2024-01-22 06:26:32

by Kyle Huey

[permalink] [raw]
Subject: [PATCH v5 2/4] perf/bpf: Remove unneeded uses_default_overflow_handler.

Now that struct perf_event's orig_overflow_handler is gone, there's no need
for the functions and macros to support looking past overflow_handler to
orig_overflow_handler.

This patch is solely a refactoring and results in no behavior change.

Signed-off-by: Kyle Huey <[email protected]>
Acked-by: Will Deacon <[email protected]>
Acked-by: Song Liu <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
---
arch/arm/kernel/hw_breakpoint.c | 8 ++++----
arch/arm64/kernel/hw_breakpoint.c | 4 ++--
include/linux/perf_event.h | 16 ++--------------
3 files changed, 8 insertions(+), 20 deletions(-)

diff --git a/arch/arm/kernel/hw_breakpoint.c b/arch/arm/kernel/hw_breakpoint.c
index dc0fb7a81371..054e9199f30d 100644
--- a/arch/arm/kernel/hw_breakpoint.c
+++ b/arch/arm/kernel/hw_breakpoint.c
@@ -626,7 +626,7 @@ int hw_breakpoint_arch_parse(struct perf_event *bp,
hw->address &= ~alignment_mask;
hw->ctrl.len <<= offset;

- if (uses_default_overflow_handler(bp)) {
+ if (is_default_overflow_handler(bp)) {
/*
* Mismatch breakpoints are required for single-stepping
* breakpoints.
@@ -798,7 +798,7 @@ static void watchpoint_handler(unsigned long addr, unsigned int fsr,
* Otherwise, insert a temporary mismatch breakpoint so that
* we can single-step over the watchpoint trigger.
*/
- if (!uses_default_overflow_handler(wp))
+ if (!is_default_overflow_handler(wp))
continue;
step:
enable_single_step(wp, instruction_pointer(regs));
@@ -811,7 +811,7 @@ static void watchpoint_handler(unsigned long addr, unsigned int fsr,
info->trigger = addr;
pr_debug("watchpoint fired: address = 0x%x\n", info->trigger);
perf_bp_event(wp, regs);
- if (uses_default_overflow_handler(wp))
+ if (is_default_overflow_handler(wp))
enable_single_step(wp, instruction_pointer(regs));
}

@@ -886,7 +886,7 @@ static void breakpoint_handler(unsigned long unknown, struct pt_regs *regs)
info->trigger = addr;
pr_debug("breakpoint fired: address = 0x%x\n", addr);
perf_bp_event(bp, regs);
- if (uses_default_overflow_handler(bp))
+ if (is_default_overflow_handler(bp))
enable_single_step(bp, addr);
goto unlock;
}
diff --git a/arch/arm64/kernel/hw_breakpoint.c b/arch/arm64/kernel/hw_breakpoint.c
index 35225632d70a..db2a1861bb97 100644
--- a/arch/arm64/kernel/hw_breakpoint.c
+++ b/arch/arm64/kernel/hw_breakpoint.c
@@ -654,7 +654,7 @@ static int breakpoint_handler(unsigned long unused, unsigned long esr,
perf_bp_event(bp, regs);

/* Do we need to handle the stepping? */
- if (uses_default_overflow_handler(bp))
+ if (is_default_overflow_handler(bp))
step = 1;
unlock:
rcu_read_unlock();
@@ -733,7 +733,7 @@ static u64 get_distance_from_watchpoint(unsigned long addr, u64 val,
static int watchpoint_report(struct perf_event *wp, unsigned long addr,
struct pt_regs *regs)
{
- int step = uses_default_overflow_handler(wp);
+ int step = is_default_overflow_handler(wp);
struct arch_hw_breakpoint *info = counter_arch_bp(wp);

info->trigger = addr;
diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index c7f54fd74d89..c8bd5bb6610c 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -1341,8 +1341,9 @@ extern int perf_event_output(struct perf_event *event,
struct pt_regs *regs);

static inline bool
-__is_default_overflow_handler(perf_overflow_handler_t overflow_handler)
+is_default_overflow_handler(struct perf_event *event)
{
+ perf_overflow_handler_t overflow_handler = event->overflow_handler;
if (likely(overflow_handler == perf_event_output_forward))
return true;
if (unlikely(overflow_handler == perf_event_output_backward))
@@ -1350,19 +1351,6 @@ __is_default_overflow_handler(perf_overflow_handler_t overflow_handler)
return false;
}

-#define is_default_overflow_handler(event) \
- __is_default_overflow_handler((event)->overflow_handler)
-
-#ifdef CONFIG_BPF_SYSCALL
-static inline bool uses_default_overflow_handler(struct perf_event *event)
-{
- return is_default_overflow_handler(event);
-}
-#else
-#define uses_default_overflow_handler(event) \
- is_default_overflow_handler(event)
-#endif
-
extern void
perf_event_header__init_id(struct perf_event_header *header,
struct perf_sample_data *data,
--
2.34.1