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author | Michael J. Ruhl <michael.j.ruhl@intel.com> | 2017-05-04 05:15:15 -0700 |
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committer | Doug Ledford <dledford@redhat.com> | 2017-05-04 19:31:46 -0400 |
commit | 8737ce95c463c6d8c4307ab3d6858cbf71cd4fc8 (patch) | |
tree | 1afce2cd49297cb1211ebc09f4131806dc036eb3 /drivers/infiniband/hw/hfi1/intr.c | |
parent | 9b60d2cbe07486658a32d4ed2fff7085c44bae7a (diff) | |
download | linux-stable-8737ce95c463c6d8c4307ab3d6858cbf71cd4fc8.tar.gz linux-stable-8737ce95c463c6d8c4307ab3d6858cbf71cd4fc8.tar.bz2 linux-stable-8737ce95c463c6d8c4307ab3d6858cbf71cd4fc8.zip |
IB/hfi1: Fix an assign/ordering issue with shared context IDs
The current algorithm for generating sub-context IDs is FILO. If the
contexts are not closed in that order, the uniqueness of the ID will be
compromised. I.e. logging the creation/deletion of context IDs with an
application that assigns and closes in a FIFO order reveals:
cache_id: assign: uctxt: 3 sub_ctxt: 0
cache_id: assign: uctxt: 3 sub_ctxt: 1
cache_id: assign: uctxt: 3 sub_ctxt: 2
cache_id: close: uctxt: 3 sub_ctxt: 0
cache_id: assign: uctxt: 3 sub_ctxt: 2 <<<
The sub_ctxt ID 2 is reused incorrectly.
Update the sub-context ID assign algorithm to use a bitmask of in_use
contexts. The new algorithm will allow the contexts to be closed in any
order, and will only re-use unused contexts.
Size subctxt and subctxt_cnt to match the user API size.
Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Michael J. Ruhl <michael.j.ruhl@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
Diffstat (limited to 'drivers/infiniband/hw/hfi1/intr.c')
-rw-r--r-- | drivers/infiniband/hw/hfi1/intr.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/infiniband/hw/hfi1/intr.c b/drivers/infiniband/hw/hfi1/intr.c index 232014d46f79..ba265d0ae93b 100644 --- a/drivers/infiniband/hw/hfi1/intr.c +++ b/drivers/infiniband/hw/hfi1/intr.c @@ -47,6 +47,7 @@ #include <linux/pci.h> #include <linux/delay.h> +#include <linux/bitmap.h> #include "hfi.h" #include "common.h" @@ -189,7 +190,7 @@ void handle_user_interrupt(struct hfi1_ctxtdata *rcd) unsigned long flags; spin_lock_irqsave(&dd->uctxt_lock, flags); - if (!rcd->cnt) + if (bitmap_empty(rcd->in_use_ctxts, HFI1_MAX_SHARED_CTXTS)) goto done; if (test_and_clear_bit(HFI1_CTXT_WAITING_RCV, &rcd->event_flags)) { |