From 4617721c502b2ddaa4e324e86da4997edf738fa5 Mon Sep 17 00:00:00 2001 From: Steven Rostedt Date: Wed, 2 Sep 2026 09:55:01 -0400 Subject: ftrace: Synchronize the initialization of ftrace_ops There's some internal state that ftrace_ops needs to have set, but since it can be declared outside of the ftrace.c code, it calls ftrace_ops_init() on the ops in every global function. The issue is that if two tasks call it on the same ops at the same time it is possible to have the initialization of one corrupt the initialization of the other call. Create a ops_mutex to use to synchronize every initialization of the ftrace_ops. The mutex is taken within checking the ftrace_ops flag that states it was initializied but the flag is checked again after the mutex has been taken. Checking first outside the mutex allows it to shortcut having to take the mutex. But then the check needs to be done again after the mute is taken in case of races. Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260902095501.6b59af20@gandalf.local.home Fixes: f04f24fb7e48d ("ftrace, kprobes: Fix a deadlock on ftrace_regex_lock") Reported-by: sashiko-bot@kernel.org Close: https://lore.kernel.org/all/20260829025528.49A831F000E9@smtp.kernel.org/ Signed-off-by: Steven Rostedt --- lib/raid/raid6/arm/neon.c | 51 ++++++++++++ lib/raid/raid6/arm/neon.h | 22 +++++ lib/raid/raid6/arm/neon.uc | 153 ++++++++++++++++++++++++++++++++++ lib/raid/raid6/arm/pq_arch.h | 21 +++++ lib/raid/raid6/arm/recov_neon.c | 86 +++++++++++++++++++ lib/raid/raid6/arm/recov_neon_inner.c | 111 ++++++++++++++++++++++++ 6 files changed, 444 insertions(+) create mode 100644 lib/raid/raid6/arm/neon.c create mode 100644 lib/raid/raid6/arm/neon.h create mode 100644 lib/raid/raid6/arm/neon.uc create mode 100644 lib/raid/raid6/arm/pq_arch.h create mode 100644 lib/raid/raid6/arm/recov_neon.c create mode 100644 lib/raid/raid6/arm/recov_neon_inner.c (limited to 'lib/raid/raid6/arm') diff --git a/lib/raid/raid6/arm/neon.c b/lib/raid/raid6/arm/neon.c new file mode 100644 index 000000000..af90869aa --- /dev/null +++ b/lib/raid/raid6/arm/neon.c @@ -0,0 +1,51 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * RAID6 syndrome calculation using ARM NEON intrinsics + * + * Copyright (C) 2013 Linaro Ltd + */ + +#include +#include "algos.h" + +/* + * There are 2 reasons these wrappers are kept in a separate compilation unit + * from the actual implementations in neonN.c (generated from neon.uc by + * unroll.awk): + * - the actual implementations use NEON intrinsics, and the GCC support header + * (arm_neon.h) is not fully compatible (type wise) with the kernel; + * - the neonN.c files are compiled with -mfpu=neon and optimization enabled, + * and we have to make sure that we never use *any* NEON/VFP instructions + * outside a kernel_neon_begin()/kernel_neon_end() pair. + */ + +#define RAID6_NEON_WRAPPER(_n) \ + static void raid6_neon ## _n ## _gen_syndrome(int