From 3884f7b0a8382b89d8ca5da23bd98e3e15fc805b Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Tue, 27 Nov 2007 19:28:56 +0900 Subject: [PATCH] libata: clean up EH speed down implementation Clean up EH speed down implementation. * is_io boolean variable is replaced eflags. is_io is ATA_EFLAG_IS_IO. * Error categories now have names. * Better comments. * Reorder 5min and 10min rules in ata_eh_speed_down_verdict() * Use local variable @link to cache @dev->link in ata_eh_speed_down() These changes are to improve readability and ease further changes. This patch doesn't introduce any behavior change. Signed-off-by: Tejun Heo Signed-off-by: Jeff Garzik --- drivers/ata/libata-eh.c | 117 +++++++++++++++++++++++++--------------- include/linux/libata.h | 2 +- 2 files changed, 74 insertions(+), 45 deletions(-) diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c index ebab75958900..b01ade102727 100644 --- a/drivers/ata/libata-eh.c +++ b/drivers/ata/libata-eh.c @@ -46,9 +46,20 @@ #include "libata.h" enum { + /* speed down verdicts */ ATA_EH_SPDN_NCQ_OFF = (1 << 0), ATA_EH_SPDN_SPEED_DOWN = (1 << 1), ATA_EH_SPDN_FALLBACK_TO_PIO = (1 << 2), + + /* error flags */ + ATA_EFLAG_IS_IO = (1 << 0), + + /* error categories */ + ATA_ECAT_NONE = 0, + ATA_ECAT_ATA_BUS = 1, + ATA_ECAT_TOUT_HSM = 2, + ATA_ECAT_UNK_DEV = 3, + ATA_ECAT_NR = 4, }; /* Waiting in ->prereset can never be reliable. It's sometimes nice @@ -218,7 +229,7 @@ void ata_port_pbar_desc(struct ata_port *ap, int bar, ssize_t offset, #endif /* CONFIG_PCI */ -static void ata_ering_record(struct ata_ering *ering, int is_io, +static void ata_ering_record(struct ata_ering *ering, unsigned int eflags, unsigned int err_mask) { struct ata_ering_entry *ent; @@ -229,7 +240,7 @@ static void ata_ering_record(struct ata_ering *ering, int is_io, ering->cursor %= ATA_ERING_SIZE; ent = &ering->ring[ering->cursor]; - ent->is_io = is_io; + ent->eflags = eflags; ent->err_mask = err_mask; ent->timestamp = get_jiffies_64(); } @@ -1451,20 +1462,20 @@ static unsigned int ata_eh_analyze_tf(struct ata_queued_cmd *qc, return action; } -static int ata_eh_categorize_error(int is_io, unsigned int err_mask) +static int ata_eh_categorize_error(unsigned int eflags, unsigned int err_mask) { if (err_mask & AC_ERR_ATA_BUS) - return 1; + return ATA_ECAT_ATA_BUS; if (err_mask & AC_ERR_TIMEOUT) - return 2; + return ATA_ECAT_TOUT_HSM; - if (is_io) { + if (eflags & ATA_EFLAG_IS_IO) { if (err_mask & AC_ERR_HSM) - return 2; + return ATA_ECAT_TOUT_HSM; if ((err_mask & (AC_ERR_DEV|AC_ERR_MEDIA|AC_ERR_INVALID)) == AC_ERR_DEV) - return 3; + return ATA_ECAT_UNK_DEV; } return 0; @@ -1472,13 +1483,13 @@ static int ata_eh_categorize_error(int is_io, unsigned int err_mask) struct speed_down_verdict_arg { u64 since; - int nr_errors[4]; + int nr_errors[ATA_ECAT_NR]; }; static int speed_down_verdict_cb(struct ata_ering_entry *ent, void *void_arg) { struct speed_down_verdict_arg *arg = void_arg; - int cat = ata_eh_categorize_error(ent->is_io, ent->err_mask); + int cat = ata_eh_categorize_error(ent->eflags, ent->err_mask); if (ent->timestamp < arg->since) return -1; @@ -1495,22 +1506,33 @@ static int speed_down_verdict_cb(struct ata_ering_entry *ent, void *void_arg) * whether NCQ needs to be turned off, transfer speed should be * stepped down, or falling back to PIO is necessary. * - * Cat-1 is ATA_BUS error for any command. + * ECAT_ATA_BUS : ATA_BUS error for any command + * + * ECAT_TOUT_HSM : TIMEOUT for any command or HSM violation for + * IO commands + * + * ECAT_UNK_DEV : Unknown DEV error for IO commands + * + * Verdicts are * - * Cat-2 is TIMEOUT for any command or HSM violation for known - * supported commands. + * NCQ_OFF : Turn off NCQ. * - * Cat-3 is is unclassified DEV error for known supported - * command. + * SPEED_DOWN : Speed down transfer speed but don't fall back + * to PIO. * - * NCQ needs to be turned off if there have been more than 3 - * Cat-2 + Cat-3 errors during last 10 minutes. + * FALLBACK_TO_PIO : Fall back to PIO. * - * Speed down is necessary if there have been more than 3 Cat-1 + - * Cat-2 errors or 10 Cat-3 errors during last 10 minutes. + * Even if multiple verdicts are returned, only one action is + * taken per error. ering is cleared after an action is taken. * - * Falling back to PIO mode is necessary if there have been more - * than 10 Cat-1 + Cat-2 + Cat-3 errors during last 5 minutes. + * 1. If more than 10 ATA_BUS, TOUT_HSM or UNK_DEV errors + * ocurred during last 5 mins, FALLBACK_TO_PIO + * + * 2. If more than 3 TOUT_HSM or UNK_DEV errors occurred + * during last 10 mins, NCQ_OFF. + * + * 3. If more than 3 ATA_BUS or TOUT_HSM errors, or more than 10 + * UNK_DEV errors occurred during last 10 mins, SPEED_DOWN. * * LOCKING: * Inherited from caller. @@ -1525,23 +1547,29 @@ static unsigned int ata_eh_speed_down_verdict(struct ata_device *dev) struct speed_down_verdict_arg arg; unsigned int verdict = 0; - /* scan past 10 mins of error history */ + /* scan past 5 mins of error history */ memset(&arg, 0, sizeof(arg)); - arg.since = j64 - min(j64, j10mins); + arg.since = j64 - min(j64, j5mins); ata_ering_map(&dev->ering, speed_down_verdict_cb, &arg); - if (arg.nr_errors[2] + arg.nr_errors[3] > 3) - verdict |= ATA_EH_SPDN_NCQ_OFF; - if (arg.nr_errors[1] + arg.nr_errors[2] > 3 || arg.nr_errors[3] > 10) - verdict |= ATA_EH_SPDN_SPEED_DOWN; + if (arg.nr_errors[ATA_ECAT_ATA_BUS] + + arg.nr_errors[ATA_ECAT_TOUT_HSM] + + arg.nr_errors[ATA_ECAT_UNK_DEV] > 10) + verdict |= ATA_EH_SPDN_FALLBACK_TO_PIO; - /* scan past 3 mins of error history */ + /* scan past 10 mins of error history */ memset(&arg, 0, sizeof(arg)); - arg.since = j64 - min(j64, j5mins); + arg.since = j64 - min(j64, j10mins); ata_ering_map(&dev->ering, speed_down_verdict_cb, &arg); - if (arg.nr_errors[1] + arg.nr_errors[2] + arg.nr_errors[3] > 10) - verdict |= ATA_EH_SPDN_FALLBACK_TO_PIO; + if (arg.nr_errors[ATA_ECAT_TOUT_HSM] + + arg.nr_errors[ATA_ECAT_UNK_DEV] > 3) + verdict |= ATA_EH_SPDN_NCQ_OFF; + + if (arg.nr_errors[ATA_ECAT_ATA_BUS] + + arg.nr_errors[ATA_ECAT_TOUT_HSM] > 3 || + arg.nr_errors[ATA_ECAT_UNK_DEV] > 10) + verdict |= ATA_EH_SPDN_SPEED_DOWN; return verdict; } @@ -1549,7 +1577,7 @@ static unsigned int ata_eh_speed_down_verdict(struct ata_device *dev) /** * ata_eh_speed_down - record error and speed down if necessary * @dev: Failed device - * @is_io: Did the device fail during normal IO? + * @eflags: