]> www.infradead.org Git - users/jedix/linux-maple.git/commit
aacraid: Relinquish CPU during timeout wait
authorRaghava Aditya Renukunta <RaghavaAditya.Renukunta@microsemi.com>
Tue, 26 Apr 2016 06:31:26 +0000 (23:31 -0700)
committerChuck Anderson <chuck.anderson@oracle.com>
Mon, 27 Feb 2017 06:21:03 +0000 (22:21 -0800)
commit3bc644145243deca270ec57e79a7c95f8086bab7
tree2a036147cd3ae0f56169e78f2f63d562a990c6a3
parent45801aed4590eb421a1ca7fb65e4da619fbf555d
aacraid: Relinquish CPU during timeout wait

aac_fib_send has a special function case for initial commands during
driver initialization using wait < 0(pseudo sync mode). In this case,
the command does not sleep but rather spins checking for timeout.This
loop is calls cpu_relax() in an attempt to allow other processes/threads
to use the CPU, but this function does not relinquish the CPU and so the
command will hog the processor. This was observed in a KDUMP
"crashkernel" and that prevented the "command thread" (which is
responsible for completing the command from being timed out) from
starting because it could not get the CPU.

Fixed by replacing "cpu_relax()" call with "schedule()"
Cc: stable@vger.kernel.org
Signed-off-by: Raghava Aditya Renukunta <RaghavaAditya.Renukunta@microsemi.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Orabug: 25505509
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
(cherry picked from commit 07beca2be24cc710461c0b131832524c9ee08910)
Signed-off-by: Dhaval Giani <dhaval.giani@oracle.com>
drivers/scsi/aacraid/commsup.c