s390/pci_dma: make lazy flush independent from the tlb_refresh bit

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We have 2 strategies to reduce the number of RPCIT instructions:
* A HW feature indicated via the tlb_refresh bit allows us to omit RPCIT for
  invalid -> valid translation-table entry updates.
* With "lazy flush" we omit RPCIT for valid -> invalid updates until we run
  out of dma addresses. When we have to reuse dma addresses we issue a global
  tlb flush using only one RPCIT instruction.

Currently lazy flushing depends on tlb_refresh. Since there is no technical
reason for this remove this dependency.

Signed-off-by: Sebastian Ott <sebott@linux.vnet.ibm.com>
Reviewed-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

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Sebastian Ott 2016-09-08 13:44:57 +02:00 • committed by Martin Schwidefsky

parent 6b7df3ce92

commit 4f5359e94b

1 changed files with 11 additions and 8 deletions

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arch/s390/pci/pci_dma.c

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