From: "Yury Norov (NVIDIA)" <yury.no...@gmail.com>
bitmap_empty() in pnv_ioda_pick_m64_pe() is O(N) and useless because
the following find_next_bit() does the same work.
Drop it, and while there replace a while() loop with the dedicated
for_each_set_bit().
Reviewed-by: Andrew Donnellan <a...@linux.ibm.com>
Signed-off-by: Yury Norov (NVIDIA) <yury.no...@gmail.com>
---
arch/powerpc/platforms/powernv/pci-ioda.c | 19 ++++++-------------
1 file changed, 6 insertions(+), 13 deletions(-)
diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c
b/arch/powerpc/platforms/powernv/pci-ioda.c
index 2a4b916205c1..23b1db3f15a9 100644
--- a/arch/powerpc/platforms/powernv/pci-ioda.c
+++ b/arch/powerpc/platforms/powernv/pci-ioda.c
@@ -295,7 +295,7 @@ static struct pnv_ioda_pe *pnv_ioda_pick_m64_pe(struct
pci_bus *bus, bool all)
unsigned long *pe_alloc __free(bitmap) = NULL;
struct pnv_phb *phb = pci_bus_to_pnvhb(bus);
struct pnv_ioda_pe *master_pe, *pe;
- int i;
+ unsigned int i;
/* Root bus shouldn't use M64 */
if (pci_is_root_bus(bus))
@@ -311,23 +311,16 @@ static struct pnv_ioda_pe *pnv_ioda_pick_m64_pe(struct
pci_bus *bus, bool all)
/* Figure out reserved PE numbers by the PE */
pnv_ioda_reserve_m64_pe(bus, pe_alloc, all);
- /*
- * the current bus might not own M64 window and that's all
- * contributed by its child buses. For the case, we needn't
- * pick M64 dependent PE#.
- */
- if (bitmap_empty(pe_alloc, phb->ioda.total_pe_num)) {
- return NULL;
- }
-
/*
* Figure out the master PE and put all slave PEs to master
* PE's list to form compound PE.
+ *
+ * The current bus might not own M64 window and that's all
+ * contributed by its child buses. For the case, we needn't
+ * pick M64 dependent PE#.
*/
master_pe = NULL;
- i = -1;
- while ((i = find_next_bit(pe_alloc, phb->ioda.total_pe_num, i + 1)) <
- phb->ioda.total_pe_num) {
+ for_each_set_bit(i, pe_alloc, phb->ioda.total_pe_num) {
pe = &phb->ioda.pe_array[i];
phb->ioda.m64_segmap[pe->pe_number] = pe->pe_number;
--
2.43.0
