summaryrefslogtreecommitdiffstats
path: root/xlators/features/changelog/src/changelog-rpc.c
Commit message (Collapse)AuthorAgeFilesLines
* changelog/rpc: Fix rpc_clnt_t mem leaksKotresh HR2016-07-271-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Backport of http://review.gluster.org/13658 PROBLEM: 1. Freeing up rpc_clnt object might lead to crashes. Well, it was not a necessity to free rpc-clnt object till now because all the existing use cases needs to reconnect back on disconnects. Hence timer code was not taking ref on rpc-clnt object. Glusterd had some use-cases that led to crash due to ping-timer and they fixed only those code paths that involve ping-timer. Now, since changelog has an use-case where rpc-clnt need to be freed up, we need to fix timer code to take refs 2. In changelog, because of issue 1, only mydata was being freed which is incorrect. And there are races where rpc-clnt object would access the freed mydata which would lead to crashes. Since changelog xlator resides on brick side and is long living process, if multiple libgfchangelog consumers register to changelog and disconnect/reconnect mulitple times, it would result in leak of 'rpc-clnt' object for every connect/disconnect. SOLUTION: 1. Handle ref/unref of 'rpc_clnt' structure in timer functions properly. 2. In changelog, unref 'rpc_clnt' in RPC_CLNT_DISCONNECT after disabling timers and free mydata on RPC_CLNT_DESTROY. RPC SETUP IN CHANGELOG: 1. changelog xlator initiates rpc server say 'changelog_rpc_server' 2. libgfchangelog initiates one rpc server say 'libgfchangelog_rpc_server' 3. libgfchangelog initiates rpc client and connects to 'changelog_rpc_server' 4. In return changelog_rpc_server initiates a rpc client and connects back to 'libgfchangelog_rpc_server' REF/UNREF HANDLING IN TIMER FUNCTIONS: Let's say rpc clnt refcount = 1 1. Take the ref before reigstering callback to timer queue >>>> rpc_clnt_ref (say ref count becomes = 2) 2. Register a callback to timer say 'callback1' 3. If register fails: >>>> rpc_clnt_unref (ref count = 1) 4. On timer expiration, 'callback1' gets called. So unref rpc clnt at the end in 'callback1'. This is corresponding to ref taken in step 1 >>>> rpc_clnt_unref (ref count = 1) 5. The cycle from step-1 to step-4 continues....until timer cancel event happens 6. timer cancel of say 'callback1' If timer cancel fails: Do nothing, Step-4 would have unrefd If timer cancel succeeds: >>>> rpc_clnt_unref (ref count = 1) Change-Id: I91389bc511b8b1a17824941970ee8d2c29a74a09 BUG: 1359363 Signed-off-by: Kotresh HR <khiremat@redhat.com> (cherry picked from commit 637ce9e2e27e9f598a4a6c5a04cd339efaa62076) Reviewed-on: http://review.gluster.org/14993 CentOS-regression: Gluster Build System <jenkins@build.gluster.org> Smoke: Gluster Build System <jenkins@build.gluster.org> NetBSD-regression: NetBSD Build System <jenkins@build.gluster.org> Reviewed-by: Raghavendra G <rgowdapp@redhat.com>
* all: reduce "inline" usageKaleb S KEITHLEY2016-01-181-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | There are three kinds of inline functions: plain inline, extern inline, and static inline. All three have been removed from .c files, except those in "contrib" which aren't our problem. Inlines in .h files, which are overwhelmingly "static inline" already, have generally been left alone. Over time we should be able to "lower" these into .c files, but that has to be done in a case-by-case fashion requiring more manual effort. This part was easy to do automatically without (as far as I can tell) any ill effect. In the process, several pieces of dead code were flagged by the compiler, and were removed. backport of Change-Id: I56a5e614735c9e0a6ee420dab949eac22e25c155, http://review.gluster.org/11769, BUG: 1245331 Change-Id: Iba1efb0bc578ea4a5e9bf76b7bd93dc1be9eba44 BUG: 1283302 Signed-off-by: Kaleb S KEITHLEY <kkeithle@redhat.com> Reviewed-on: http://review.gluster.org/12646 Smoke: Gluster Build System <jenkins@build.gluster.com> NetBSD-regression: NetBSD Build System <jenkins@build.gluster.org> CentOS-regression: Gluster Build System <jenkins@build.gluster.com> Reviewed-by: Niels de Vos <ndevos@redhat.com>
