From de1b04388f63cbddf91d9f6c50c29be7232881ca Mon Sep 17 00:00:00 2001 From: Peter Oberparleiter Date: Mon, 7 Dec 2009 12:51:40 +0100 Subject: [PATCH] [S390] cio: improve error recovery for internal I/Os Improve error recovery for internal I/Os by repeating each I/O 256 times per path to cope with long-running non-permanent error conditions. Also retry each path twice to cope with link flapping, i.e. single paths becoming unavailable in the order in which they are tried. Signed-off-by: Peter Oberparleiter Signed-off-by: Martin Schwidefsky --- drivers/s390/cio/ccwreq.c | 7 ++++--- drivers/s390/cio/device_id.c | 2 +- drivers/s390/cio/device_pgid.c | 2 +- drivers/s390/cio/io_sch.h | 2 +- 4 files changed, 7 insertions(+), 6 deletions(-) diff --git a/drivers/s390/cio/ccwreq.c b/drivers/s390/cio/ccwreq.c index a6e205a384b2..9509e3860934 100644 --- a/drivers/s390/cio/ccwreq.c +++ b/drivers/s390/cio/ccwreq.c @@ -82,7 +82,7 @@ static void ccwreq_do(struct ccw_device *cdev) /* Perform start function. */ sch->lpm = 0xff; memset(&cdev->private->irb, 0, sizeof(struct irb)); - rc = cio_start(sch, cp, req->mask); + rc = cio_start(sch, cp, (u8) req->mask); if (rc == 0) { /* I/O started successfully. */ ccw_device_set_timeout(cdev, req->timeout); @@ -116,7 +116,8 @@ void ccw_request_start(struct ccw_device *cdev) { struct ccw_request *req = &cdev->private->req; - req->mask = 0x80; + /* Try all paths twice to counter link flapping. */ + req->mask = 0x8080; req->retries = req->maxretries; req->mask = lpm_adjust(req->mask, req->lpm); req->drc = 0; @@ -212,7 +213,7 @@ static void ccwreq_log_status(struct ccw_device *cdev, enum io_status status) } __attribute__ ((packed)) data; data.dev_id = cdev->private->dev_id; data.retries = req->retries; - data.lpm = req->mask; + data.lpm = (u8) req->mask; data.status = (u8) status; CIO_TRACE_EVENT(2, "reqstat"); CIO_HEX_EVENT(2, &data, sizeof(data)); diff --git a/drivers/s390/cio/device_id.c b/drivers/s390/cio/device_id.c index 4728644ed85c..78a0b43862c5 100644 --- a/drivers/s390/cio/device_id.c +++ b/drivers/s390/cio/device_id.c @@ -21,7 +21,7 @@ #include "device.h" #include "io_sch.h" -#define SENSE_ID_RETRIES 5 +#define SENSE_ID_RETRIES 256 #define SENSE_ID_TIMEOUT (10 * HZ) #define SENSE_ID_MIN_LEN 4 #define SENSE_ID_BASIC_LEN 7 diff --git a/drivers/s390/cio/device_pgid.c b/drivers/s390/cio/device_pgid.c index 5bcefeaff744..aad188e43b4f 100644 --- a/drivers/s390/cio/device_pgid.c +++ b/drivers/s390/cio/device_pgid.c @@ -20,7 +20,7 @@ #include "device.h" #include "io_sch.h" -#define PGID_RETRIES 5 +#define PGID_RETRIES 256 #define PGID_TIMEOUT (10 * HZ) /* diff --git a/drivers/s390/cio/io_sch.h b/drivers/s390/cio/io_sch.h index dbc69a5a043e..d72ae4c93af9 100644 --- a/drivers/s390/cio/io_sch.h +++ b/drivers/s390/cio/io_sch.h @@ -109,7 +109,7 @@ struct ccw_request { void (*callback)(struct ccw_device *, void *, int); void *data; /* These fields are used internally. */ - u8 mask; + u16 mask; u16 retries; int drc; int cancel:1;