Initial requests: paging requests which haven't been yet transmitted
Retrans requests: paging requests which have already been transmitted at
least once.
Until now one queue was used (llist) to store both. The initial requests
were stored at the start of the queue in FIFO order. After the last
initial requests, the retrans requests followed also in FIFO.
This ordering was used in order to prioritze scheduling of initial
paging requests over retransmit paging requests.
In the end, having both types in the same list only make code handling
the list more complex.
Hence, this patch splits the shared llist into 2 llists.
Related: SYS#6200
Change-Id: Ib68f2169e3790aea4ac77ec20ad79f242b7c2747
This allows configuring the maximum delay of paging requests to be
queued according to other parameters, such as MSC paging request
timeouts, etc.
Related: OS#5552
Change-Id: Ia556ef4e474e6a2d0d1618bab680a3330a3c062b
This allows havily decreasing the algorithmic cost of removing all
pending active paging requests for a given subscriber once it answers
on a given BTS.
Beforehand, the whole paging queue of all BTS were iterated. Now, only
the active requests for that subscriber are iterated.
Related: SYS#6200
Change-Id: I831d0fe01d7812c34500362b90f47cd65645b666
This way we avoid triggering timers and doing extra poll loops for each
BTS which is configured but not up. It also has the effect of removing
logging about estimating paging buffers for BTS which are down, which
can be confusing.
Furthermore, since work is delayed until the TRX and cell in general is
configured, the first estimation is properly done now since the correct
configuration is in place at that time.
Related: SYS#5922
Change-Id: I1b5b1a98115b4e9d821eb3330fc5b970a0e78a44
Reaching this point will only make system load (CPU, mem) grow, making
it hard for the process to keep up with work to do, with no benefit
since the requests will anyway be scheduled too late.
Related: SYS#5922
Change-Id: I6523c6816a4d16b71084d004e979be40cf0aeeb0
We want to recalculate the timer based on last time the work_timer was
triggered (that is, the time when the worker re-armed the pag req to
retransmit). We don't want to recalculate based on the last time the pag
ret tro retransmit was scheduled.
In loaded paging queue, there's lots of retrans (let's say 200) and it
may take more than 500ms to actually retransmit them. That means in most
cases we could end up in a situation where only pag req to retrans where
in the queue, hitting this recalculate path. Since the 500ms were for
sure elapsed, that would most probably schedule the work_timer at {0,0}
for each new paging request that arrived. As a result, the worker would
be scheduled lots of times per second (once for each new req arriving)
and only submitting 1 pag req (the new one) plus potentially 1 or
serveral pag req to retransmit.
In summary, there was not throthling applied in the scenario where only
pag req to retransmit where in the queue and new pag reqs kept arriving.
This incurrs into augmented paging throughput and also augmented
frequency of polls().
Related: OS#5922
Fixes: 4821c9f4df
Change-Id: I7ce6f436286b50dc31331d218ff256cf7be3f619
Before this patch, on each BTS a 500ms timer was used to schedule some
work, sending up to 20 paging requests verytime.
This means, however, for an initial paging request it may take up to
500ms delay to be scheduled to the BTS, which is huge.
While we still want to maintain this 500ms interval for retransmits, it
doesn't make sense to wait that much for other cases. It's far better
sending less requests (10 instead of 20) every half time (250ms instead
of 500ms), since it will spread the load and paging more over time,
allowing for other work to be done in the middle.
Change-Id: I7a1297452cc4734b6ee8c38fb94cf32f38d57c3d
During LCS development, I'm getting use count bugs and would like to see use
token strings to figure it out.
Change-Id: I29bf60059d4cf7bb99a00753e6cdc149baf95f94
To distinguish between the CN requiring a Complete Layer 3 response, or just
the BSC requiring a TA, allow recording a separate for-LCS paging reason.
Change-Id: Ib28d1599ae4e483727398859d07de4490fbc31f0
Allow starting a paging from elsewhere than a BSSMAP Paging Request. For
upcoming Location Services (LCS), a BSSLAP TA Request from the SMLC may require
triggering a Paging.
Change-Id: Iaff91584699d163bd1963927280ff3a8ddd43073
For LCS, I would like to add an enum indicating the paging reason. Instead of
modifying extremely many function signatures to pass the reason across all
levels of paging, introduce a struct combining these.
Change-Id: I27ca78fc6ff8ef1101554c0a8429e34945ca6f3c
Instead of iterating the llist of gsm_paging_requests first to find an MSC, and
then again right away to mark the paging as served, do both in the same step.
Change-Id: I447e61afc9934f3a5a82f6076e41c155d3328041
We can now either page an invidual BTS directly or page several BTS in a
given location area. This decision is taken based on the contents of the
cell identifier list in the paging request. Select a set of BTS for paging
while processing the cell identifier list, rather than requiring the
paging layer to loop over all BTS in the MSC.
This change requires some adjustment in bssap_test. In particular,
this test must now add a BTS to its network in order to pass.
The purpose of this change is to make the layering a bit cleaner.
There is one functional change: We no longer abort paging if paging fails
for a particular BTS. Instead, we keep trying to page on other BTS.
Change-Id: Ic1c72c7f83e53988eb9fedf314b1dc459836833d
Suggested-by: Harald Welte
Depends: Ic7772e75c3d7fb0df6e17e118bb33b3248352d4d
Related: OS#2753
When the MSC has lost its state and issues a RESET, we should not only
clear all ongoing radio connections, but we should also stop any paging.
There's no point in paging a subscriber if the MSC doesn't know about
this paging anymore.
Change-Id: If3f53d3bb66ad2dc02db823cb813590c6b59c700
Closes: OS#2736
The call-back was needed inside the NITB to determine which part (CC,
SMS, ...) had triggered a given paging. A pure BSC doesn't need that
feature, so let's get rid of it.
The 'void *cbfn_data' is replaced with a 'struct bsc_msc_data *', as
all callers use it with that type.
Change-Id: I8839e8338d3ad1a91b41e687e8412fcdca3fd9ab
Pau Espin
Harald Welte
Neels Hofmeyr