linux-kernel - [PATCH v5 15/27] ata: let compiler optimize out ata_eh_set

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20200326155822.19400-16-b.zolnierkie@samsung.com>
Date:   Thu, 26 Mar 2020 16:58:10 +0100
From:   Bartlomiej Zolnierkiewicz <b.zolnierkie@...sung.com>
To:     Jens Axboe <axboe@...nel.dk>
Cc:     Michael Schmitz <schmitzmic@...il.com>,
        Geert Uytterhoeven <geert@...ux-m68k.org>,
        Christoph Hellwig <hch@....de>, linux-ide@...r.kernel.org,
        linux-m68k@...ts.linux-m68k.org, linux-kernel@...r.kernel.org,
        b.zolnierkie@...sung.com
Subject: [PATCH v5 15/27] ata: let compiler optimize out ata_eh_set_lpm() on
 non-SATA hosts

Add !IS_ENABLED(CONFIG_SATA_HOST) to ata_eh_set_lpm() to allow
compiler to optimize out the function for non-SATA configs (for
PATA hosts "ap && !ap->ops->set_lpm" condition is always true so
it's sufficient for the function to return zero).

Code size savings on m68k arch using (modified) atari_defconfig:

   text    data     bss     dec     hex filename
before:
  17353      18       0   17371    43db drivers/ata/libata-eh.o
after:
  16607      18       0   16625    40f1 drivers/ata/libata-eh.o

Reviewed-by: Christoph Hellwig <hch@....de>
Signed-off-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@...sung.com>
---
 drivers/ata/libata-eh.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c
index 04275f4c8d36..8dc33b6832f0 100644
--- a/drivers/ata/libata-eh.c
+++ b/drivers/ata/libata-eh.c
@@ -3443,7 +3443,8 @@ static int ata_eh_set_lpm(struct ata_link *link, enum ata_lpm_policy policy,
 	int rc;
 
 	/* if the link or host doesn't do LPM, noop */
-	if ((link->flags & ATA_LFLAG_NO_LPM) || (ap && !ap->ops->set_lpm))
+	if (!IS_ENABLED(CONFIG_SATA_HOST) ||
+	    (link->flags & ATA_LFLAG_NO_LPM) || (ap && !ap->ops->set_lpm))
 		return 0;
 
 	/*
-- 
2.24.1