forked from luck/tmp_suning_uos_patched
ef3fb2422f
A bug in the gcc-6.0 prerelease version caused at least one driver (lpfc) to have excessive stack usage when dealing with wwn data, on the ARM architecture. lpfc_scsi.c: In function 'lpfc_find_next_oas_lun': lpfc_scsi.c:117:1: warning: the frame size of 1152 bytes is larger than 1024 bytes [-Wframe-larger-than=] I have reported this as a gcc regression in https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70232 However, using a better implementation of wwn_to_u64() not only helps with the particular gcc problem but also leads to better object code for any version or architecture. The kernel already provides get_unaligned_be64() and put_unaligned_be64() helper functions that provide an optimized implementation with the desired semantics. The lpfc_find_next_oas_lun() function in the example that grew from 1146 bytes to 5144 bytes when moving from gcc-5.3 to gcc-6.0 is now 804 bytes, as the optimized get_unaligned_be64() load can be done in three instructions. The stack usage is now down to 28 bytes from 128 bytes with gcc-5.3 before. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Hannes Reinicke <hare@suse.de> Reviewed-by: Ewan Milne <emilne@redhat.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> |
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| .. | ||
| fc | ||
| fc_encode.h | ||
| fc_frame.h | ||
| fcoe_sysfs.h | ||
| iscsi_if.h | ||
| iscsi_proto.h | ||
| iser.h | ||
| libfc.h | ||
| libfcoe.h | ||
| libiscsi_tcp.h | ||
| libiscsi.h | ||
| libsas.h | ||
| osd_attributes.h | ||
| osd_initiator.h | ||
| osd_ore.h | ||
| osd_protocol.h | ||
| osd_sec.h | ||
| osd_sense.h | ||
| osd_types.h | ||
| sas_ata.h | ||
| sas.h | ||
| scsi_bsg_iscsi.h | ||
| scsi_cmnd.h | ||
| scsi_common.h | ||
| scsi_dbg.h | ||
| scsi_device.h | ||
| scsi_devinfo.h | ||
| scsi_dh.h | ||
| scsi_driver.h | ||
| scsi_eh.h | ||
| scsi_host.h | ||
| scsi_ioctl.h | ||
| scsi_proto.h | ||
| scsi_tcq.h | ||
| scsi_transport_fc.h | ||
| scsi_transport_iscsi.h | ||
| scsi_transport_sas.h | ||
| scsi_transport_spi.h | ||
| scsi_transport_srp.h | ||
| scsi_transport.h | ||
| scsi.h | ||
| scsicam.h | ||
| sg.h | ||
| srp.h | ||