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// SPDX-License-Identifier: GPL-2.0
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// Copyright (C) 2025 Google LLC.
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//! Keep track of statistics for binder_logs.
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use crate::defs::*;
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use core::sync::atomic::{AtomicU32, Ordering::Relaxed};
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use kernel::{ioctl::_IOC_NR, seq_file::SeqFile, seq_print};
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const BC_COUNT: usize = _IOC_NR(BC_REPLY_SG) as usize + 1;
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const BR_COUNT: usize = _IOC_NR(BR_TRANSACTION_PENDING_FROZEN) as usize + 1;
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pub(crate) static GLOBAL_STATS: BinderStats = BinderStats::new();
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pub(crate) struct BinderStats {
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    bc: [AtomicU32; BC_COUNT],
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    br: [AtomicU32; BR_COUNT],
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}
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impl BinderStats {
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    pub(crate) const fn new() -> Self {
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        #[expect(clippy::declare_interior_mutable_const)]
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        const ZERO: AtomicU32 = AtomicU32::new(0);
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        Self {
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            bc: [ZERO; BC_COUNT],
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            br: [ZERO; BR_COUNT],
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        }
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    }
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    pub(crate) fn inc_bc(&self, bc: u32) {
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        let idx = _IOC_NR(bc) as usize;
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        if let Some(bc_ref) = self.bc.get(idx) {
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            bc_ref.fetch_add(1, Relaxed);
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        }
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    }
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    pub(crate) fn inc_br(&self, br: u32) {
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        let idx = _IOC_NR(br) as usize;
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        if let Some(br_ref) = self.br.get(idx) {
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            br_ref.fetch_add(1, Relaxed);
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        }
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    }
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    pub(crate) fn debug_print(&self, prefix: &str, m: &SeqFile) {
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        for (i, cnt) in self.bc.iter().enumerate() {
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            let cnt = cnt.load(Relaxed);
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            if cnt > 0 {
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                seq_print!(m, "{}{}: {}\n", prefix, command_string(i), cnt);
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            }
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        }
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        for (i, cnt) in self.br.iter().enumerate() {
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            let cnt = cnt.load(Relaxed);
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            if cnt > 0 {
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                seq_print!(m, "{}{}: {}\n", prefix, return_string(i), cnt);
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            }
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        }
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    }
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}
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mod strings {
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    use core::str::from_utf8_unchecked;
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    use kernel::str::CStr;
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    extern "C" {
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        static binder_command_strings: [*const u8; super::BC_COUNT];
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        static binder_return_strings: [*const u8; super::BR_COUNT];
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    }
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    pub(super) fn command_string(i: usize) -> &'static str {
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        // SAFETY: Accessing `binder_command_strings` is always safe.
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        let c_str_ptr = unsafe { binder_command_strings[i] };
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        // SAFETY: The `binder_command_strings` array only contains nul-terminated strings.
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        let bytes = unsafe { CStr::from_char_ptr(c_str_ptr) }.as_bytes();
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        // SAFETY: The `binder_command_strings` array only contains strings with ascii-chars.
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        unsafe { from_utf8_unchecked(bytes) }
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    }
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    pub(super) fn return_string(i: usize) -> &'static str {
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        // SAFETY: Accessing `binder_return_strings` is always safe.
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        let c_str_ptr = unsafe { binder_return_strings[i] };
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        // SAFETY: The `binder_command_strings` array only contains nul-terminated strings.
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        let bytes = unsafe { CStr::from_char_ptr(c_str_ptr) }.as_bytes();
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        // SAFETY: The `binder_command_strings` array only contains strings with ascii-chars.
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        unsafe { from_utf8_unchecked(bytes) }
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    }
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}
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use strings::{command_string, return_string};
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