svn commit: r212465 - head/sys/cddl/contrib/opensolaris/uts/common/dtrace

[Rui Paulo]

On 11 Sep 2010, at 14:23, Kostik Belousov wrote:

> On Sat, Sep 11, 2010 at 12:58:31PM +0000, Rui Paulo wrote:
>> Author: rpaulo
>> Date: Sat Sep 11 12:58:31 2010
>> New Revision: 212465
>> URL: http://svn.freebsd.org/changeset/base/212465
>> 
>> Log:
>>  Avoid a LOR (sleepable after non-sleepable) in
>>  fasttrap_tracepoint_enable().
>> 
>>  Sponsored by:	The FreeBSD Foundation
>> 
>> Modified:
>>  head/sys/cddl/contrib/opensolaris/uts/common/dtrace/fasttrap.c
>> 
>> Modified: head/sys/cddl/contrib/opensolaris/uts/common/dtrace/fasttrap.c
>> ==============================================================================
>> --- head/sys/cddl/contrib/opensolaris/uts/common/dtrace/fasttrap.c	Sat Sep 11 12:51:01 2010	(r212464)
>> +++ head/sys/cddl/contrib/opensolaris/uts/common/dtrace/fasttrap.c	Sat Sep 11 12:58:31 2010	(r212465)
>> @@ -591,7 +591,9 @@ fasttrap_tracepoint_enable(proc_t *p, fa
>> 	 * Before we make any modifications, make sure we've imposed a barrier
>> 	 * on the generation in which this probe was last modified.
>> 	 */
>> +	PROC_UNLOCK(p);
>> 	fasttrap_mod_barrier(probe->ftp_gen);
>> +	PROC_LOCK(p);
>> 
>> 	bucket = &fasttrap_tpoints.fth_table[FASTTRAP_TPOINTS_INDEX(pid, pc)];
>> 
> I suspect that you should hold the process around unlocked region.

The unlocked region in the diff ? You're saying I shouldn't unlock/lock here?

> fasttrap_pid_enable() also does unlock, so it might be better to hold
> the process immediately after pfind().

You mean use _PHOLD after pfind()?

Regards,
--
Rui Paulo