On 12/15/2017 01:18 PM, Hannes Reinecke wrote: > On 12/08/2017 10:42 AM, Jason Yan wrote: >> If the PHY burst too many events, we will alloc a lot of events for the >> worker. This may leads to memory exhaustion. >> >> Dan Williams suggested to shut down the PHY if the events reached the >> threshold, because in this case the PHY may have gone into some >> erroneous state. Users can re-enable the PHY by sysfs if they want. >> >> We cannot use the fixed memory pool because if we run out of events, the >> shut down event and loss of signal event will lost too. The events still >> need to be allocated and processed in this case. >> >> Suggested-by: Dan Williams <[email protected]> >> Signed-off-by: Jason Yan <[email protected]> >> CC: John Garry <[email protected]> >> CC: Johannes Thumshirn <[email protected]> >> CC: Ewan Milne <[email protected]> >> CC: Christoph Hellwig <[email protected]> >> CC: Tomas Henzl <[email protected]> >> --- >> drivers/scsi/libsas/sas_init.c | 33 ++++++++++++++++++++++++++++++++- >> drivers/scsi/libsas/sas_phy.c | 27 ++++++++++++++++++++++++++- >> include/scsi/libsas.h | 6 ++++++ >> 3 files changed, 64 insertions(+), 2 deletions(-) >> > Well, this still looks a bit error prone; what if the system runs out of > memory before the pool is exhausted? > (Also a threshold of 1024 events is a bit arbitrary; one might want to > adjust that). > > Couldn't you allocate two static events always (for shutdown and signal > loss), and then use a fixed pool? > Has actually been resolved by the next patch.
Reviewed-by: Hannes Reinecke <[email protected]> Cheers, Hannes -- Dr. Hannes Reinecke Teamlead Storage & Networking [email protected] +49 911 74053 688 SUSE LINUX GmbH, Maxfeldstr. 5, 90409 Nürnberg GF: F. Imendörffer, J. Smithard, J. Guild, D. Upmanyu, G. Norton HRB 21284 (AG Nürnberg)
