From a4bc676ed5c3f53781cc342b73097eb7e8d43fa5 Mon Sep 17 00:00:00 2001 From: Oliver O'Halloran Date: Wed, 22 Jul 2020 16:57:09 +1000 Subject: powerpc/powernv/pci: Refactor pnv_ioda_alloc_pe() Rework the PE allocation logic to allow allocating blocks of PEs rather than individually. We'll use this to allocate contigious blocks of PEs for the SR-IOVs. This patch also adds code to pnv_ioda_alloc_pe() and pnv_ioda_reserve_pe() to use the existing, but unused, phb->pe_alloc_mutex. Currently these functions use atomic bit ops to release a currently allocated PE number. However, the pnv_ioda_alloc_pe() wants to have exclusive access to the bit map while scanning for hole large enough to accomodate the allocation size. Signed-off-by: Oliver O'Halloran Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20200722065715.1432738-10-oohall@gmail.com --- arch/powerpc/platforms/powernv/pci-ioda.c | 41 +++++++++++++++++++++++++------ 1 file changed, 33 insertions(+), 8 deletions(-) (limited to 'arch/powerpc/platforms/powernv/pci-ioda.c') diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c index 2d36a9ebf0e9..c9c25fb0783c 100644 --- a/arch/powerpc/platforms/powernv/pci-ioda.c +++ b/arch/powerpc/platforms/powernv/pci-ioda.c @@ -145,23 +145,45 @@ static void pnv_ioda_reserve_pe(struct pnv_phb *phb, int pe_no) return; } + mutex_lock(&phb->ioda.pe_alloc_mutex); if (test_and_set_bit(pe_no, phb->ioda.pe_alloc)) pr_debug("%s: PE %x was reserved on PHB#%x\n", __func__, pe_no, phb->hose->global_number); + mutex_unlock(&phb->ioda.pe_alloc_mutex); pnv_ioda_init_pe(phb, pe_no); } -struct pnv_ioda_pe *pnv_ioda_alloc_pe(struct pnv_phb *phb) +struct pnv_ioda_pe *pnv_ioda_alloc_pe(struct pnv_phb *phb, int count) { - long pe; + struct pnv_ioda_pe *ret = NULL; + int run = 0, pe, i; + mutex_lock(&phb->ioda.pe_alloc_mutex); + + /* scan backwards for a run of @count cleared bits */ for (pe = phb->ioda.total_pe_num - 1; pe >= 0; pe--) { - if (!test_and_set_bit(pe, phb->ioda.pe_alloc)) - return pnv_ioda_init_pe(phb, pe); + if (test_bit(pe, phb->ioda.pe_alloc)) { + run = 0; + continue; + } + + run++; + if (run == count) + break; } + if (run != count) + goto out; - return NULL; + for (i = pe; i < pe + count; i++) { + set_bit(i, phb->ioda.pe_alloc); + pnv_ioda_init_pe(phb, i); + } + ret = &phb->ioda.pe_array[pe]; + +out: + mutex_unlock(&phb->ioda.pe_alloc_mutex); + return ret; } void pnv_ioda_free_pe(struct pnv_ioda_pe *pe) @@ -173,7 +195,10 @@ void pnv_ioda_free_pe(struct pnv_ioda_pe *pe) WARN_ON(pe->npucomp); /* NPUs for nvlink are not supposed to be freed */ kfree(pe->npucomp); memset(pe, 0, sizeof(struct pnv_ioda_pe)); + + mutex_lock(&phb->ioda.pe_alloc_mutex); clear_bit(pe_num, phb->ioda.pe_alloc); + mutex_unlock(&phb->ioda.pe_alloc_mutex); } /* The default M64 BAR is shared by all PEs */ @@ -976,7 +1001,7 @@ static struct pnv_ioda_pe *pnv_ioda_setup_dev_PE(struct pci_dev *dev) if (pdn->pe_number != IODA_INVALID_PE) return NULL; - pe = pnv_ioda_alloc_pe(phb); + pe = pnv_ioda_alloc_pe(phb, 1); if (!pe) { pr_warn("%s: Not enough PE# available, disabling device\n", pci_name(dev)); @@ -1047,7 +1072,7 @@ static struct pnv_ioda_pe *pnv_ioda_setup_bus_PE(struct pci_bus *bus, bool all) /* The PE number isn't pinned by M64 */ if (!pe) - pe = pnv_ioda_alloc_pe(phb); + pe = pnv_ioda_alloc_pe(phb, 1); if (!pe) { pr_warn("%s: Not enough PE# available for PCI bus %04x:%02x\n", @@ -3065,7 +3090,7 @@ static void __init pnv_pci_init_ioda_phb(struct device_node *np, pnv_ioda_reserve_pe(phb, phb->ioda.root_pe_idx); } else { /* otherwise just allocate one */ - root_pe = pnv_ioda_alloc_pe(phb); + root_pe = pnv_ioda_alloc_pe(phb, 1); phb->ioda.root_pe_idx = root_pe->pe_number; } -- cgit v1.2.3-59-g8ed1b