disks, \ + size_t bytes, void **ptrs) \ + { \ + void raid6_neon ## _n ## _gen_syndrome_real(int, \ + unsigned long, void**); \ + scoped_ksimd() \ + raid6_neon ## _n ## _gen_syndrome_real(disks, \ + (unsigned long)bytes, ptrs); \ + } \ + static void raid6_neon ## _n ## _xor_syndrome(int disks, \ + int start, int stop, \ + size_t bytes, void **ptrs) \ + { \ + void raid6_neon ## _n ## _xor_syndrome_real(int, \ + int, int, unsigned long, void**); \ + scoped_ksimd() \ + raid6_neon ## _n ## _xor_syndrome_real(disks, \ + start, stop, (unsigned long)bytes, ptrs);\ + } \ + struct raid6_calls const raid6_neonx ## _n = { \ + .gen_syndrome = raid6_neon ## _n ## _gen_syndrome, \ + .xor_syndrome = raid6_neon ## _n ## _xor_syndrome, \ + .name = "neonx" #_n, \ + } + +RAID6_NEON_WRAPPER(1); +RAID6_NEON_WRAPPER(2); +RAID6_NEON_WRAPPER(4); +RAID6_NEON_WRAPPER(8); diff --git a/lib/raid/raid6/arm/neon.h b/lib/raid/raid6/arm/neon.h new file mode 100644 index 000000000..2ca41ee9b --- /dev/null +++ b/lib/raid/raid6/arm/neon.h @@ -0,0 +1,22 @@ +// SPDX-License-Identifier: GPL-2.0-only + +void raid6_neon1_gen_syndrome_real(int disks, unsigned long bytes, void **ptrs); +void raid6_neon1_xor_syndrome_real(int disks, int start, int stop, + unsigned long bytes, void **ptrs); +void raid6_neon2_gen_syndrome_real(int disks, unsigned long bytes, void **ptrs); +void raid6_neon2_xor_syndrome_real(int disks, int start, int stop, + unsigned long bytes, void **ptrs); +void raid6_neon4_gen_syndrome_real(int disks, unsigned long bytes, void **ptrs); +void raid6_neon4_xor_syndrome_real(int disks, int start, int stop, + unsigned long bytes, void **ptrs); +void raid6_neon8_gen_syndrome_real(int disks, unsigned long bytes, void **ptrs); +void raid6_neon8_xor_syndrome_real(int disks, int start, int stop, + unsigned long bytes, void **ptrs); +void __raid6_2data_recov_neon(int bytes, uint8_t *p, uint8_t *q, uint8_t *dp, + uint8_t *dq, const uint8_t *pbmul, + const uint8_t *qmul); + +void __raid6_datap_recov_neon(int bytes, uint8_t *p, uint8_t *q, uint8_t *dq, + const uint8_t *qmul); + + diff --git a/lib/raid/raid6/arm/neon.uc b/lib/raid/raid6/arm/neon.uc new file mode 100644 index 000000000..14a9fc2c6 --- /dev/null +++ b/lib/raid/raid6/arm/neon.uc @@ -0,0 +1,153 @@ +/* ----------------------------------------------------------------------- + * + * neon.uc - RAID-6 syndrome calculation using ARM NEON instructions + * + * Copyright (C) 2012 Rob Herring + * Copyright (C) 2015 Linaro Ltd. + * + * Based on altivec.uc: + * Copyright 2002-2004 H. Peter Anvin - All Rights Reserved + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, Inc., 53 Temple Place Ste 330, + * Boston MA 02111-1307, USA; either version 2 of the License, or + * (at your option) any later version; incorporated herein by reference. + * + * ----------------------------------------------------------------------- */ + +/* + * neon$#.c + * + * $#-way unrolled