From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Nicholas A. Bellinger" Subject: [PATCH] qla2xxx: Don't memset buffer unless debug level is enabled Date: Wed, 30 Nov 2011 22:03:59 +0000 Message-ID: <1322690639-20756-1-git-send-email-nab@linux-iscsi.org> Return-path: Sender: target-devel-owner@vger.kernel.org To: linux-scsi Cc: target-devel , Nicholas Bellinger , Andrew Vasquez , Giridhar Malavali , Roland Dreier , Joern Engel , James Bottomley List-Id: linux-scsi@vger.kernel.org From: Nicholas Bellinger During recent perf testing with qla_target.c logic, dl_dbg() appeared as one of the top CPU consumers (~5% CPU) with small block random I/O even when no debug levels have been enabled. This patch moves the explict memset() in four qla_dbc.c functions within code blocks to where we know it will actually be used to save the extra wasted cycles. Cc: Andrew Vasquez Cc: Giridhar Malavali Cc: Roland Dreier Cc: Joern Engel Cc: James Bottomley Signed-off-by: Nicholas Bellinger --- drivers/scsi/qla2xxx/qla_dbg.c | 16 ++++++++-------- 1 files changed, 8 insertions(+), 8 deletions(-) diff --git a/drivers/scsi/qla2xxx/qla_dbg.c b/drivers/scsi/qla2xxx/qla_dbg.c index 07372de..cc32ec8 100644 --- a/drivers/scsi/qla2xxx/qla_dbg.c +++ b/drivers/scsi/qla2xxx/qla_dbg.c @@ -1676,11 +1676,11 @@ ql_dbg(uint32_t level, scsi_qla_host_t *vha, int32_t id, char *msg, ...) { uint32_t len; struct pci_dev *pdev = NULL; - memset(pbuf, 0, QL_DBG_BUF_LEN); - va_start(ap, msg); if ((level & ql2xextended_error_logging) == level) { + memset(pbuf, 0, QL_DBG_BUF_LEN); + if (vha != NULL) { pdev = vha->hw->pdev; /* : Message */ @@ -1724,11 +1724,11 @@ ql_dbg_pci(uint32_t level, struct pci_dev *pdev, int32_t id, char *msg, ...) { if (pdev == NULL) return; - memset(pbuf, 0, QL_DBG_BUF_LEN); - va_start(ap, msg); if ((level & ql2xextended_error_logging) == level) { + memset(pbuf, 0, QL_DBG_BUF_LEN); + /* : Message */ sprintf(pbuf, "%s [%s]-%04x: : ", QL_MSGHDR, dev_name(&(pdev->dev)), id + ql_dbg_offset); @@ -1763,11 +1763,11 @@ ql_log(uint32_t level, scsi_qla_host_t *vha, int32_t id, char *msg, ...) { uint32_t len; struct pci_dev *pdev = NULL; - memset(pbuf, 0, QL_DBG_BUF_LEN); - va_start(ap, msg); if (level <= ql_errlev) { + memset(pbuf, 0, QL_DBG_BUF_LEN); + if (vha != NULL) { pdev = vha->hw->pdev; /* : Message */ @@ -1823,11 +1823,11 @@ ql_log_pci(uint32_t level, struct pci_dev *pdev, int32_t id, char *msg, ...) { if (pdev == NULL) return; - memset(pbuf, 0, QL_DBG_BUF_LEN); - va_start(ap, msg); if (level <= ql_errlev) { + memset(pbuf, 0, QL_DBG_BUF_LEN); + /* : Message */ sprintf(pbuf, "%s [%s]-%04x: : ", QL_MSGHDR, dev_name(&(pdev->dev)), id); -- 1.7.2.5