Brown <neilb@suse.de> Reviewed-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Greg Banks <gnb@sgi.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01svc: Add svc API that queries for a transport instanceTom Tucker
Add a new svc function that allows a service to query whether a transport instance has already been created. This is used in lockd to determine whether or not a transport needs to be created when a lockd instance is brought up. Specifying 0 for the address family or port is effectively a wild-card, and will result in matching the first transport in the service's list that has a matching class name. Signed-off-by: Tom Tucker <tom@opengridcomputing.com> Acked-by: Neil Brown <neilb@suse.de> Reviewed-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Greg Banks <gnb@sgi.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01svc: Add /proc/sys/sunrpc/transport filesTom Tucker
Add a file that when read lists the set of registered svc transports. Signed-off-by: Tom Tucker <tom@opengridcomputing.com> Acked-by: Neil Brown <neilb@suse.de> Reviewed-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Greg Banks <gnb@sgi.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01svc: Add transport hdr size for defer/revisitTom Tucker
Some transports have a header in front of the RPC header. The current defer/revisit processing considers only the iov_len and arg_len to determine how much to back up when saving the original request to revisit. Add a field to the rqstp structure to save the size of the transport header so svc_defer can correctly compute the start of a request. Signed-off-by: Tom Tucker <tom@opengridcomputing.com> Acked-by: Neil Brown <neilb@suse.de> Reviewed-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Greg Banks <gnb@sgi.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01svc: Move the xprt independent code to the svc_xprt.c fileTom Tucker
This functionally trivial patch moves all of the transport independent functions from the svcsock.c file to the transport independent svc_xprt.c file. In addition the following formatting changes were made: - White space cleanup - Function signatures on single line - The inline directive was removed - Lines over 80 columns were reformatted - The term 'socket' was changed to 'transport' in comments - The SMP comment was moved and updated. Signed-off-by: Tom Tucker <tom@opengridcomputing.com> Acked-by: Neil Brown <neilb@suse.de> Reviewed-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Greg Banks <gnb@sgi.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01svc: Move create logic to common codeTom Tucker
Move the svc transport list logic into common transport creation code. Refactor this code path to make the flow of control easier to read. Move the setting and clearing of the BUSY_BIT during transport creation to common code. Signed-off-by: Tom Tucker <tom@opengridcomputing.com> Acked-by: Neil Brown <neilb@suse.de> Reviewed-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Greg Banks <gnb@sgi.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01svc: Move the sockaddr information to svc_xprtTom Tucker
This patch moves the transport sockaddr to the svc_xprt structure. Convenience functions are added to set and get the local and remote addresses of a transport from the transport provider as well as determine the length of a sockaddr. A transport is responsible for setting the xpt_local and xpt_remote addresses in the svc_xprt structure as part of transport creation and xpo_accept processing. This cannot be done in a generic way and in fact varies between TCP, UDP and RDMA. A set of xpo_ functions (e.g. getlocalname, getremotename) could have been added but this would have resulted in additional caching and copying of the addresses around. Note that the xpt_local address should also be set on listening endpoints; for TCP/RDMA this is done as part of endpoint creation. For connected transports like TCP and RDMA, the addresses never change and can be set once and copied into the rqstp structure for each request. For UDP, however, the local and remote addresses may change for each request. In this case, the address information is obtained from the UDP recvmsg info and copied into the rqstp structure from there. A svc_xprt_local_port function was also added that returns the local port given a transport. This is used by svc_create_xprt when returning the port associated with a newly created transport, and later when creating a generic find transport service to check if a service is already listening on a given port. Signed-off-by: Tom Tucker <tom@opengridcomputing.com> Acked-by: Neil Brown <neilb@suse.de> Reviewed-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Greg Banks <gnb@sgi.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
2008-02-01svc: Make deferral processing xprt independentTom Tucker
This patch moves the transport independent sk_deferred list to the svc_xprt structure and updates the svc_deferred_req structure to keep pointers to svc_xprt's directly. The deferral processing code is also moved out of the transport dependent recvfrom functions and into the generic svc_recv path. Signed-off-by: Tom Tucker <tom@opengridcomputing.com> Acked-by: Neil Brown <neilb@suse.de> Reviewed-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Greg Banks <gnb@sgi.com> Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>