NEON intrinsics math RAID-6 instruction set + * + * This file is postprocessed using unroll.awk + */ + +#include +#include "arm/neon.h" + +typedef uint8x16_t unative_t; + +#define NSIZE sizeof(unative_t) + +/* + * The SHLBYTE() operation shifts each byte left by 1, *not* + * rolling over into the next byte + */ +static inline unative_t SHLBYTE(unative_t v) +{ + return vshlq_n_u8(v, 1); +} + +/* + * The MASK() operation returns 0xFF in any byte for which the high + * bit is 1, 0x00 for any byte for which the high bit is 0. + */ +static inline unative_t MASK(unative_t v) +{ + return (unative_t)vshrq_n_s8((int8x16_t)v, 7); +} + +static inline unative_t PMUL(unative_t v, unative_t u) +{ + return (unative_t)vmulq_p8((poly8x16_t)v, (poly8x16_t)u); +} + +void raid6_neon$#_gen_syndrome_real(int disks, unsigned long bytes, void **ptrs) +{ + uint8_t **dptr = (uint8_t **)ptrs; + uint8_t *p, *q; + int d, z, z0; + + register unative_t wd$$, wq$$, wp$$, w1$$, w2$$; + const unative_t x1d = vdupq_n_u8(0x1d); + + z0 = disks - 3; /* Highest data disk */ + p = dptr[z0+1]; /* XOR parity */ + q = dptr[z0+2]; /* RS syndrome */ + + for ( d = 0 ; d < bytes ; d += NSIZE*$# ) { + wq$$ = wp$$ = vld1q_u8(&dptr[z0][d+$$*NSIZE]); + for ( z = z0-1 ; z >= 0 ; z-- ) { + wd$$ = vld1q_u8(&dptr[z][d+$$*NSIZE]); + wp$$ = veorq_u8(wp$$, wd$$); + w2$$ = MASK(wq$$); + w1$$ = SHLBYTE(wq$$); + + w2$$ = vandq_u8(w2$$, x1d); + w1$$ = veorq_u8(w1$$, w2$$); + wq$$ = veorq_u8(w1$$, wd$$); + } + vst1q_u8(&p[d+NSIZE*$$], wp$$); + vst1q_u8(&q[d+NSIZE*$$], wq$$); + } +} + +void raid6_neon$#_xor_syndrome_real(int disks, int start, int stop, + unsigned long bytes, void **ptrs) +{ + uint8_t **dptr = (uint8_t **)ptrs; + uint8_t *p, *q; + int d, z, z0; + + register unative_t wd$$, wq$$, wp$$, w1$$, w2$$; + const unative_t x1d = vdupq_n_u8(0x1d); + + z0 = stop; /* P/Q right side optimization */ + p = dptr[disks-2]; /* XOR parity */ + q = dptr[disks-1]; /* RS syndrome */ + + for ( d = 0 ; d < bytes ; d += NSIZE*$# ) { + wq$$ = vld1q_u8(&dptr[z0][d+$$*NSIZE]); + wp$$ = veorq_u8(vld1q_u8(&p[d+$$*NSIZE]), wq$$); + + /* P/Q data pages */ + for ( z = z0-1 ; z >= start ; z-- ) { + wd$$ = vld1q_u8(&dptr[z][d+$$*NSIZE]); + wp$$ = veorq_u8(wp$$, wd$$); + w2$$ = MASK(wq$$); + w1$$ = SHLBYTE(wq$$); + + w2$$ = vandq_u8(w2$$, x1d); + w1$$ = veorq_u8(w1$$, w2$$); + wq$$ = veorq_u8(w1$$, wd$$); + } + /* P/Q left side optimization */ + for ( z = start-1 ; z >= 3 ; z -= 4 ) { + w2$$ = vshrq_n_u8(wq$$, 4); + w1$$ = vshlq_n_u8(wq$$, 4); + + w2$$ = PMUL(w2$$, x1d); + wq$$ = veorq_u8(w1$$, w2$$); + } + + switch (z) { + case 2: + w2$$ = vshrq_n_u8(wq$$, 5); + w1$$ = vshlq_n_u8(wq$$, 3); + + w2$$ = PMUL(w2$$, x1d); + wq$$ = veorq_u8(w1$$, w2$$); + break; + case 1: + w2$$ = vshrq_n_u8(wq$$, 6); + w1$$ = vshlq_n_u8(wq$$, 2); + + w2$$ = PMUL(w2$$, x1d); + wq$$ = veorq_u8(w1$$, w2$$); + break; + case 0: + w2$$ = MASK(wq$$); + w1$$ = SHLBYTE(wq$$); + + w2$$ = vandq_u8(w2$$, x1d); + wq$$ = veorq_u8(w1$$, w2$$); + } + w1$$ = vld1q_u8(&q[d+NSIZE*$$]); + wq$$ = veorq_u8(wq$$, w1$$); + + vst1q_u8(&p[d+NSIZE*$$], wp$$); + vst1q_u8(&q[d+NSIZE*$$], wq$$); + } +} diff --git a/lib/raid/raid6/arm/pq_arch.h b/lib/raid/raid6/arm/pq_arch.h new file mode 100644 index 000000000..3f876ea67 --- /dev/null +++ b/lib/raid/raid6/arm/pq_arch.h @@ -0,0 +1,21 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ + +#include + +extern const struct raid6_calls raid6_neonx1; +extern const struct raid6_calls raid6_neonx2; +extern const struct raid6_calls raid6_neonx4; +extern const struct raid6_calls raid6_neonx8; +extern const struct raid6_recov_calls raid6_recov_neon; + +static __always_inline void __init arch_raid6_init(void) +{ + raid6_algo_add_default(); + if (cpu_has_neon()) { + raid6_algo_add(&raid6_neonx1); + raid6_algo_add(&raid6_neonx2); + raid6_algo_add(&raid6_neonx4); + raid6_algo_add(&raid6_neonx8); + raid6_recov_algo_add(&raid6_recov_neon); + } +} diff --git a/lib/raid/raid6/arm/recov_neon.c b/lib/raid/raid6/arm/recov_neon.c new file mode 100644 index 000000000..1524050d0 --- /dev/null +++ b/lib/raid/raid6/arm/recov_neon.c @@ -0,0 +1,86 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2012 Intel Corporation + * Copyright (C) 2017 Linaro Ltd. + */ + +#include +#include +#include +#include "algos.h" +#include "arm/neon.h" + +static void raid6_2data_recov_neon(int disks, size_t bytes, int faila, + int failb, void **ptrs) +{ + u8 *p, *q, *dp, *dq; + const u8 *pbmul; /* P multiplier table for B data */ + const u8 *qmul; /* Q multiplier table (for both) */ + + p = (u8 *)ptrs[disks - 2]; + q = (u8 *)ptrs[disks - 1]; + + /* + * Compute syndrome with zero for the missing data pages + * Use the dead data pages as temporary storage for + * delta p and delta q + */ + dp = (u8 *)ptrs[faila]; + ptrs[faila] = page_address(ZERO_PAGE(0)); + ptrs[disks - 2] = dp; + dq = (u8 *)ptrs[failb]; + ptrs[failb] = page_address(ZERO_PAGE(0)); + ptrs[disks - 1] = dq; + + raid6_gen_syndrome(disks, bytes, ptrs); + + /* Restore pointer table */ + ptrs[faila] = dp; + ptrs[failb] = dq; + ptrs[disks - 2] = p; + ptrs[disks - 1] = q; + + /* Now, pick the proper data tables */ + pbmul = raid6_vgfmul[raid6_gfexi[failb-faila]]; + qmul = raid6_vgfmul[raid6_gfinv[raid6_gfexp[faila] ^ + raid6_gfexp[failb]]]; + + scoped_ksimd() + __raid6_2data_recov_neon(bytes, p, q, dp, dq, pbmul, qmul); +} + +static void raid6_datap_recov_neon(int disks, size_t bytes, int faila, + void **ptrs) +{ + u8 *p, *q, *dq; + const u8 *qmul; /* Q multiplier table */ + + p = (u8 *)ptrs[disks - 2]; + q = (u8 *)ptrs[disks - 1]; + + /* + * Compute syndrome with zero for the missing data page + * Use the dead data page as temporary storage for delta q + */ + dq = (u8 *)ptrs[faila]; + ptrs[faila] = page_address(ZERO_PAGE(0)); + ptrs[disks - 1] = dq; + + raid6_gen_syndrome(disks, bytes, ptrs); + + /* Restore