[RFC PATCH 14/20] x86/sgx: Expose sgx_reclaim_pages() for use by EPC cgroup

From: Kristen Carlson Accardi
Date: Thu Sep 22 2022 - 13:13:28 EST


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

Expose the top-level reclaim function as sgx_reclaim_epc_pages() for use
by the upcoming EPC cgroup, which will initiate reclaim to enforce
changes to high/max limits.

Signed-off-by: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>
Signed-off-by: Kristen Carlson Accardi <kristen@xxxxxxxxxxxxxxx>
Cc: Sean Christopherson <seanjc@xxxxxxxxxx>
---
arch/x86/kernel/cpu/sgx/main.c | 9 +++++----
arch/x86/kernel/cpu/sgx/sgx.h | 1 +
2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kernel/cpu/sgx/main.c b/arch/x86/kernel/cpu/sgx/main.c
index ac49346302ed..1791881aa1b1 100644
--- a/arch/x86/kernel/cpu/sgx/main.c
+++ b/arch/x86/kernel/cpu/sgx/main.c
@@ -281,6 +281,7 @@ static void sgx_reclaimer_write(struct sgx_epc_page *epc_page,

/**
* sgx_reclaim_pages() - Reclaim EPC pages from the consumers
+ * sgx_reclaim_epc_pages() - Reclaim EPC pages from the consumers
* @nr_to_scan: Number of EPC pages to scan for reclaim
* @ignore_age: Reclaim a page even if it is young
*
@@ -298,7 +299,7 @@ static void sgx_reclaimer_write(struct sgx_epc_page *epc_page,
*
* Return: number of EPC pages reclaimed
*/
-static int sgx_reclaim_pages(int nr_to_scan, bool ignore_age)
+int sgx_reclaim_epc_pages(int nr_to_scan, bool ignore_age)
{
struct sgx_backing backing[SGX_MAX_NR_TO_RECLAIM];
struct sgx_encl_page *encl_page;
@@ -405,7 +406,7 @@ static bool sgx_should_reclaim(unsigned long watermark)
void sgx_reclaim_direct(void)
{
if (sgx_should_reclaim(SGX_NR_LOW_PAGES))
- sgx_reclaim_pages(SGX_NR_TO_SCAN, false);
+ sgx_reclaim_epc_pages(SGX_NR_TO_SCAN, false);
}

static int ksgxd(void *p)
@@ -431,7 +432,7 @@ static int ksgxd(void *p)
sgx_should_reclaim(SGX_NR_HIGH_PAGES));

if (sgx_should_reclaim(SGX_NR_HIGH_PAGES))
- sgx_reclaim_pages(SGX_NR_TO_SCAN, false);
+ sgx_reclaim_epc_pages(SGX_NR_TO_SCAN, false);
}

return 0;
@@ -606,7 +607,7 @@ struct sgx_epc_page *sgx_alloc_epc_page(void *owner, bool reclaim)
break;
}

- sgx_reclaim_pages(SGX_NR_TO_SCAN, false);
+ sgx_reclaim_epc_pages(SGX_NR_TO_SCAN, false);
}

if (sgx_should_reclaim(SGX_NR_LOW_PAGES))
diff --git a/arch/x86/kernel/cpu/sgx/sgx.h b/arch/x86/kernel/cpu/sgx/sgx.h
index 76eae4ecbf87..a2042303a666 100644
--- a/arch/x86/kernel/cpu/sgx/sgx.h
+++ b/arch/x86/kernel/cpu/sgx/sgx.h
@@ -113,6 +113,7 @@ void sgx_reclaim_direct(void);
void sgx_record_epc_page(struct sgx_epc_page *page, unsigned long flags);
int sgx_drop_epc_page(struct sgx_epc_page *page);
struct sgx_epc_page *sgx_alloc_epc_page(void *owner, bool reclaim);
+int sgx_reclaim_epc_pages(int nr_to_scan, bool ignore_age);

void sgx_ipi_cb(void *info);

--
2.37.3