mirror of
https://github.com/freebsd/freebsd-src
synced 2024-10-18 06:14:27 +00:00
cb32189e23
out of cdregister() and daregister(), which are run from interrupt context. The sysctl code does blocking mallocs (M_WAITOK), which causes problems if malloc(9) actually needs to sleep. The eventual fix for this issue will involve moving the CAM probe process inside a kernel thread. For now, though, I have fixed the issue by moving dynamic sysctl variable creation for these two drivers to a task queue running in a kernel thread. The existing task queues (taskqueue_swi and taskqueue_swi_giant) run in software interrupt handlers, which wouldn't fix the problem at hand. So I have created a new task queue, taskqueue_thread, that runs inside a kernel thread. (It also runs outside of Giant -- clients must explicitly acquire and release Giant in their taskqueue functions.) scsi_cd.c: Remove sysctl variable creation code from cdregister(), and move it to a new function, cdsysctlinit(). Queue cdsysctlinit() to the taskqueue_thread taskqueue once we have fully registered the cd(4) driver instance. scsi_da.c: Remove sysctl variable creation code from daregister(), and move it to move it to a new function, dasysctlinit(). Queue dasysctlinit() to the taskqueue_thread taskqueue once we have fully registered the da(4) instance. taskqueue.h: Declare the new taskqueue_thread taskqueue, update some comments. subr_taskqueue.c: Create the new kernel thread taskqueue. This taskqueue runs outside of Giant, so any functions queued to it would need to explicitly acquire/release Giant if they need it. cd.4: Update the cd(4) man page to talk about the minimum command size sysctl/loader tunable. Also note that the changer variables are available as loader tunables as well. da.4: Update the da(4) man page to cover the retry_count, default_timeout and minimum_cmd_size sysctl variables/loader tunables. Remove references to /dev/r???, they aren't used any longer. cd.9: Update the cd(9) man page to describe the CD_Q_10_BYTE_ONLY quirk. taskqueue.9: Update the taskqueue(9) man page to describe the new thread task queue, and the taskqueue_swi_giant queue. MFC after: 3 days |
||
|---|---|---|
| .. | ||
| scsi_all.c | ||
| scsi_all.h | ||
| scsi_cd.c | ||
| scsi_cd.h | ||
| scsi_ch.c | ||
| scsi_ch.h | ||
| scsi_da.c | ||
| scsi_da.h | ||
| scsi_dvcfg.h | ||
| scsi_iu.h | ||
| scsi_low.c | ||
| scsi_low.h | ||
| scsi_low_pisa.c | ||
| scsi_low_pisa.h | ||
| scsi_message.h | ||
| scsi_pass.c | ||
| scsi_pass.h | ||
| scsi_pt.c | ||
| scsi_pt.h | ||
| scsi_sa.c | ||
| scsi_sa.h | ||
| scsi_ses.c | ||
| scsi_ses.h | ||
| scsi_targ_bh.c | ||
| scsi_target.c | ||
| scsi_targetio.h | ||