diff options
| author | Haren Myneni <haren@linux.ibm.com> | 2020-04-16 09:04:19 +0300 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2020-04-20 09:53:00 +0300 |
| commit | 461862ef94a88e4b74e177b82bee2c81c6535fae (patch) | |
| tree | 1c97c992a121f58b382c26e23db4100aa6009bca /arch/powerpc/platforms/powernv/vas-fault.c | |
| parent | c96c4436aba4c12f1f48369f2f90bc43e12fe36c (diff) | |
| download | linux-461862ef94a88e4b74e177b82bee2c81c6535fae.tar.xz | |
powerpc/vas: Return credits after handling fault
NX uses credit mechanism to control the number of requests issued on
a specific window at any point of time. Only send windows and fault
window are used credits. When the request is issued on a given window,
a credit is taken. This credit will be returned after that request is
processed. If credits are not available, returns RMA_Busy for send
window and RMA_Reject for fault window.
NX expects OS to return credit for send window after processing fault
CRB. Also credit has to be returned for fault window after handling
the fault.
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Signed-off-by: Haren Myneni <haren@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1587017059.2275.1064.camel@hbabu-laptop
Diffstat (limited to 'arch/powerpc/platforms/powernv/vas-fault.c')
| -rw-r--r-- | arch/powerpc/platforms/powernv/vas-fault.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/arch/powerpc/platforms/powernv/vas-fault.c b/arch/powerpc/platforms/powernv/vas-fault.c index 354577dcf2dc..b6bec64d793e 100644 --- a/arch/powerpc/platforms/powernv/vas-fault.c +++ b/arch/powerpc/platforms/powernv/vas-fault.c @@ -224,6 +224,10 @@ irqreturn_t vas_fault_thread_fn(int irq, void *data) memcpy(crb, fifo, CRB_SIZE); entry->stamp.nx.pswid = cpu_to_be32(FIFO_INVALID_ENTRY); entry->ccw |= cpu_to_be32(CCW0_INVALID); + /* + * Return credit for the fault window. + */ + vas_return_credit(vinst->fault_win, false); pr_devel("VAS[%d] fault_fifo %p, fifo %p, fault_crbs %d\n", vinst->vas_id, vinst->fault_fifo, fifo, @@ -249,6 +253,11 @@ irqreturn_t vas_fault_thread_fn(int irq, void *data) WARN_ON_ONCE(1); } else { update_csb(window, crb); + /* + * Return credit for send window after processing + * fault CRB. + */ + vas_return_credit(window, true); } } } |