UBI: fastmap: avoid multiple be32_to_cpu() when unneccesary

Boris Brezillon · richardweinberger · commit 4c368421bc1a · 2016-10-02T22:48:14.000+02:00
process_pool_aeb() does several times the be32_to_cpu(new_vh-&gt;vol_id)
operation. Create a temporary variable and do it once.

Signed-off-by: Boris Brezillon &lt;boris.brezillon@free-electrons.com&gt;
Signed-off-by: Richard Weinberger &lt;richard@nod.at&gt;
diff --git a/drivers/mtd/ubi/fastmap.c b/drivers/mtd/ubi/fastmap.c
@@ -370,24 +370,24 @@ static int process_pool_aeb(struct ubi_device *ubi, struct ubi_attach_info *ai,
 			    struct ubi_vid_hdr *new_vh,
 			    struct ubi_ainf_peb *new_aeb)
 {
+	int vol_id = be32_to_cpu(new_vh->vol_id);
 	struct ubi_ainf_volume *av;
 
-	if (be32_to_cpu(new_vh->vol_id) == UBI_FM_SB_VOLUME_ID ||
-		be32_to_cpu(new_vh->vol_id) == UBI_FM_DATA_VOLUME_ID) {
+	if (vol_id == UBI_FM_SB_VOLUME_ID || vol_id == UBI_FM_DATA_VOLUME_ID) {
 		kmem_cache_free(ai->aeb_slab_cache, new_aeb);
 
 		return 0;
 	}
 
 	/* Find the volume this SEB belongs to */
-	av = ubi_find_av(ai, be32_to_cpu(new_vh->vol_id));
+	av = ubi_find_av(ai, vol_id);
 	if (!av) {
 		ubi_err(ubi, "orphaned volume in fastmap pool!");
 		kmem_cache_free(ai->aeb_slab_cache, new_aeb);
 		return UBI_BAD_FASTMAP;
 	}
 
-	ubi_assert(be32_to_cpu(new_vh->vol_id) == av->vol_id);
+	ubi_assert(vol_id == av->vol_id);
 
 	return update_vol(ubi, ai, av, new_vh, new_aeb);
 }

Original file line number	Diff line number	Diff line change
`@@ -370,24 +370,24 @@ static int process_pool_aeb(struct ubi_device ubi, struct ubi_attach_info ai,`
`370`	`370`	`struct ubi_vid_hdr *new_vh,`
`371`	`371`	`struct ubi_ainf_peb *new_aeb)`
`372`	`372`	`{`
	`373`	`+ int vol_id = be32_to_cpu(new_vh->vol_id);`
`373`	`374`	`struct ubi_ainf_volume *av;`
`374`	`375`
`375`		`- if (be32_to_cpu(new_vh->vol_id) == UBI_FM_SB_VOLUME_ID \|\|`
`376`		`- be32_to_cpu(new_vh->vol_id) == UBI_FM_DATA_VOLUME_ID) {`
	`376`	`+ if (vol_id == UBI_FM_SB_VOLUME_ID \|\| vol_id == UBI_FM_DATA_VOLUME_ID) {`
`377`	`377`	`kmem_cache_free(ai->aeb_slab_cache, new_aeb);`
`378`	`378`
`379`	`379`	`return 0;`
`380`	`380`	`}`
`381`	`381`
`382`	`382`	`/* Find the volume this SEB belongs to */`
`383`		`- av = ubi_find_av(ai, be32_to_cpu(new_vh->vol_id));`
	`383`	`+ av = ubi_find_av(ai, vol_id);`
`384`	`384`	`if (!av) {`
`385`	`385`	`ubi_err(ubi, "orphaned volume in fastmap pool!");`
`386`	`386`	`kmem_cache_free(ai->aeb_slab_cache, new_aeb);`
`387`	`387`	`return UBI_BAD_FASTMAP;`
`388`	`388`	`}`
`389`	`389`
`390`		`- ubi_assert(be32_to_cpu(new_vh->vol_id) == av->vol_id);`
	`390`	`+ ubi_assert(vol_id == av->vol_id);`
`391`	`391`
`392`	`392`	`return update_vol(ubi, ai, av, new_vh, new_aeb);`
`393`	`393`	`}`