ata: add CONFIG_SATA_HOST=n version of ata_ncq_enabled()

When CONFIG_SATA_HOST=n there are no NCQ capable host drivers built so it is safe to hardwire ata_ncq_enabled() to always return zero. Code size savings on m68k arch using (modified) atari_defconfig: text data bss dec hex filename before: 37820 572 40 38432 9620 drivers/ata/libata-core.o 21040 105 576 21721 54d9 drivers/ata/libata-scsi.o 17405 18 0 17423 440f drivers/ata/libata-eh.o after: 37582 572 40 38194 9532 drivers/ata/libata-core.o 20702 105 576 21383 5387 drivers/ata/libata-scsi.o 17353 18 0 17371 43db drivers/ata/libata-eh.o

Bartlomiej Zolnierkiewicz committed 6 years ago

Commit 7caa30e1 parent a9b2c121 file · +2 −0Browse files

Showing the changes to include/linux (1 of 1 file). Show all

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include/linux/libata.h+2−0

@@ -1633,6 +1633,8 @@ extern struct ata_device ata_dev_next(struct ata_device dev, · 1632 unmodified lines
1633	1633	*/
1634	1634	static inline int ata_ncq_enabled(struct ata_device *dev)
1635	1635	{
	1636	+ if (!IS_ENABLED(CONFIG_SATA_HOST))
	1637	+ return 0;
1636	1638	return (dev->flags & (ATA_DFLAG_PIO \| ATA_DFLAG_NCQ_OFF \|
1637	1639	ATA_DFLAG_NCQ)) == ATA_DFLAG_NCQ;
1638	1640	}