* features/changelog: Remove inline keyword to avoid warnings (gcc v5.1.1)v3.7.1Anoop C S2015-06-011-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | Backport of http://review.gluster.org/11004 When compiled with gcc5, following warnings were displayed and volume start failed: changelog-helpers.h:499:1: warning: inline function 'changelog_dispatch_event' declared but never defined changelog_dispatch_event (xlator_t *, changelog_priv_t *, changelog_event_t *); gf-changelog-journal-handler.c:692:17: warning: 'list_add_tail' is static but used in inline function 'gf_changelog_queue_journal' which is not static list_add_tail (&entry->list, &jnl_proc->entries); Fix is to remove the keyword from function prototype and definitions. Change-Id: I188b35b7ca087a94d7a48a052b05a6d845e3b74b BUG: 1226853 Signed-off-by: Anoop C S <achiraya@redhat.com> Reviewed-on: http://review.gluster.org/11030 Tested-by: NetBSD Build System <jenkins@build.gluster.org> Tested-by: Gluster Build System <jenkins@build.gluster.com> Reviewed-by: Venky Shankar <vshankar@redhat.com>
* rpc: Maintain separate xlator pointer in 'rpcsvc_state'Kotresh HR2015-05-051-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The structure 'rpcsvc_state', which maintains rpc server state had no separate pointer to track the translator. It was using the mydata pointer itself. So callers were forced to send xlator pointer as mydata which is opaque (void pointer) by function prototype. 'rpcsvc_register_init' is setting svc->mydata with xlator pointer. 'rpcsvc_register_notify' is overwriting svc->mydata with mydata pointer. And rpc interprets svc->mydata as xlator pointer internally. If someone passes non xlator structure pointer to rpcsvc_register_notify as libgfchangelog currently does, it might corrupt mydata. So interpreting opaque mydata as xlator pointer is incorrect as it is caller's choice to send mydata as any type of data to 'rpcsvc_register_notify'. Maintaining two different pointers in 'rpcsvc_state' for xlator and mydata solves the issue. BUG: 1218381 Change-Id: I4c28937a30845e3f41b6fc7a09036149c816659b Signed-off-by: Kotresh HR <khiremat@redhat.com> Reviewed-on: http://review.gluster.org/10366 Reviewed-on: http://review.gluster.org/10534 Tested-by: Gluster Build System <jenkins@build.gluster.com> Tested-by: NetBSD Build System Reviewed-by: Aravinda VK <avishwan@redhat.com> Reviewed-by: Vijay Bellur <vbellur@redhat.com>
* features/changelog: RPC'fy {libgf}changelogVenky Shankar2015-03-181-0/+300
This patch introduces RPC based communication between the changelog translator and libgfchangelog. It replaces the old pathetic stream based interaction that existed earlier (due to time constraints :-/). Changelog, upon initialization starts a RPC server (rpcsvc) allowing clients to invoke a probe API as a bootup mechanism to request for event notifications. During probe, clients can choose an event filter specifying the type(s) of events they are interested in. As of now there is no way to change the event notification set once the probe RPC call is made, but that is easier to implement. The actual event notifications is done on a separate RPC session. The client (libgfchangelog) itself starts and RPC server which the changelog translator "connects back" during probe. Notifications are dispatched by a bunch of threads from the server (translator) and the client optionally orders them if ordered notifications are requried. FOPs fill in their respective event details in a buffer (rot-buffs to be particular) and a bunch of threads (consumers) swap the buffers out of roatation and dispatch them via RPC. To avoid writer starvation, then number of dispatcher threads is one less than the number of buffer list in rot-buffs.x libgfchangelog becomes purely callback based -- upon event notification from the server (and re-ordering them if required) invoke a callback routine specified by consumer(s). A major part of the patch is also aimed at providing backward compatibility for geo-replication, which was one of the main consumer of the stream based API. Also, this patch does not\ "turn on" event notifications for all fops, just a bunch which is currently in requirement. Another pain point is that the server does not filter events before dispatching it to the clients. That load is taken up by the client itself (although it's done at the library layer rather than making it hard on the callback implementor). This needs improvement and care needs to be taken to not load the server up with expensive filtering mechanisms. Change-Id: Ibf60a432b68f2dfa60c6f9add2bcfd37a9c41395 BUG: 1170075 Signed-off-by: Venky Shankar <vshankar@redhat.com> Reviewed-on: http://review.gluster.org/9708 Reviewed-by: Jeff Darcy <jdarcy@redhat.com> Tested-by: Gluster Build System <jenkins@build.gluster.com> Reviewed-by: Vijay Bellur <vbellur@redhat.com>