audit_filter_uring(), audit_filter_inode_name() are substantially
similar to audit_filter_syscall(). Move the core logic to
__audit_filter_op() which can be parametrized for all three.
On a Skylakex system, getpid() latency (all results aggregated
across 12 boot cycles):
Min Mean Median Max pstdev
(ns) (ns) (ns) (ns)
- 196.63 207.86 206.60 230.98 (+- 3.92%)
+ 183.73 196.95 192.31 232.49 (+- 6.04%)
Performance counter stats for 'bin/getpid' (3 runs) go from:
cycles 805.58 ( +- 4.11% )
instructions 1654.11 ( +- .05% )
IPC 2.06 ( +- 3.39% )
branches 430.02 ( +- .05% )
branch-misses 1.55 ( +- 7.09% )
L1-dcache-loads 440.01 ( +- .09% )
L1-dcache-load-misses 9.05 ( +- 74.03% )
to:
cycles 765.37 ( +- 6.66% )
instructions 1677.07 ( +- 0.04% )
IPC 2.20 ( +- 5.90% )
branches 431.10 ( +- 0.04% )
branch-misses 1.60 ( +- 11.25% )
L1-dcache-loads 521.04 ( +- 0.05% )
L1-dcache-load-misses 6.92 ( +- 77.60% )
(Both aggregated over 12 boot cycles.)
The increased L1-dcache-loads are due to some intermediate values now
coming from the stack.
The improvement in cycles is due to a slightly denser loop (the list
parameter in the list_for_each_entry_rcu() exit check now comes from
a register rather than a constant as before.)
Signed-off-by: Ankur Arora <ankur.a.ar...@oracle.com>
---
kernel/auditsc.c | 76 +++++++++++++++++++++++++-----------------------
1 file changed, 39 insertions(+), 37 deletions(-)
diff --git a/kernel/auditsc.c b/kernel/auditsc.c
index 2206cdf1ba2c..4991348e300a 100644
--- a/kernel/auditsc.c
+++ b/kernel/auditsc.c
@@ -807,6 +807,40 @@ static int audit_in_mask(const struct audit_krule *rule,
unsigned long val)
return rule->mask[word] & bit;
}
+/**
+ * __audit_filter_op - common filter helper for operations (syscall/uring/etc)
+ * @tsk: associated task
+ * @ctx: audit context
+ * @list: audit filter list
+ * @name: audit_name (can be NULL)
+ * @op: current syscall/uring_op
+ *
+ * Run the udit filters specified in @list against @tsk using @ctx,
+ * @name, and @op, as necessary; the caller is responsible for ensuring
+ * that the call is made while the RCU read lock is held. The @name
+ * parameter can be NULL, but all others must be specified.
+ * Returns 1/true if the filter finds a match, 0/false if none are found.
+ */
+static int __audit_filter_op(struct task_struct *tsk,
+ struct audit_context *ctx,
+ struct list_head *list,
+ struct audit_names *name,
+ unsigned long op)
+{
+ struct audit_entry *e;
+ enum audit_state state;
+
+ list_for_each_entry_rcu(e, list, list) {
+ if (audit_in_mask(&e->rule, op) &&
+ audit_filter_rules(tsk, &e->rule, ctx, name,
+ &state, false)) {
+ ctx->current_state = state;
+ return 1;
+ }
+ }
+ return 0;
+}
+
/**
* audit_filter_uring - apply filters to an io_uring operation
* @tsk: associated task
@@ -815,23 +849,12 @@ static int audit_in_mask(const struct audit_krule *rule,
unsigned long val)
static void audit_filter_uring(struct task_struct *tsk,
struct audit_context *ctx)
{
- struct audit_entry *e;
- enum audit_state state;
-
if (auditd_test_task(tsk))
return;
rcu_read_lock();
- list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_URING_EXIT],
- list) {
- if (audit_in_mask(&e->rule, ctx->uring_op) &&
- audit_filter_rules(tsk, &e->rule, ctx, NULL, &state,
- false)) {
- rcu_read_unlock();
- ctx->current_state = state;
- return;
- }
- }
+ __audit_filter_op(tsk, ctx, &audit_filter_list[AUDIT_FILTER_URING_EXIT],
+ NULL, ctx->uring_op);
rcu_read_unlock();
}
@@ -843,25 +866,13 @@ static void audit_filter_uring(struct task_struct *tsk,
static void audit_filter_syscall(struct task_struct *tsk,
struct audit_context *ctx)
{
- struct audit_entry *e;
- enum audit_state state;
- unsigned long major = ctx->major;
-
if (auditd_test_task(tsk))
return;
rcu_read_lock();
- list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_EXIT], list)
{
- if (audit_in_mask(&e->rule, major) &&
- audit_filter_rules(tsk, &e->rule, ctx, NULL,
- &state, false)) {
- rcu_read_unlock();
- ctx->current_state = state;
- return;
- }
- }
+ __audit_filter_op(tsk, ctx, &audit_filter_list[AUDIT_FILTER_EXIT],
+ NULL, ctx->major);
rcu_read_unlock();
- return;
}
/*
@@ -873,17 +884,8 @@ static int audit_filter_inode_name(struct task_struct *tsk,
struct audit_context *ctx) {
int h = audit_hash_ino((u32)n->ino);
struct list_head *list = &audit_inode_hash[h];
- struct audit_entry *e;
- enum audit_state state;
- list_for_each_entry_rcu(e, list, list) {
- if (audit_in_mask(&e->rule, ctx->major) &&
- audit_filter_rules(tsk, &e->rule, ctx, n, &state, false)) {
- ctx->current_state = state;
- return 1;
- }
- }
- return 0;
+ return __audit_filter_op(tsk, ctx, list, n, ctx->major);
}
/* At syscall exit time, this filter is called if any audit_names have been
--
2.31.1
--
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