pointer table */ + ptrs[faila] = dq; + ptrs[disks - 1] = q; + + /* Now, pick the proper data tables */ + qmul = raid6_vgfmul[raid6_gfinv[raid6_gfexp[faila]]]; + + scoped_ksimd() + __raid6_datap_recov_neon(bytes, p, q, dq, qmul); +} + +const struct raid6_recov_calls raid6_recov_neon = { + .data2 = raid6_2data_recov_neon, + .datap = raid6_datap_recov_neon, + .name = "neon", +}; diff --git a/lib/raid/raid6/arm/recov_neon_inner.c b/lib/raid/raid6/arm/recov_neon_inner.c new file mode 100644 index 000000000..53c355efa --- /dev/null +++ b/lib/raid/raid6/arm/recov_neon_inner.c @@ -0,0 +1,111 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2012 Intel Corporation + * Copyright (C) 2017 Linaro Ltd. + */ + +#include +#include "arm/neon.h" + +#ifdef CONFIG_ARM +/* + * AArch32 does not provide this intrinsic natively because it does not + * implement the underlying instruction. AArch32 only provides a 64-bit + * wide vtbl.8 instruction, so use that instead. + */ +static uint8x16_t vqtbl1q_u8(uint8x16_t a, uint8x16_t b) +{ + union { + uint8x16_t val; + uint8x8x2_t pair; + } __a = { a }; + + return vcombine_u8(vtbl2_u8(__a.pair, vget_low_u8(b)), + vtbl2_u8(__a.pair, vget_high_u8(b))); +} +#endif + +void __raid6_2data_recov_neon(int bytes, uint8_t *p, uint8_t *q, uint8_t *dp, + uint8_t *dq, const uint8_t *pbmul, + const uint8_t *qmul) +{ + uint8x16_t pm0 = vld1q_u8(pbmul); + uint8x16_t pm1 = vld1q_u8(pbmul + 16); + uint8x16_t qm0 = vld1q_u8(qmul); + uint8x16_t qm1 = vld1q_u8(qmul + 16); + uint8x16_t x0f = vdupq_n_u8(0x0f); + + /* + * while ( bytes-- ) { + * uint8_t px, qx, db; + * + * px = *p ^ *dp; + * qx = qmul[*q ^ *dq]; + * *dq++ = db = pbmul[px] ^ qx; + * *dp++ = db ^ px; + * p++; q++; + * } + */ + + while (bytes) { + uint8x16_t vx, vy, px, qx, db; + + px = veorq_u8(vld1q_u8(p), vld1q_u8(dp)); + vx = veorq_u8(vld1q_u8(q), vld1q_u8(dq)); + + vy = vshrq_n_u8(vx, 4); + vx = vqtbl1q_u8(qm0, vandq_u8(vx, x0f)); + vy = vqtbl1q_u8(qm1, vy); + qx = veorq_u8(vx, vy); + + vy = vshrq_n_u8(px, 4); + vx = vqtbl1q_u8(pm0, vandq_u8(px, x0f)); + vy = vqtbl1q_u8(pm1, vy); + vx = veorq_u8(vx, vy); + db = veorq_u8(vx, qx); + + vst1q_u8(dq, db); + vst1q_u8(dp, veorq_u8(db, px)); + + bytes -= 16; + p += 16; + q += 16; + dp += 16; + dq += 16; + } +} + +void __raid6_datap_recov_neon(int bytes, uint8_t *p, uint8_t *q, uint8_t *dq, + const uint8_t *qmul) +{ + uint8x16_t qm0 = vld1q_u8(qmul); + uint8x16_t qm1 = vld1q_u8(qmul + 16); + uint8x16_t x0f = vdupq_n_u8(0x0f); + + /* + * while (bytes--) { + * *p++ ^= *dq = qmul[*q ^ *dq]; + * q++; dq++; + * } + */ + + while (bytes) { + uint8x16_t vx, vy; + + vx = veorq_u8(vld1q_u8(q), vld1q_u8(dq)); + + vy = vshrq_n_u8(vx, 4); + vx = vqtbl1q_u8(qm0, vandq_u8(vx, x0f)); + vy = vqtbl1q_u8(qm1, vy); + vx = veorq_u8(vx, vy); + vy = veorq_u8(vx, vld1q_u8(p)); + + vst1q_u8(dq, vx); + vst1q_u8(p, vy); + + bytes -= 16; + p += 16; + q += 16; + dq += 16; + } +} -- cgit v1.3.1