On Wed, Feb 14, 2024 at 8:40 AM Nikhil V <quic_nprakash@xxxxxxxxxxx> wrote: > > Currently the default compression algorithm is selected based on > compile time options. Introduce a module parameter "hibernate.compressor" > to override this behaviour. > > Different compression algorithms have different characteristics and > hibernation may benefit when it uses any of these algorithms, especially > when a secondary algorithm(LZ4) offers better decompression speeds over a > default algorithm(LZO), which in turn reduces hibernation image restore > time. > > Users can override the default algorithm in two ways: > 1) Passing "hibernate.compressor" as kernel command line parameter. > Usage: > LZO: hibernate.compressor=lzo > LZ4: hibernate.compressor=lz4 > > 2) Specifying the algorithm at runtime. > Usage: > LZO: echo lzo > /sys/module/hibernate/parameters/compressor > LZ4: echo lz4 > /sys/module/hibernate/parameters/compressor > > Currently LZO and LZ4 are the supported algorithms. LZO is the default > compression algorithm used with hibernation. > > Signed-off-by: Nikhil V <quic_nprakash@xxxxxxxxxxx> > --- > This patch is dependent on the patch series, [1] (patches 1/4 to 3/4). > This is picked in linux-next, [2]. > [1] https://lore.kernel.org/all/cover.1705927916.git.quic_nprakash@xxxxxxxxxxx/ > [2] https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/log/kernel/power?h=next-20240212 > > Changes in v2: > Changes to incorporate suggestions from Randy Dunlap: > - Update documentation to specify the default compression algorithm. > Link to v1: > https://lore.kernel.org/all/3776355f920c1af44490e076072f93bafdf128cc.1707740870.git.quic_nprakash@xxxxxxxxxxx/ > > .../admin-guide/kernel-parameters.txt | 11 ++++ > kernel/power/hibernate.c | 57 ++++++++++++++++++- > 2 files changed, 65 insertions(+), 3 deletions(-) > > diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt > index 31b3a25680d0..8f7fb911b2cc 100644 > --- a/Documentation/admin-guide/kernel-parameters.txt > +++ b/Documentation/admin-guide/kernel-parameters.txt > @@ -1748,6 +1748,17 @@ > (that will set all pages holding image data > during restoration read-only). > > + hibernate.compressor= [HIBERNATION] Compression algorithm to be > + used with hibernation. > + Format: { lzo | lz4 } > + Default: lzo > + > + lzo: Select LZO compression algorithm to > + compress/decompress hibernation image. > + > + lz4: Select LZ4 compression algorithm to > + compress/decompress hibernation image. > + > highmem=nn[KMG] [KNL,BOOT] forces the highmem zone to have an exact > size of <nn>. This works even on boxes that have no > highmem otherwise. This also works to reduce highmem > diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c > index 219191d6d0e8..43b1a82e800c 100644 > --- a/kernel/power/hibernate.c > +++ b/kernel/power/hibernate.c > @@ -47,7 +47,7 @@ dev_t swsusp_resume_device; > sector_t swsusp_resume_block; > __visible int in_suspend __nosavedata; > > -static const char *default_compressor = CONFIG_HIBERNATION_DEF_COMP; > +static char hibernate_compressor[CRYPTO_MAX_ALG_NAME] = CONFIG_HIBERNATION_DEF_COMP; > > /* > * Compression/decompression algorithm to be used while saving/loading > @@ -748,7 +748,7 @@ int hibernate(void) > * Query for the compression algorithm support if compression is enabled. > */ > if (!nocompress) { > - strscpy(hib_comp_algo, default_compressor, sizeof(hib_comp_algo)); > + strscpy(hib_comp_algo, hibernate_compressor, sizeof(hib_comp_algo)); > if (crypto_has_comp(hib_comp_algo, 0, 0) != 1) { > pr_err("%s compression is not available\n", hib_comp_algo); > return -EOPNOTSUPP; > @@ -999,7 +999,7 @@ static int software_resume(void) > if (swsusp_header_flags & SF_COMPRESSION_ALG_LZ4) > strscpy(hib_comp_algo, COMPRESSION_ALGO_LZ4, sizeof(hib_comp_algo)); > else > - strscpy(hib_comp_algo, default_compressor, sizeof(hib_comp_algo)); > + strscpy(hib_comp_algo, COMPRESSION_ALGO_LZO, sizeof(hib_comp_algo)); > if (crypto_has_comp(hib_comp_algo, 0, 0) != 1) { > pr_err("%s compression is not available\n", hib_comp_algo); > error = -EOPNOTSUPP; > @@ -1422,6 +1422,57 @@ static int __init nohibernate_setup(char *str) > return 1; > } > > +static const char * const comp_alg_enabled[] = { > +#if IS_ENABLED(CONFIG_CRYPTO_LZO) > + COMPRESSION_ALGO_LZO, > +#endif > +#if IS_ENABLED(CONFIG_CRYPTO_LZ4) > + COMPRESSION_ALGO_LZ4, > +#endif > +}; > + > +static int hibernate_compressor_param_set(const char *compressor, > + const struct kernel_param *kp) > +{ > + unsigned int sleep_flags; > + int index, ret; > + > + sleep_flags = lock_system_sleep(); > + > + index = sysfs_match_string(comp_alg_enabled, compressor); > + if (index >= 0) { > + ret = param_set_copystring(comp_alg_enabled[index], kp); > + if (!ret) > + strscpy(hib_comp_algo, comp_alg_enabled[index], > + sizeof(hib_comp_algo)); > + } else { > + ret = index; > + } > + > + unlock_system_sleep(sleep_flags); > + > + if (ret) > + pr_debug("Cannot set specified compressor %s\n", > + compressor); > + > + return ret; > +} > + > +static const struct kernel_param_ops hibernate_compressor_param_ops = { > + .set = hibernate_compressor_param_set, > + .get = param_get_string, > +}; > + > +static struct kparam_string hibernate_compressor_param_string = { > + .maxlen = sizeof(hibernate_compressor), > + .string = hibernate_compressor, > +}; > + > +module_param_cb(compressor, &hibernate_compressor_param_ops, > + &hibernate_compressor_param_string, 0644); > +MODULE_PARM_DESC(compressor, > + "Compression algorithm to be used with hibernation"); > + > __setup("noresume", noresume_setup); > __setup("resume_offset=", resume_offset_setup); > __setup("resume=", resume_setup); > -- Applied as 6.9 material, thanks!
