kernel-hacking-2024-linux-s.../mm/failslab.c
Jani Nikula 6ce2082fd3 fault-inject: improve build for CONFIG_FAULT_INJECTION=n
The fault-inject.h users across the kernel need to add a lot of #ifdef
CONFIG_FAULT_INJECTION to cater for shortcomings in the header.  Make
fault-inject.h self-contained for CONFIG_FAULT_INJECTION=n, and add stubs
for DECLARE_FAULT_ATTR(), setup_fault_attr(), should_fail_ex(), and
should_fail() to allow removal of conditional compilation.

[akpm@linux-foundation.org: repair fallout from no longer including debugfs.h into fault-inject.h]
[akpm@linux-foundation.org: fix drivers/misc/xilinx_tmr_inject.c]
[akpm@linux-foundation.org: Add debugfs.h inclusion to more files, per Stephen]
Link: https://lkml.kernel.org/r/20240813121237.2382534-1-jani.nikula@intel.com
Fixes: 6ff1cb355e ("[PATCH] fault-injection capabilities infrastructure")
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Cc: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Abhinav Kumar <quic_abhinavk@quicinc.com>
Cc: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Cc: Himal Prasad Ghimiray <himal.prasad.ghimiray@intel.com>
Cc: Lucas De Marchi <lucas.demarchi@intel.com>
Cc: Rob Clark <robdclark@gmail.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2024-09-01 20:43:33 -07:00

76 lines
1.7 KiB
C

// SPDX-License-Identifier: GPL-2.0
#include <linux/fault-inject.h>
#include <linux/error-injection.h>
#include <linux/debugfs.h>
#include <linux/slab.h>
#include <linux/mm.h>
#include "slab.h"
static struct {
struct fault_attr attr;
bool ignore_gfp_reclaim;
bool cache_filter;
} failslab = {
.attr = FAULT_ATTR_INITIALIZER,
.ignore_gfp_reclaim = true,
.cache_filter = false,
};
int should_failslab(struct kmem_cache *s, gfp_t gfpflags)
{
int flags = 0;
/* No fault-injection for bootstrap cache */
if (unlikely(s == kmem_cache))
return 0;
if (gfpflags & __GFP_NOFAIL)
return 0;
if (failslab.ignore_gfp_reclaim &&
(gfpflags & __GFP_DIRECT_RECLAIM))
return 0;
if (failslab.cache_filter && !(s->flags & SLAB_FAILSLAB))
return 0;
/*
* In some cases, it expects to specify __GFP_NOWARN
* to avoid printing any information(not just a warning),
* thus avoiding deadlocks. See commit 6b9dbedbe349 for
* details.
*/
if (gfpflags & __GFP_NOWARN)
flags |= FAULT_NOWARN;
return should_fail_ex(&failslab.attr, s->object_size, flags) ? -ENOMEM : 0;
}
ALLOW_ERROR_INJECTION(should_failslab, ERRNO);
static int __init setup_failslab(char *str)
{
return setup_fault_attr(&failslab.attr, str);
}
__setup("failslab=", setup_failslab);
#ifdef CONFIG_FAULT_INJECTION_DEBUG_FS
static int __init failslab_debugfs_init(void)
{
struct dentry *dir;
umode_t mode = S_IFREG | 0600;
dir = fault_create_debugfs_attr("failslab", NULL, &failslab.attr);
if (IS_ERR(dir))
return PTR_ERR(dir);
debugfs_create_bool("ignore-gfp-wait", mode, dir,
&failslab.ignore_gfp_reclaim);
debugfs_create_bool("cache-filter", mode, dir,
&failslab.cache_filter);
return 0;
}
late_initcall(failslab_debugfs_init);
#endif /* CONFIG_FAULT_INJECTION_DEBUG_FS */