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h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=cyrDKc6+UkaIRpwi1rdgsrlg/YNeGkCxs/T+ipMB7oQ=; b=g7EnXko/wyf0WQiL5mY/hafIxjSHVbzwUQZMxD7y2AjmpFOraUFpGjgXeQGUdtmooi7BiD +95iclcvJevGEr+gvO5jx6jh8beqtHZ5ASeZeSEoCl7XDwGCtzYthQqS5MAPUY/QLC7TmR HiZqrlD+ldR0967fvHLseFSrwD1RYtD5DdHcOgBN05ptp5FpiAts9oq7CcneBV1l0PBBsb iiUwVdxtrVsxHeQWpr/qFOUHBKLUiF6bl/a1C/pqihKhWsIc70IgwOS6Yo/R8WFQEzFUuX 2M3VEi7sXTuPLGXGXj6uOfkSd8rezz/WHUAHHwapS5yPKFb79KXzQOuMYOfgDg== From: Eugene Mavick Date: Sat, 11 Jul 2026 12:40:20 +0800 Subject: [PATCH v3 2/5] refcount: add ref_trace_final_put tracepoint MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260711-refcount-final-put-trace-v3-2-674c8f03d9f9@mavick.dev> References: <20260711-refcount-final-put-trace-v3-0-674c8f03d9f9@mavick.dev> In-Reply-To: <20260711-refcount-final-put-trace-v3-0-674c8f03d9f9@mavick.dev> To: Will Deacon , Peter Zijlstra , Boqun Feng , Mark Rutland , Gary Guo , Steven Rostedt , Masami Hiramatsu , Mathieu Desnoyers , Andrew Morton , Dennis Zhou , Tejun Heo , Christoph Lameter Cc: linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-mm@kvack.org, Eugene Mavick X-Developer-Signature: v=1; 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Signed-off-by: Eugene Mavick --- include/linux/refcount.h | 2 ++ lib/refcount.c | 8 +++++++- 2 files changed, 9 insertions(+), 1 deletion(-) diff --git a/include/linux/refcount.h b/include/linux/refcount.h index ba7657ced281..70d07a462da1 100644 --- a/include/linux/refcount.h +++ b/include/linux/refcount.h @@ -107,6 +107,7 @@ #include #include #include +#include struct mutex; @@ -393,6 +394,7 @@ bool __refcount_sub_and_test(int i, refcount_t *r, int *oldp) if (old > 0 && old == i) { smp_acquire__after_ctrl_dep(); + do_trace_ref_final_put(r); return true; } diff --git a/lib/refcount.c b/lib/refcount.c index a207a8f22b3c..cd7e32df3919 100644 --- a/lib/refcount.c +++ b/lib/refcount.c @@ -7,6 +7,7 @@ #include #include #include +#include #define REFCOUNT_WARN(str) WARN_ONCE(1, "refcount_t: " str ".\n") @@ -56,7 +57,12 @@ bool refcount_dec_if_one(refcount_t *r) { int val = 1; - return atomic_try_cmpxchg_release(&r->refs, &val, 0); + bool ret = atomic_try_cmpxchg_release(&r->refs, &val, 0); + + if (ret) + do_trace_ref_final_put(r); + + return ret; } EXPORT_SYMBOL(refcount_dec_if_one); -- 2.51.2