From aa0fec62391cd429385e7f3f9fc4a1fb8e2d1218 Mon Sep 17 00:00:00 2001 From: Christof Schmitt Date: Mon, 19 May 2008 12:17:47 +0200 Subject: [PATCH] [SCSI] zfcp: Fix sparse warning by providing new entry in dbf drivers/s390/scsi/zfcp_dbf.c:692:2: warning: context imbalance in 'zfcp_rec_dbf_event_thread' - different lock contexts for basic block Replace the parameter indicating if the lock is held with a new entry function that only acquires the lock. This makes the lock handling more visible and removes the sparse warning. Signed-off-by: Christof Schmitt Signed-off-by: Martin Peschke Signed-off-by: James Bottomley --- drivers/s390/scsi/zfcp_dbf.c | 23 +++++++++++++++++------ drivers/s390/scsi/zfcp_erp.c | 18 +++++++++--------- drivers/s390/scsi/zfcp_ext.h | 4 ++-- 3 files changed, 28 insertions(+), 17 deletions(-) diff --git a/drivers/s390/scsi/zfcp_dbf.c b/drivers/s390/scsi/zfcp_dbf.c index e908c0631ace..558dae9639f3 100644 --- a/drivers/s390/scsi/zfcp_dbf.c +++ b/drivers/s390/scsi/zfcp_dbf.c @@ -670,24 +670,20 @@ static struct debug_view zfcp_rec_dbf_view = { * zfcp_rec_dbf_event_thread - trace event related to recovery thread operation * @id2: identifier for event * @adapter: adapter - * @lock: non-zero value indicates that erp_lock has not yet been acquired + * This function assumes that the caller is holding erp_lock. */ -void zfcp_rec_dbf_event_thread(u8 id2, struct zfcp_adapter *adapter, int lock) +void zfcp_rec_dbf_event_thread(u8 id2, struct zfcp_adapter *adapter) { struct zfcp_rec_dbf_record *r = &adapter->rec_dbf_buf; unsigned long flags = 0; struct list_head *entry; unsigned ready = 0, running = 0, total; - if (lock) - read_lock_irqsave(&adapter->erp_lock, flags); list_for_each(entry, &adapter->erp_ready_head) ready++; list_for_each(entry, &adapter->erp_running_head) running++; total = adapter->erp_total_count; - if (lock) - read_unlock_irqrestore(&adapter->erp_lock, flags); spin_lock_irqsave(&adapter->rec_dbf_lock, flags); memset(r, 0, sizeof(*r)); @@ -700,6 +696,21 @@ void zfcp_rec_dbf_event_thread(u8 id2, struct zfcp_adapter *adapter, int lock) spin_unlock_irqrestore(&adapter->rec_dbf_lock, flags); } +/** + * zfcp_rec_dbf_event_thread - trace event related to recovery thread operation + * @id2: identifier for event + * @adapter: adapter + * This function assumes that the caller does not hold erp_lock. + */ +void zfcp_rec_dbf_event_thread_lock(u8 id2, struct zfcp_adapter *adapter) +{ + unsigned long flags; + + read_lock_irqsave(&adapter->erp_lock, flags); + zfcp_rec_dbf_event_thread(id2, adapter); + read_unlock_irqrestore(&adapter->erp_lock, flags); +} + static void zfcp_rec_dbf_event_target(u8 id2, void *ref, struct zfcp_adapter *adapter, atomic_t *status, atomic_t *erp_count, diff --git a/drivers/s390/scsi/zfcp_erp.c b/drivers/s390/scsi/zfcp_erp.c index 55a4fdc42626..d05b37054897 100644 --- a/drivers/s390/scsi/zfcp_erp.c +++ b/drivers/s390/scsi/zfcp_erp.c @@ -783,7 +783,7 @@ zfcp_erp_action_ready(struct zfcp_erp_action *erp_action) zfcp_erp_action_to_ready(erp_action); up(&adapter->erp_ready_sem); - zfcp_rec_dbf_event_thread(2, adapter, 0); + zfcp_rec_dbf_event_thread(2, adapter); } /* @@ -995,7 +995,7 @@ zfcp_erp_thread_kill(struct zfcp_adapter *adapter) atomic_set_mask(ZFCP_STATUS_ADAPTER_ERP_THREAD_KILL, &adapter->status); up(&adapter->erp_ready_sem); - zfcp_rec_dbf_event_thread(2, adapter, 1); + zfcp_rec_dbf_event_thread_lock(2, adapter); wait_event(adapter->erp_thread_wqh, !atomic_test_mask(ZFCP_STATUS_ADAPTER_ERP_THREAD_UP, @@ -1050,9 +1050,9 @@ zfcp_erp_thread(void *data) * no action in 'ready' queue to be processed and * thread is not to be killed */ - zfcp_rec_dbf_event_thread(4, adapter, 1); + zfcp_rec_dbf_event_thread_lock(4, adapter); down_interruptible(&adapter->erp_ready_sem); - zfcp_rec_dbf_event_thread(5, adapter, 1); + zfcp_rec_dbf_event_thread_lock(5, adapter); } atomic_clear_mask(ZFCP_STATUS_ADAPTER_ERP_THREAD_UP, &adapter->status); @@ -2062,9 +2062,9 @@ zfcp_erp_adapter_strategy_open_fsf_xconfig(struct zfcp_erp_action *erp_action) * _must_ be the one belonging to the 'exchange config * data' request. */ - zfcp_rec_dbf_event_thread(6, adapter, 1); + zfcp_rec_dbf_event_thread_lock(6, adapter); down(&adapter->erp_ready_sem); - zfcp_rec_dbf_event_thread(7, adapter, 1); + zfcp_rec_dbf_event_thread_lock(7, adapter); if (erp_action->status & ZFCP_STATUS_ERP_TIMEDOUT) { ZFCP_LOG_INFO("error: exchange of configuration data " "for adapter %s timed out\n", @@ -2118,9 +2118,9 @@ zfcp_erp_adapter_strategy_open_fsf_xport(struct zfcp_erp_action *erp_action) } ret = ZFCP_ERP_SUCCEEDED; - zfcp_rec_dbf_event_thread(8, adapter, 1); + zfcp_rec_dbf_event_thread_lock(8, adapter); down(&adapter->erp_ready_sem); - zfcp_rec_dbf_event_thread(9, adapter, 1); + zfcp_rec_dbf_event_thread_lock(9, adapter); if (erp_action->status & ZFCP_STATUS_ERP_TIMEDOUT) { ZFCP_LOG_INFO("error: exchange port data timed out (adapter " "%s)\n", zfcp_get_busid_by_adapter(adapter)); @@ -2876,7 +2876,7 @@ static int zfcp_erp_action_enqueue(int want, struct zfcp_adapter *adapter, /* finally put it into 'ready' queue and kick erp thread */ list_add_tail(&erp_action->list, &adapter->erp_ready_head); up(&adapter->erp_ready_sem); - zfcp_rec_dbf_event_thread(1, adapter, 0); + zfcp_rec_dbf_event_thread(1, adapter); retval = 0; out: zfcp_rec_dbf_event_trigger(id, ref, want, need, erp_action, diff --git a/drivers/s390/scsi/zfcp_ext.h b/drivers/s390/scsi/zfcp_ext.h index 16213cbbc4ba..e47ab8d05b67 100644 --- a/drivers/s390/scsi/zfcp_ext.h +++ b/drivers/s390/scsi/zfcp_ext.h @@ -169,8 +169,8 @@ extern void zfcp_erp_port_access_changed(struct zfcp_port *, u8, void *); extern void zfcp_erp_unit_access_changed(struct zfcp_unit *, u8, void *); /******************************** AUX ****************************************/ -extern void zfcp_rec_dbf_event_thread(u8 id, struct zfcp_adapter *adapter, - int lock); +extern void zfcp_rec_dbf_event_thread(u8 id, struct zfcp_adapter *adapter); +extern void zfcp_rec_dbf_event_thread_lock(u8 id, struct zfcp_adapter *adapter); extern void zfcp_rec_dbf_event_adapter(u8 id, void *ref, struct zfcp_adapter *); extern void zfcp_rec_dbf_event_port(u8 id, void *ref, struct zfcp_port *port); extern void zfcp_rec_dbf_event_unit(u8 id, void *ref, struct zfcp_unit *unit); -- GitLab