[PATCH v6 5/8] x86/resctrl: Unwind the errors inside rdt_enable_ctx

Babu Moger
2023-07-19T23:22:29Z

rdt_enable_ctx() takes care of enabling the features provided during
resctrl mount. The error unwinding of rdt_enable_ctx is done from the
caller rdt_get_tree. This is not ideal and can cause some error unwinding
to be omitted.

Fix this by moving all the error unwinding inside rdt_enable_ctx.

Suggested-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Babu Moger <babu.moger@amd.com>
---
arch/x86/kernel/cpu/resctrl/rdtgroup.c | 31 +++++++++++++++++++++++--------
1 file changed, 23 insertions(+), 8 deletions(-)

diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
index 3010e3a1394d..9a7204f71d2d 100644
--- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
+++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
@@ -2381,15 +2381,31 @@ static int rdt_enable_ctx(struct rdt_fs_context *ctx)
{
int ret = 0;

- if (ctx->enable_cdpl2)
+ if (ctx->enable_cdpl2) {
ret = resctrl_arch_set_cdp_enabled(RDT_RESOURCE_L2, true);
+ if (ret)
+ goto out;
+ }

- if (!ret && ctx->enable_cdpl3)
+ if (ctx->enable_cdpl3) {
ret = resctrl_arch_set_cdp_enabled(RDT_RESOURCE_L3, true);
+ if (ret)
+ goto out_cdpl2;
+ }

- if (!ret && ctx->enable_mba_mbps)
+ if (ctx->enable_mba_mbps) {
ret = set_mba_sc(true);
+ if (ret)
+ goto out_cdpl3;
+ }

+ return 0;
+
+out_cdpl3:
+ resctrl_arch_set_cdp_enabled(RDT_RESOURCE_L3, false);
+out_cdpl2:
+ resctrl_arch_set_cdp_enabled(RDT_RESOURCE_L2, false);
+out:
return ret;
}

@@ -2497,13 +2513,13 @@ static int rdt_get_tree(struct fs_context *fc)
}

ret = rdt_enable_ctx(ctx);
- if (ret < 0)
- goto out_cdp;
+ if (ret)
+ goto out;

ret = schemata_list_create();
if (ret) {
schemata_list_destroy();
- goto out_mba;
+ goto out_ctx;
}

closid_init();
@@ -2562,10 +2578,9 @@ static int rdt_get_tree(struct fs_context *fc)
kernfs_remove(kn_info);
out_schemata_free:
schemata_list_destroy();
-out_mba:
+out_ctx:
if (ctx->enable_mba_mbps)
set_mba_sc(false);
-out_cdp:
cdp_disable_all();
out:
rdt_last_cmd_clear();