Commit Graph

11 Commits

Author SHA1 Message Date
Jan Glauber
cf9a031c2c [S390] qdio: merge AI tasklet into interrupt handler
Since the adapter interrupt tasklet only schedules the queue tasklets
and contains no code that requires serialization in can be merged
with the adapter interrupt handler. That possibly safes some CPU
cycles.

Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-06-22 12:08:20 +02:00
Jan Glauber
60b5df2f12 [S390] qdio: move adapter interrupt tasklet code
Move the adapter interrupt tasklet function to the qdio main code
since all the functions used by the tasklet are located there.

Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-06-22 12:08:19 +02:00
Jan Glauber
9c8a08d7a7 [S390] qdio: merge inbound and outbound handler functions
The inbound and outbound handlers are nearly identical if the outbound
handler uses first_to_check as end index instead of last_move. Since both
values are identical at that point the handlers can be merged.

Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26 15:24:22 +01:00
Jan Glauber
9e890ad880 [S390] qdio: tasklet termination in case of module unload
If the qdio module is unloaded the tiqdio tasklet must be terminated
by tasklet_kill. Move the tasklet_kill after the unregistration of
the adapter interrupt so the tiqdio tasklet will not be scheduled
anymore before calling tasklet_kill.

Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26 15:24:21 +01:00
Jan Glauber
c38f960809 [S390] qdio: proper kill of qdio tasklets
The queue tasklets were stopped with tasklet_disable. Although tasklet_disable
prevents the tasklet from beeing executed it is still possible that a tasklet
is scheduled on a CPU at that point. A following qdio_establish calls
tasklet_init which clears the tasklet count and the tasklet state leading to
the following Oops:

    <2>kernel BUG at kernel/softirq.c:392!
    <4>illegal operation: 0001 [#1] SMP
    <4>Modules linked in: iptable_filter ip_tables x_tables dm_round_robin dm_multipath scsi_dh sg sd_mod crc_t10dif nfs lockd nfs
_acl sunrpc fuse loop dm_mod qeth_l3 ipv6 zfcp qeth scsi_transport_fc qdio scsi_tgt scsi_mod chsc_sch ccwgroup dasd_eckd_mod dasdm
od ext3 mbcache jbd
    <4>Supported: Yes
    <4>CPU: 0 Not tainted 2.6.27.13-1.1.mz13-default #1
    <4>Process blast.LzS_64 (pid: 16445, task: 000000006cc02538, ksp: 000000006cb67998)
    <4>Krnl PSW : 0704c00180000000 00000000001399f4 (tasklet_action+0xc8/0x1d4)
    <4>           R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:0 PM:0 EA:3
    <4>Krnl GPRS: ffffffff00000030 0000000000000002 0000000000000002 fffffffffffffffe
    <4>           000000000013aabe 00000000003b6a18 fffffffffffffffd 0000000000000000
    <4>           00000000006705a8 000000007d0914a8 000000007d0914b0 000000007fecfd30
    <4>           0000000000000000 00000000003b63e8 000000007fecfd90 000000007fecfd30
    <4>Krnl Code: 00000000001399e8: b9200021            cgr     %r2,%r1
    <4>           00000000001399ec: a7740004            brc     7,1399f4
    <4>           00000000001399f0: a7f40001            brc     15,1399f2
    <4>          >00000000001399f4: c0100027e8ee        larl    %r1,636bd0
    <4>           00000000001399fa: bf1f1008            icm     %r1,15,8(%r1)
    <4>           00000000001399fe: a7840019            brc     8,139a30
    <4>           0000000000139a02: c0300027e8ef        larl    %r3,636be0
    <4>           0000000000139a08: e3c030000004        lg      %r12,0(%r3)
    <4>Call Trace:
    <4>([<0000000000139c12>] tasklet_hi_action+0x112/0x1d4)
    <4> [<000000000013aabe>] __do_softirq+0xde/0x1c4
    <4> [<000000000010fa2e>] do_softirq+0x96/0xb0
    <4> [<000000000013a8d8>] irq_exit+0x70/0xcc
    <4> [<000000000010d1d8>] do_extint+0xf0/0x110
    <4> [<0000000000113b10>] ext_no_vtime+0x16/0x1a
    <4> [<000003e0000a3662>] ext3_dirty_inode+0xe6/0xe8 [ext3]
    <4>([<00000000001f6cf2>] __mark_inode_dirty+0x52/0x1d4)
    <4> [<000003e0000a44f0>] ext3_ordered_write_end+0x138/0x190 [ext3]
    <4> [<000000000018d5ec>] generic_perform_write+0x174/0x230
    <4> [<0000000000190144>] generic_file_buffered_write+0xb4/0x194
    <4> [<0000000000190864>] __generic_file_aio_write_nolock+0x418/0x454
    <4> [<0000000000190ee2>] generic_file_aio_write+0x76/0xe4
    <4> [<000003e0000a05c2>] ext3_file_write+0x3e/0xc8 [ext3]
    <4> [<00000000001cc2fe>] do_sync_write+0xd6/0x120
    <4> [<00000000001ccfc8>] vfs_write+0xac/0x184
    <4> [<00000000001cd218>] SyS_write+0x68/0xe0
    <4> [<0000000000113402>] sysc_noemu+0x10/0x16
    <4> [<0000020000043188>] 0x20000043188
    <4>Last Breaking-Event-Address:
    <4> [<00000000001399f0>] tasklet_action+0xc4/0x1d4
    <6>qdio: 0.0.c61b ZFCP on SC f67 using AI:1 QEBSM:0 PCI:1 TDD:1 SIGA: W AOP
    <4> <0>Kernel panic - not syncing: Fatal exception in interrupt

