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// SPDX-License-Identifier: GPL-2.0 // Copyright (C) 2025 Google LLC. //! Keep track of statistics for binder_logs. use crate::defs::*;use kernel::sync::atomic::{ordering::Relaxed, Atomic};use kernel::{ioctl::_IOC_NR, seq_file::SeqFile, seq_print}; const BC_COUNT: usize = _IOC_NR(BC_FREEZE_NOTIFICATION_DONE) as usize + 1;const BR_COUNT: usize = _IOC_NR(BR_CLEAR_FREEZE_NOTIFICATION_DONE) as usize + 1; pub(crate) static GLOBAL_STATS: BinderStats = BinderStats::new(); pub(crate) struct BinderStats {    bc: [Atomic<u32>; BC_COUNT],    br: [Atomic<u32>; BR_COUNT],} impl BinderStats {    pub(crate) const fn new() -> Self {        #[expect(clippy::declare_interior_mutable_const)]        const ZERO: Atomic<u32> = Atomic::new(0);         Self {            bc: [ZERO; BC_COUNT],            br: [ZERO; BR_COUNT],        }    }     pub(crate) fn inc_bc(&self, bc: u32) {        let idx = _IOC_NR(bc) as usize;        if let Some(bc_ref) = self.bc.get(idx) {            bc_ref.fetch_add(1, Relaxed);        }    }     pub(crate) fn inc_br(&self, br: u32) {        let idx = _IOC_NR(br) as usize;        if let Some(br_ref) = self.br.get(idx) {            br_ref.fetch_add(1, Relaxed);        }    }     pub(crate) fn debug_print(&self, prefix: &str, m: &SeqFile) {        for (i, cnt) in self.bc.iter().enumerate() {            let cnt = cnt.load(Relaxed);            if cnt > 0 {                seq_print!(m, "{}{}: {}\n", prefix, command_string(i), cnt);            }        }        for (i, cnt) in self.br.iter().enumerate() {            let cnt = cnt.load(Relaxed);            if cnt > 0 {                seq_print!(m, "{}{}: {}\n", prefix, return_string(i), cnt);            }        }    }} mod strings {    use core::str::from_utf8_unchecked;    use kernel::str::{CStr, CStrExt as _};     extern "C" {        static binder_command_strings: [*const u8; super::BC_COUNT];        static binder_return_strings: [*const u8; super::BR_COUNT];    }     pub(super) fn command_string(i: usize) -> &'static str {        // SAFETY: Accessing `binder_command_strings` is always safe.        let c_str_ptr = unsafe { binder_command_strings[i] };        // SAFETY: The `binder_command_strings` array only contains nul-terminated strings.        let bytes = unsafe { CStr::from_char_ptr(c_str_ptr) }.to_bytes();        // SAFETY: The `binder_command_strings` array only contains strings with ascii-chars.        unsafe { from_utf8_unchecked(bytes) }    }     pub(super) fn return_string(i: usize) -> &'static str {        // SAFETY: Accessing `binder_return_strings` is always safe.        let c_str_ptr = unsafe { binder_return_strings[i] };        // SAFETY: The `binder_command_strings` array only contains nul-terminated strings.        let bytes = unsafe { CStr::from_char_ptr(c_str_ptr) }.to_bytes();        // SAFETY: The `binder_command_strings` array only contains strings with ascii-chars.        unsafe { from_utf8_unchecked(bytes) }    }}use strings::{command_string, return_string};