From 6ba2a2924dcf6026de5078ba7025248a580d8bde Mon Sep 17 00:00:00 2001 From: Nicholas Piggin Date: Sun, 23 Jan 2022 22:00:40 +1000 Subject: [PATCH] KVM: PPC: Book3S HV: Use IDA allocator for LPID allocator This removes the fixed-size lpid_inuse array. Signed-off-by: Nicholas Piggin Reviewed-by: Fabiano Rosas Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/20220123120043.3586018-4-npiggin@gmail.com --- arch/powerpc/kvm/powerpc.c | 25 +++++++++++++------------ 1 file changed, 13 insertions(+), 12 deletions(-) diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c index 1a0e3ede891f..32561192cf12 100644 --- a/arch/powerpc/kvm/powerpc.c +++ b/arch/powerpc/kvm/powerpc.c @@ -2496,20 +2496,22 @@ out: return r; } -static unsigned long lpid_inuse[BITS_TO_LONGS(KVMPPC_NR_LPIDS)]; +static DEFINE_IDA(lpid_inuse); static unsigned long nr_lpids; long kvmppc_alloc_lpid(void) { - long lpid; + int lpid; - do { - lpid = find_first_zero_bit(lpid_inuse, KVMPPC_NR_LPIDS); - if (lpid >= nr_lpids) { + /* The host LPID must always be 0 (allocation starts at 1) */ + lpid = ida_alloc_range(&lpid_inuse, 1, nr_lpids - 1, GFP_KERNEL); + if (lpid < 0) { + if (lpid == -ENOMEM) + pr_err("%s: Out of memory\n", __func__); + else pr_err("%s: No LPIDs free\n", __func__); - return -ENOMEM; - } - } while (test_and_set_bit(lpid, lpid_inuse)); + return -ENOMEM; + } return lpid; } @@ -2517,15 +2519,14 @@ EXPORT_SYMBOL_GPL(kvmppc_alloc_lpid); void kvmppc_free_lpid(long lpid) { - clear_bit(lpid, lpid_inuse); + ida_free(&lpid_inuse, lpid); } EXPORT_SYMBOL_GPL(kvmppc_free_lpid); +/* nr_lpids_param includes the host LPID */ void kvmppc_init_lpid(unsigned long nr_lpids_param) { - nr_lpids = min_t(unsigned long, KVMPPC_NR_LPIDS, nr_lpids_param); - memset(lpid_inuse, 0, sizeof(lpid_inuse)); - set_bit(0, lpid_inuse); /* The host LPID must always be 0 */ + nr_lpids = nr_lpids_param; } EXPORT_SYMBOL_GPL(kvmppc_init_lpid);