[PATCH v3 13/28] x86/sgx: Prepare for multiple LRUs

From: Haitao Huang
Date: Wed Jul 12 2023 - 19:03:18 EST


From: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>

Add sgx_can_reclaim() wrapper so that in a subsequent patch, multiple LRUs
can be used cleanly.

Signed-off-by: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>
Signed-off-by: Kristen Carlson Accardi <kristen@xxxxxxxxxxxxxxx>
Signed-off-by: Haitao Huang <haitao.huang@xxxxxxxxxxxxxxx>
Cc: Sean Christopherson <seanjc@xxxxxxxxxx>
---
arch/x86/kernel/cpu/sgx/main.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kernel/cpu/sgx/main.c b/arch/x86/kernel/cpu/sgx/main.c
index ea0698db8698..a829555b9675 100644
--- a/arch/x86/kernel/cpu/sgx/main.c
+++ b/arch/x86/kernel/cpu/sgx/main.c
@@ -390,10 +390,15 @@ static size_t sgx_reclaim_pages(size_t nr_to_scan, bool ignore_age)
return i;
}

+static bool sgx_can_reclaim(void)
+{
+ return !list_empty(&sgx_global_lru.reclaimable);
+}
+
static bool sgx_should_reclaim(unsigned long watermark)
{
return atomic_long_read(&sgx_nr_free_pages) < watermark &&
- !list_empty(&sgx_global_lru.reclaimable);
+ sgx_can_reclaim();
}

/*
@@ -589,7 +594,7 @@ struct sgx_epc_page *sgx_alloc_epc_page(void *owner, bool reclaim)
break;
}

- if (list_empty(&sgx_global_lru.reclaimable))
+ if (!sgx_can_reclaim())
return ERR_PTR(-ENOMEM);

if (!reclaim) {
--
2.25.1