mm: Use __do_krealloc to do the krealloc job (e21827aa) · Commits · 戴 / test

Without this patch we can get (many) kmem trace events with call site at krealloc(). This happens because krealloc is calling __krealloc, which performs the allocation through kmalloc_track_caller. Since neither krealloc nor __krealloc are marked inline explicitly, the caller can be traced as being krealloc, which clearly is not the intended behavior. This patch allows to get the real caller of krealloc, by creating an always inlined function __do_krealloc, thus tracing the call site accurately. Acked-by:

Christoph Lameter <cl@linux.com> Cc: Glauber Costa <glommer@parallels.com> Signed-off-by:

Ezequiel Garcia <elezegarcia@gmail.com> Signed-off-by:

Pekka Enberg <penberg@kernel.org>

mm/util.c

+21 −14

Original line number	Diff line number	Diff line
		@@ -105,6 +105,25 @@ void memdup_user(const void __user src, size_t len)
		}
		EXPORT_SYMBOL(memdup_user);

		static __always_inline void __do_krealloc(const void p, size_t new_size,
		gfp_t flags)
		{
		void *ret;
		size_t ks = 0;

		if (p)
		ks = ksize(p);

		if (ks >= new_size)
		return (void *)p;

		ret = kmalloc_track_caller(new_size, flags);
		if (ret && p)
		memcpy(ret, p, ks);

		return ret;
		}

		/**
		* __krealloc - like krealloc() but don't free @p.
		* @p: object to reallocate memory for.
		@@ -117,23 +136,11 @@ EXPORT_SYMBOL(memdup_user);
		*/
		void __krealloc(const void p, size_t new_size, gfp_t flags)
		{
		void *ret;
		size_t ks = 0;

		if (unlikely(!new_size))
		return ZERO_SIZE_PTR;

		if (p)
		ks = ksize(p);
		return __do_krealloc(p, new_size, flags);

		if (ks >= new_size)
		return (void *)p;

		ret = kmalloc_track_caller(new_size, flags);
		if (ret && p)
		memcpy(ret, p, ks);

		return ret;
		}
		EXPORT_SYMBOL(__krealloc);

		@@ -157,7 +164,7 @@ void krealloc(const void p, size_t new_size, gfp_t flags)
		return ZERO_SIZE_PTR;
		}

		ret = __krealloc(p, new_size, flags);
		ret = __do_krealloc(p, new_size, flags);
		if (ret && p != ret)
		kfree(p);

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