e65a5c6edb
This patch adds a few bpf mem allocator functions which will be used in the bpf_local_storage in a later patch. bpf_mem_cache_alloc_flags(..., gfp_t flags) is added. When the flags == GFP_KERNEL, it will fallback to __alloc(..., GFP_KERNEL). bpf_local_storage knows its running context is sleepable (GFP_KERNEL) and provides a better guarantee on memory allocation. bpf_local_storage has some uncommon cases that its selem cannot be reused immediately. It handles its own rcu_head and goes through a rcu_trace gp and then free it. bpf_mem_cache_raw_free() is added for direct free purpose without leaking the LLIST_NODE_SZ internal knowledge. During free time, the 'struct bpf_mem_alloc *ma' is no longer available. However, the caller should know if it is percpu memory or not and it can call different raw_free functions. bpf_local_storage does not support percpu value, so only the non-percpu 'bpf_mem_cache_raw_free()' is added in this patch. Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org> Link: https://lore.kernel.org/r/20230322215246.1675516-2-martin.lau@linux.dev Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.