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| author | Yury Norov (NVIDIA) <yury.norov@gmail.com> | 2025-08-14 22:09:36 +0300 |
|---|---|---|
| committer | Madhavan Srinivasan <maddy@linux.ibm.com> | 2026-04-01 06:51:07 +0300 |
| commit | bd77a34e9a619ee92c03cbb227ca86d814aa6601 (patch) | |
| tree | 5e8c7c7c1ac03e272e7d40194b917187c57112cd | |
| parent | f73338d089deedb4f4f1e49751c30b8b7f595ecd (diff) | |
| download | linux-bd77a34e9a619ee92c03cbb227ca86d814aa6601.tar.xz | |
powerpc: pci-ioda: Optimize pnv_ioda_pick_m64_pe()
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 <ajd@linux.ibm.com>
Signed-off-by: Yury Norov (NVIDIA) <yury.norov@gmail.com>
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Link: https://patch.msgid.link/20250814190936.381346-3-yury.norov@gmail.com
| -rw-r--r-- | arch/powerpc/platforms/powernv/pci-ioda.c | 19 |
1 files changed, 6 insertions, 13 deletions
diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c index 83f75d88e53b..32ecbc46e74b 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)) @@ -312,22 +312,15 @@ static struct pnv_ioda_pe *pnv_ioda_pick_m64_pe(struct pci_bus *bus, bool all) 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; |