| Message ID | 20211112145446.51210-1-r.bolshakov@yadro.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 69002c8ce914ef0ae22a6ea14b43bb30b9a9a6a8 |
| Headers | show |
| Series | scsi: qla2xxx: Format log strings only if needed | expand |
On Fri, 12 Nov 2021 17:54:46 +0300, Roman Bolshakov wrote: > Commit 598a90f2002c4 ("scsi: qla2xxx: add ring buffer for tracing debug > logs") introduced unconditional log string formatting to ql_dbg() even > if ql_dbg_log event is disabled. It harms performance because some > strings are formatted in fastpath and/or interrupt context. > > Applied to 5.16/scsi-fixes, thanks! [1/1] scsi: qla2xxx: Format log strings only if needed https://git.kernel.org/mkp/scsi/c/69002c8ce914
diff --git a/drivers/scsi/qla2xxx/qla_dbg.c b/drivers/scsi/qla2xxx/qla_dbg.c index 25549a8a2d72..7cf1f78cbaee 100644 --- a/drivers/scsi/qla2xxx/qla_dbg.c +++ b/drivers/scsi/qla2xxx/qla_dbg.c @@ -2491,6 +2491,9 @@ ql_dbg(uint level, scsi_qla_host_t *vha, uint id, const char *fmt, ...) struct va_format vaf; char pbuf[64]; + if (!ql_mask_match(level) && !trace_ql_dbg_log_enabled()) + return; + va_start(va, fmt); vaf.fmt = fmt;
Commit 598a90f2002c4 ("scsi: qla2xxx: add ring buffer for tracing debug logs") introduced unconditional log string formatting to ql_dbg() even if ql_dbg_log event is disabled. It harms performance because some strings are formatted in fastpath and/or interrupt context. Cc: Rajan Shanmugavelu <rajan.shanmugavelu@oracle.com> Cc: stable@vger.kernel.org Fixes: 598a90f2002c4 ("scsi: qla2xxx: add ring buffer for tracing debug logs") Signed-off-by: Roman Bolshakov <r.bolshakov@yadro.com> --- drivers/scsi/qla2xxx/qla_dbg.c | 3 +++ 1 file changed, 3 insertions(+)