Use tasklet_kill instead of tasklet_disbale. Since tasklet_schedule must not be
called after tasklet_kill use the QDIO_IRQ_STATE_STOPPED to inidicate that a
queue is going down and prevent further tasklet schedules in that case.

Remove superflous tasklet_schedule from input queue setup, at that time
the queues are not ready so the schedule results in a NOP.

Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26 15:24:20 +01:00
Jan Glauber
b454740246 [S390] qdio: add missing tiq_list locking
Add a mutex to protect the tiq_list. Although reading the list is done
using RCU adding and removing elements from the list must still
happen locked since multiple qdio devices may change the list in parallel
otherwise.

Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2009-03-26 15:24:19 +01:00
Jan Glauber
50f769df1c [S390] qdio: improve inbound buffer acknowledgement
- Use automatic acknowledgement of incoming buffers in QEBSM mode
- Move ACK for non-QEBSM mode always to the newest buffer to prevent
  a race with qdio_stop_polling
- Remove the polling spinlock, the upper layer drivers return new buffers
  in the same code path and could not run in parallel
- Don't flood the error log in case of no-target-buffer-empty
- In handle_inbound we check if we would overwrite an ACK'ed buffer, if so
  advance the pointer to the oldest ACK'ed buffer so we don't overwrite an
  empty buffer in qdio_stop_polling

Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-12-25 13:38:59 +01:00
Jan Glauber
22f9934767 [S390] qdio: rework debug feature logging
- make qdio_trace a per device view
- remove s390dbf exceptions
- remove CONFIG_QDIO_DEBUG, not needed anymore if we check for the level
  before calling sprintf
- use snprintf for dbf entries
- add start markers to see if the dbf view wrapped
- add a global error view for all queues

Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-12-25 13:38:59 +01:00
Jan Glauber
9a1ce28aeb [S390] qdio: fix compile warning under 31 bit
The QEBSM instructions are only available for CONFIG_64BIT, they are not
used under 31 bit. Make compiler happy about the false positive:

drivers/s390/cio/qdio_main.c: In function ?qdio_inbound_q_done?:
drivers/s390/cio/qdio_main.c:532: warning: ?state? may be used uninitialized in this function

Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-12-25 13:38:58 +01:00
Jan Glauber
53b41ba7ce [S390] qdio: prevent oopsing if qdio_establish fails
If qdio_establish fails we call qdio_shutdown to cleanup the
qdio subchannel. The tiq_list entry may not be valid at that
time, therefore we must ignore queues with an invalid list entry
in tiqdio_remove_input_queues.

Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
2008-08-21 19:46:39 +02:00
Jan Glauber
779e6e1c72 [S390] qdio: new qdio driver.
List of major changes:
- split qdio driver into several files
- seperation of thin interrupt code
- improved handling for multiple thin interrupt devices
- inbound and outbound processing now always runs in tasklet context
- significant less tasklet schedules per interrupt needed
- merged qebsm with non-qebsm handling
- cleanup qdio interface and added kerneldoc
- coding style

Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Utz Bacher <utz.bacher@de.ibm.com>
Reviewed-by: Ursula Braun <braunu@de.ibm.com>
Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2008-07-17 17:22:10 +02:00