mask of ATA_EFLAG_* flags * @err_mask: err_mask of the error * * Record error and examine error history to determine whether @@ -1563,18 +1591,19 @@ static unsigned int ata_eh_speed_down_verdict(struct ata_device *dev) * RETURNS: * Determined recovery action. */ -static unsigned int ata_eh_speed_down(struct ata_device *dev, int is_io, - unsigned int err_mask) +static unsigned int ata_eh_speed_down(struct ata_device *dev, + unsigned int eflags, unsigned int err_mask) { + struct ata_link *link = dev->link; unsigned int verdict; unsigned int action = 0; /* don't bother if Cat-0 error */ - if (ata_eh_categorize_error(is_io, err_mask) == 0) + if (ata_eh_categorize_error(eflags, err_mask) == 0) return 0; /* record error and determine whether speed down is necessary */ - ata_ering_record(&dev->ering, is_io, err_mask); + ata_ering_record(&dev->ering, eflags, err_mask); verdict = ata_eh_speed_down_verdict(dev); /* turn off NCQ? */ @@ -1590,7 +1619,7 @@ static unsigned int ata_eh_speed_down(struct ata_device *dev, int is_io, /* speed down? */ if (verdict & ATA_EH_SPDN_SPEED_DOWN) { /* speed down SATA link speed if possible */ - if (sata_down_spd_limit(dev->link) == 0) { + if (sata_down_spd_limit(link) == 0) { action |= ATA_EH_HARDRESET; goto done; } @@ -1621,7 +1650,7 @@ static unsigned int ata_eh_speed_down(struct ata_device *dev, int is_io, * SATA. Consider it only for PATA. */ if ((verdict & ATA_EH_SPDN_FALLBACK_TO_PIO) && (dev->spdn_cnt >= 2) && - (dev->link->ap->cbl != ATA_CBL_SATA) && + (link->ap->cbl != ATA_CBL_SATA) && (dev->xfer_shift != ATA_SHIFT_PIO)) { if (ata_down_xfermask_limit(dev, ATA_DNXFER_FORCE_PIO) == 0) { dev->spdn_cnt = 0; @@ -1653,8 +1682,8 @@ static void ata_eh_link_autopsy(struct ata_link *link) struct ata_port *ap = link->ap; struct ata_eh_context *ehc = &link->eh_context; struct ata_device *dev; - unsigned int all_err_mask = 0; - int tag, is_io = 0; + unsigned int all_err_mask = 0, eflags = 0; + int tag; u32 serror; int rc; @@ -1713,15 +1742,15 @@ static void ata_eh_link_autopsy(struct ata_link *link) ehc->i.dev = qc->dev; all_err_mask |= qc->err_mask; if (qc->flags & ATA_QCFLAG_IO) - is_io = 1; + eflags |= ATA_EFLAG_IS_IO; } /* enforce default EH actions */ if (ap->pflags & ATA_PFLAG_FROZEN || all_err_mask & (AC_ERR_HSM | AC_ERR_TIMEOUT)) ehc->i.action |= ATA_EH_SOFTRESET; - else if ((is_io && all_err_mask) || - (!is_io && (all_err_mask & ~AC_ERR_DEV))) + else if (((eflags & ATA_EFLAG_IS_IO) && all_err_mask) || + (!(eflags & ATA_EFLAG_IS_IO) && (all_err_mask & ~AC_ERR_DEV))) ehc->i.action |= ATA_EH_REVALIDATE; /* If we have offending qcs and the associated failed device, @@ -1744,7 +1773,7 @@ static void ata_eh_link_autopsy(struct ata_link *link) dev = link->device; if (dev) - ehc->i.action |= ata_eh_speed_down(dev, is_io, all_err_mask); + ehc->i.action |= ata_eh_speed_down(dev, eflags, all_err_mask); DPRINTK("EXIT\n"); } diff --git a/include/linux/libata.h b/include/linux/libata.h index ca347b018649..74f1255e2524 100644 --- a/include/linux/libata.h +++ b/include/linux/libata.h @@ -482,7 +482,7 @@ struct ata_port_stats { }; struct ata_ering_entry { - int is_io; + unsigned int eflags; unsigned int err_mask; u64 timestamp; }; -- 2.20.1