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authorGrzegorz Morys <grzegorz.morys@intel.com>2017-10-09 12:38:04 -0700
committerDoug Ledford <dledford@redhat.com>2017-10-18 10:12:59 -0400
commitb65c2045cc5089bd3cfacc9fad63798fded64226 (patch)
treeca0731936e74205d458e460fc38fcbdc854a16fd /drivers/infiniband/hw/hfi1
parent621515da67f150eea0e7b6b05614bd0b65d9d16c (diff)
downloadlinux-b65c2045cc5089bd3cfacc9fad63798fded64226.tar.bz2
IB/hfi1: Correct unnecessary acquisition of HW mutex
Avoid acquiring already acquired hardware mutex and releasing the unacquired one as these are redundant operations. Add printouts for such situations to help detect potential errors within the driver. Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com> Signed-off-by: Grzegorz Morys <grzegorz.morys@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')
-rw-r--r--drivers/infiniband/hw/hfi1/firmware.c19
1 files changed, 17 insertions, 2 deletions
diff --git a/drivers/infiniband/hw/hfi1/firmware.c b/drivers/infiniband/hw/hfi1/firmware.c
index 001698b744ee..cea0d4f3248f 100644
--- a/drivers/infiniband/hw/hfi1/firmware.c
+++ b/drivers/infiniband/hw/hfi1/firmware.c
@@ -1387,7 +1387,14 @@ int acquire_hw_mutex(struct hfi1_devdata *dd)
unsigned long timeout;
int try = 0;
u8 mask = 1 << dd->hfi1_id;
- u8 user;
+ u8 user = (u8)read_csr(dd, ASIC_CFG_MUTEX);
+
+ if (user == mask) {
+ dd_dev_info(dd,
+ "Hardware mutex already acquired, mutex mask %u\n",
+ (u32)mask);
+ return 0;
+ }
retry:
timeout = msecs_to_jiffies(HM_TIMEOUT) + jiffies;
@@ -1418,7 +1425,15 @@ retry:
void release_hw_mutex(struct hfi1_devdata *dd)
{
- write_csr(dd, ASIC_CFG_MUTEX, 0);
+ u8 mask = 1 << dd->hfi1_id;
+ u8 user = (u8)read_csr(dd, ASIC_CFG_MUTEX);
+
+ if (user != mask)
+ dd_dev_warn(dd,
+ "Unable to release hardware mutex, mutex mask %u, my mask %u\n",
+ (u32)user, (u32)mask);
+ else
+ write_csr(dd, ASIC_CFG_MUTEX, 0);
}
/* return the given resource bit(s) as a mask for the given HFI */