linux-IllusionX/mm/fail_page_alloc.c
Vlastimil Babka 53dabce265 mm, page_alloc: put should_fail_alloc_page() back behing CONFIG_FAIL_PAGE_ALLOC
This mostly reverts commit af3b854492 ("mm/page_alloc.c: allow error
injection").  The commit made should_fail_alloc_page() a noinline function
that's always called from the page allocation hotpath, even if it's empty
because CONFIG_FAIL_PAGE_ALLOC is not enabled, and there is no option to
disable it and prevent the associated function call overhead.

As with the preceding patch "mm, slab: put should_failslab back behind
CONFIG_SHOULD_FAILSLAB" and for the same reasons, put the
should_fail_alloc_page() back behind the config option.  When enabled, the
ALLOW_ERROR_INJECTION and BTF_ID records are preserved so it's not a
complete revert.

Link: https://lkml.kernel.org/r/20240711-b4-fault-injection-reverts-v1-2-9e2651945d68@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andrii Nakryiko <andrii@kernel.org>
Cc: Christoph Lameter <cl@linux.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: David Rientjes <rientjes@google.com>
Cc: Eduard Zingerman <eddyz87@gmail.com>
Cc: Hao Luo <haoluo@google.com>
Cc: Hyeonggon Yoo <42.hyeyoo@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: KP Singh <kpsingh@kernel.org>
Cc: Martin KaFai Lau <martin.lau@linux.dev>
Cc: Mateusz Guzik <mjguzik@gmail.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Song Liu <song@kernel.org>
Cc: Stanislav Fomichev <sdf@fomichev.me>
Cc: Yonghong Song <yonghong.song@linux.dev>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-07-17 21:05:18 -07:00

68 lines
1.7 KiB
C

// SPDX-License-Identifier: GPL-2.0
#include <linux/fault-inject.h>
#include <linux/error-injection.h>
#include <linux/mm.h>
static struct {
struct fault_attr attr;
bool ignore_gfp_highmem;
bool ignore_gfp_reclaim;
u32 min_order;
} fail_page_alloc = {
.attr = FAULT_ATTR_INITIALIZER,
.ignore_gfp_reclaim = true,
.ignore_gfp_highmem = true,
.min_order = 1,
};
static int __init setup_fail_page_alloc(char *str)
{
return setup_fault_attr(&fail_page_alloc.attr, str);
}
__setup("fail_page_alloc=", setup_fail_page_alloc);
bool should_fail_alloc_page(gfp_t gfp_mask, unsigned int order)
{
int flags = 0;
if (order < fail_page_alloc.min_order)
return false;
if (gfp_mask & __GFP_NOFAIL)
return false;
if (fail_page_alloc.ignore_gfp_highmem && (gfp_mask & __GFP_HIGHMEM))
return false;
if (fail_page_alloc.ignore_gfp_reclaim &&
(gfp_mask & __GFP_DIRECT_RECLAIM))
return false;
/* See comment in __should_failslab() */
if (gfp_mask & __GFP_NOWARN)
flags |= FAULT_NOWARN;
return should_fail_ex(&fail_page_alloc.attr, 1 << order, flags);
}
ALLOW_ERROR_INJECTION(should_fail_alloc_page, TRUE);
#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
static int __init fail_page_alloc_debugfs(void)
{
umode_t mode = S_IFREG | 0600;
struct dentry *dir;
dir = fault_create_debugfs_attr("fail_page_alloc", NULL,
&fail_page_alloc.attr);
debugfs_create_bool("ignore-gfp-wait", mode, dir,
&fail_page_alloc.ignore_gfp_reclaim);
debugfs_create_bool("ignore-gfp-highmem", mode, dir,
&fail_page_alloc.ignore_gfp_highmem);
debugfs_create_u32("min-order", mode, dir, &fail_page_alloc.min_order);
return 0;
}
late_initcall(fail_page_alloc_debugfs);
#endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */