MTD: fix possible starvation in cfi_cmdset_0001.c

Thomas Gall
2005-12-02T21:00:33Z

The patch below fixes a potential starvation issue that can arise when
there is contention on a chip during a period when a process is
currently writing to it. The starvation is avoided by conditionally
rescheduling when the chip is left in a state usable by other processes.

Please CC Josh and myself and replies. Thanks!

Signed-off-by: Josh Boyer <jdub@us.ibm.com>
Signed-off-by: Tom Gall <tom_gall@vnet.ibm.com>

drivers/mtd/chips/cfi_cmdset_0001.c | 5 +++++
1 files changed, 5 insertions(+)

Index: mtd/drivers/mtd/chips/cfi_cmdset_0001.c
===================================================================
--- mtd.orig/drivers/mtd/chips/cfi_cmdset_0001.c 2005-11-07 15:04:33.000000000 -0600
+++ mtd/drivers/mtd/chips/cfi_cmdset_0001.c 2005-11-08 08:54:54.000000000 -0600
@@ -1695,6 +1695,11 @@ static int cfi_intelext_writev (struct m
if (chipnum == cfi->numchips)
return 0;
}
+
+ /* Be nice and reschedule with the chip in a usable state for other
+ processes. */
+ cond_resched();
+
} while (len);

return 0;

--
Linux Technology Center
Senior Software Engineer, - Embedded Linux
w) tom_gall@vnet.ibm.com 553-4558
h) tgall@uberh4x0r.org
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