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* build: Mac OS X build issues, no spinlock, need sys_lgetxattrKaleb S. KEITHLEY2015-07-051-1/+1
| | | | | | | | | | | | use regular locks, use our syscall wrappers in libglusterfs Change-Id: I7e0d00956366806af041b69b65d1f169aa0d2ae2 BUG: 1238793 Signed-off-by: Kaleb S. KEITHLEY <kkeithle@redhat.com> Reviewed-on: http://review.gluster.org/11515 Tested-by: Gluster Build System <jenkins@build.gluster.com> Reviewed-by: Niels de Vos <ndevos@redhat.com> Tested-by: NetBSD Build System <jenkins@build.gluster.org>
* features/bitrot: cleanup, v2Venky Shankar2015-06-252-3/+9
| | | | | | | | | | | | | | | This patch uses "cleanup, v1" infrastrcuture to cleanup scrubber (data structures, threads, timers, etc..) on brick disconnection. Signer is not cleaned up yet: probably would be done as part of another patch. Change-Id: I78a92b8a7f02b2f39078aa9a5a6b101fc499fd70 BUG: 1231619 Signed-off-by: Venky Shankar <vshankar@redhat.com> Reviewed-on: http://review.gluster.org/11148 Tested-by: NetBSD Build System <jenkins@build.gluster.org> Tested-by: Gluster Build System <jenkins@build.gluster.com> Reviewed-by: Raghavendra Bhat <raghavendra@redhat.com>
* contrib/timer-wheel: fix deadlock in del_timer()Venky Shankar2015-06-021-1/+1
| | | | | | | | | | | | | | | | | commit eaf3bfa added mod_timers() and successfully screwed up del_timer() by incorrectly wrapping it within double lock blocks. del_timer() was included before the above commit for the sake of timer API completion, thankfully noone used it till now. Change-Id: I07a454a216cf09dbb84777a23630e74a1e7f2830 BUG: 1227449 Signed-off-by: Venky Shankar <vshankar@redhat.com> Reviewed-on: http://review.gluster.org/11050 Reviewed-by: Niels de Vos <ndevos@redhat.com> Tested-by: NetBSD Build System <jenkins@build.gluster.org> Tested-by: Gluster Build System <jenkins@build.gluster.com>
* contrib/timer-wheel: mod_timer() and friendsVenky Shankar2015-05-282-5/+89
| | | | | | | | | | | | | | | | | | | Couple of timer-wheel api's to modify timer expiry times: mod_timer() mod_timer_pending() Both the api's perform almost the same job with one minute difference: mod_timer_pending() modifies timer expiry only if the timer is pending (i.e. being tracked in timer-wheel). Change-Id: Iae64934854ccfd6b081b849bff998ae3c3021bac BUG: 1224596 Signed-off-by: Venky Shankar <vshankar@redhat.com> Reviewed-on: http://review.gluster.org/10892 Tested-by: NetBSD Build System Reviewed-by: Niels de Vos <ndevos@redhat.com> Tested-by: Gluster Build System <jenkins@build.gluster.com>
* core: Global timer-wheelVenky Shankar2015-04-261-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | Instantiate a process wide global instance of the timer wheel data structure. Spawning glusterfs* process with option arg "--global-timer-wheel" instantiates a global instance of timer-wheel under global context (->ctx). Translators can make use of this process wide instance [via a call to glusterfs_global_timer_wheel()] instead of maintaining an instance of their own and possibly consuming more memory. Linux kernel too has a single instance of timer wheel where subsystems such as IO, networking, etc.. make use of. Bitrot daemon would be early consumers of this: bitrot translator instances for multiple volumes would track objects belonging to their respective bricks in this global expiry tracking data structure. This is also a first step to move GlusterFS timer mechanism to use timer-wheel. Change-Id: Ie882df607e07acaced846ea269ebf1ece306d6ae BUG: 1170075 Signed-off-by: Venky Shankar <vshankar@redhat.com> Reviewed-on: http://review.gluster.org/10380 Tested-by: NetBSD Build System Reviewed-by: Vijay Bellur <vbellur@redhat.com> Tested-by: Gluster Build System <jenkins@build.gluster.com>
* contrib/timer-wheel: import linux kernel timer-wheelVenky Shankar2015-03-183-0/+417
This patch imports timer-wheel[1] algorithm from the linux kernel (~/kernel/time/timer.c) with some modifications. Timer-wheel is an efficent way to track millions of timers for expiry. This is a variant of the simple but RAM heavy approach of having a list (timer bucket) for every future second. Timer-wheel categorizes every future second into a logarithmic array of arrays. This is done by splitting the 32 bit "timeout" value into fixed "sliced" bits, thereby each category has a fixed size array to which buckets are assigned. A classic split would be 8+6+6+6 (used in this patch) which results in 256+64+64+64 == 512 buckets. Therefore, the entire 32 bit futuristic timeouts have been mapped into 512 buckets. [ NOTE: There are other possible splits, such as "8+8+8+8", but this patch sticks to the widely used and tested default. ] Therfore, the first category "holds" timers whose expiry range is between 1..256, the next cateogry holds 257..16384, third category 16385..1048576 and so on. When timers are added, unless it's in the first category, timers with different timeouts could end up in the same bucket. This means that the timers are "partially sorted" -- sorted in their highest bits. The expiry code walks the first array of buckets and exprires any pending timers (1..256). Next, at time value 257, timers in the first bucket of the second array is "cascaded" onto the first category and timers are placed into respective buckets according to the thier timeout values. Cascading "brings down" the timers timeout to the coorect bucket of their respective category. Therefore, timers are sorted by their highest bits of the timeout value and then by the lower bits too. [1] https://lwn.net/Articles/152436/ Change-Id: I1219abf69290961ae9a3d483e11c107c5f49c4e3 BUG: 1170075 Signed-off-by: Venky Shankar <vshankar@redhat.com> Reviewed-on: http://review.gluster.org/9707 Reviewed-by: Vijay Bellur <vbellur@redhat.com> Tested-by: Vijay Bellur <vbellur@redhat.com>