| Message ID | 20181109022801.29979-1-dagostinelli@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Suppress the sparse warning ./include/linux/slab.h:332:43: warning: dubious: x & !y | expand |
On Thu, 8 Nov 2018, Darryl T. Agostinelli wrote: > Signed-off-by: Darryl T. Agostinelli <dagostinelli@gmail.com> > --- > include/linux/slab.h | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > > diff --git a/include/linux/slab.h b/include/linux/slab.h > index 918f374e7156..883b7f56bf35 100644 > --- a/include/linux/slab.h > +++ b/include/linux/slab.h > @@ -317,6 +317,7 @@ static __always_inline enum kmalloc_cache_type kmalloc_type(gfp_t flags) > int is_dma = 0; > int type_dma = 0; > int is_reclaimable; > + int y; > > #ifdef CONFIG_ZONE_DMA > is_dma = !!(flags & __GFP_DMA); > @@ -329,7 +330,10 @@ static __always_inline enum kmalloc_cache_type kmalloc_type(gfp_t flags) > * If an allocation is both __GFP_DMA and __GFP_RECLAIMABLE, return > * KMALLOC_DMA and effectively ignore __GFP_RECLAIMABLE > */ > - return type_dma + (is_reclaimable & !is_dma) * KMALLOC_RECLAIM; > + > + y = (is_reclaimable & (is_dma == 0 ? 1 : 0)); > + > + return type_dma + y * KMALLOC_RECLAIM; > } > > /* I agree with you that the function as written is less than pretty :) How does the assembly change as a result of this code change, however? This will be in the kmalloc() path so impacting the assembly to fix a sparse warning may not be warranted.
diff --git a/include/linux/slab.h b/include/linux/slab.h index 918f374e7156..883b7f56bf35 100644 --- a/include/linux/slab.h +++ b/include/linux/slab.h @@ -317,6 +317,7 @@ static __always_inline enum kmalloc_cache_type kmalloc_type(gfp_t flags) int is_dma = 0; int type_dma = 0; int is_reclaimable; + int y; #ifdef CONFIG_ZONE_DMA is_dma = !!(flags & __GFP_DMA); @@ -329,7 +330,10 @@ static __always_inline enum kmalloc_cache_type kmalloc_type(gfp_t flags) * If an allocation is both __GFP_DMA and __GFP_RECLAIMABLE, return * KMALLOC_DMA and effectively ignore __GFP_RECLAIMABLE */ - return type_dma + (is_reclaimable & !is_dma) * KMALLOC_RECLAIM; + + y = (is_reclaimable & (is_dma == 0 ? 1 : 0)); + + return type_dma + y * KMALLOC_RECLAIM; } /*
Signed-off-by: Darryl T. Agostinelli <dagostinelli@gmail.com> --- include/linux/slab.h | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)